power plant sec

8/6/2019 Power Plant Sec

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Signature of Bidder Signature of Purchaser1

FOR AUTHORISED USE ONLY

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GOVERNMENT OF MAHARASHTRAWATER RESOURCES DEPARTMENT

KAL HYDRO ELECTRIC PROJECT

(1 X 15 MW)

BIDDING DOCUMENT NO. SEGEMC/KAL/E&M/1

FOR

SUPPLY, ERECTION, TESTING AND COMMISSIONING OF TURBINE,GENERATOR AND ASSOCIATED EQUIPMENT .

VOLUME-I COMMERCIAL TERMS AND CONDITIONS OF CONTRACTVOLUME-II TECHNICAL SPECIFICATIONS OF TURBINE,

GENERATOR & ASSOCIATED EQUIPMENTS

VOLUME-II

OFFICE OF THE

CHIEF ENGINEER (ELECTRICAL)

HYDRO PROJECTS,

HSBC BANK BUILDING,

4TH

FLOOR, M.G.ROAD,

FORT, MUMBAI-400 001.

TEL. (022) 22670074, 22674867

FAX. (022) 22674996




INDEX

Sr.No. Description Page No

SECTION – I INTENT OF SPECIFICATION 3-14

SECTION - II GENERAL REQUIREMENT 15-60

SECT ION II I SCHEDULE OF REQUIREMENT 61-76

SECTION IV MATERIAL OF MAJOR COMPONENT 77-82

SE CT IO N V TECHNICAL SPECIFICATION OF

TURBINE

83-162

SECTION VI TECHNICAL SPECIFICATION OF MAIN

INLET VALVES

163-183

SECTION VII TECHNICAL SPECIFICATIONS OF

STATION AUXILIARIES

184-208

SECTION VIII TECHNICAL SPECIFICATIONS OF

GENERATOR

209-291

SECTION IX TECHNICAL SPECIFICATIONS OF

SUPERVISORY CONTROL AND DATA

ACQUISITION SYSTEM

292-311

SECTIO N X TECHNICAL SPECIFICATION OF FORLAVT CUBICLE, NG CUBICLE, BUSDUCT,

AND ISOLATOR.

312-324

SECTION XI PROTECTIVE GEAR 325-3 31

SECTION XII DRAWINGS 332




SECTION – I

INTENT OF SPECIFICATIONS




SECTION – I

INTENT OF SPECIFICATION

INDEX

Sr.No. Description Page No

1.1

1.2

1.3

1.4

1.5

1.6

1.71.8

1.9

Scope of work

Hydraulic Data

Rating Requirements

Design Requirements

Layout Constraints

Design study/ calculation

Model test of TurbineData Sheets

Drawings and Data to be submitted with

Bid.

ANNEXURES-1-1

List of Drawings and Data to be submitted

with Bid.

5

6

7

7

9

10

1212

12

13




SECTION- I

INTENT OF SPECIFICATION

1.1. SCOPE OF WORK:-

The scope of work comprise of the following:

To undertake the complete engineering, design, manufacture, assembly,

testing at manufacturer’s works before dispatch, proper packing, loading

at works, transport, delivery to site, unloading at site and stacking,

handling, loading at site store, transport at site of erection, onsite

erection, testing and commissioning and trial run of following plant and

equipment with spares, tools and tackles including composite insurance

upto taking over. The brief details of the plant equipment are as below:

Mechanical Lot :-

One number of Vertical shaft single stage turbine of Francis type.

Turbine shall be capable of developing Rated output of at least 15625

kW at 106m rated net head complete with governing equipment and all

auxiliaries.

One Number: Butterfly valve (2000 mm diameter approx) suitable for

connection with spiral inlet of turbine. Valve shall be designed for apressure of 175m of water column.

Penstock pipes. Matching pipes between penstock and Butterfly valve,

between Butterfly valve and spiral case of the turbine, between draft

tube liner and tail race joint. Further lot shall comprise of stiffeners,

supports and anchors for proper embedment.

Lot: Common auxiliary station equipment consisting of cooling watersystem, the power station drainage water system and draft tube/tail race

dewatering system.




Lot: Turbine junction boxes, switches etc. complete.

The above work shall be carried out on totality basis including the

incidental services mentioned in this document. Further the said work

shall be carried out in cooperation with the purchaser, and suppliers of

other equipment in a business like manner with utmost speed so as to

achieve overall economy and efficiency.

1.2. HYDRAULIC DATA

The hydraulic data and the other data regarding water conveyance

system is as follows:

A) LEVELS :

a) Minimum Draw Down level 140.50 mb) Full Reservoir water level 170.00 m

c) Maximum tail water level 35.00 m

d) Minimum tail water level 32.00 m

B) OPERATION HEADS

1. Maximum net head 117.00 m2. Minimum net head 84.00 m

3. Rated net head 106.00 m

4) Head variation 79.24 to 110.37%

5) Design Discharge 17.69 m3 /s

The turbine shall be designed based on the hydraulic data mentioned

above.




1.3. RATING REQUIREMENTS:

1) Output in turbine mode

The Turbine shall be so designed that Rated output of at least

15.625MW is developed at the coupling with generating under

the rated net head of 106 m

The bidder shall furnish information about maximum continuous

output at maximum net head of 117 m, at rated net head of 106 m

and at the minimum net head of 84.0 m in Annexure-V-5 and

data sheets of section V.

2) Turbine setting:

The Purchaser has tentatively chosen that the turbine setting

should be 0.63 m above the minimum tail water level. Further,the key dimensions / levels of the power house are tentatively

fixed based on the dimension of turbine and generator. For

example the levels such as the bottom of the draft tube, turbine

level, service bay level etc. The bidder shall examine this aspect

and give his recommendations about the precise requirements.

The proposed setting shall be such that adequate allowance is

provided under swing, shaft tube pressure pulsation,cavitationless performance, vibration and draft tube column

rupture etc.

3) Moment of inertia (GD2)

The moment of inertia shall be calculated and furnished. It shall

be by considering the maximum momentary speed rise, and

maximum momentary pressure rise

1.4 DESIGN REQUIREMENTS

i) The whole of the plant including all auxiliaries shall be

designed to give satisfactory service with designed

availability for a period of 50 years.




ii) Number of tripping :Ten (10) nos. per year

iii) Number of turbine : One (1) no. in five

runaway condition years life on an average.

iv) Closing of Butterfly : Every time the unit is

inlet valve stopped and brought to

standstill position.

v) The rotating parts of the unit shall be mechanically

designed so as to allow the continuous operation and the

stresses included in any part at maximum runway

condition shall not exceed 67% of the yield point of the

material of that part or 30% of the ultimate strength.

vi) The pressure containing parts of the unit for example theButterfly valve, the pipes and specials, the stay ring/spiral

case assembly and the guide vanes, shall be designed from

consideration of fatigue stresses induced due to cyclic

changes in pressure conditions. The guide vane regulating

mechanism shall be designed to have closing tendency and

minimum of lost motion and friction.

vii) The pulsation in power output in turbine operation shallnot exceed ±1.5% at full load output and ± 5% at partial

loads of actual rated power output.

viii) The maximum momentary speed rise as per IEC-41 clause

2.3.4.14 shall not exceed 1.5 times the rated speed.

ix) Maximum momentary pressure under most unfavorable

transient conditions accordingly to Clause 2.3.5.7 of IEC

4 1 shall not exceed permissible limit.

x) Whole of plant and equipment including the control and

protective equipment shall remain operative when

maximum credible earthquake occurs at site. Further, the

plant should trip and safely come to standstill when

earthquake of large magnitude occurs.




xi) The plant and auxiliaries shall be designed to operate

continuously for 12 months period without any offload

maintenance and to achieve high start-up reliability.

xii) The control scheme shall be so designed that in the event

of a collapse of the state grid system KAL HEP is

disconnected automatically.

xiii) When unit is in operation, the noise level in the turbine pit

liner 1 m away from shaft measured on any turbine floor

shall not exceed 90 dB (A) .

xiv) The generator and turbine bearing shall be so designed to

allow the unit to be frequently and quickly started.

Besides, the bearing shall be liberally designed such thatfull power output is available even if one of oil coolers of

any bearing is blocked continuously. In addition, the

volume of oil provided and circulating system shall be

such that none of the bearing would suffer any damage

during shutdown process in the event the unit is tripped

due to stoppage of cooling water / oil supply.

1.5 LAYOUT CONSTRAINTS :

The layout of power station is prepared with a view achieving over all

economy. The major dimensions and floor levels and the space provided

is given below

i) Width of the power station 15m

ii) Overall length of power station 32m

iii) Length of the service bay 10m

iv) Vertical distance between service bay

Level and the top of gantry rails. 11.6 m




B. After award of Contract:-

The Successful bidder (Supplier) shall be required to undertake the

following studies and / or calculations:

1. Optimisation of the turbine runner and the hydraulic passages.

2. Review studies and/or calculation mentioned above on the basis of data

obtained on completion of detailed design and supply the result.

3. Conduct FEM study to determine the stresses induced and the pattern of

concentration of stresses in major components of the unit such as turbine

runner, guide vanes, head cover, generator stator frame and the bearing

brackets.

4.

Computations of forces on overhangs, generator lower bracketfoundations, stator foundations etc. under most unfavorable conditions.

5. Dynamic analysis:

Studies to determine the dynamic behavior of the unit rotating parts,

bearing brackets and the forces which would be induced and transferred

to civil foundations shall be undertaken by computer simulations. The

studies should demonstrate the unit and the foundations are capable of

withstanding without damage the abnormal conditions during trip outsand during runaway conditions.

Dynamic analysis by computer simulation of the unit vibratory

characteristics should be carried out to determine the amplitude and

frequency of the hydraulically and mechanically excited vibrations

originating within turbine, generator and entire water passage system.

The frequency of these vibrations should be compared with each other

and the natural frequency of related components to determine whether ornot there would be resonance. The comparison should include critical

speeds, major machinery components, draft tube pressure pulsations,

frequency and magnitude of vortex shedding from runner, stay vanes

and guide vanes, the unit dynamic imbalance, runner hydraulic

imbalance earthquake etc. All these natural frequencies shall be checked




for adequate margin against predominant frequencies to avoid

resonance. Studies carried out in this regard shall be furnished.

The supplier shall duly analyse all cases of possible interferences of

different resonance frequencies and must ensure that abnormal vibration

shall not occur when the unit operating at any load from 60% to 100%

load turbine. Besides, such an operation shall not provoke power

pulsations at generator terminals.

1.7 Model Test of Turbine:-The performance guarantees i.e. output and

efficiency figures for turbine equipment being supplied under this

contract shall be on the basis of report of turbine model test already

carried out by the supplier for similar profile. The contractor shall

submit the test report along with calculations to prove the efficiency and

output of the turbine. If the calculation are agreeable to the purchaser the

model test will not be insisted and the turbine on the basis of data

furnish by the contractor will be accepted. If model test reports of

similar profile is not available with the supplier then model test shall be

carried out by supplier without extra cost to purchaser. In this case it is

assumed that price of mechanical lot is inclusive of price of model test.

1.8 DATA SHEETS

All data sheets appended to bidding documents must be completely

filled in by the bidder. The bidder shall specifically note incomplete

information or non supply of important information may result in

rejection of his bid.

1.9 DRAWINGS AND DATA TO BE SUBMITTED WITH BID

All drawings and data as per enclosed Annexure1.1 shall be submitted

alongwith the bid. The drawing and data shall be sufficient enough to

prove technical compatibility of the bid and shall not be limited to the

list of Annexure 1.




ANNEXURE 1-1

LIST OF DRAWING AND DATA TO BE SUBMITTED WITH BID

I- DRAWINGS

A) LAYOUT DRAWINGS PREFERRED SCALE

1. Plan and Cross section of Power house.

The drawing must show size of power

House required, the turbine Setting,

the excavation level below

the draft tube liner; turbine floor level

and generator floor level, Butterfly

Valve gallery level, the hook lift

requirement above the service bay

floor level and the required capacity

of the power station crane,

Drawing must indicate distance

between Butterfly valve center

and spiral case centre …….1: 100

2. Plan of the station at Butterfly

Valve gallery level showing the

equipment proposed and their




location. …….1:100

3. Plan of power station at turbine

floor level …….1:100

4. Plan of power station at generator

floor level. …….1:100

5. Plan of power station at operating

Level. …….1:100

6. Power station Control room

Layout …….1:100

7. Draft tube

Hydraulic Design of the draft tube and

Elevation & plan of the Draft tube showing

the exact provision of steel liner ……..1:20

8. BAR CHART

The bidder shall furnish bar chart showing supply, erection

testing and commissioning activities of major equipments of

power plant. The overall schedule shall suite the completion

period of 22 months.




SECTION - II

GENERAL REQUIREMENT




SECTION - II

GENERAL REQUIREMENT

INDEX

Clause

No.

Description Page No.

2.1.

2.2.

2.3.

2.4.

2.5.

2.6.

2.7.

2.8.

2.9.

2.10.

2.11.

2.12.

2.13.

2.14.

2.15.

2.16.

2.17.

2.18.

2.19

General Requirements

Limits of contract

Interchangeabiltiy

Engineering data

Drawings

Supply of Oils, grease/lubricants and other

consumables.

Manufacturing schedule and the progress

reports.

Design improvements.

Erection - Tools and Tackles and Spanners

Foundations and fixtures

Materials and workmanship.

Electrical Equipment.

Earthing.

Units.

Protective Guards

Storage at site.

Rating Plates, name plates and labels

Tests

Applicable standards

17

17

17

17

18

20

20

20

21

21

21

39

47

48

48

48

48

49

56




SECTION - II

2.1 GENERAL REQUIREMENTS:

The general requirements explained hereafter should be applicable to the

equipments to be supplied.

2.2 LIMITS OF CONTRACT:

Equipments furnished shall be complete in every respect with all

mountings, fittings, fixtures provided with such equipments and/or

needed for erection, completion and safe operation of the equipments

and are deemed to have been included. Further, these fittings, fixtures

and accessories shall be of the best standards and proven for use.

2.3 INTERCHANGEABILITY:

All parts shall be made to standard gauge in accordance with the normal

practice for the class of equipment concerned. All corresponding parts of

similar apparatus including spare parts shall be interchangeable.

2.4 ENGINEERING DATA:

The furnishing of engineering data by bidder shall be in accordance with

the provisions mentioned in the Technical specifications and the Data

Sheets annexed thereto. The review of these data by the purchaser and

his consultant will cover only general conformity of the data to the

specifications and documents interfaces with the equipments provided

under the specifications, external connections and of the dimensions

which might affect plant layout. This review by the purchaser shall not

be construed by the supplier, as limiting any of his responsibilities andliabilities for mistakes, omissions and deviations from the requirements,

specified under these specifications documents. All engineering data

submitted by the supplier after final design including review shall form

part of the contract documents and the entire work covered under these

specifications shall be performed in strict conformity.




2.5 DRAWINGS:

2.5.1 DRAWINGS AND DATA TO BE SUBMITTED WITH BID

Drawings and other data which is required to be submitted with the bid

is stated in the Annexure 1-1 of section I of this Volume.

These drawings shall include sufficient details to demonstrate fully that

the apparatus furnished shall conform to the provision and intent of

these specifications. Detail drawings or design data for the purpose of

checking the adequacy of the supplier’s design by calculations shall not

ordinarily be required but the purchaser reserves the right to call for

these in certain cases at his discretion. These drawing shall show

sufficient overall dimensions, clearance etc. required for assembling anddismantling and furnishing the space requirements of all apparatus to

enable the purchaser to determine the design and layout of the

installation and to decide the compatibility of the bid.

2.5.2 DRAWINGS AND DATA TO BE SUBMITTED AFTER AWARD

OF CONTRACT:

A) Drawings for approval:

The supplier shall furnish eight (8) copies of each of the

drawings, the list of which is given in respective specifications,

for approval of the purchaser. The methodology of submitting

these drawings to the officers of purchaser and/or to consultant

etc. shall be mutually agreed after award of contract.

The purchaser as far as possible will review the drawings

submitted by the supplier practicable within eight (8) weeks of their receipt. During the process the purchaser shall have the

right to call for additional clarification or to suggest changes,

which in the purchaser’s opinion, are required to conform the

equipment to the provision of the specification. The drawings

shall then be returned to the supplier along with comments and/or




2.6 SUPPLY OF OIL, GREASE/LUBRICANTS AND OTHER

CONSUMABLE:

Sufficient quantity of oil, grease, lubricants and other consumable

required to put the whole of the plant including auxiliaries into

successful operation shall be supplied (i.e. deemed to be included in

scope) without extra charges.

The quality and the grade of the oil, grease and/or lubricants and other

consumable to be used shall be from the locally available suppliers.

2.7 MANUFACTURING SCHEDULE AND THE PROGRESS

REPORTS:

The supplier shall submit to the purchaser his confirmed manufacturingand delivery schedules for all equipments within thirty (30) days from

the date of notification of award of contract. This schedule will not

relieve the supplier of the delivery and work completion obligations as

offered by him with the bid. The schedule shall be such as to meet the

requirement of onsite construction. This schedule may be updated, if

required, and the changes, if any, must be informed to the purchaser

every quarter. The schedules shall also include the materials andequipments purchased from outside.

Every quarter a report highlighting the delays, if any, and the actual

progress achieved shall be submitted.

For substantiating the progress report, video films and copies of the

photographs (in duplicate) shall be supplied.

2.8 DESIGN IMPROVEMENTS:

The purchaser or the supplier may propose changes in the specifications

of the equipment or the quality thereof and if the parties agree upon any

such changes, the specification shall be modified accordingly.




2.9 ERECTION-TOOLS AND TACKLES AND SPANNERS:

A complete outfit of erection tools and tackles, gauges, slings, other

lifting devices, instruments and all other appliances required for the

assembly, erection, dismantling and maintenance of the plant should be

supplied. Spanners and wrenches shall fit the nuts and bolts used in the

plant.

2.10 FOUNDATION AND FIXTURES:

Foundations related to various equipments shall be prepared by the

purchaser on the basis of design data furnished by the supplier in line

with civil construction schedule. However, the supplier shall supply all

fixtures necessary for proper erection of embedded parts. If requested by

the purchaser, the supplier shall assist the purchaser in evolving special

designs and criteria for civil foundation works of the pump-turbine and

generator-motor unit. All supports, fixtures etc. needed for assembly,

erection, testing and commissioning including that for field tests shall be

prepared by supplier at his cost.

2.11 MATERIAL AND WORKMANSHIP:

2.11.1 GENERAL

All parts shall be manufactured true to drawing dimensions. All

tolerances shall be defined on the suppliers drawings for both

manufacturing and installation purposes. Holes shall be drilled full size

or under size and reamed during shop assembly. Punched holes will

only be permitted in plates 20 mm or less in thickness provided all such

holes are subsequently reamed full size during shop assembly.

The materials used in the construction of the plant shall be new of high

quality and selected particularly to meet the duties required of them.

The material specification shall be indicated in supplier’s detailed

drawings.




The use of materials liable to be attacked by termites or other insects

shall not be allowed. All workmanship shall be of the highest quality

throughout to ensure smooth running without vibration and noise under

all possible operating conditions. The design, dimensions and materials

of all parts, shall be so chosen that the stresses to which they may be

subjected shall not render them liable to distortion or damage under the

most severe conditions encountered in actual services.

Materials and workmanship shall conform to the latest editions of the

relevant standards.

2.11.2 PIPING:

All pipes and fittings (adequate number to be approved by thepurchaser), valves, drain plugs/cocks, test plugs, sight flow indicators,

meters etc. shall be provided so as to allow the operation and

maintenance of the system with ease.

All piping shall be clean inside and where ending in open connections

for other works, the piping shall have the ends capped for protection.

Valves shall be easily accessible and gauges and other operating or

indicating devices shall be located so that they can be convenientlyoperated or read from the floor walkways. Valves shall be suitable for

the services intended. Either a blind end flange or a pipe shall be

provided wherever necessary to protect valves.

Where piping systems must be disconnected for servicing, flanges or

unions shall be provided and the piping, valves and joints shall be

arranged for minimum disturbance or interference with other parts

during operation.As far as possible, the pipes shall not be embedded but shall run in

trenches or shall be suitably supported by hangers, brackets, hooks,

pedestals, or any other support suited to the requirements, care being

taken to avoid vibration at the supports. An adequate allowance for the

expansion of pipes under service conditions shall be made. Each drain




removal in the course of operation, shall be made of corrosion resistant

steel or bronze.

Spring type washers will not be permitted where they may damage any

protective castings. Special tools, wrenches and devices found to be

necessary for the completion of the work should also be provided under

this contract.

2.11.4 FORGING:

All highly stressed forgings shall be subjected to examination internally

for the detection of flaw and heat treatment for the relief of residual

stresses. Particulars of the heat treatment proposed for all forging shall

be submitted to the purchaser.

2.11.5 CASTINGS:

The casting shall not contain damaging defects and shall be

satisfactorily cleared before use. The surfaces that are not machine

finished and which will be exposed after their final installation shall be

such that grinding at the site will not be required before painting. Thepresence of defective material shall be determined and it shall be

removed down to sound metal.

The cast parts shall be homogeneous and free from excessive non-

metallic inclusion. An excessive concentration of impurities or a

separation of the alloy elements in the critical points of a cast part shall

be sufficient reason for its rejection.

The casting of the main parts, including all those subject to hydraulicpressure and all castings which undergo a major repair, shall be tested

using radiographic, ultrasonic, dye-penetration, magnetic particle or any

other standard non-destructive test method. The expenses incurred on

such tests shall be to the suppliers account. In case of bus duct only

10% radiography of enclosure shall be done.




Minor defects or imperfections, which definitely do not affect the

strength or utilisation of the cast parts, may be repaired by welding,

according to the accepted practice for the repair of such parts.

Thickness and other dimensions of the cast parts shall agree

substantially with the dimensions shown on the drawing and shall not be

reduced by shop or casting practices to such extent that the effective

strength of the cast parts shall be less than the stresses allowed by these

specifications.

Use of cast iron for parts subjected to tension or impact shall not be

permitted without the approval of the purchaser.

2.11.6 WELDING

Supplier shall specify clearly on all relevant drawings, the amount and

type of material for each type of weld, supplier shall also provide

detailed drawings showing joint preparation required for each type of

welding to be carried out on site and at supplier’s works.

The parts to be joined by electric welding shall be cut precisely to the

correct size by methods suitable for the type of weld to be used and to

allow proper penetration and good fusion on the weld with the basemetal. The cut surface shall not have visible defects such as scales;

superficial defects caused by shearing or torch cutting operation or any

other damaging defects. The surfaces of the edge to be welded shall be

free from rust, oil, grease and other foreign matter. All welds exposed

to water flow shall be ground to a smooth and even surface flushed with

the adjacent plate.

Supplier shall indicate on the detailed drawings, the type, sizes andmaterial of electrodes he proposes to use for shop and/or field welding.

Unless otherwise stated, all non-destructive tests shall be carried out.

All major welding and all welding carried out on tanks and vessels,

which will contain liquid under pressure or compressed air shall be

subjected to 100% radiographic examination. In those cases where it is




impossible to carryout radiographic inspection, or otherwise stated in

specifications, it may be replaced by ultrasonic examinations or any

other non-destructive test systems.

2.11.7 SURFACE TREATMENT AND PAINTING:

1. GENERAL

Where necessary the work shall be painted or treated with protective

coating to protect them from corrosion and to neat and pleasing

appearances. This work shall comprise the surface treatment, priming

and application of paint or metallic coatings in the supplier’s workshops

and at the site including all paint repair work becoming possibly

necessary.Every possible attempt shall be made that the design of the equipment is

such that all surfaces can be finish coated or recoated after erection at

the site.

Unless otherwise specified, the coating and painting shall be carried out

in accordance with the latest International Standard (Protective coatings

for steel structures, directions) or another equivalent approved standard.

All priming and painting material shall satisfactorily fulfil therequirements imposed by the site conditions (considering also possibility

of extended periods of storage at site) as well as the stresses to which the

respective equipment is subjected during operation of the works Shade

of the finishing coatings shall be as per the standard colour tables at the

choice of the purchaser.

Each coat of primer and paintings shall be compatible with the previous

and subsequent coats. All pigmented primers and paints, which will be

used for priming and painting at the site shall be delivered in original

and sealed containers packed by the supplier.

The supplier shall supply full details regarding the extent by which sand

blasting; priming will be carried out in his workshops (or his sub-

suppliers as the case may be), at the site and after erection.




All working of the material (e.g. welding, drilling, grinding) shall be

completed and surface defects (e.g. weld splatter, burns, cracks, surface

laminations and pitting), likely to be detrimental to the protective

coating shall be removed before surface preparation begins.

As regards welding joints, these shall be covered with one coat of

appropriate primer shortly after welding wherever possible. Otherwise

they must be cleaned with a steel brush before applying the first primer

coat.

3. PRIMER, FINISHER AND PAINT APPLICATION

Before the application of the primer all sand blasted or otherwisemechanically created surfaces shall be subject to thorough cleaning

process during which all dirt, dust, grease, moisture etc. is removed so

that the primer is applied on suitable surfaces. Clean cloth and pure

dissolvent shall be used for this process.

The primer may be applied by airless spray gun, roller or by brush.

All subsequent coats of paint shall be applied using airless spray

equipment, unless otherwise recommended by the paint supplier or

approved by the purchaser and or consultant.

Where the use of airless spray equipment is found impracticable, the

supplier must be prepared to use brush application at no additional cost

to the purchaser, such application being to the approval of the paint

supplier and the purchaser.

The paint supplier’s instructions shall be followed implicitly withrespect to the method of application of the paints, the drying time

between coats and the temperature of the material being painted, where

ambient temperature, relative humidity or dew point will affect the

drying or curing of paint, the manufacturer’s recommendations shall be

followed.




Unless specifically recommended otherwise by the paint supplier or

approved by the purchaser, not less than 24 hours, not more than five

days shall lapse between priming and successive coats of paint.

Each coat shall be free from runs, drops, pin holes, waves, lops, sag and

unnecessary brush marks.

Particular care shall be taken to provide adequate paint film cover on

corners and edges, nuts and bolt heads.

Equipment contained in cubicles, cabinets or similar enclosures shall be

painted as if it were exposed to view and the inside surface of the

enclosures shall be painted semi-gloss white. In sheet metal enclosures

where otherwise the surface would not be protected against corrosion(e.g. between the surfaces of spot welded joints and behind stiffening

channels), such surfaces shall be coated before assembly with an

approved spot welding primer after preparation of the surface in

accordance with the paint supplier’s instructions.

All paint shall be delivered to the point of use in unopened containers

bearing the manufacturer’s label which shall include, where appropriate

for special systems, date of manufacture, batch number and instructions.All paint shall be supplied in the ready-mixed condition and except to

comply with the supplier’s direction, mixing of paint by the supplier

shall not be permitted.

Machinery paint may be thinned, if necessary to permit satisfactory

application, but the amount of thinner shall be kept to a minimum.

Special attention has to be given to the two-pack coating. The

application of these materials is no problem if the specification is strictly

followed. For a perfect application the following important and

generally valid conditions apply:

The prime coating should be applied immediately after or at least on the

day of blasting (exception only in air conditioned rooms).




After the mechanical treatment but before the top coating is applied, the

prime coating has to be cleaned (grease, oil and other impurities) with

solvents and/or hot stream.

- Application temperature for two-pack epoxy-resin coating at least

5°C

- Surface temperature minimum 5°C above dew point.

- Maximum atmospheric humidity: not higher than 75%

- The proportion of mixture for two component products is to be

strictly followed.

- Waiting times between coatings to be observed according to

specification.

- For multilayer it is advisable to change the shade of colour (forlater abrasion). Otherwise abrasions have to be checked by

measuring film thickness.

- Edges have to be pre coated.

- Not to prime a strip of 150 mm beside the planned site welds

(especially important for zinc rich primers.).

- Prior to the top coating, the prime coating has to be repaired

carefully.

4. GALVANISING:

All drilling, punching, tapping, cutting and bending of the parts shall be

completed and all burrs removed prior to galvanising.

Galvanising shall be applied by the hot dipped process and shall consist

of the smooth clean zinc coating free from defects and of uniform

thickness. Original blast furnace raw-zinc (minimum purity 98%) shallbe used. The zinc coating shall weigh not less than 600 g/m² of area

covered. Sheardizing or other alternative process shall not be used

without the approval of the purchaser and/or consultant.

Material on which galvanising has been damaged shall be re-dipped

unless, in the opinion of the purchaser, the damage is local and can be




repaired by applying a coat of galvanising repair paint where such repair

is authorised the damaged area shall be cleaned by wiping with clean

rags saturated with mineral spirits or xylene followed by wire brushing.

After wire brushing, the area shall be re-cleaned with solvent to remove

residue and shall be given a minimum of two coats of zinc primer

containing not less than 98% (by weight) of metallic zinc in the dry film,

which shall have a total thickness of not less than 60 micrometers.

Galvanised surfaces should be kept apart in storage and transport. If this

is impossible, they should be treated by dipping in a 10 to 18% solution

of chromic acid, which should produce a coating of 12 micrometers.

This coating must be removed before any painting is attempted.

5. METAL SPRAYING:

Subject to the approval of the purchaser where an item is of a size or

shape to render hot-dip galvanising impracticable, zinc spraying or other

approved method of coating may be adopted.

Metal spraying of surfaces shall comply with the following procedure:

Surface preparation prior to spraying shall be dry grit blasting to a

standard approved by the purchaser and/or consultant.Immediately after grit blasting, the surface shall be cleaned of any traces

of blast products on the surface and in pockets, pits and corners by

brushing with clean brush, blowing with compressed air or vacuum

cleaning.

The surface shall be coated with the metal spray before discolouration

occurs. In the event of the surface becoming contaminated e.g. with

rust, oil or dirt between blast cleaning and applying the metal spray, it

shall be re-cleaned by repeating the above procedures. Care shall be

taken to have as little roughness as possible on the sprayed surface.




The material can only be applied with a special machine. Standard

application is one coat. Because of the lack of solvents in the painting

material, there is no danger of pores. Total film thickness: 360

micrometers.

REMARK: Condensation zones where the colour is not visible from

outside may be coated with epoxy coal tar.

8. NON-CORROSIVE MATERIALS

Normally highly alloyed stainless steels, Ni:Cr. 4:13 (can be corrosive if

soiled) and bronze e.g. red brass are not to be coated.

It is important, however, that the contact areas stainless steel/normal

steel are carefully protected by coating, also a stripe of the non-corrosivematerial, otherwise an amplified corrosion may occur (Contact

corrosion).

Machine with long rest periods (e.g. pumps) are exposed to increased

localised corrosion similar to ‘pitting’ (localised corrosion) usually on

the base materials when the coating is porous and damaged.

EXCEPTION: If a stainless steel part required a coating due to reasons

such as photographing or decoration, a water and oil resistant syntheticresin primer should be applied. Such coating has to be especially

required by the purchaser.

9. ZONES WETTED BY CONDENSATION:

The main strain for zones wetted by condensation is the permanent

rewetting, i.e. interchange: wetting - drying.

The visible surfaces are less stressed. However, surface quality and

appearance (shade of colour) require a high standard of material. Gloss

and semi gloss finishes facilities cleaning.

Due to practical reasons visible and invisible (dry) surfaces are not

differentiated. The same applies for visible surface of stainless

materials.




The coating system is set up as follows:

Prime coating:

One layer of two-pack zinc rich epoxy primer to avoid ‘under rusting’ if

the topcoat is damaged or porous. Film thickness 60 micrometers.

Intermediate Coating:

One layer of two-pack micaceous iron oxide epoxy paint (two coats if

exposed to condensation). The micaceous iron oxide in lamellar from

embedded in the epoxy oxide is a perfect pore protection and has

excellent adherence properties for the top coating. Film thickness: 60

micrometers,

Top coating:

One coat:Either polyurethane acrylpolyol micaceous iron oxide coat of 60

micrometers (recommended for outdoor coating providing a mat glossy

surface).

Or polyurethane top coating of 60 micrometers with a glossy surface,

usually applied for indoor coatings. The polyurethane based topcoats

have very good abrasion and mechanical resistance in addition to a

proven corrosion protection and excellent colour retention.Total film thickness: 180-240 micrometers.

REMARK: Parts covered with epoxy coal tar on the waterside should be

coated with the same material on the condensation waterside if the shade

of colour is not important.

10. OIL WETTED SURFACES:

For Oil tanks, bearing casings, servomotors etc. a standard coat as a one

pack synthetic resin primer is sufficient. This coat is oil and water

resistant up to 150°C. The first primer is applied before the tightness

test and the second coat is applied after assembly. The total film

thickness: 80 micrometers,




11. COATING OF MACHINED SURFACES:

Machined surfaces require a two-pack epoxy resin zinc chromate or zinc

phosphate pigmented prime coat to improve adhesion to the base

material. A standard top coating may then be applied, depending on the

strain the parts are exposed to total film thickness: 120 - 160

micrometers.

REMARK: Generally sand blasting after machining (if possible) is

preferred because of the adhesion of the paint. Sand blast surfaces may

then be coated in the normal manner.

12. BLANK SURFACES

These surfaces are only to be protected for transportation and temporary

storage with a soluble lacquer.

13. PIPEWORK

WATER PIPES

All such pipes, except those of corrosion resistant material shall be blast

cleaned and be coated by dipping in acid free hot bituminous compoundto give an acceptable finished coating thickness.

Ends of pipes and tubes subject to weld joining at the site shall be left

uncoated over a distance of approx. 100 mm. After site welding the

erection welds shall be coated with 2 layers of zinc-rich primer

containing not less than 95%(by weight) of metallic zinc in the dry film,

which shall have a total thickness of not less than 60 micrometers.

Finishing of the ends of pipes and tubes interior shall be by a layer of zinc rich chlorinated rubber paint.

The exterior of small pipes shall be carefully cleaned and pickled and

coated with 2 layers of zinc-rich chlorinated rubber paint.

Exterior surfaces of pipes and tubes, except those of corrosion resistant

materials shall be primed with three layers of red lead paint on




chlorinated rubber/synthetic resin basis (total minimum thickness of the

dry film: 100 micrometers). Un-insulated and unwrapped pipes and

tubes shall receive two subsequent layers of finishing paint on the same

basis (total minimum thickness of the dried finishing coats: 60

micrometers).

OIL PIPES

Both the interior and exterior shall be thoroughly cleaned and pickled

and rinsed very carefully to an approved method. The exterior surfaces

shall subsequently receive two layers each of oil resistant priming and

finishing varnish or enamel,

A corrosion prevention compound shall protect the interior of fuel

carrying pipes.

AIR PIPES

Same treatment and painting as for the water carrying pipes. The

purchaser will decide on the finishing shades at a later date.

AIR DUCTS

External surfaces shall be coated with 2 layers each of priming and

finishing paint.

14. CUBICLES AND CABINETS

FOR INDOOR INSTALLATION

After careful sand blasting all cubicles and cabinets shall be given two

priming and two finishing coats of varnish or enamel which in case of

those carrying oil or liable to oil vapour exposition shall be oil resisting.

A minimum dry film thickness shall be 100 micrometers in total.

The insides of cubicles and cabinets where condensation is liable to

occur shall be coated with four layers of an approved anti-condensation




composition. Other inside surfaces shall be coated with at least two

layers of varnish of semi glass white.

External surfaces of cubicles and cabinets shall be given to supplier’s

standard primer and machinery enamel or appropriate enamel for

cubicles being used indoors for electrical equipment. All cubicles being

located in one row must be painted with the same shade.

FOR OUTDOOR INSTALLATION

These cubicles and cabinets shall be given after careful sand blasting

and hot dip galvanising coat inside and outside. After etching these

should receive two layers each weather resisting varnish or enamel.

15. STEEL CONSTRUCTIONS

INDOOR

Same shall be thoroughly sand-blasted and provided with (two hours

later) three layers of red lead primer on chlorinated rubber/synthetic

resin basis (total minimum dry film thickness: 100 micrometers.)

Finishing shall be by 2 respective coatings on the same basis (totalminimum dry film thickness of finishers: 60 micrometers).

Areas subject to oil and grease shall receive four layers of oil resistant

priming and finishing (varnish or enamel). This shall apply in particular

to all transformers.

OUTDOOR

After careful blast cleaning with an approved method and cleaning of

the surface after this process, all steel structures shall be heavily hot dip

galvanised.

16. WORKSHOP EQUIPMENTS, PUMPS, COMPRESSORS ETC.

Treatment as per the supplier’s practice, and coating with the supplier’s

standard primer and machinery plant.




17. PLATFORMS, HANDRAILS, COVER PLATES, TRENCH

COVERS, ACCESS LADDERS ETC.

All gratings shall be heavily hot-dip galvanised. Aluminium alloy

chequered plates need no treatment and protection.

Ferrous chequered plates shall be heavily hot dip galvanized.

Handrails shall be heavily hot dip galvanized. These should after

etching receive 2 layers of oil resisting varnish or enamel.

18. PARTS IN CONCRETE

The surfaces shall be cleaned from mill scale, dirt, oil, grease and other

residues and shall be covered before leaving supplier’s premises with a

substantial coating of Portland cement wash or other proprietary coating.For parts in concrete, it is important that the zone between visible surface

and zone in concrete, a stripe of approx. 0.5 m of the concrete be coated,

along the visible surface.

Components under high pressure (penstocks or spiral cases) touching in

concrete should be sealed additionally.

2.11.8 BALANCINGFor small rotating machinery all rotating parts and assemblies shall be

well balanced both statically and dynamically at the supplier’s works.

The supplier shall rectify any out of balance that may occur during

erection at site. Over dimensioned and heavy rotating machinery shall

be statically and accurately balanced at the point of installation.

2.11.9 DOWELLING

At all stages of assembly, where accuracy of fit has to be assured

on-site, dowel holes shall be provided with dowels to assist

reassembly and load resting if needed.




The alternating current (A.C) motors of rating ≤120kW shall be

provided with direct on line starter at supply voltage of 400V and

those of rating > 120kW shall be provided with star/delta starter.

Rated power of motors shall be guaranteed at 85% rated voltage

and 95% of rated frequency with closed air cooling according to

IEC standard with interchangeable possibility.

The pump capacities and the rating of the driving motors shall

have liberal margin over the requirements. Motors shall be drip

proof.

All pumps shall be designed and constructed to ensure quiet and

satisfactory operation without undue noise or vibration under all

conditions of discharge and pressure. Centrifugal pump casings

shall be designed to produce smooth flow with gradual changes

in velocities. In addition, the pumps shall be easily removable

and replaceable. Suitable gaskets shall be provided for all pipe

joints to ensure that they are leak proof. If any strainers are

required with the pumps, these shall be included in the bid and be

duplex type or with by pass to enable periodic cleaning.

All pumps shall be complete with the necessary piping, both onthe suction and delivery sides and with all fittings suited to the

size and duty of the pump. Adequate number of valves as stated

earlier shall be furnished with each pumping unit to suit its

operation and maintenance. Wherever necessary, pumps shall be

provided with suitable flow meters or flow indicators and

pressure gauges to measure the discharge and the pressure

delivered by the pumps. Suitable eye bolts or lifting lugs shall beprovided on each pumping set to facilitate handling.

2.12.3 ELECTRIC MOTORS AND MOTOR CONTROL GEAR

All motors furnished by the supplier, for driving the unit

auxiliaries and other apparatus shall be directly coupled to the




apparatus driven and shall be suitable for operation on purchasers

power supply. All motors to be supplied shall be energy efficient

motors.

The enclosure of each motor shall be of the type best suited to theservice conditions of the motor and shall be subject to the

approval of the purchaser in every case. The motor shall

generally conform to the relevant Indian or IEC or other

equivalent standards. The insulation shall be moisture, oil, oil

vapour, drip proof and the motors shall be entirely suitable for the

operation in the tropical climate conditions prevailing at site with

100% humidity (degree of protection IP 54 or as applicable).

Motor shall be provided with varnish cambric or glass insulation

class F and shall be used for connections from the windings to the

terminals. All motor terminals shall be of stud type and totally

enclosed.

The capacity, speed and torque characteristics of the motors shall

be suitable for the starting and operating requirements of theassociated apparatus. The supplier shall furnish necessary

starting, protective and control gear with each motor.

Instantaneous and thermal overload protection shall be provided

for the motors together with remote indication of the operation of

the protective gear, wherever necessary. In the case of essential

motors stoppage of which would result in serious damage the

thermal overload protection devices shall be arranged to givealarm only, without disconnecting the motors. Red and green

indicating lamps shall be furnished for indication of the closed

and open positions respectively of motor contacts. The control

and indication equipment shall be suitable for operation with 220

V DC supply.




Special type of motors, not adequately covered by the

specification may be offered for any special application, but these

shall be subject to the approval of the purchaser.

2.12.4 SMALL WIRING

All small electrical wiring of various equipments, panels, etc.

shall be completed at the supplier’s work as far as possible. All

small wiring shall be arranged neatly into flat or rectangular

groups and shall be adequately supported with cleats etc. The

small wiring shall be so arranged as to reduce the number of

bends or crossing to a minimum. There shall be no splices in the

wire and all connections shall be made at the terminal studs orterminal blocks. Similar circuit shall be arranged to terminate as

far as possible on adjacent terminals to facilitate grouping and to

minimise the number of interconnecting cables. Secondary or

control wiring including leads from the current transformers,

temperature detectors, alarm contacts, speed and pressure

switches etc, shall be enclosed in conduits and shall be carried to

dust and water proof and oil tight cabinets located convenientlyfor connection to the control cables.

Pressure circuits shall be suitably protected so that failure of one

circuit shall not cause the progressive failure of adjacent circuits.

Alternating current circuits, direct current circuits, shall be

grouped separately and the wiring of each of these groups shall

preferably be segregated.

For the purpose of easy identification, tracing and reconnectionthe wiring shall be colour coded according to relevant

international or IS standards and shall be fitted near the terminals

with ferrules or such other cap indelibly marked with the

identification number corresponding with that of the associated

terminal blocks. When an electrical circuit is extended to several




pieces of equipment necessitating sectionalising of circuit wiring

at the terminal blocks of the corresponding equipments common

identification numbers shall be used for the designation of the

circuit at all the terminal blocks and connections. The terminals

and circuit designation for all wiring shall be subject to the

approval of the purchaser.

All small wiring shall be switchboard type, single conductor,

tinned annealed copper wire, PVC insulated cables as per

relevant Indian or International standards, insulated with

varnished cambric, which has proved its utility in tropical region

against hot damp and moist climatic conditions and wiring

complying with the relevant international standards. All small

wiring shall have oil and oil vapour proof insulation. The sizes

of the wiring for different circuits shall be so chosen as to provide

ample margin for the purposes intended and shall be subject to

the approval of the purchaser.

2.12.5 TERMINAL BLOCKS

Terminal blocks shall preferably be made of suitable moulded

plastic material and shall be provided with brass stud inserts for

terminating the outgoing end of the cubicle wiring and the

corresponding wiring of the incoming end. Provision shall be

made on each block for holding 15% extra connections.

Easily removable shrouds, moulded from transparent dielectric

material, shall shroud all blocks. The terminal block shall be of

disconnecting type and suitable for max. 1000 V service and

dielectric test of 2000V.

Sufficient space for receiving the control cables inside the

switchboard at the bottom of the switchboard cubicles and

mounting arrangements for the terminal glands shall be provided.




quantity or state under all conditions of operations and any error

due to change in the ambient temperature, over the entire range of

temperatures obtainable at site, shall be kept to a minimum. The

instruments shall be provided with all the auxiliary appliances

and any special tools required for their maintenance.

MKS (meter-kilogram-seconds) units shall be used for marking

the instrument dials. The range shall generally be such that the

normal operating values are indicated in the middle third of the

scale.

All electrical instrument coils shall be designed for continuous

operation on at least 120 percent of the full rated current and

voltage of the instruments. The instrument coil rating shall be co-ordinated with those of the associated instrument transformers.

The VA burden of instrument coils shall be as low as possible,

consistent with the best modern design.

Electrical indicating instruments shall comply generally with the

requirements of the Indian/IEC or any other International

Standards and shall be of the accuracy specified in relevant

sections.Recording instruments shall be of the strip chart type with chart

scales having a suitable width. The chart shall be gear driven by a

self-starting synchronous motor wound spring device having

ample torque even at reduced voltage and with at-least 8 hours

spring reserve under all normal conditions of operation. The

recording instruments shall be of withdrawal type for easy access

to maintenance work. Sufficient number of chart rolls, recording

ink for five years of operation and any special tools required for

the maintenance of the instruments shall be furnished with each

recorder.

Integrating watt and VAR hour meters shall comply generally

with the requirements of the international standards.




Instruments provided with contacts shall have contacts suitable

for 230V, A.C. or 220 V D.C. circuits.

All instruments shall have as high accuracy as possible consistent

with best modern design. The construction of instruments shall

be mechanically sound and shall ensure permanence in the

accuracy. The limits of error for different instruments shall be

stated in the bid and their accuracy classification, where

otherwise not specified, shall be subject to the approval of the

purchaser. All instruments shall be tested in accordance with the

requirements of the standard, wherever specified. In cases where

no specific standards are mentioned, the supplier shall submit the

list of the standards in accordance with which the instruments areproposed to be manufactured and tested and these shall be subject

to the approval of the purchaser in every case.

The instruments shall be capable of withstanding the following

tests viz., effect of shock, effect of vibration, effect of humidity

and dielectric tests of 2000 V to ground for one minute in

accordance with relevant standards.

2.12.7 FLOW RELAYS

Flow controllers, used throughout the works shall be equipped

with adjustable contacts suitable for 220V D.C.

System designed to change position on a decrease in flow below

predetermined value.

2.12.8 LIMIT SWITCHESAny limit switch shall be entirely suitable for its specific

application. Particular attention shall be paid to potentially

harmful environmental conditions, including water, oil, dust, dirt,

temperature variations and differential expansions, where

switches operate through linkages. Precautions shall be taken to




eliminate variations of setting and incorrect operations resulting

from wear or tolerance. Operating voltage shall be 220V D.C.

2.12.9 CONSTRUCTIONAL REQUIREMENTS FOR CUBICLES

AND PANEL BOARDS

Switch boards, control, relay and metering panel shall be of

robust, industrial type design and manufacture, formed of a steel

frame and covered with smooth steel plate. The steel plate shall

be sufficiently thick and properly stiffened to prevent distortion.

If required, flush mounted hinged steel doors with latches shall be

provided; doors shall be of the lockable type by means of

approved key locks. The key lock shall be of the same type forall panels.

All cubicles shall be fully enclosed and protected according to the

protection class given in the specification. The lowest degree of

protection shall be IP 44.

The frames of the cubicles shall be designed to permit firm

anchoring on the floor.

The frames shall permit easy erection and allowance shall bemade for extension of the cubicles by additional similar ones.

Supplier’s supply shall include all necessary mounting brackets,

framing, foundation bolts and respective embedded metal to

permit proper installation of the cubicles.

2.13 EARTHING

The Supplier shall provide earthing terminals on all the equipmentssupplied under the contract and shall connect the earthing conductors to

these terminals as approved or directed by the purchaser.

The Supplier will provide the earthing conductors from the station

earthing bus to the equipment. Supplier shall do equipment earthing.

The Supplier shall provide suitable test terminals at convenient points




of the equipments being supplied to enable periodic testing of the

receptivity and insulation level of the equipments. Purchaser will

provide earth mat and mild steel flats. Supplier shall provide suitable

earthing terminals with bimetal clamps, washers, nut bolts, lug etc.

suitable for both connections.

2.14 UNITS

According to the latest edition of the relevant Indian and/or IEC

publications shall be used for this contract. For the purpose of

design/calculations, SI Units shall be used.

2.15 PROTECTIVE GUARDS

Suitable guards shall be provided for protection of personnel on all

exposed rotating and/or moving machine parts. All such guards with

necessary spares and accessories shall be designed for easy installation

and removal for maintenance purpose.

2.16 STORAGE AT SITE

The supplier shall furnish complete instructions regarding the storage of

the equipment at site. If at any time after the receipt of equipment at

site, supplier or his representative desires to draw the attention of the

purchaser to the conditions of storage, which in his opinion might affect

the state of the equipment stored, he shall do so in writing to the

purchaser. Periodical inspection of stored items shall be the

responsibility of supplier.

2.17 RATING PLATES, NAME PLATES AND LABELS

A rating plate of non-corrodible material metal sheets shall be attached

to major and auxiliary item of equipment supplied. This plate shall be

permanently engraved with the designed full load ratings, serial number,




type, number, date of manufacture and other identification deemed

necessary. Where necessary, diagram plates shall also be supplied.

A name plate shall be provided to identify the service of major items of

plant supplied. The purchaser shall approve the identifying description.

Devices shall be identified by name plate on both front and rear of all

desks, panels, cubicles etc.

Names plates or labels shall be manufactured of stainless steel or

aluminium alloy with engraving of contrasting colour or alternatively for

indoor use of transparent plastic material with lettering engraved on the

back and filled with enamel. These shall be in English language only.

2.18 TESTS

In accordance with stipulations of General Conditions of Contract and

Special Conditions of Contract the test shall be performed. Brief details

of tests are as follows but shall not be limited to the same.

2.18.1 GENERAL

Inspection and testing of the equipment shall include all

inspections, tests, checks, procedures etc. Whether mechanical,hydraulic or electrical as required to ensure that the equipment

supplied meets the requirements of the technical specifications.

The tests include, but are not limited to the following.

- Chemical analysis of materials

- Destructive and non-destructive tests of materials

- Check and examination of welds

- Check of fits and assemblies

- Dimensional checks

- Inspection of paints and coatings (thickness and porosity)

- Hydrostatic pressure and tightness tests

- Balancing tests




- Shaft run-out tests

- Electrical tests

- Running tests (inclusive measurements of vibration and

noise levels).

- Functional tests

- Performance tests

- Load and overload tests

- Load rejection and load taking-up tests

- Acceptance tests (prototype output and efficiency tests)

- Type tests if specially required

The technique, equipment and instrumentation to be used for

these tests, checks, inspections, examinations etc. shall generally

be in accordance with the relevant internationally accepted

standards, rules or codes mentioned in except where specifically

mentioned in the technical specification.

If in the purchaser’s and/or consultants opinion instruments,

apparatus, devices etc. used by the supplier (or sub supplier) need

calibration or re-calibration then such instruments, apparatus,

devices etc. shall be calibrated at the supplier’s cost by anindependent authority or institute subject to approval by the

purchaser.

2.18.2 RANDOM SAMPLE TESTS

These tests are to be carried out on random samples from a lot of

equipment, parts or material. The purchaser and / or consultant

shall do the choosing of samples to be tested, parts etc. and thecomplete lot of equipment be presented for this purpose. The

number of samples taken will be either at the discretion of the

purchaser and/or consultant, particularly for small lots, or shall

conform to the generally accepted rules and standards of

statistical testing. The whole lot, of which the samples have been




taken, shall be considered satisfactory if none of the sample

tested has failed. Should any one of the samples fail, even in any

one test, the following shall apply.

a) SMALL LOTS: All pieces shall be fully tested.

b) LARGE LOTS: A second set of samples, identical in

number to the first one, shall be chosen and tested. If the

set passes all tests satisfactorily, the lot shall be considered

to be accepted. If again one or more sample fails in the

tests, either the whole lot shall be rejected of all pieces of

the lot be fully tested individually. The decision as to

which of the two alternatives shall be adopted shall be

with the purchaser.Pieces of lots which have been declared non acceptable and

samples which have failed in test must be marked immediately

and must not be presented for test again.

2.18.3 TESTS AT SUPPLIER’S WORK

Before any material, equipment, aggregate, apparatus etc. is

packed or dispatched from the supplier or sub-supplier’s works,all tests, inspections, checks, examinations etc. required by the

relevant and international accepted standards, rules or codes shall

be carried out as far as practicable and agreed in the

specifications.

All equipment, materials, aggregates, apparatus and other parts of

components of the works to be tested, inspected, checked,

examined, etc. at the supplier’s or sub-supplier’s works shall beproperly accessible for testing and inspection work. There shall

be no interference or disturbance from other shop activities when

conducting the tests and inspections.

It shall be understood that all equipment materials, aggregates,

apparatus and other parts or components will be adequately




shielded and protected against weather whilst being tested,

inspected, checked and examined.

Parts and components shall be assembled to the fairest possible

and agreed extent and dimensional checks shall be performed on

all major assemblies, sub-assemblies, parts and components

especially when close tolerance and fits are being involved

(tolerance of shafts, clearance between stationery and moving

parts, connecting dimensions for the assembly with other

elements and supplies, combined functioning of electrical

equipment etc.)

Components and parts to be weld assembled at the site, shall be

tag welded in the shops to permit visual and dimensional check of the fits and transmissions. All such components and parts shall be

match marked properly to ensure correct assembly and welding at

the site.

If dimensional checks show discrepancies in measurements,

which may affect the fit transition clearance, assembly or

dismantling of the respective part or component, immediate,

proper, and workman like correction or modification is a must.Such correction or modification shall, however, in no way lead to

sacrifice with respect to reliability of operation or inter-

changeability and shall be performed only after the agreement of

the purchaser and/or consultants has been obtained. If the

correction or modification cannot be carried out in accordance

with the terms mentioned above, the part or component

concerned may be subject to rejection.

Doubtful, used, weak and faulty materials or products will also

become automatically liable for rejection.

Shop testing shall also cover the hydrostatic pressure testing of

equipment which can be finish assembled in the supplier’s or his

sub contractor’s premises.




Pumps, fans, compressors and apparatus shall be tested at the

manufacturer’s works. If two or more identical pumps, fans,

compressors and apparatus etc. are supplied a complete

performance test is to be carried out on the first unit only. Such

performance test shall comprise the verification of the discharge

capacity against discharge pressure, power input and efficiency

and other performance data requested in the specification. The

respective test diagrams shall be provided. Subsequent units

need to be tested only if test results obtained from the first unit

prove doubtful or unsatisfactory.

Evidence and diagrams of previous ‘type tests’ undertaken on

identical design of pumps, fans, compressors and apparatus may

be acceptable instead of further complete performance tests, but

the purchaser’s and or consultant’s approval must be sought in

each case. A test at the duty point will, however, in any event be

required. Particular requirements have also been set out in the

specifications.

As far as possible tests on pumps in the manufacturers works

shall be carried out with suction conditions as those after

installation at the site.

Cubicles, cabinets and control boards shall, prior to their

inspection and testing, be completely definitely assembled,

equipped and wired internally in the supplier’s or his sub

contractor’s shops.

Shop testing shall include functional tests as the case may be part

or complete assemblies to the extent practicable and agreed. Such

tests shall be performed under, as far as possible in operation like

conditions.

When requested by the purchaser the functional tests shall be

repeated or extended until proof has been obtained that the




functioning of the assemblies will comply with the requirements

of the specification.

2.18.4 TESTS AT SITE

During erection and installation work at site, the equipment shall

be subject to tests which may include but not be limited to the

testing, checking, inspection and examination of all equipment

assembled/welded and set up at the site. The procedure may be

confirmed up to final acceptance of the works.

The supplier shall provide at his cost, all competent personnel

(including those from sub-supplier) as well as all equipment,

material and other services required for the proper and thecomplete testing and putting into commercial service of all

equipment. If in the opinion of the Purchaser not sufficient

competent personnel have been delegated, the Purchaser may

request the Supplier to send additional appropriate competent

personnel to the site.

Further to the tests, checks, examinations etc, stipulated in

technical specifications, the tests at the site shall comprise but notbe limited to:

- Checks and examination of welds

- Hydrostatic pressure tests

- Tightness tests

- Dielectric tests

- Dry rotation tests (with clearance and run out checks)

- Functional checks (on protective devices, automatic and

manual controls, monitoring, supervisory equipment etc.)

- Running tests

- Reliability tests

- Performance tests and determination of characteristic data

and tests in particulars of the turbine and generator.




- Turbine acceptance tests (in accordance with IEC-

Publication for “field acceptance tests to determine the

hydraulic performance of hydraulic turbines”)

- Regulator acceptance tests (in accordance with the IEC

Publication 308, 1970, “International Code for testing of

speed governing systems for hydraulic turbine”)

Stability tests of the unit when running in parallel with all such

tests and checks shall be performed in the presence of the

Purchaser and/or his Consultant. If not satisfied with the

performance or outcome of the tests and checks he shall have the

liberty to ask for additional tests or repetition of the same.

2.18.5 RELIABILITY TESTS

After the supplier has notified the purchaser and received his

agreement that the equipment is ready for commercial services,

the generating units may be operated continuously at rated speed

and maximum output for a maximum period compatible with site

conditions.

After successful completion of such tests, the unit shall beoperated under the various conditions envisaged within the limits

of maximum output either continuously or intermittently,

including mode changing operation for a period of ninety (90)

days with a view of obtaining useful information and to verify if

the interest of specifications are met or otherwise.

The purchaser’s staff will operate the equipment with the

assistance and as per the advice of the supplier’s staff during the

reliability test period. The supplier may request any minor

adjustments, which may be necessary provided that such

adjustments do not in any way, interfere with or prevent the use

of the equipment by the purchaser or result in reducing the output

or decreasing the efficiency.




If any failure or interruption occurs in any portion of the

equipment covered by the contract due to, or arising from faulty

design or materials, or workmanship (including construction at

site) sufficient to prevent full use of the equipment, all the

reliability tests shall be repeated after the supplier has remedied

the cause of failure or interruption.

2.19 APPLICABLE STANDARDS

Unless otherwise specifically stated, the applicable standards would be

the latest revisions of the relevant IEC standards/codes or other

standards, which are equivalent to IEC. In case the material and

equipment is manufactured in India, relevant Indian Standard, if available shall be applicable. The supplier is requested to get himself

acquainted with Indian Electricity Acts and Rules and follow those.

Generally applicable standards are as under but not limited to:

IEC standard for main pump turbine

IEC 193(1963) International code for model acceptance tests of

hydraulic turbines (code X) Amendment No.1

(1977) (code K)IEC 193A (1972) First supplement (code P)

IEC 308(1970) International code for testing of speed governing

system to hydraulic turbine (code X)

IEC 497(1976) International code for model acceptance tests of

storage pumps (code X B)

IEC 41(1991) Field acceptance test to determine the hydraulic

performance of hydraulic turbine storage pumps

and pump-turbines.(code XK)

IEC 545(1976) Guide for commissioning, operation and

maintenance of hydraulic turbines (Code S)

IEC 609(1978) Cavitations pitting & valuation in hydraulic

turbines, storage pumps & pump turbines (Code P)




IEC 994(1991) Guide for field measurement of vibration and

pulsation in hydraulic machines (turbine, storage

pumps and pump-turbines) (Code XB)

IEC 995(1991) Determination of prototype performance from

model acceptance tests of hydraulic machines with

consideration of scale effects. (Code V)

Note: IEC 198(1966) acceptance tests of pump turbines and IEC 609

(1978) Thermodynamic measurement are replaces to IEC 41 (1991)

IEC standard for accessories of pump turbine.

IEC 298(1990) A.C. metal enclosed switchgear and control gear for

rated voltage above 1 KV and up to and including

52 kV (code XA) Amendment No.1 (1994) (Code

K)

IEC 264 Packaging of winding wires 264.1, 264.2, 264.2.1,

264.2.2, 264.2.3, 264.3, 264.3.1, 264.3.2, 264.3.3,

264.3.4, 264.4, 264.4.1, 264.4.2.

IEC 502(1994) Extruded solid dielectric insulated power cables for

rated voltage from 1 kV up to 30 kV (code XA)

IEC 227 Polyvinyl chloride insulated cables of rated voltage

up to and including 450/750 V, 227.1(1993) (code

S), 227.2(1979)(code K), 227.3(1993) (code Q),

227.4(1992) (code H)-227.5(1979) (code P),

Amendment No.1 (1987) (code B), Amendment

No.2 (1994) (code D), 227-6(1985) (code L).

IEC 228(1978) Conductors of insulated cables (code M)

Amendment No. 1(1993) (code D)

IEC 228 A (1992) First supplement, Guide to the dimensional limits

of circular conductors (code E)




IEC 287(1982) Calculations of the continuous current rating of

cables (100% load factor) (code XB)

Amendment No. 1 (1988) (code G)

Amendment No.2 (1991) (code E)

Amendment No 3(1993) (code L)

IEC 287.1.2(1993) Part 1: Correct rating equations (100% load factor)

and calculations of losses - Section 2 Sheath eddy

current loss factor for two circuit in flat formation.

(Code U)

IEC 287.2-1(1994) Part 2: Thermal resistance section 1: and

calculation of thermal resistance.(Code V)

IEC 947-2(1989) Part 2: Circuit breaker (This publication SupersedsIEC 157-1 (Code XB)

Amendment No.1 (1992) (code U)

Amendment No.2 (1993) (code S)

IEC 947-4-1(1990) Part 4 contactors and motor starters Section 1

Electro mechanical contractors and motor - starter

(code XD) (This publication supersets IEC 158-

1(1970) and its Amendment (1983) and 158-1c.IEC 269 Low voltage fuses

269-1 (1966) Part 1 General requirements (code XB)

Amendments No.1 (1994) (code B)

269-2(1986) Part 2 Supplementary requirements for fuses for use

by authorized persons (fuses mainly for industrial

application) (code G)

269.2.1. (1987) Part2 Supplementary requirements for fuses for use

by authorised persons (code D)

Amendment No. 1 (1993) (code F)

Amendment No.2 (1994) (code B)

269-3 Part 3 Supplementary requirements for fuses for

uses by unskilled persons (code L)




34-1, 34-2A, 34-3, 34-4, 34-5, 34-6, 34-7, 34-8, 34-

9, 34-10, 34-11, 34-11-2, 34-11-3, 34-12, 34-13,

14-14, 14-15, 34-16-1, 34-16-2, 34-17, 34-18-1, 34-

18-2, 34-183.

IEC – 76 Power transformers 76-1 (1993) - 76-2 (1993), 76-3

(1980), 76-3-1 (1987), 76-5 (1976).

IEC 56(1987) High voltage alternating current circuit breakers

(code XH) Amendments No.1 (1992) (Code

M)831, 871




SECTION - III

SCHEDULE OF REQUIREMENT

A) MECHANICAL LOT

B) ELECTRICAL LOT




SECTION III

SCHEDULE OF REQUIREMENT

INDEX

Sr. No. Description Page No.

MECHANICAL LOT

3.1. Turbine 63

3.2 Butterfly Valve 65

3.3 Station Auxiliaries 66

3.4 Spares. . 67

ELECTRICAL LOT

3.5. Generator and Static Excitation 69

Equipment

3.4 Spares. . 72




SECTION-III

SCHEDULE OF REQUIREMENTS

A MECHANICAL LOT

3.1 TURBINE

1 No. Vertical shaft Francis turbine.

Turbine shall consist of

1 No. Intake pipe of suitable length between main inlet valve and

spiral case.

1 Set. Expansion joint, air release valve and thrust collar

complete.

1 Set Penstock pipe piece between penstock and BFV of

required length with stiffeners, installation material, pipes,

valve etc. complete. Valve shall be suitable for operation

from inlet valve floor.

1 Set Guide Vanes, greaseless bearings (self-lubricated type),

regulating apparatus, servomotor double acting type etc.

complete with locking device, oil pipelines, valves,

pressure gauges, limit switches etc.

One Stay ring and spiral case.

One Runner in one piece or divided in minimum parts

One Head cover and upper wicket gate ring in one piece or

divided in minimum parts.

One Bottom ring, lower wicket gate ring and runner chamber in

one piece or divided in minimum parts.

One Elbow type Draft tube liner. Draft tube steel liner shall

extend up to the point where it is connected to tailrace.

The liner shall be complete with drain valve, drain piping,

manhole with door, pressure gauges, manometers, probes,

anchors, turn buckles etc.

One Shaft




One Shaft seal with cooling water system complete including

pressure reducers, strainers, filters and plant to provide

clean water.

One Guide bearing with pads, oil coolers, Resistance

temperature detector (R.T.D.’s), Dial type thermometers

(D.T.T.’s) etc. with piping , valves etc.

One Pit liner provided with ribs, anchor hooks etc.

Lot Thermometers, thermal relays, all level gauges and relays,

water pressure gauges and relays etc. Gauges, temperature

indicators etc. for mounting on Gauge Panel.

1 Set Oil leakage system if needed (requirement shall be

justified at bidding stage) complete with tank, motor-pumpsets, pipes, valves, level switches, gauges etc.

1 Set Water level measuring devices.

1 Set mechanical over speed device

Lot Control and Power Cables :- Power cables for local

control centres to equipments, local control centres to unit

control boards and up to distribution centres provided by

Purchaser, shall be provided by the Supplier. Power cablesbetween two equipments which are in the scope of this

contract shall be supplied by the Supplier. All control

cables, racks, cleating, ferrule, glands etc. for entire

system of equipment covered under the scope of supply of

the supplier shall also be provided by the supplier. All

cables shall be of FRLS copper conductor.

Lot Oil, grease, lubricants sufficient for first filling and 25%

spare quantities.

Lot All accessories viz. sole plates, foundation and anchor

bolts, platforms, ladders, guards, hand rail, bolts, nuts, turn

buckles etc. complete including requirement during

installation and of permanent nature.




1 Set Turbine junction box.

1 Set Runner inspection & maintenance platform suitable for

fixing in the draft tube.

1 Set Necessary instrumentation, control, safety devices etc.

along with the spares and special tools and plants required

for erection, operation & maintenance including the

following.

- Runner removal tools complete.

- Hydraulic jacks for pre-stressing of the shaft

coupling bolts.

- Hydraulic jacks for pre-stressing of the head cover

and bottom ring.- Tools and Tackles required for handling of guide

and thrust bearing.

- All tools for assembling and dismantling guide

bearing, shaft seal, bottom ring, runner, guide vane,

guide vane link, turbine shaft support collar etc.

- Test equipment required for hydraulic pressure test

of spiral case and stay ring.1 Set All test kits, instruments, meters etc. for commissioning,

routine and special tests at site.

1 Set Slings for handling the bearing, runner, shaft head cover,

servomotor etc.

GOVERNOR

1 No. Turbine regulator of digital type.

3.2 MAIN INLET VALVE (MIV)

1 No. Butterfly valve about 2000 mm internal diameter provided

with service and maintenance seals complete with oil

hydraulic drive, main and stand-by pump-motor unit for




servomotor closing/opening operations complete with air

valve, by pass valve, draining system all accessories

gauge, meter, indicators etc. complete.

1 Set Erection and maintenance tools for butterfly valve.

3.3 STATION AUXILIARIES

3.3.1 COMPRESSED AIR SYSTEM

Compressed air system for generator mechanical brakes and general

requirements comprising of adequate No. of power plant compressors,

pressure receivers, pressure switches, pressure gauges, temperature

detectors, pipe lines, valves, control panels etc shall be provided.

3.3.2 COOLING WATER SUPPLY SYSTEM

Cooling water system required for of unit is tapped from penstock

before butterfly valve and the water after circulation shall be discharge

in to Tail race.

Cooling water supply system shall include following

* Booster pump-motor units.* Control Switchgear.

* Valves strainer duplex filters and piping with control devices,

instruments etc. complete.

* The piping shall be complete from tap from penstock up to

discharge point.

3.3.3 DRAINAGE SYSTEM & DEWATERING SYSTEM

Comprising of adequate no. of submersible type, pump-motor units,

complete with control, protection and switch gear panels, level control

devices, piping, valves, check valves, clamps, supports, anchors etc.

The piping shall be complete from pump room up to discharge point.




3.4 SPARES

A) TURBINE

1/4 Set Guide Vanes.

1 Set Guide vane stem bearing.

1 Set Guide vane stem seal.

1 Set Guide bearing segments.

1 Set Piston rings for servomotor.

1 Set Shear pins for guide vane mechanism

1 set Necessary spares for shaft seal

1 Set Shaft seal water filter elements

1piece Removable protective bush of shaft

1 Set Solenoid coils per solenoid used.1 Set Flow relay of each type used.

1 Set Annunciator lamps of each type used.

1 Set Mercury thermometer of each type used.

1 Set Resistance thermometer of each type used.

1 Set Limit switch of each type used.

1 set Friction elements for guide vanes

Lot Necessary recording charts for one year operation.1 Set Consumables such as all packing, gasket and jointing

material used throughout the turbine assembly , including

those for the servomotors and for man doors.

1 Set Ten per cent(10%) of all bolts, screws, nuts and washers

used up to and including M30 size.

B) FOR GOVERNOR AND OIL PRESSURE SYSTEM

1 Set Oil Pump complete with motor.

1 set Hydraulic amplifier .

1 Set Pilot and control valve complete.

1 Set Transducers.

1 Set Equipment for changing turbine speed




1 Set Equipment for limiting the opening of Guide vanes.

1 set Oil pump for pumping leakage oil.

1 Set Printed circuit boards used for speed and guide vanes limit

setting.

1 set Safety relief valve

1 Set Setting potentiometer of each type used.

1 Set Float switches, pressure, flow and temperature relays of

each type used.

1 Set Solenoids for each type of solenoid valve used.

1 Set Fuses of each type used.

1 Set Each kind of filter used.

1 Set Complete set of all packing, gasket and jointing materialused.

1 Set Ten percent(10%) of all bolts, screws, nuts and washers up

to and including M 30.

C) FOR BUTEERFLY VALVES.

1 Set Service seal with all fixing.

1 Set Maintenance seal with all fixing1 Set Servomotor piston rings and packings

1 Set Instrument and indicator of each type used.

1 Sets Control solenoid of each type used.

1 Set Flow relay and manostat of each type used.

1 Set Limit switch of each type used.

1 Set Valve of each type used.

1 Set Necessary recording charts for one year operation.

1 Set Complete set of all packing, gasket and jointing material

used throughout the regulator equipment.

1 Set Ten percent (10%) of all bolts, screws, nuts and washers

up to and including M 30.




D) FOR STATION AUXILIARIES DRAINAGE

AND DEWATERING EQUIPMENT

Completely assembled submersible

pump-motor set 1 No.

CONTROL AND SAFETY DEVICES

i) Limit Switches 1 Set

ii)Level Switches 1 Set

iii)Float Switches 1 Set

iv)Pressure Switch 1 Set

v)Flow Relays 1 Set

COMPRESSED AIR SYSTEM

i) Piston Rings 1 Set

ii)Unloader valves 1 Set

iii) Bolts 1 Set

iv) Gasket 1 Set

v) Oil filter elements 1 Set

vi)All types of valves 1 Set

B ELECTRICAL LOT

3.5 GENERATOR AND STATIC EXCITATION EQUIPMENTS.

Two Nos. Vertical shaft generator suitable for direct coupling with

Vertical shaft Francis turbine.

Generator shall comprise of:

One No. Closed circuit ventilation system air-cooled type

One No. Stator assembly complete with frame, core and winding.

One No. Rotor assembly complete with spider rim, brake, jacks,

field winding etc.




One No. Shaft with coupling flanges and bolts etc. complete.

One No. Bottom bracket with lower guide bearing, complete with

supporting structure oil reservoir etc.

One No. Top bracket with combined thrust and upper guide bearing

complete with oil reservoir and supporting structure etc.

One No. Forced lubrication system for combined thrust and guide

bearing with externally mounted oil coolers complete with

all the oil and water piping with valves, flow relays.

One Set. High-pressure injection lubrication system for lubrication

of thrust bearing during starting and stopping of the unit.

One Set Air coolers (Air/Water heat exchangers) with valves,

connecting piping, flow meter, thermometers and otherfittings for generator cooling.

One Set. Sole plates, foundation bolts, dowels and other fittings

required for proper erection, levelling and alignment of

stator and bottom bracket and top bracket.

One Set. Air guide cum air seal assembly.

One Set. Brake and jack cylinders complete with all the necessary

internal and external pipe work, valves, electrical remoteswitches with contacts and with brake dust collector.

One No. Speed signal sensing device.Signal sensing device shall be

complete with casing suitable to cover over speed device

also.

One Set. Brush gear system with slip rings and brushes.

One Set Static excitation system complete with excitation

transformer, thyristor cubicles, field flashing system,battery field flashing provision, field suppression cubicle

with field breaker and discharge resistor, etc. complete.

One No. Digital voltage regulator.

One Set. All instruments and devices such as dial type

thermometers, pressure gauges, resistance temperature




detectors, thermostats, flow relays, oil level switches etc.

complete shall be provided.

One Set. Turbine, generator gauge panel containing temperature

gauge both of turbine and generator.

One Set. Temperature scanners to be mounted on unit control board

for monitoring temperature of thrust and guide bearings,

stator and field windings, cold and hot air temperature of

generator cooling air with 3 sets of contracts. Each set

consisting of two potential free normal/open contacts

operating at two different levels of temperatures to be used

for external annunciation scheme. The scanner shall be

suitable to operate on the inputs from RTD (Resistance

Temperature Detectors).

One Lot Local control boards for equipment wherever necessary

for control indication and alarm of the system shall be

provided.

One Set Rotor lifting device if required.

One Set Complete erection tools required.

One Lot Testing equipment comprising the following

I) 5kV megger, mains operated. 1No.

II) 10kV megger, mains operated. 1No.

III) Lubricating oil filter (Centrifugal type) 1No.

IV) 10kV, tan-delta measuring kit 1No.

One lot Mulsifire system

One Set: Operation and maintenance tools

One Set Current transformers on Neutral side of generator.

One Set Current transformers in tap-off for excitation transformer.

One Set Shorting Links for dry out and short circuit test

In =1000 A.

One Set All special tools required for erection and maintenance.




One Set 12Nos. Single Phase Current transformers for Generator

protection

One set LAVT cubical with PTs, Lighting arrestor, Surge

capacitor, isolator cubicle

One Set Generator neutral

One set Neutral grounding cubicle with grounding transformer,

resistor and voltage transformer.

Lot Connectors, support structure hardware etc.

Lot Fittings, accessories.

One Set Special tools required for erection and maintenance.

One Set Microprocessor based supervisory control and Data

acquisition system

One Set Microprocessor based protection relays ( Main and Back-

up)

SPARES

1. GENERATOR1 Set Stator upper and lower bar with insulating material to form

1/3 stator winding.

2 Nos. Rotor field coils complete with insulation

1 Set Generator Guide bearing segment/pads

2 Nos. Brake assembly with shoes.

1 Set Brushes with Brush holders.

1 Set Brake liner

1 /2 set Generator air coolers

1 Set Oil coolers for combined bearing.

1 Set Dial type Thermometer

1 No Over speed device.




1 Set Thermostat for air circuit and bearing etc.

1 Set water flow relays for air coolers ,bearing etc.

1 Set Gaskets for brake cylinders

1 Set Gaskets . washers for air water coolers.

1 Set Speed device equipment.

½ Set Fans with driving electrical motors.

1 No Embedded detector for bearings.

2. EXCITATION AND DIGITAL VOLTAGE REGULATOR

EQUIPMENT

Parts of magnetic contactor1 Set Contactor

1 Set Operating coils

1 Set Printed circuit board for DVR(modules).

1 Set Uninterrupted Power supply in DVR

1 Set Converting measuring and supervision units for slips

stabilization

1 Set Rotor angle limiter1 Set Rotor Current limiter

1 Set Stator Current limiter

1 Set Pulse Comparison units

1 Set Digital Voltage Adjuster

1 Set Digital potentiometer

1 Set Feed back module

1 Set Grid control unit

1 Set Pulse Amplifier

1 Set Pulse Supervision unit

1 Set Voltage supervision unit

1No Over – current relay for excitation transformer

1 No Rotor earth fault relay




1 No Network filter

3 Nos Thyristor element and fuse

1 No Thyristor ridge

1 No Field breaker

1 Set De-excitation discharge resistor

1 Set ripping coil

1 Set Closing Coil

1 No Field flashing rectifier

3Nos Blocking diodes for field

2Nos Ventilation fans

1 Set Grid control unit

1 Set Pulse Amplifier1 Set Pulse Supervision unit

1 Set Voltage supervision unit

1No Over – current relay for excitation transformer

1 No Rotor earth fault relay

1 No Network filter

3 Nos Thyristor element and fuse

1 No Thyristor ridge1 No Field breaker

1 Set De-excitation discharge resistor

1 Set Tripping coil

1 Set Closing Coil

1 No Field flashing rectifier

3Nos Blocking diodes for field

2Nos Ventilation fans

3 Supervisory Control and Data Acquisition System

1 Lot Copy of software

1 Set Interfacing cable each type

1 Set Report printing papers

1 Set Spares of computer




1 Set Spares of printer

4. Protective Gear

1 Lot Copy of software

1 No. I/P module each type

1 No. O/P Relay module

1 No. Power supply module

1 Set Connecting cables

5 Panels

1 Set Indicating lamp each type used

1 Set Push button/ selector switches

1 Set Auxiliary relays

1 Set Meters each type used1 Set Fuse carrier and base

1 Set Fault, operation and symbol indicator assembly.

Five of Lens for symbols

Each kind.

1 Set Indicating LED & Lamp

1 Set Fuse of each size used

One of Transducer

Each kind

10% of Wrapping label and marketing strip

installed

Quantity

One pair Plug-in type connection accessories

Of each kind




6 LAVT AND NG CUBICLE

1 No. PT

11kv/ 110v/ 110v

J3 J3 J3

Core-1, 100VA, CL. 0.2

Core-2, 200 VA, CL 3P.

1 No. LA

1 No. Surge capacitor

7 CURRENT TRANSFORMER ( CT)

1 Set CTs single phase as used in Generator Protection Circuit1 Set CTs single phase as used in Generator neutral circuit




SECTION - IV

MATERIAL OF MAJOR COMPONENT




SECTION NO. IV

MATERIAL OF MAJOR COMPONENT INDEX

Sr. No. Description PageNo.

1. Material of major component 79




SECTION - IV

MATERIAL OF MAJOR COMPONENTS

The description of materials and the tables attached to this section shallbe deemed to form part of these specifications. The bidder shall note therequirements and shall state in his bid that the requirements are fullycomplied or otherwise. In any case, he must supply the informationabout the materials to be used in the construction of the plant andequipment in a tabular form.




KAL Hydro Electric Project ( 1X15 MW)

Material List of the turbine and its Auxiliary Equipment

No Name of parts

Type of material

Main materialIS or equiv.

Chemical composition of material Mechanical properties of the mate

C(%) P(%) S(%) Other

elements

contents

Ultimate

tensile

strength Us

Mpa

Yield

strength

Ys Mpa

Normal design

stress

(primary)

Mpa

Normal

safety

factor

A

de

(

1 Runner casting SCS6 0.06 0..40 0.030 750 550 150 1/5 Us

2 Turbine shaft forging SF540A 0.60 0.030 0.035 540 ~ 640 275 68.75 1/4 Ys

3 Head cover plates SM400B 0.22 0.035 0.035 400 ~510 215 100 1/4 Us

4 Stay ring plates SM490B 0.20 0.035 0.035 490~610 295 122.5 1/4 Us

5 Spiral case plates SM570 0.18 0.035 0.035 570~720 420 142.5 1/4 Us

6 Guide Vane casting SCS5 0.06 0.040 0.040 740 540 148 1/5 Us

7 Guide vane

stem

casting SCS5 0.06 0.040 0.040 740 540 148 1/5 Us

8 Wearing

plate

Plates SUS410 0.15 0.040 0.030 440 205 / /

9 Stationarywearing ring

castingplates

SCS1SUS410

0.150.15

0.0400.040

0.0400.030

540440

345205

/ /

/ /

10 Guide vane

operatingring

Plates SS400 / 0.050 0.050 400~510 215 107.5 1/2 Ys

11 Bottom ring Plates SM400B 0.22 0.035 0.035 400~510 215 100 1/4 Us

12 Draft tubeliner

Plates SS400 / 0.050 0.050 400~510 215 107.5 1/2 Ys

13 Guide vane

Servomotor

piston

casting FC250 / / / 250 / 50 1/5 Us

14 Guide vane

servomotor

cylinder

Plates SS400 / 0.050 0.050 400~510 215 100 1/4 Us

15 Turbine pitliner

Plates SS400 / 0.050 0.050 400~510 215 100 1/4 Us

16 Connecting

bolt betweenmain shaft

and runner/

Chromium

molybdenumsteel

SCM435 0.33~

0.38

0.030 0.030 930 785 523.3 2/3 Ys

17 Sealing plate

for main

shaft seal

Plates SS400

Stainless Steel

overlay

/ 0.050 0.050 400~510 215 / /

18 Inlet valveextension

pipes

Plates SM570 0.18 0.035 0.035 570~720 420 142.5 1/4 Us

19 Oil sump

tank

Plates SS400 / 0.050 0.050 400~510 215 107.5 1/2 Ys




No Name of

parts

Type of

material

Main material

IS or equiv.

Chemical composition of material Mechanical properties of the mate

C(%) P(%) S(%) Otherelements

contents

Ultimatetensile

strength Us

Mpa

Yieldstrength

Ys Mpa

Normal designstress

(primary)

Mpa

Normalsafety

factor

Ade

(

20 Pressure oil

tank

Plates SB480 0.33 0.035 0.040 480~620 265 120 1/4 Us

21 Air receiver Plates SPV410 0.18 0.030 0.030 550~670 410 137.5 1/4 Us

22 Valve bodyfor main

distributing

valve of

governor

casting SC450 0.35 0.040 0.040 450 225 90 1/5 Us

23 Piston for

maindistributing

valve of governor

forging SF540A 0.60 0.030 0.035 540~690 295 196.6 2/3 Ys

24 Butterflyvalve body

Plates SM400B 0.22 0.035 0.035 400~510 215 100 1/4 Us

25 Butterflyvalve rotor Plates SM400B 0.22 0.035 0.035 400~510 215 100 1/4 Us

26 Butterfly

valve

extensionpipes

Plates SM400B 0.22 0.035 0.035 400~510 215 100 1/4 Us

27 Butterfly

valve shaft

forging SF490A

stainless steeloverlay

0.60 0..030 0.035 490~590 245 122.5 1/4 Us

28 Governor

pressure oil

pipes

Carbon steel

pipe

STPG370 0.25 0.040 0.040 370 215 92.5 1/4 Us

29 Oil pressuresystem pipes

Carbon steelpipe

STPG370 0.25 0.040 0.040 370 215 92.5 1/4 Us




MATERIAL LIST OF THE GENERATOR AND ITS AUXILIARY EQUIPME

Chemical composition of materials Mechanical properties of the materials an

No. Name of

parts

Type of

material

Main material

IS or equiv

C(%) P(%) S(%) Other

elements

contents

Ultimate

tensile

strength

Us Mpa

Yield

strength

Ys Mpa

Normal design

stress(Primary)

Mpa

Normal

safety

factor

Abnorm

design

stress

(Primar

1 Stator

Frame

Plates SS400 - 0.050 0.050 400 ~ 510 215 100.0 1/4 Us 143.3

2 Stator

Core

Silicon

Steel

C2552 - - - - - - - -

3 Stator

Coil

Copper C3 104 No.3-4 - - - - - - - -

4 Field

Coil

Copper C3 104 No.2 - - - - - - - -

5 Main

Shaft

forging SF540A 0.60 0.030 0.035 540 ~ 640 275 68.8 1/4 Ys 183.3

6 Pole

Core

plates PCYH300 - - - 400 300 100.0 1/4 Us 200.0

7 Rotor

Rim

Massive

plates

SM570 0.18 0.035 0.035 570 ~ 720 450 142.5 1/4 Us 300.0

Laminate

plates

PCYH600 - - - - 700 600 175.0 1/4 Us 400.0

8 Thrust

Runner

forging SF590A 0.60 0.030 0.035 590 ~ 690 295 147.5 1/4 Us 196.7

9 Thrust

Block

forging SF540A 0.60 0.030 0.035 540 ~ 640 275 135.0 1/4 Us 183.3

10 Base-

metal

Bearing

plates SS400

- 0.050 0.050 400 ~ 510 215 100.0 1/4 Us 143.3

11 Bearing

metal

white

metal

WJ2 - - - - - - - -

12 Upper &

Lower

Bracket

plates SS400 - 0.050 0.050 400 ~ 510 215 100.0 1/4 Us 143.3

13 Miscella

neous

Cover

plates SS400 - 0.050 0.050 400 ~ 510 215 107.5 1/2 Ys 143.3

14 Sole

Plate

plates SS400 - 0.050 0.050 400 ~ 510 215 107.5 1/2 Ys 143.3

NOTE : Composit ion of materia l shal l be as per IS/ASTM




SECTION – V

TECHNICAL SPECIFICATIONS OF TURBINE




SECTION NO. V

TECHNICAL SPECIFICATION OF TURBINE

I N D E X

CLAUSE NO. Description PAGE

NO.

5.1.

5.2.

5.3.

5.4.

5.5

5.6

5.7

5.8

5.9

5.105.11

5.12

General

Type and rating

Guarantees vis-a-vis liquidated damages

Field test and acceptance test

Detailed Construction specifications of

component turbine.

Governing System

Electrical Equipment

Drawings and Manuals to be furnished

after award of contract.

Assembly and inspection at factory

Test Certificate and inspection reportsTests on site

Standards

ANNEXURES

Annexure V-1 to V-5

DATA SHEETS

85

85

86

89

90

112

123

126

127

127129

129

131

148



Signature of Bidder Signature of Purchaser 85

SECTION – V

TECHNICAL SPECIFICATIONS OF TURBINE

5.1 GENERAL

5.1.1 This section covers technical specification and requirements of Turbine

and associated auxiliaries.

5.1.2 The turbine and generator unit shall match in respect of speed, over-

pressure, over-speed and runaway speed, moment of inertia, outputs,

coupling and other requirements.

5.1.3 For operational and design requirements, relevant provisions of section Ishall be applicable.

5.2 TYPE AND RATING:

1) Number of units : 1 No.

2) Type : Vertical shaft single stage Francis type

turbine in a steel spiral case and suitable for

direct coupling with the generator.

3) The hydraulic data and the other data regarding water conveyance

system is as follows:

B) LEVELS :

a) Minimum Draw Down level 140.50 m

b) Full Reservoir water level 170.00 m

c) Maximum tail water level 35.00 m

d) Minimum tail water level 32.00 m




B) OPERATION HEADS

1. Maximum net head 117.00 m

2. Minimum net head 84.00 m

3. Rated net head 106.00 m

4) Head variation 79.24 to 110.37%

5) Design Discharge 17.69 m3 /s

The turbine shall be designed based on the hydraulic data mentioned

above.

5.3 GUARANTEES VIS-À-VIS LIQUIDATED DAMAGES:-

GENERAL:The supplier shall guarantee that the turbine in its entirety, including all

related equipment, material and structure furnished under this

specification will be free from defects in design, material and

workmanship. The Supplier shall warrant the successful operation of all

such equipment.

(i) EFFICIENCY GUARANTEE: - The weighted average efficiency of full

size turbine under rated net head of 106 m at rated speed shall beguaranteed as per formula given below.

Eav=1/3 (E100+E75+E50)

Where Eav = weighted average efficiency.

E100, E75, E50 are the efficiencies respectively at 100%, 75%, 50% of

rated turbine output. For Efficiency Guarantee, Bidder shall give values

of efficiencies at 100%,75% and 50% of rated turbine output in data

sheets and also in Annexure V-5 of this section.

The above guarantee shall be based either on field tests or on model tests

as per IEC test codes. If field test is opted, this shall be performed within

90 days of commissioning of turbine. For this purpose the provisions of

inspection and field repair of the machine before the test would be




applicable. The penalty on account of shortfall in efficiency is given in

Volume-I.

(ii) OUTPUT GURANTEE: - The supplier shall give guarantee in respect of

values of turbine output at rated net head of 106 m , maximum net head

of 117m and minimum net head of 84.0m. The supplier shall also give

guarantee for the maximum output (110%) from turbine. Penalty for

any short fall in output is given in Volume-I.

(iii) CAVITATION GUARANTEE: - The turbine runner shall be

guaranteed against excessive pitting due to cavitation for a period of

4000 Hrs of actual operation within a period of 24 months from the dateof commissioning but before expire of warranty period. The supplier

shall however, be entitled to make sure within six months after

commissioning that cavitation damage is not caused or aggravated by

local defects of turbine shape as well as to repair the damage that may

have been caused and take steps to prevent future cavitation damage.

Existence of excessive pitting is defined as the rate of metal removal

from the runner due to cavitation more than the rate given by formula.W=0.1 D² kg per 1000 hrs of operation.

Where W = loss of weight of metal due to cavitations in kg.

P = Runner discharge diameter in meter.

The guarantee does not cover the removal of metal by erosion,

corrosion, the presence of injurious foreign elements in the water, or the

removal of metal by chipping and grinding preparatory to repairing the

pitted area. The cavitations damage shall be evaluated by the sum of all

separate masses. The mass for each part damage shall be calculated as

half the product of its maximum depth, the area with a depth exceeding

0.5 mm and the density of the material.




Should the runner show excessive pitting within the guarantee period

specified above, Supplier undertakes to repair the runner by welding,

chipping and grinding.

Cavititation damage is of spongy nature. The damage by erosion and

corrosion is distinct from cavitation and can be identified by visual

inspection.

(iv) MAXIMUM MOMENTARY OVERSPEED:

The supplier shall guarantee that the maximum momentary over speed

under most unfavourable transient conditions according to IEC

41(1991), sub-clause 2.3.4.14 will not exceed 1.50 times the rated

operating speed.

(v) MAXIMUM STEADY STATE RUNAWAY SPEED:

The Supplier shall guarantee that the maximum steady state runaway

speed according to IEC 41(1991), sub-clause 2.3.4.15 will not exceed

1.70 times rated speed.

(vi) MAXIMUM/MINIMUM MOMENTARY PRESSURE:The supplier shall guarantee that the maximum and the minimum

momentary pressure under most unfavourable transient conditions

according to IEC 41(1991), sub-clause 2.3.5.7 shall not exceed

guaranteed values of data sheets.

(vii) VIBRATION AMPLITUDE:

The amplitude (zero to peak) of vibration according to Rathbone chart

shall be less than 75 µm (microns).

Should for any reason the above limit exceed, the supplier shall take at

his own cost, all steps to remedy the situation and to reduce the vibration

to the above stated limits.




(viii) NOISE LEVEL:

When units are in operation at most unfavourable conditions in any

mode, noise level measured in the turbine pit shall not exceed 90 dB(A).

Further, the maximum noise level, on the turbine and generator floor

levels at a point outside barrel shall not exceed 90 dB(A).

(ix) RESONANCE:

The supplier shall guarantee that turbine is capable of operating

continuously and smoothly without hunting in the entire operating

range.

The supplier shall confirm that the turbine design is such that the power

pulsation at generator terminal is within ±1.5% at full load and ± 5% atpartial load of actual rated output.

5.4 FIELD TESTS AND ACCEPTANCE TESTS

Only the tests regarding vibration, noise, temperature-rise, stable

operation, over speed and over pressure shall be conducted to verify the

guaranteed performances. The performance guarantees i.e. output and

efficiency figures for turbine equipment being supplied under thiscontract shall be on the basis of report of turbine model test already

carried out by the supplier for similar profile. The Supplier shall submit

the test reports along with calculations to prove the efficiency and output

of the turbine. If the calculations are agreeable to the purchaser the

model test will not be insisted and the turbine on the basis of data

furnish by the contractor will be accepted. If the model test reports of

similar profile is not available with the Supplier then model test shall be

carried out by supplier without extra cost to Purchaser. To ascertain

guaranteed performance values, the model test result form basis of

acceptance. The guarantee at the discretion of Purchaser shall be subject

to verification by field test. Charges for field test shall be shown

separately in price schedule. If the field tests are decided to be done for




final acceptance, for arriving at the liquidated damages for non-

conformity with guaranteed values, field tests will prevail, if the results

obtained during field tests differ from those guaranteed by the Supplier,

he shall pay the liquidated damages as per the provisions stipulated in

Volume-I.

Irrespective of whether the field efficiency & output test is conducted or

otherwise the supplier shall have to prove at site the guarantees of

energy generated and water released during turbine mode in one-week

operation cycle. The supplier will have to establish and prove the

relation of;

* Energy generated during operation cycle of one week.

No bonus will be given to supplier in case of better resultshowever Purchaser reserve the rights to reject the equipment in

case of failure to meet the guaranteed values with variation limit

specified in Annexure III-2 of Volume-I.

5.5 DETAILED CONSTRUCTION SPECIFICATIONS OF

COMPONENTS OF TURBINE

5.5.1 STAY RING AND SPIRAL CASE ASSEMBLY

i) CONSTRUCTION:

Stay ring and spiral cases shall be of welded construction. High

tensile, high strength steel plates confirming to material list

attached with Section IV shall be used. Intake pipe of suitable

length to connect Butterfly valve with spiral case shall also be of

similar material. The assembly shall be designed to account for

fatigue stresses induced due to increasing operational duties for

example frequent starting, stopping, and abnormal conditions.

Steel plate, which is used in the construction, shall be free from

defects such as harmful seams, laminations, blisters, snakes and




excessive scales and shall be tested for mechanical properties and

physical composition.

The assembly shall be manufactured at the factory into the

minimum number of segments ( not more than two) within

limitations suitable for transportation.

Further, the method of construction shall be such that the critical

welded joints, where the stress concentration occurs (Circular

joints between stay ring and spiral case segments) shall be

finished at factory and shall be stress relieved.

Special precautions shall be taken by the supplier to prevent

cracking in the spiral case plates adjacent to the stay ring bolting

flange faces due to the discontinuity in the stay ring acting as a‘stress raiser’.

The stay ring shall be of “Parallel plate” design. The stay vanes

shall be welded to the flat plates with full penetration welds. The

stay ring shall be designed and shaped to direct the water flow

with a minimum frictional loss and to eliminate vibrations. The

trailing edges of stay vanes shall be shaped so as to minimise

vortex formation.The surface of stay ring and the welded joints in contact with

water shall be ground to a smooth finish.

Holes not less than 100 mm and preferably 150 mm in diameter

shall be provided in the lower stay ring to facilitate the placing of

concrete. Suitable provision shall be made for closing the holes

after the concrete is placed. Suitable grout holes with plugs shall

be provided in the stay ring as required for concreting and

grouting. Air vent holes shall be provided through the webs in

isolated pockets.

The stay ring shall be designed to withstand all forces acting

upon it, hydraulic conditions during hydrostatic testing and

operation of the turbine including the loads due to the generator




and rotating turbine parts with the spiral case empty. The stay

ring shall also be designed to withstand the forces transmitted to

it from the spiral case under abnormal condition pressure. Under

these conditions, the maximum stresses induced shall not exceed

67% of yield point stress of the material used.

Welding of the stay ring shall be in accordance with requirements

of these specifications. The weld shall be ground smooth to 3.2

micron (roughness). All other areas of the stay ring in contact

with water shall be finished to roughness not exceeding 6.4

microns (roughness).The stay ring shall be stress relieved before

machining.

All butt welds and welds to spiral case plate shall be examined by100% Radiography Test and stay vane to shroud welds shall be

examined by Ultra sonic Test. All welds shall also be checked by

Penetration Test or Magnetic particle test. Any defects discovered

shall be repaired in accordance with relevant code.

The stay ring shall be painted. All paint applied for protection of

wetted surfaces during shipment shall be removed at site and

surfaces shall be prepared and painted according tospecifications.

It shall be possible to perform site welding of spiral plates

without pre-heating. Also, the quality of the steel shall be such

that post weld heat treatment is not required.

The circumferential joints shall be designed to give a strength

equivalent to that of the longitudinal joints of corresponding

sections.

For convenience in transportation and erection at site, each

divided segment of the assembly shall be provided with bases for

installation and lifting hooks.

Spiral case shall have a manhole of at least 600 mm. internal

diameters, for access to facilitate inspection. The manhole shall




be provided with door made of steel plate. It shall be fixed to

spiral by means of bolts. The manhole cover shall also withstand

maximum water pressure.

Spiral case shall be provided with pipes for the following

purposes (but not limited to) with necessary valves.

_________________________________________________

Sr. Description Quantity Nos.

_________________________________________________

I) Drain pipe for the spiral case. …1

ii) Piping for the by pass valve of the

Butterfly valve. …1

iii) Stainless steel piezometer taps for

the purpose of flow measurement

during operation : …4

iv) Any other piping & tapping

required to make the equipment

complete …Lot

The foundation items such as sole plates, packing, levelling

jacks/screws, tie rods and turn buckles etc. in sufficient quantity

shall be supplied along with spiral case.

Expansion joint, thrust collar, air release valve and such other

assemblies which are necessary shall be provided.

ii) HYDRAULIC PRESSURE TEST ON SITE

A hydraulic pressure test of the spiral case and stay ring assembly

shall be conducted before concreting. The suitable test pressure

(24Kg /cm²) shall be gradually increased in steps. The final

pressure shall be maintained for sufficiently long time (30




minutes) to allow inspection of field joints for leaks. The

pressure shall then be reduced. This pressure cycle shall be

repeated three (3) times. The rectification /repairs shall be

carried to stop the leakage notified. After completion of

repairs/rectifications, the assembly shall again be subject to

pressure cycles. The hydraulic pressure tests shall be treated as

successfully completed only if no leaks are notified and no

visible damage to spiral case and stay ring is seen.

The supplier shall provide one set of test equipment for

performing the hydraulic pressure tests on stay ring, spiral case

assembly.

The test equipment shall include the following:* One test cone for the spiral case inlet.

* One test ring for the inner diameter of the stay ring with

seals etc.

* One pump-motor set of adequate capacity and pressure

flow and pressure gauges, dial gauges, isolating valves,

relief valve etc., required to perform the pressure test and

all pressure test equipment shall become property of thepurchaser.

The supplier shall provide the services of experienced

personnel and all materials and tools necessary for taking

measurements and conducting the pressure tests.

Upon successful completion of hydraulic pressure test, the

supplier shall submit the copies of the pressure test report,

which should detail the following

* The time of commencing the preparation of the test and

completion of the major activities.

* Description of equipment.

* Test conditions.




5.5.2 DISCHARGE RING

The discharge ring shall be of plate steel welded construction and

sectionalised as necessary to facilitate shipment and handling. It shall

be of heavy section and adequately ribbed externally to secure proper

anchorage to the concrete and to prevent distortion.

The discharge ring shall have a flange at the top for bolting to the

bottom ring or stay ring. The lower end shall have either a flange for

bolted connection or an extension for welded connection to the draft

tube cone. The necessary foundation bolts shall be supplied for

anchoring the foundation ring to the concrete and adjusting jacks with

steel bearing plates shall be furnished to facilitate levelling duringinstallation.

Suitable grout holes with plugs shall be provided in the discharge ring,

as required, for concreting and grouting.

The lower end of the discharge ring or alternatively the draft tube cone

flange shall be machined to form a ledge for support of the runner

during installation and also when disconnected from the generator.

5.5.3 GUIDE VANES AND REGULATING APPARATUS

The number of guide vanes and the number of runner blades shall be co-

ordinated in a manner to ensure that the turbine will operate without

objectionable pressure pulsation and vibration.

The guide vanes shall be of stainless steel casting having wear and

corrosion resistance properties. The vanes shall be uniform in shape and

their cross sections shall be such as to obtain a streamline flow of water

with a minimum of friction and hydraulic disturbances during operation

of the turbine. Each guide vane stem shall be provided with greaseless

self lubricated bearings and a water seal. All bolts and nuts for the seals

shall be of bronze or stainless steel. The system of bearings and water




seals provided including the construction details should be fully

described in the bid.

The turbine guide bearing shall be designed so that guide vanes will not

be lifted up by water pressure of leakage water from the lower portion.

The guide vanes shall be accurately machined and ground so smooth

that surface roughness shall not exceed 6.3 Ra. All vanes shall be

interchangeable.

The guide vane regulating apparatus shall be of ample strength to

withstand the maximum forces imposed on it under most severe

operating conditions. All parts having relative contact in motion shall

be provided with self-lubricating greaseless bearings. The whole

mechanism shall be designed to have “closing tendency” and minimumof lost motion and friction.

A suitable shear pin or breaking link shall be provided between each

vane stem and the regulating ring and shall be strong enough to

withstand the maximum operating forces, but which will break in the

event of excessive forces acting in either the opening or closing

direction and will protect the rest of the mechanism from damage in case

one or more of the vanes become blocked. Locking device, oil pipelines,valves, pressure gauges, limit switches etc shall be provided.

As a precaution against damage when a guide vane is free to rotate due

to breakage of a shear pin or link, the vane shall be restrained from

excessive movement by means of a friction device located on the vane

stem, which provides a restraining force between the levers. The

friction device shall be designed to resist independent movement of the

vane for the maximum hydraulic torque at any guide vane position. The

friction device mechanism on each vane shall be tested during

installation to ensure performance as designed.

A manually adjustable stop shall be incorporated, with which the motion

of the guide vanes in the opening direction can be positively limited.




5.5.4 SERVOMOTORS

Turbine shall be provided with two (2) Nos. oil pressure operated double

acting hydraulic servomotors. The combined capacity of the

servomotors shall be sufficient to supply the maximum force necessary

to operate and hold the guide vanes at any desired position at the

minimum oil pressure.

Further, the servomotors shall be rigidly supported and shall be capable

of moving the guide vanes from a completely closed position to a fully

open position in one stroke and vice versa. Cushioning shall be

provided in the last ten percent (10%) of the stroke in each direction.

The servomotor cylinders shall be provided with flanges for connecting

oil piping. Connection for pressure gauges shall be provided at each endof each cylinder. An air vent and a drain cock shall be provided on each

servomotor for draining purpose.

The inner surface of the cylinder shall be bored accurately to a uniform

diameter. The surface finish shall be such that roughness shall be within

1.6 micron.

The piston fitting shall be such as to allow the piston to travel, freely and

smoothly but to reduce oil leakage past the piston to an absoluteminimum. Chevron type packing shall be used for this purpose. Each

piston shall be fitted with not less than three piston rings, suitably

shaped to give close contact and uniform pressure on the cylinder walls.

The servomotor piston rod shall be provided with lubricated bearings.

Lubrication shall be arranged to ensure that lubricant is admitted to high

pressure areas regardless of vane position. This piston rod shall be

arranged for adjustment of stroke. The connecting rod shall be of forged

steel and of uniform cross section. A specially designed and a strong

joint using accurately ground pin of hardened steel shall be provided

between piston rod and connecting rod. The joint shall be provided with

greaseless bearings of self-lubricating type.




The servomotor cylinder shall be designed and so located that the force

for moving the turbine guide vanes shall be divided approximately

equally between the two cylinders and shall be applied in substantially

equal magnitude to opposite sides of the vane regulating ring and

tangentially to the ring.

Provision shall be made for adequate field alignment of the servomotors

using levelling or dutchmen (shim) plates supplied by manufacturer.

The servomotor flange shall be dowelled in the field to its mounting

flange.

A manual locking device of a simple construction to permit locking the

guide vanes in the fully open and closed positions and capable of

withstanding safely the full operating force of the servomotors shall beprovided at the servomotors. The device shall be such that it can be

easily engaged and disengaged by one man. Besides, limit switches

(with electrical contacts suitable for operating on 220 V D.C. system)

shall be provided, to indicate the fully open and fully closed positions of

the guide vanes and for using in the control circuit as interlocks for

starting the unit. All contacts shall be wired up to terminal box placed in

the turbine pit.By-pass connections, equipped with orifices and/or adjustable needle

valves, with a secure means of locking the adjustment, shall be provided

on the servomotors to retard connections shall be fitted with check

valves to prevent sluggish movement during opening the guide vanes

from the fully closed position.

A suitable pointer and graduated scale shall be provided to indicate the

stroke of the servomotor (i.e. % guide vane opening from the closed

position) in steps of 5 %. The scales shall be calibrated in the field and

marked “closed” at one end of the scale and “opened” at the other end.

The servomotor stroke must be capable of manual adjustment. Means

for positively locking the adjustment must be provided.




Servomotor cylinders and all the oil piping and valves in the system

shall be shop tested to a pressure equal to 150% of the design pressure

of the oil system.

5.5.5 RUNNER

The turbine runner shall be integrally cast in one piece. The material

used shall be proven for erosion and corrosion resistant properties. The

contours of the runner vanes shall be accurate and shall be hand finished

so that the vane profile precisely conform to the model design within

the tolerances set out in IEC publication 193, Chapter - IV.

The runner vanes shall be evenly and symmetrically spaced.

The surface of the runner in contact with water shall be ground to asmooth finish so as to achieve surface without any humps or hollows.

The surface roughness shall be :

Entire blade high pressure side surface and low pressure side surface

except following……………………………3.2 Ra.

Blade low pressure side surface and band inner surface beyond outlet

width corresponding point …………… ….1.6 Ra.

Entire crown inner surface and band inner surface except above………………………………………………3.2Ra.

The runner band, the crown and shaft coupling surfaces shall be

accurately machined and ground. If required these records shall be made

available to purchaser on request.

To prevent seizure of runner during starting and stopping the vertical

running clearance between the runner band and the discharge ring shall

be zigzag.

Provision shall be made to permit aeration of the draft tube through the

runner crown.

Runner and turbine shaft shall be connected by coupling. To facilitate

replacement of runner in future and interchangeability, connecting parts

shall be accurately finished and use of template and keys shall be




provided. Connecting bolts shall be suitably covered to minimise

resistance when rotating in water.

The runner shall be designed to withstand safely the dynamic stresses at

maximum runaway speed.

The runner shall be designed to support its own weight and the height of

the turbine shaft when disconnected from the generator shaft with the

runner resting on a shoulder of the discharge ring or draft tube liner

flange.

The supplier shall provide complete arrangement of runner removal

through the generator stator.

5.5.6 HEAD COVER AND BOTTOM RINGHEAD COVER

It shall be of a heavy construction, adequately ribbed and so shaped as to

give rigid support to the guide bearing and the regulating ring.

All welds shall be fully penetrated and stress relieved. Only the radial

ribs, if used, may be fillet welded.

The head cover shall be designed to withstand safely and without

detrimental deflection the maximum water pressure and all other forcesacting upon it. The deflection of the head cover shall be small enough to

obviate the possibility of rubbing of the guide vanes and bending the

vane stems. The underside of the head cover shall be designed to

minimise friction and eddy losses between the head cover and the

runner. The space between shall be adequately drained to relieve water

pressure and to minimise hydraulic thrust. Head cover shall be in one

piece or divided in minimum possible number of parts. Construction of

head cover shall be such that the parts such as turbine bearing, shaft seal

etc. shall be easily accessible for easy maintenance without requiring the

head cover to be dismantled.

The head cover and bottom ring shall be provided with replaceable

stainless steel liners between them and runner.




The head cover assembly shall be provided with machined sets for the

turbine guide bearing, guide vane regulating ring, shaft seal, guide vane

and any other equipment. The part of the head cover, which constitutes

the guide bearing support structure, shall be so designed as to provide a

rigid support. A retaining ring or pads shall be furnished to prevent any

lifting tendency of the guide vane-regulating ring.

The seat for the guide vane regulating ring shall be provided with a

renewable stainless steel liner accurately machined so as to ensure

minimum lost motion and friction in the operation of the guide vane

regulating ring.

At least four (4) Nos. opening for inspection shall be provided in thehead cover to allow entry and check clearance of the runner crown seals.

The opening shall be provided with doors which are bolted to the head

cover.

The lower surface of the head cover shall be machined to provide

smooth surface to the water passage at the entrance to the runner.

A renewable stainless steel seal ring or rings, accurately machined to

form a master seal with the runner crown and shaped to reduce leakage,

shall be secured to head cover. Any hydrostatic pressure built up behind

the seal rings shall be relieved through built-in pressure relief holes.

The seal rings (on head cover) may be of the same composition as the

sealing face on the runner provided it is at least 50 B(Brinnell) lower in

hardness. Leakage of water through the seal shall be directed to the

draft tube without building pressure under the head cover.

Renewable stainless steel facing plates shall be provided on the lower

face of the head cover between the stay ring and runner seal. The

surface finish of the facing plates shall be smooth.




Supplier shall provide isolating valves, check valves and all necessary

piping and fitting within the turbine pit for air, leakage water, air

admission etc.

A minimum of three (3) Nos. piezometer connections shall be provided

on the head cover. These shall be connected to a common manifold and

equipped with suitable valves and a pressure gauge. These connections

shall be arranged so that fluctuations of water pressure under the head

cover can be measured. The pressure gauges shall be mounted in the

turbine pit.

Walkways around the head cover and turbine bearing shall be provided

with gratings or suitable opening to facilitate visual inspection of equipment located below the walkways.

For welding purposes, the head cover shall be considered as a pressure

vessel.

All butt welds shall be examined by 100% UT or RT. All other welds

shall be fully examined by PT or MT. Any weld defects shall be

repaired in accordance with these specifications.

An adequate number of eye bolts shall be supplied to lift the head cover.The head cover shall be designed to pass through the generator bore in

the place during erection and dismantling and with the runner and shaft

in place.

The supplier shall furnish an air valve piping within the turbine pit,

terminating in standard pipe flanges at the limits of the pit liner. All

components of the automatic air valves shall be made of non-corrosive

material.

Balance pipe shall be provided with a valve having adjustable opening at

suitable position between the head cover and upper draft tube liner.

Efficient draining arrangement for leakage water from guide vane shall

be provided and described by the supplier.




Draft tube liner shall extend upto hydraulic profile with exit velocity of

less than 4m/s at maximum discharge.

The UDTL shall be of stainless steel and machined accurately for

connection to the discharge ring. It shall extend for sufficient distance

below the centre line of the distributor to protect the concrete around the

draft tube from scouring and pitting.

A watertight and airtight manhole door, having a clear opening not less

than 750 mm, complete with studs and nuts, shall be provided in the

draft tube liner.

A sufficient number of levelling screws, jacks, turn buckles and hold-

down bolts shall be provided to permit centring, levelling and securely

holding the liner, both vertically and laterally, during assembly andwhile concrete is being placed. Sufficiently large holes shall be

provided in the draft tube liner for placing of concrete, in difficult

position.

These holes shall be plugged and ground flush after the placement is

complete. Also, suitably spaced grout holes shall be provided to

facilitate final low pressure concrete. These grout holes shall be

plugged and ground flush after grouting is completed.Upper draft tube liner (UDTL) shall be provided with following piping

and necessary valves:

* Test cock for water level detection.

* Piping for mounting the balance pipe.

* Drain pipe for leakage water from guide vanes.

* Piping for water level detector.

* Piping for measuring the water pressure in the draft tube.

* A compound pressure gauge for measuring pressure in draft tube.

* Anchors, stiffeners, turn buckles, etc.

Drain pipe with water valves shall be provided for draft tube at the

lowest point. The drainage pipe shall be taken up to dewatering sump.

The drain valves shall be “gate type” and shall be provided with




sufficiently long stem and on hand wheel suitable for operation from the

valve floor.

The supplier shall provide a strong aluminium platform to be located in

the upper draft tube liner (UDTL) for access to the runner. Provision

shall be made in the liner for the support of this platform. The platform

shall be so constructed that the same can be installed and removed from

manhole.

Steel lined outlet of draft tube shall be connected to the tailrace. Steel

for this pipe shall be same as that of draft tube and suitable to withstand

maximum pressure during transient and steady state conditions. All

fixtures, stiffeners, anchors, supports, rail line for erection etc. shall be

provided for them.

5.5.8 TURBINE SHAFT:

It shall be provided with integrally forged coupling flanges for

connecting to the generator shaft and to the runner. It shall be of ample

size to operate at any speed up to the maximum runaway speed without

detrimental vibration or distortion and to transmit the maximum output.

The maximum stress induced under such abnormal condition shall notexceed 67% of the yield point stress. Besides, the shaft shall be

designed to withstand safely the shocks and abnormal stress induced

under conditions of line to line short circuit, faulty synchronising and

turbine trip-outs without harmful vibrations or distortions.

The shaft system shall be designed so that the first critical speed shall be

at least 1.25 times the maximum steady state runaway speed, which may

occur under most unfavourable transient conditions of turbine.

The shaft shall be accurately machined all over and polished smooth in

the portions where guide bearing and the shaft seal sleeve are fitted such

that surface finish is within 0.4 microns.




The shaft shall be bored axially to a diameter of atleast 150mm

throughout its entire length to facilitate baroscopic inspection of the

shaft material.

The sleeve shall be made in two halves removable and renewable and

securely fastened to the shaft. After assembly on the shaft, the sleeve

shall be accurately machined and polished. The sleeve shall be made of

non-nickel bearing stainless steel. Effective means shall be adopted for

the prevention of corrosion of the shaft underneath the sleeve. Suitable

oil baffles and water detectors shall be provided between the main guide

bearing and the shaft seal.

The amount of shaft run out shall be checked by rotating the finished

turbine shaft in a lathe or lining device in factory. The amount of runoutshall not exceed the recommended values in NEMA standard No. MG-

5.1.-3.04 (R 1979) for vertical hydraulic turbine generator shaft run out

tolerances. Two bands shall be marked on the shaft for reference during

alignment. The bands shall be concentric with the shaft and polished to

a finish of 0.4 micron (roughness). The turbine - generator shaft

coupling shall be designed in accordance with ANSI B 49.1 The lower

shaft coupling to the runner shall be dimensioned so far as is practicablein accordance with ANSI Standards.

Immediately above the bearing housing a circumferential line shall be

inscribed on the shaft and an adjustable pointer shall be mounted on the

bearing housing opposite this line to indicate if any axial movement of

the shaft occurs, and to permit re-alignment after thrust bearing

dismantling.

The turbine supplier shall be responsible for the final reaming of the

coupling bolt holes, aligning of the turbine and generator shaft and

conducting the combined run-out to NEMA Standard No. MG-5.1-3.04

(R 1979).

The field alignment procedure for shaft and bearings shall be approved

by the Purchaser prior to the start of assembly. Under the conditions of




rotational test, the run outs at the turbine bearing shall not exceed 0.10

microns per meter length of shaft between the generator top guide

bearing and the turbine guide bearing.

Hydraulic jack for pre-stressing of shaft couplings bolts, head cover &

bottom ring shall be provided.

5.5.9. SHAFT SEAL

The axial movement type shaft seal shall be provided below the guide

bearing to prevent the leakage of water along the shaft. The sealing

shall be achieved by rings of tough fibre and metal carbon one rotating

with the shaft and other stationary. The seal components shall be

hydraulically designed to suit the worst operating conditions. Theloading of the seal faces may be regulated by springs. Any wear, which

may take place, shall be restricted to seal components and not the shaft.

All seal components including seal faces may be manufactured in

suitable number of parts to facilitate, both initial assembly and

maintenance. The rings shall be of self-compensating type and shall

automatically adjust for wear during its full operational life. The

wearing of the seal shall be minimum with a guaranteed life of at least20,000 operating hours. A wear indicator shall be provided to monitor

the wearing rate.

The shaft seal shall be so designed as to prevent the high pressure water

flowing out during turbine operation.

A secondary maintenance-sealing device shall be provided to allow the

carbon seal rings to be serviced. This secondary maintenance-sealing

device shall prevent leakages along the shaft when the turbine is

stationery and subject to tail water pressure and shall be compressed air

operated.

Suitable means, such as lifting bolts and backing out studs, shall be

provided to facilitate installation and removal of shaft seal parts.




The shaft seal shall be arranged for water lubrications. Two or more

connections for water shall be provided. These shall be evenly spaced

on the periphery to admit supply of clean water at a sufficiently high

pressure to remove dirt and foreign matter from the seal. The supplier

shall be responsible and shall provide the necessary equipment to

maintain the quality and quantity of sealing water requirements.

The supplier shall provide the necessary water filtration equipment,

piping and valves, including pressure-reducing valves, if required. The

piping and fittings within the turbine pit terminated by unions or flanges

shall be continued outside the turbine pit. Piping shall be provided with

a sufficient number of unions to permit easy removal.

All bolts, nuts, screws and hardware used in connection with the shaftwater seal shall be of bronze or stainless steel.

The shaft seal housing shall be made of wear resistant material of high

durability and shall be sufficiently rigid.

5.5.10 GUIDE BEARING (SEGMENT TYPE)

The turbine guide bearing shall be “segment” type and shall be self-

lubricating i.e. lubrication shall be automatically achieved by means of centrifugal action of the rotating shaft. The use of any external electrical

pump for circulation of oil shall not be made.

The bearing design shall be such that no water shall enter the lubricating

system via the shaft seal and there shall be no appreciable loss of oil by

leakage or by overflow from any part of the oil system under any

condition of operation including starting, stopping and over speeding

during trip outs.

Further the bearing shall be designed to operate satisfactory (i.e. without

any damage) under following conditions:

i) Continuous operation at any speed between 30% and 110% of

rated speed at no load and maximum load.




ii) For 15 minutes at maximum runaway speed.

iii) For 15 minutes, upon sudden rejection of maximum power and in

continuation thereafter till the unit comes to standstill as a result

of tripping and interruption of cooling water supply.

The bearing area and the bearing oil reservoir capacity shall be such that

temperature of the segments shall not exceed 70oC under worst

conditions of operations.

The lubricating oil shall be cooled by means of heat exchangers placed

outside oil reservoir. The heat exchanger shall be tested in the shop and

before assembling on site under a pressure equal to 200% of the

maximum operating pressure for a period of two hours.

The bearing shall be located as near to runner as possible consistent withthe distance assumed in shaft system analysis and keeping in view the

space required for accessibility and maintenance of the shaft seal. The

construction of the bearing and bearing oil reservoir shall be such that

inspection, adjustment or dismantling and removal of the bearing

segments shall be possible without requiring dismantling of the head

cover and/or disturbing the major parts of the turbine.

The mechanical design of the bearing shall take into account theabnormal radial forces during starting, stopping, trip-outs and running at

runaway speed of the unit and also provide axial movement of the shaft.

The bearing segments shall be truly cylindrical in shape, the cylinder

formed by assembly. The segments shall be concentric with the shaft,

the bearing segments shall be of heavy sections and shall be provided

with a continuous, strong and rigid supporting arrangement. The

method of construction shall be fully described in the bid.

The adjustment of the bearing segments by use of shims or radial studs

shall not be acceptable.

The bearing oil reservoir shall have sufficient capacity to supply the

required amount of oil to the turbine guide bearing and provide cool oil

to the bearing under all conditions of load. The bearing design shall




prevent the leakage of oil down along the shaft. Piping for filling oil in

the bearing and reservoir shall be separate from the drain piping.

The supplier shall supply and install the following indicating and

protection devices for guide bearing.

- One dial type thermometer to indicate the hottest part of the

bearing.

The thermometer shall have two (2) sets of separately adjustable

contact suitable for operating alarm and tripping circuits at 220 V

D.C. The thermometer indicator shall be mounted on Gauge

panel.

- The resistance temperature detectors R.T.D (Pt 100 Ohms at 0oC)

One for bearing segment and one for oil indication and recordingthe temperatures at unit control board.

- One direct reading water flow meter with two electrical contacts

(suitable for operation at 220 V D.C. for signalling low cooling

water supply / stoppage of cooling water supply.

- One oil level gauge properly graduated marked in litres and high

and low level adjustable alarm contacts with 220V.D.C. contact

rating.

5.5.11 PIT LINER, WALKWAYS, PLATFORMS AND STAIRWAYS

A pit liner of plate steel welded construction with servomotor pockets if

requested shall be provided for the full height up to generator lower

bracket. It shall be made in sections as necessary for shipment. The

internal diameter of the pit liner shall be such to allow the removal of

the head cover, the turbine runner and regulating ring easily.

The bottom of the pit liner shall be prepared for welding to the stay ring

with full penetration welds. The pit liner shall be provided with

sufficient number of stiffeners and anchors so that distortion of the liner

shall not occur during life time operation of the unit.




If servomotor pockets are provided a suitable arrangement to transmit,

the servomotor reaction forces through the pit liner to the surroundings

concrete shall be made.

The section of the pit liner containing the servomotor pockets shall be

stress relieved and the surfaces of the servomotor support plates shall be

machined after stress relieving.

Working, operating and inspecting walkways and platforms complete

with floor plates and/or gratings, stairs and handrails shall be furnished

in the turbine pit to provide convenient and safe access to all operating

equipment and point of lubrications if any. The design of the floor

plates, gratings, stairs and handrails shall facilitate easy removal to

permit free access.Monorail and a electric hoist of adequate capacity shall be provided in

the turbine pit for easy handling of the guide vanes and other parts.

5.5.12 Tools and tackles required for handling guide bearing shall be provided

by Supplier.

5.5.13 Test equipments of all kinds, which are necessary for erection, testing &commissioning at site shall be provided.

5.5.14 Turbine junction boxes suitable for mounting on barrel wall outside

shall be provided.

5.5.15 Control and power cables:-

All power cables for local control centres to equipment, local control

centres to unit control boards and up to distribution centres provided by

the purchaser shall be provided by the supplier, all power cables

between two equipment covered under the scope of this contract shall be

provided by the supplier. All the control cables between equipments

covered under the scope of this contract shall be provided. Racks, cleats,




ferrule, glands etc for entire system of equipment covered under the

scope of supply of the supplier shall also be provided by the supplier.

All power and control cables shall be of FRLS copper conductor type.

5.5.16 Oil, grease, lubricants sufficient for first filling and 25% spare quantities

shall be supplied.

5.5.17 All accessories viz. sole plates, foundation & anchor bolts, platforms,

ladders, guards, handrail, bolts, nuts, turn buckles etc complete required

during installation shall be provided by the supplier.

5.5.18 Thermometers, thermal relays, oil level gauges and relays, waterpressure gauges and relays etc. to install near the equipment, on Gauge

panel and Unit control board shall be provided by the Supplier.

5.5.19 Oil leakage system if needed (requirement shall be justified at bidding

stage) complete with tank, motor-pump sets, pipes, valves, level

switches, gauges etc.

5.6 GOVERNING SYSTEM

Turbine shall be provided with electronic PID governor to control the

turbine during starting, stopping and operation at any load.

5.6.1 The governor system should have following qualities:

i) Fast acting

ii) Stable (No hunting).

iii) Reliable

iv) High sensitivity.

v) Easy control.




The governing system shall be designed to perform the following

functions.

1) Unit start-up.

2) Idling and synchronisation

3) Normal stopping and emergency shut-down with necessary

monitoring and safety functions.

In addition the governing system must allow the operation of the unit

either in ‘frequency control’ (i.e. speed governing) function or in ‘output

control’ function. In ‘frequency control’ function, the frequency (and

therefore the operating speed) shall be maintained at set point, when the

unit is in isolated operation or in idling mode. In output controlfunction, the power output of the unit shall be maintained at set point.

Configuration

The governing system comprising of oil pressure system, the hydro

mechanical cabinet (HMC) i.e. actuator and the electronics shall divide

functionally so as to achieve, “Local” i.e. ‘Manual Control’ or remote

control of the unit.

The manual control shall be directly from the HMC i.e. actuator cabinet.The remote control shall be from Unit control board or from SCADA

system.

The speed governor shall have the following facilities and performance.

1) Speed adjusting range 85 - 105%

2) Adjusting range of permanent droop 0 - 6%

3) Adjusting range of incremental

momentary speed droop 0 - 50%

4) Adjusting range of time constant

of damping 0 - 15 sec

5) Governor dead band 0. 02%




6) Gate setting operation

The speed governor shall be capable of gate setting operation by

the load limiting device and will be capable of easily changing

over from automatic operation to gate setting operation or vice

versa.

7) Gate opening regulating device

This device shall be capable of the following control.

a) Starting gate opening control.

b) Control of maximum output gate opening.

8) Protective device:The protective device shall be capable of fully closing the guide

vane in case that a trouble occurs in the speed governor and shall

stop the turbine quickly.

5.6.2 Both the speed control governor and power output governor shall

actuate the same servo-positioner through the opening set point.

5.6.3 The electronic PID controller’s behaviour shall be enhanced by special

means such as disturbance super position and secondary variable super

position.

Speed sensing

The speed sensing for governor operation shall be taken from toothed

disc method or via transducers using residual remainance.

5.6.4 CHARACTERISTIC PARAMETERS OF PID- CONTROLLERS.

(Definitions as per IEC 308/1970)

i) Permanent Droop (bp)




vii) Time setting range.

a) Speed setting -between 20 and 100 s

b) Power output -between 20 and 80 s

setting for full travel of

servomotor

c) Limiter. - between 20 and 80s

for full travel of

servomotor

viii) Control Inaccuracy(ix/2)

speed control ix/2<2 x 10-4

Power output control ix/2 <1 x 10-2

ix) Parameters of servo positioner.

Input :Electrical signal or position of pilot servomotor.

Output: Relative position of the main servomotors

For servo positions, the following applies:-

a) Minimum servomotor opening and closing times Tg and Tf shallbe separately determined to satisfy water hammer and over speed

limitations. The limiting orifices shall be so dimensioned that the

actual stroke times in the presence of the highest supply pressure

and lowest required regulating capacity is not lower than the

allowable stroke time.

b) Time constant (Ty) of the main servo positioner to be introduced

in digital stimulation system shall lie between 0.1s and 0.25s.

Near the zero displacement, higher values of Ty shall prevail due

to overlap and grooves.

c) Servo positioner inaccuracy in follow up arrangement (ia/2)

which has a major influence on dead band shall be kept small i.e.

< 0.2% for the complete servo positioning system.




d) Control system dead time constant (Tq) shall be less than 0.25s.

e) Dynamic response of servo positioner.

Setting of servo positioner shall be so chosen that the dynamic

response of servo positioner corresponding to a damping ratio (D)

between 0.8 and 1.1 is achieved.

5.6.5 MANUAL CONTROL

Manual control of setting of turbine power directly via the actuators by-

passing the governor control loop shall be provided. In that case, the

safety of unit shall rest with over speed protection.

5.6.6 FOLLOW - UP CONTROLSFollowing follow-up controls shall be provided:

i) The power output governor command signal shall follow the

actual power output signal in the speed control mode.

ii) The speed command signal shall follow the actual frequency-

signal in the power output control mode or during the start up

phase (speed command signal pre-adjustment).iii) The manual control set point shall follow the actual actuator

position in the various control modes.

iv) In case of remote control, respective local control shall follow the

respective command signals.

v) It shall be possible to adjust the pre-opening of varying heads to

minimise start up times.

5.6.7 OPTIMISATION CONTROL

Special control configuration shall be provided to optimise the system

with respect to overall plant efficiency, smooth running or other criteria.




i) Purpose

Oil pressure unit system shall be used for operation of the guide

vane.

ii) System

a) The pressure oil supply system shall comprise of 2 sets of

pressure oil pumps directly coupled with the 400V A.C.

motors (1 set for normal operation and 1 set for stand-by).

1 set of sump tank, 1 set of pressure tank and other

accessories.

b) Compressed air required shall be taken from one of the

two Air receivers. Necessary valves pipes etc. required

shall be provided by supplier.c) Operation method of the pressure oil pump shall be of the

continuous operation type using unloader valves. When

the normal oil pump stops during operation of turbine or in

case of the first stage of oil pressure drops, stand-by pump

shall start automatically.

d) Changeover between the main and stand-by pumps shall

be carried out through the changeover switch provided onthe motor control panel and shall operate automatically. In

case of drastic depression of oil level, both pumps shall

operate simultaneously. Besides, starting and stopping

shall be carried out not only automatically but also

manually from the motor control panel and from unit

control board. Operating mechanism shall be oil/water or

alternatively oil/oil will be considered.

iii) Composition and Design

One set of the oil pressure unit system shall comprise of the

following items.




Pressure oil pumps . . . 2 sets

(one for normal and one for stand-by)

a) Each pressure oil pump shall be vertical shaft screw pump.

The oil flow rate per pump at the maximum delivery

pressure shall be sufficient for operating the guide vanes

from the fully opened state to the fully closed state without

supply of pressure oil from the pressure tank. Each of

these pumps shall be of capacity sufficient to cover

leakage losses with a safety margin in excess of 2. Design

of pressure tank shall be according to draft TC4/WG

14.4(Sec.102 of Feb.88)

b) The normal operating oil pressure shall be adequate.System shall have sufficient oil under pressure to operate

servomotor in close-open-close or open-close-open cycles

(three operations) of guide vanes without requiring

charging of system.

c) Each set of normal and stand-by pumps set shall be

provided with following accessories.

i) Unloader valve 1 setii) Safety valve 1 set

iii) Non return valve 1 set

iv) Strainer 1 set

v) Induction motors 2 sets

(One for normal and one for stand-by)

Each motor shall be vertical shaft, 400V, 50 Hz., 3

phase AC induction motor and shall be used for

driving the pressure oil pump.

vi) Motor control panel

for oil pressure system 1 set

iv) Pressure tank/air oil accumulator 1 No.




i) Automatic oil level control device 1 set

ii) Oil level gauge (with stop valve

with check valve) 1pce.

iii) Oil pressure gauge (with stop valve) 1pec.

iv) Safety valve (if any) 1 pec

v) Solenoid valve for air supply 1pec.

vi) Oil supply valve and oil drain valve 1pec

vii) Oil pressure relays 1 set

v) Sump tank

a) Total capacity of the sump tank shall be 120% of

oil volume in the pressure oil system. The sump

tank shall be designed to allow drainage of complete hydraulic system into the tank. It shall

also be designed to allow a complete emptying for

maintenance purposes and to remove the dew point

of water, e.g. by providing a slightly inclined

bottom.

Cooling/heating of the system oil shall be provided

to limit oil viscosity variations. Separate oil vapourexhaust equipment shall be provided.

b) Sump tank shall be provided with a cooler so that

oil temperature will not become too high. Oil/water

cooling coils of cooler shall be made of seamless

steel pipes and shall be free from water leakage.

c) A manhole shall be provided for inspection.

d) The following accessories shall be supplied.

i) Dial type oil level gauge with

alarm contact 1 pec.

ii) Oil level relays (for low oil level

warning and for high oil level warning) 1 pec.

each




iii) Dial type thermometer. 1pec

vi) Pipes and valves.

Pipes and valves necessary for all pressure supply system,

and also a complete set of flange couplings, bolts, nuts and

packing required shall be supplied.

5.7 ELECTRICAL EQUIPMENT

CONTROL AND MONITORING DEVICES.

These shall be provided as per the Annexure V-2 through V-5 appended

to this section. The control and monitoring devices shall include but not

limited to following:

1. Automatic operation control devicesa) Solenoid valves.

i) For opening and closing of the

inlet valve 1 pec.

ii) For starting and stopping of unit 1 pec.

iv) For the brake of the generator 1 pec

The solenoids shall be so arranged that they do notremain continuously energised in whichever case

the unit is running or in standstill.

b) All necessary limit switches 1 set.

c) All necessary auxiliary relays 1 set.

d) All necessary relay valves 1 set.

e) All necessary piping and valves 1 set.

2) Turbine control board (Gauge Panel)

The turbine control board shall be of cubicle type of steel

plates and shall be arranged in line with the speed

governor cabinet. In front of the turbine control board, a

name plate shall be mounted.




The turbine control board shall be capable of manual

operation of the turbine and auxiliaries such as flowing of

cooling water, opening and closing of the inlet valve of the

turbine, starting, stopping, and operation of the brake, etc.

Manual operation shall be of such type as to actuate the

solenoid by operation of the switches on the turbine

control board individually. The control board shall house

the solenoid valves etc., shall be provided with the

measuring instruments, operation indicators, on the front

surface and shall keep sufficient space so that inspection

and adjustment can be carried out easily. The turbine

control board shall comprise the following.a) Control switch change-over switch 1 No.

(local-remote)

b) Manual operation switches for :

i) Solenoid valves for opening and

closing of the butterfly valve. 1 No.

ii) Solenoid valve for starting andstopping of turbine. 1 No.

iv) Solenoid valve for the brake of the

generator 1 No

v) Other solenoid valves housed in

turbine unit control board 1 set

vi) Limit switches 1 set.

vii) Auxiliary relay. 1 set.

viii) Piping and valves. 1 set.

ix) Indicating lamps. 1 set.




Oil pressure relays :

i) For starting condition of turbine.

(operates when oil pressure for

guide vane operation is same

as or higher than the specified

value.) 1 No.

ii) For alarm at oil pressure drop 1 No.

iii) For quick stop at operating oil

pressure drop 1 No.

iv) For start and stop of the stand by

oil pump 1 No.

v) For oil level control 1 No.vi) For Actuator pressure. 1 No.

vii) Water pressure relay for spiral

case pressure. 1 No.

Instruments :

i) Water pressure gauge for steel

lined shaft 1 No.ii) Water pressure gauge for spiral

case. 1 No.

iii) Pressure gauge for oil pressure

tank. 1 No.

iv) Dial thermometer for turbine

bearing 1 No.

v) Dial thermometer for upper guide

bearing of generator 1 No.

vi) Dial thermometer for lower guide

bearing of generator. 1 No.

vii) Dial thermometer for thrust

bearing of generator. 1 No.




5.9 ASSEMBLY AND INSPECTION AT FACTORY.

1. Distributor assembly -in the presence

- Head cover, bottom ring, and of Purchaser’s

guide vanes regulating representative

mechanism (excluding runner

and shaft) shall be assembled

by using assembly stand and

following shall be checked.

Side and bedding face

clearances of guide vanes.

- Stroke of servomotor and its

relation to guide vane opening.- Match marking and doweling

shall be done.

2. Draft tube liner and cone Manufacturer’s

assembly and match marking -inspection

certificate

3. Runner and shaft assembly

and dowelling -----’’-------4. Pressure oil system comprising - in the presence

Sump tank air/oil accumulator, of Purchaser’s

actuator, servomotor and representatives

connected piping

5.10 TEST CERTIFICATE AND INSPECTION REPORTS:

LEGEND :

1) Composition and physical properties of the material in the

following components shall be supplied.

2) For welded joints. The welded joints of the following

assemblies/components shall be examined by ultrasonic and/or

radiographic methods




3) For hydraulic pressure test and leakage test.

4) Dimensional accuracy.

5) For surface finish.

Sr. No Particulars of Assembly 1 2 3 4 5

1 Runner - Runner rim, runner blades √ √ √

2 Shaft - Main shaft √ √ √

3 Spiral case, ring and stay vanes: Spiralcase, stay ring, Parallel plates, Stayvanes, Steel plates, draft tube liner,Support cone.

√ √ √

4 Head cover and regulating apparatus:

Head cover, Wearing rings (rotating),Facing plates, Coupling bolts, Bottomring.

√ √ √

5 Draft tube Liners √

6 Stay ring / spiral assembly √ √ √

7 Head Covers √

8 B.F. valve. √ √ √

9 Bottom ring and / discharge ring. √

10 Sump tanks air/oil accumulators,Servomotor/cylinders. √

11 Penstock and Specials. √

12 Oil sump tank. √

13 Oil pressure tank. √

14 Oil coolers. √

15 Guide vane servomotor cylinders. √

16 All the components of the turbine √

17 Runner vanes crown and blanksurfaces.

√

18 Stay ring upper & lower surfaces. √

19 Stay vanes. √

20 Guide vanes. √




21 Bearing pads. √

22 Head cover facing plates. √

5.11 TESTS ON SITE.

After completion of erection each of the sub system shall be individually

operated and tested to verify if the specified performance/functional

requirements are achieved.

The following are illustrative list.

i) Pressure oil system.

ii) Compressed air system.

iii) Cooling water system,

iv) Governing system according to IEC 308.

v) Dewatering and drainage system.

vi) B.F. valve.etc.

5.12 STANDARDS.

Turbine and governing system shall be designed, manufactured and

commissioned to the latest I.E.C standard accepted standard practices. A

few of the standards are listed below but not limited to.

IEC-41/1991 Field acceptance tests.

IEC- 545 Commissioning procedure.

IEC-607 Thermodynamic method measuring.

IEC-609 Cavitations pitting evaluation.

IEC-193/1965,193-A/1972

and 995/1991 Scale model testing.IEC-994/1991 Guide for field measurement.

ASME Tank and hydraulic cylinders.

IEC- 308 Governor testing.




ASME VIII,

ASME V

ASTMA 435

ASTMA 609, welding materials

ASTMA 709 .

ASTMA A 388 and

IEC 404

ASME Boiler and pressure vessel code section VIII, Dim 2 Low cycle

fatigue.

IEC- 34.9 Noise limits for electrical machines.ISO- 1996 Noise measuring.

VDI-2056 Vibration limit.




ANNEXURE V-1

LIST OF DRAWINGS, DESIGNS AND MANUALS TO BE SUBMITTED BY THESUPPLIER AFTER THE AWARD OF CONTRACT

Sr.

No.

Brief Description To be submitted

within monthsfrom the awardof contract

Remark

1 2 3 4I1

DRAWINGSGeneral plans and sections showing allessential details of turbine assembly,setting and water passages

3 For approval

2 Plans and cross sections of powerhouse showing layout of equipment

listed below, floor arrangement,principle dimensions and scope of works

- Penstock pipes to be provided at bothsides of the Inlet valve to connectpenstock and spiral casing.

- Inlet Valve.- Turbine components- Governing system- Pressure pumping systems for

governing

- Stay ring and spiral case- Draft tube and draft tube liner- Generator outline- Generator barrel- Speed signal device, excitation

equipment- Line and neutral end cubicles- Unit control board- All unit auxiliaries

- All station auxiliaries viz. coolingwater system,drainage& dewatering

system, compressed air systems. etc.

3 For approval

3. Cross Section through Turbine andlongitudinal section of turbine inmachine hall

3 For approval




4. Installation drawings of:- Draft tube liner, elbow and cone- Spiral case/stay ring assembly- Guide apparatus, regulation and

operating mechanism- Runner and housing- Shaft and shaft seal- Head cover, lower and upper coverings- Guide vanes and sealing- Turbine bearing, lubrication and

cooling- Test equipment for pressure testing of

spiral case- Turbine platform in Turbine pit.

666

66888

6

8

For approval

5. Governor, governing scheme and

connection diagram, hydromechanical and electrical cabinets

12 For approval

6. Control diagram for Turbine 8 For approval

7. Runner removal arrangement. 3 For approval

8. Schematic diagram for auto control of Turbine

8 For approval

9. Drawings of tools, tackles and erection

devices

3 For reference

10. Leaking piping 8 For reference

11. Embedment in:- DT liner and cone concreting- Stay ring and spiral case concreting

- Generator barrel concreting

366

For approvalFor approvalFor approval

12. Area velocity curve for draft tube 3 For reference

13. Layout plan and cross-sections showing

details of floor openings (for piping,cables etc.)

- Trenches- Block-outs/cut outs- Openings in concrete

8 For approval




ANNEXURE – V2

SCHEDULE OF INDICATING AND RECORDING INSTRUMENTS FOR TURBINE AND EQUIPMENT ASSOCIATED W

Number Provided Total Sr.No

.

Item Type of

instrument

deviceOn or near

the

equipmentor locally

At Generator-

gauge

panel

At Governor

Cabinet

At Unit

Control

Board

1 2 3 4 5 6 7 8

1 TEMPERATURE OF

i. Guide bearing segment

ii. Guide bearing oil 24 point

indicator

(Provided by

Gen-Motor

manufacturer)

- 1 - - 1

iii. Cooling water at

Outlet of guide

bearing

iv. Guide bearing segment. DTT - 1 - 1 2 v. Guide bearing Oil. DTT - 1 - - 1

vi. Cooling water at outlet of

guide bearing.

DTT - 1 - - 1

vii. Governor sump oil. DTT - 1 - - 1

2 PRESSURE AT

i. Inlet to Butterfly valve i.e.

penstock.

PG +RL 1 1 - - 2

ii. Draft Tube. PVG 1 - - - 1

iii. Inlet & outlet of cooling

water to the guide bearing.

PG+RL 2 - - - 2

iv. Guide vane servomotor. PG+RL 2 - - - 2

v. Governor oil pressure receiver PG+RL 1 1 - - 2

vi. Spiral pressure near Butterflyvalve PG+RL 1 1 - - 2




1 2 3 4 5 6 7 8

vii. BFV oil Pressure PG+RL 1 - - - 1

3 LEVELS OF.

i. Oil in governor sump tank Sight gauge + relay 1 - - - 1

ii. Oil in Air/Oil pressure

receiver

-do- 2 - - - 2

iii. Oil in leakage oil tank -do- 1 - - - 1iv. Oil in guide bearing reservoir -do- 1 - - - 1

4 FLOW OF.

i. Cooling water inlet to guide

bearing

Flow indicator 1 - - - 1

ii. Cooling water inlet to shaft

seal.

-do- 1 - - - 1

Iii Discharge through spiral case

.

- do- - 1 -- - 1

5. STATUS INDICATION FOR

i. Governor Oil

pump No.1

running/standstill/fault

Lamp Set - - Se

ii. Governor Oil

pump No.2 running/standstill

-do- Set - - Se

iii. Leakage Oil pump for

governor running/standstill/fault

-do- Set - - - Se

iv. Head cover drain pump

running/standstill/fault

-do- Set - - - Se

v. Guide vane remained open

after close

-do- - - - 1 1




1 2 3 4 5 6 7 9

vi. Guide vane lock in/out -do- - - - 2 2

vii. Dome light -do- 1 - - - 1

ix. Main inlet Butterfly valve

open/transit/close

-do- Set - - Set Set

6 OTHER ITEMS

i. Setting of guide vane limiterand gate position

Gate limiter andgate position

indicator

- 1 1 1 2

ii. Turbine speed Tachometer - - 1 1 2

iii. Governor speed droop setting -do- - - 1 - 1

iv. Governor balance meter

indication

Governor

balance meter

- - 1 1 2

v. Wearing of shaft seal

detection

Water detector 1 - - - 1

vi. Water in guide bearing Oil

reservoir

Water detector 1 - - - 1 set

vii. Ammeter with panel switch

for each motor

Ammeter 1 set - - - 1 set

viii. Voltage with selector switch

for each 415 volts bus bar.

Voltmeter 1 set - - - 1 set

ADDITIONAL INDICATING AND RECORDING INSTRUMENTS

(To be recommended by Supplier)




ABBREVIATIONS :

RTD means Resistance temperature detector

DTT means Dial type thermometerPG means Pressure gauge

PVG means Pressure/Vacuum gauge

BFV means Butterfly Valve

PG+RL means pressure gauge and guard relay

NOTE:

1 Dial type thermometer and relays shall be used for alarm annunciation/shut

down also.

2. Turbine and generator supplier shall co-ordinate in joint use of

indicators/recorders, wherever possible.

3. Supplier shall indicate changes if any required in number, type and

location of instruments.

4. Information will also be fed to microprocessor based control system

covered under scope of supply of generator supplier. (Information such as

bearing temperatures, cooling water parameters, water pressure, draft tube

pressure, spiral pressure. Governing system parameter, servo strokes,

guide vane opening and limit, inlet valve parameters, compressed air

system details) For this purpose necessary tapping points shall be

provided by turbine supplier in consultation with generator supplier.




ANNEXURE V3

SCHEDULE OF CONTROL FOR TURBINE AND I TS ASSOCIATED

EQUIPMENT

Sr.

No

Description Type of

device

Number Provided Total emark

Locally

or in

the

vic in i ty

At

enera tor

gauge

panel

At

Governor

Cabinet

At

Unit

Control

Board

1. 2. 3. 4. 5. 6. 7. 8. 9.

1

2.

3.

4.

Guide vane

limit control

Auto / manual

Selection for

Governor

operation

Selection of

location of

governor

control (local/

remote)

Speed load

control

Raise /

Lower

switch

Selector

switch

-do-

Raise /

Lower

Switch

-

-

-

-

-

-

-

-

1

1

1

1

1

-

1

2

1

1

2




5.

6.

7.

8

9

10

11

Speed droop

Control

Turbine

Guide vanes

Locking

Emergency

Turbine shut-

down

Governor Oil

pump No.1

starting/

stopping.

Governor Oil

Pump No. 2

Starting/

Stopping

Main /

standby

Selection of

governor oil

pump

Auto / manual

mode selector

of governor oil

Control

Switch

Locking

device

Push

button

-do-

-do-

Selector

Switch

-do-

-

1

-

2

2

1

1

-

-

-

-

-

-

-

1

-

1

-

-

-

-

-

-

1

2

2

-

-

1

1

2

4

4

1

1




12

13

14

15

16

17

18

pump No 1

Auto / manual

Selector for

Governor oil

pump No. 2

Local / remote

Mode

selection for

governor oil

pumps.

Control of oil

leakage pump

Auto / manual

Selection for

oil leakage

pump

Headcover

pump starting /

stopping

Unit starting /

stopping

Butterfly

valve ON/

OFF (Closing

/ Opening)

-do-

-do-

Push

button

Selector

switch

Push

button

Control

switch

Push

button

1

1

2

1

2

-

1

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

1

1

1

1

2

1

2

1

2




ADDITIONAL CONTROLS

(TO BE RECOMMENDED BY SUPPLIER)

NOTE : 1. The items quantities and locations of controldevices tentatively indicated. The supplier shall

indicate changes if any.




4.

5.

6.

7.

ii. Oil in governor Oil sump

tank low

iii. Oil in governor air/oil

pressure receiver

iv. Oil in BFV air/oil

receiver

HIGH LEVEL OF

i. Oil in oil leakage unit

ii. Water in Turbine head

cover

LOW PRESSURE IN

I. Governor air/oil pressure

receiver

ii. Governor air/oil pressure

receiver very low

HIGH PRESSURE OF

I. Oil in governor oilpressure receiver

FAILURE OF

i Shear pin

ii.Speed sensing system

iii. Power supply to unit

control board

iv. Supply to governor

cubicle

-do-

-do-

-do-

Level

relay

Float

Pressure

switch

-do-

Pressureswitch

Limit

Switch

-Voltage

relay

-do-

-do-

1

1

1

1

1

1

1

1

Set

1

1

1

-

-

-

-

-

-

-

-

-

A

A

A

AS

A+AS

A+AS

A

A

A

AS

A

A

A

AS

AS




8.

9

10

Unit over speed detection

Water in guide bearing oil

detection.

Emergencies

Speed

relay

Water

detection

Emergency

shutdown

switch

1

1

1

A

-

AS

As

A

AS




ADDITIONAL SAFETY DEVICES

(TO BE RECOMMENDED BY SUPPLIER)

ABBRIVATION:DTT means dial thermometer.

A means alarm annunciation

AS means shut down and annunciation

A+AS means two stages for alarm and shut down

NOTE : 1. Items, quantities and locations of devices are

indicated and supplier shall indicate changes if

any.




INDICATION, CONTROL AND SAFETY DEVICES FOR AUXILIARY EQUIPM

Number Provided/Annunciation Total Sr.

No.

Item Type of

instrumentdevice

On or nearthe

equipment

locally

At Auxiliarygenerator

Motor

Control

Board

AtGovernor

Cabinet

At UnitControl

Board

1 2 3 4 5 6 7 8

A INDICATION/RECORDI

NG

1. Air compressors for

Brakes standstill/ running

Indication Lot Lot

2. Drainage & Dewatering

and pumps Standstill

Running Main 1, Main 2

Lamp Lot Lot

3. Cooling water pressure

(High/Low)

Indication Lot Lot

4. Pressure in Air receiver

for Brakes

(pressure

Gauge+RL)

4 4

5. Pressure in air/oil

receiver for Governor

(pressure

Gauge+RL)

4 4

6. Ammeter with selector

switch

Lot Lot Lot

7. Current and voltage

meter for three phase

indicationsVoltmeter withselector switch for each

415 V motor

Lot Lot Lot




DEPARTURE FROM SPECIFICATION

( To be filled by the Bidder.)

I tem Description of departure Reference to Clause in the specif ication




DATA SHEETS

DATA SHEETS OF TURBINE

1) Name of the Manufacturer :-………………………….

2) Type :-………………………….

3) Guaranteed rated capacity (output)

at a rated net head of 106 m :-……………………. KW

4) A) Full gate output at a net

head of

i) 117.0 m (max) :-………………………KW

ii) 84.0 m (min) :-………………………KW

iii) 106.0 m (Rated) :-………………………KW

B) Corresponding Discharge

For 4A) Above

i) 117.0 m (max) :…………………… m3 /sec

ii) 84.0 m (min) :-………………… m3 /sec

iii) 106.0 m (Rated) :-…………………. m3 /sec

C) Guide vane opening

Corresponding to rated

Net Head of 106m at

i) 100 % output :---------------------- %

ii) 75 % output :-…………………. %

iii) 50 % output :-……………………%

Guide vane opening corresponding to 110 % output shall be 100 %

D) Head at 110% Output :-……………………m

E) Discharge at 110% output :-………………… m3 /sec




14 Flywheel effect

a) of the generating unit for

regulation stated in item (10) & :-………………tm2

(12) above.

b) of turbine runner & shaft :-……………… tm2

15 Maximum gross head on turbine

(inclusive of water hammer) at

the time of gate closure in (10)

above.

16 Runner

a) Material

i) Cone :-……………..

ii) Blades :-…………….

b) Material of wearing ring :-…………………

c) No. of blades :-……………………

d) Weight :-…………………

e)Inlet dia. :-…………………

f) Velocity of water :-…………….m/sec.

( Full gate, 106 m Net head)

17 Shaft

a) Material :-………………….

b) Weight :-………………Kg.

c)Diameter/bore :-………….mm/mm

d)Length :-……………mm

e)Material of sleeves :-…………..




f)Method of removing and

attaching the sleeves. :-……………..

18 TURBIN E GUIDE BEARIN G

1) Type of guide bearing :-………………

[adjustable segmental type

self lubricated bearing]

2) Diameter of turbine

guide bearing : . . . . . . . . . . . .. . .mm

3) Radial clearance of turbine

guide bearing :-. . . . . . . . . . . .. .mm

4) Number of segments :-. . . . . …….

5) Total effective surface of

all segments :- ….... . . . . .m2

6) Circumferential length

of segments :-…….…...mm

7) Axial length of segments :- …. ……mm

8) Dynamic viscosity of oil :-………...m/s2

9) Maximum temperature for

-oil film :……. .. . . . . . . .oC

-segment (≤ 70oC ( r) ) : . . . . . . . . . . .. . . .

oC




10)Total flexibility of turbine

guide bearing

[not more than:≤0.4mm/MN(d)] :-………..mm/MN

11) Quantity of lubricated oil reservoir :-. . . . . ……..m3

12) Quantity of cooling water :-…….... . . . 1/s

13) Total losses in guide bearing

at rated load :…….... . . . .kW

14)Permissible duration of operation

of the unit at rated load without

supply of cooling water. : . . . . . . . . . . . .minutes

19 Head Cover

a) Material and construction :-………………..

b) Weight :-…………………

c) Rating of AC pump motor for :-……………….prevention of accumulation

of water

d) Rating of DC pump motor for :-…………………

prevention of accumulation

of water

e) Method of ensuring water :-…………………..

tightness at shaft entry and

description of the arrangement

proposed.




20 Discharge Ring

a) Material and construction :-………………….

b) Method of connection to the :-…………………..

stay ring.

21 Guide Apparatus

a) Material and construction of

wicket gates :-……………………

b) No. of wicket gates :-……………….

c) Height of wicket gates :-………………

d) Material of wearing plates :-……………….

above and below vanes

e) Material of guide vanes :-…………………..

bearing (stainless steel)

( lubrication bearings DEVAtype (d) ]

f) Leakage through full closed :-……………………

gates under maximum static

head

g) Torque on turbine due to

the above leakage.

22 SPIRAL CASE AND STAY VANES

A) Spiral case

a) Type (constant velocity, :-……………………

acceleration etc.)




b) Material and Construction :-………………….

c) Thickness

i) maximum :-……………….mm

ii) minimum :-………………mm

d) Weight :-………………kg

e) Elevation of centre line of

distributor :-………………m

f) Max. velocity of water for full load

at rated head at outlet pipe from MIV :-……………m/sec

g) Velocity of water for full load at

rated head.

i) at inlet to spiral case :-……………m/sec

ii)at 900

from inlet :-…………..m/sec

iii) at 1800

from inlet :-……………m/sec

iv) at 2700from inlet :-……………m/sec

h) Method of erecting and

Concreting the spiral case

B) Stay ring

i) Material and construction of

Stay ring :-………………

ii) Number of vanes :-…………………




iii) Weight :-……………….kg

23 Turbine pit liner

a) Material and construction :-……………….

b) Height (approx) :-……………… mm

c) Diameter :-………………mm

d) Weight :-……………….kg

24 Draft Tube

a) Elevation of the lowest point

in draft tube :-……………….m

b) Distance from the C.L. of the

unit to the draft tube exit. :-……………….m

c) Velocity at draft tube exit :-……………m/sec

d) Extent of the draft tube covered

with a steel liner from unit centre :-……………….mm

line.

e) Thickness of the steel liner :-…………….mm

f) Weight of the steel liner :-……………….kg

25) PENSTOCK:-

a) Taper piece between penstock and MIV

i) Inlet diameter :-……………..mm




27 Governor

a) Rating :-………………….

b) Guaranteed sensitivity

(Min. speed change to which

governor will respond)

c) Range of adjustment of speed

droop characteristic

d) Stable operation guaranteed

for a min speed droop of :-……………….%

e) Guaranteed range of speed

level setting for which governor

will control the turbine effectively :-………………

f) Range of adjustment of gate

closing time :-……………….

g) Range of adjustment of gate

opening time :-……………….

h) Type of Governor :-…………………

i) Minimum turbine speed at

which governor operation will

start :-………………….

28 Max safe oil pressure for the

governor oil system :-…………. kg/cm2




29 Max. velocity of oil in pipe

parts of actuators and

servomotors of inter connection :-……………m/sec

pipes.

30 Oil pressure system

a) main oil pump

i) Type of pump :-……………….

ii) Capacity of pump (LPM) :-………………

iii) Rating of pump motor

KW :-……………….

rpm :-………………..

b) Stand by oil pump

i) Type of pump :-……………….

ii) Capacity of pump (LPM) :-………………


KW :-……………….

rpm :-………………..

c) Quantity of oil in one filling :-………………..

:-

d) Max. rate of oil consumption

from pressure tank :-……………..

e) Capacity of sump tank :-………………….

f) Total capacity of pressure tank :-…………………..

g) Number of complete operations

which can be performed by the

amount of oil in the pressure tank




with oil pump not work :-……………………

31 LUBRICANTS

a) Specification of oil :-……………………

b) Specification of other

lubrications :-……………………

32 Weight of turbine rotating parts :-…………………

33 Max. hydraulic thrust :-………………..

34 Heavies package for shipment

a) Name :-……………………

b) Weight :-………………….

c) Dimensions (L x B x L) :-……………………

35 Largest package for shipment

a) Name :-……………………

b) Weight :-…………………

c) Dimensions (L x B x H) :-…………………

36 Heaviest assembly to be lifted by

crane

a) Name :-………………

b) Weight :-………………

c) Dimensions (L x B x H) :-………………




41 Longest assembly to be lifted

by crane

a) Name :-………………

b) Dimensions (L x B x H) :-…………….

c) Max . Length :-……………….



Signature of Bidder Signature of Pur162

ANNEXURE -V-5

GUARANTEED AND OTHER TECHNICAL DATA FOR TURBI

Sr.

No.

Maximumcontinuous

power P max at

100% guide vane

opening.

100 %

output

power

75 %

output

power

60%

output

power

50%

outpu

powe

1 For max. net head of 117m

a) Turbine output power (KW)

b) Discharge (m3 /s)

c) Percentage guide vane opening 100%

2 For Rated net head of 106 m



c) Percentage guide vane opening 100 %

3 For min. net head of 84 m



c) Percentage guide vane opening 100%




Section VI

TECHNICAL SPECIFICATION OF MAIN INLET VALVES

INDEX

Sr. No. Description Page No.

6.1 General. 165

6.2 Design requirements. 165

6.3 Design specifications and performance. 166

6.4 Construction. 167

6.5 Valve operating mechanism. 171

6.6 Oil pressure supply system for Inlet valve. 172

6.7 Pressure system oil. 174

6.8 Accessories. 174

6.9 Hydraulic pressure test at site. 175

6.10 Tools and Equipment 175

6.11 Drawings, designs and manuals to be 175

submitted after award of contract.

6.12 Inspection and tests. 175

6.13 Miscellaneous. 178

6.14 Spares. 178

ANNEXURES

Annexure VI-1 179

List of drawings, designs and manuals to be submitted by

the supplier after award of contract.

Annexure VI-2 181

Departure from specifications.

Data Sheets 182




SECTION VI

MAIN INLET VALVE

6.1 GENERAL

The Inlet valve shall be butterfly type. Any fittings, accessories of

apparatus which may not have been specifically mentioned in these

specifications but which are indispensable for reliable operation of the

plant shall be provided by the supplier at no extra cost to the purchaser.

6.2 DESIGN REQUIREMENTS

BASIC DESIGN DATA

i) Number of inlet valves : One

ii) Purpose. : Turbine guard valve.

iii) Nominal diameter of inlet valve : 2000 mm Diameter

iv) Test pressure. : 24 kg/cm2

v) Operation.

Opening : by oil pressurevi) Closing time of Inlet valve:

-at still water : 90 sec.

-at rated discharge : 40 sec.

-under breakdown discharge : 30 sec.

vii) Opening time (including time

required to open by pass valve) : ≤ 90 sec.

viii) By pass valve : Oil pressure operated.

ix) Inlet valve shall have its own pressure oil system with air/oil

accumulator.

x) The Inlet valve and its control system shall be suitable for

frequent opening and closing . The minimum opening and

closing operations per day shall be five each.




6.3 DESIGN SPECIFICATIONS AND PERFORMANCE.

The Inlet valve shall be free from vibration or other abnormality under

steady-state operating conditions and under any possible transient

conditions and shall have sufficient strength and rigidity against

maximum transient water pressure.

6.3.1. REQUIRED SERVICE CONDITIONS

It shall always be possible to close the Inlet valve safely, without

vibrations or pressure surges, particularly

1) In normal service conditions with turbine guide vanes closed i.e.

without significant water flow and with pressure almost equal on

both sides.

2) In case of emergency with turbine guide vanes fully open i.e.

with rated discharge and with full pressure on one side of the

closing element near the end of closure.

3) In case of an accidental rupture of the pipe between the Inlet

valve and the turbine inlet (i.e. with the breakdown discharge and

the whole pressure on one side already at the beginning of closure.)

6.3.2. GUARANTEES

Guarantees for Inlet valves must be given by the Bidders for:

1) Low level of vibration and noise during closing.

2) Strong construction and adequate design of housing.

3) Proved design of rotating parts.

4) High level of water sealing.

5) Minimum losses in the opened position.




6.3.3. CONTROL

Control of Inlet valve shall be hydraulically by means of its own oil

pressure unit.

The opening shall be performed by an oil pressure unit discharging into

the valves opening cylinders. Closing of the valve shall be by closing

weights and the discs hydraulic self closing tendency with closing

cylinders acting as brake.

Following modes of control shall be provided.

- Manual local from the respective control cabinet near Inlet valve

location.

- Automatic operation from the unit control board and from

computer system as a part of automatic control sequence of

Turbine Generating Unit.

6.3.4. DISCHARGE SHUTDOWN PERFORMANCE

Inlet valve shall be capable of shutting down rated discharge of turbine

at all heads safely and reliably under unbalanced conditions. Also Inlet

valve shall be capable of closing during emergency conditions, safely

and completely against full unbalanced flow occurring as a result of

breakdown of guide vanes and/or expansion joint or downstream air

valve.

6.3.5 AMOUNT OF WATER LEAKAGE.

Amount of water leakage past downstream side seal shall be less than

0.5 litre per minute at the maximum static pressure of 138. m.w.c.

6.4 CONSTRUCTION.

6.4.1 VALVE BODY

Valve body shall be made of welded carbon steel plates. Valve

body shall be suitably minimum divided if necessary considering




transportation and shall be connected by flange at site. Valve

body shall be of sufficiently stiff structure to withstand the

maximum water pressure to cause no detrimental deformation

even against the constant maximum hydrostatic design pressure.

Valve disc shall be provided with valve trunnion of forged steel

at both ends and each trunnion with a stainless steel bushing or

stainless steel welding overlay at the sealing and bearing

portions. Valve trunnion shall be designed to be safe under

maximum pressure and shall smoothly move in the bearing.

Valve trunnion shall have sufficient diameter and shall not cause

excessive deflection. Trunnion bearing shall be self-lubricating

with bronze backing and with Teflon fabric liner.

Trunnion bearing seals shall be on both ends of each bearing and

shall be made of self lubricating PTFE compound with integrated

Rubber-o-ring.

Bearings shall be capable of safely supporting the weight of the

valve disc and force caused by water pressure and shall be

capable of operating the valve smoothly.

Water operated, movable stainless steel seal, seal rings shall be

provided at both the upstream and downstream sides.

Wearing surfaces adjacent to seal rings shall be lined with

corrosion resistant material.

6.4.2 SERVICE SEAL AND MAINTENANCE SEAL

- The inlet valve shall be supplied with a service seal and

maintenance seal.

- The service seal shall be located on the downstream side

of the valve with a flexible rubber (or other adequate

better material) and shall not be split. It shall be

adjustable and repairable. The service seal in the valve




casing shall be of corrosion and erosion resistant material

(for example stainless steel service seal)

- The maintenance seal shall be located on the upstream

side of the valve. It shall allow maintaining, repairing or

replacing the valve in situ with the upstream waterways

fully pressurised. The design of this seal shall ensure

required tightness in closed valve position and shall not

tend to flutter under any possible hydraulic conditions in

the pressure shaft. The complete material and sequence of

replacing the service seal shall be furnished by the bidder

in his bid comprising explanatory write ups, sketches and

drawings.

6.4.3 VALVE DISC

Valve disc shall be of lattice (biplane) type made of steel plates

and shall have sufficient strength against all operating conditions

so that no detrimental deformation is caused. Besides, valve disc

shall not cause any abnormal vibration during full opening and

closing operation or transit fluttering and shall not cause muchwater leakage.

Valve disc shall be provided with valve trunnions of forged steel

at both ends and with seal ring made of carbon steel overlaid by

stainless steel at the sealing portions. Valve trunnions shall be

designed to be safe under the maximum dynamic pressure and

shall smoothly move in the bearing. Valve trunnions shall have

sufficient diameter and shall not cause excessive deflection.

Valve disc shall be welded steel structure or cast structure but

shall not be lens type.

Arrangements for removal of air trapped in the pressure shaft

shall be made and shall remain operative during operations.




6.4.4. PRESSURE BALANCING BY PASS VALVE

A needle type by pass valve of adequate size (i.e. dimension)

shall be provided keeping in view the requirement of overall

opening time in the turbine mode. The valve shall be operated by

means of pressure oil system provided for the valve operation.

The sealing of by pass valve shall be leak proof and its operation

shall be by oil pressure of the governor oil pressure unit.

The by-pass valve shall not cause pitting by cavitations and

excessive vibration and noise during operation. It shall operate

reliably and shall be capable of safely preventing water leakage

when closed. By pass valve shall be fitted with an oil operated

needle valve fitted with a hand operated geared guard valve.

6.4.5. AIR VALVES

Suitable capacity air admission valve shall be provided on down

stream side of valve to protect spiral case and shall also act as air

exhaust valve during pressuring of spiral case. However leakage

of water shall not occur during operating conditions. Suitable air

valve shall also be provided on the upstream of inlet valve to

protect pressure shaft.

6.4.6. CONNECTING PIPE

A) the penstock. The connecting pipe shall be made of samematerial as penstock (ASTM 517 Gr. F or equivalent) and shall

be provided up to 12000 mm from the centre of Turbine towards

the penstock with 300 mm allowance, and shall have inner

diameter of 2000 mm and shall withstand the maximum water

pressure caused by Turbine operation. The inlet valve and




connecting pipe shall be connected by rigid flanges and

connecting bolts and nuts and packing shall be supplied.

The connecting pipe shall be equipped with a complete set of

pipes, valves etc. required for dewatering of penstock.

B) Connecting pipe shall be provided between the inlet valve and

the spiral. The connecting pipe shall be made of same material as

penstock (ASTM 517 Gr. F or equivalent).

The connecting pipe shall be equipped with a complete set of

pipes, valves etc. required for dewatering of spiral.

6.5 VALVE OPERATING MECHANISM

Valve operating mechanism shall comprise of the servomotor, operating

rod, lever-closing weight etc. During closing, the servomotor shall act

as a brake. The servomotor shall be of balancing type and heavy

supporting plates with anchor bars, fastenings etc. shall be provided to

mount it on its foundation block.

Main parts of the operating mechanism such as servomotor, rod, lever

and connecting part with the valve trunnions shall have strength and

capacity sufficient for safely and reliably shutting down againstmaximum discharge and opening full flow discharge under all operating

conditions of plant without causing any excessive vibration and other

abnormality. Dimensions of rods shall be so as to transmit all

operational forces without deflections all pivots shall be preferably of

the self-lubricated type. The closing weight shall be of cast iron and fast

securely to their levers.

Operating mechanism shall be provided with a locking device for

manually locking of both the main valve and by-pass valve when they

are closed.

Operating mechanism for the valve including the piping and valves shall

safely and reliably operate during the service for a long period of time.

Parts which come in contact with water shall be made of stainless steel.




Limit switches for open / close, transmitters, contacts etc. for local and

remote operation and indication of valves shall also be provided.

6.6 OIL PRESSURE SUPPLY SYSTEM FOR INLET VALVE

6.6.1 PURPOSE

Oil pressure supply system shall be used for operation of the inlet valve,

by pass valve and operation control devices for the valve.

6.6.2 SYSTEM

Each system shall comprise the following:

- One sump tank located adjacent to inlet valve and dimensioned

for 120% of the combined oil volume in the servomotor in fully

open position, oil piping and valves and pumps. The tanks shall

be provided with a filling opening (with strainer and cover),

breather, breather openings, sight oil level gauge with cocks,

drain with cock and one man hole for inspection, dial type oil

level gauge and oil level relays for oil level low / high warning.

- Two screw type silent running and self-priming oil pumping unitseach with suction strainer and capable for continuous operations.

The pumps shall be vertical type coupled directly with their

moisture and dust proof alternating current 400V electric

induction motors. Both pumping units shall be identical and

equipped with complete control system permitting the selection

of either unit acting as stand-by and starting automatically as

when other pumping unit fails.

- One small pressure oil accumulator in parallel arrangement

between the oil pump and servomotors and located in the cabinet

of pressure oil unit. This accumulator shall act as a buffer and oil

pressure holding means to prevent the oil pump from too frequent

starting.




- One hand operated double acting oil pump mounted in the sump

tank.

- The control valves for the inlet valve drive.

- All valves such as safety valve, non-return valve etc.

- All oil piping and shut off valves within the oil sump tank and

between the oil pumping set and servomotors.

Control cabinet containing following instruments and switches.

- Two pressure gauges for indication of upstream and downstream

water pressures of inlet valve along with recording facilities.

- One pressure gauge for indication of oil pressure with contacts.

- One selector switch for local, manual, remote control of inlet

valve.

- Control switches of pumps.

- One pump selector switch.

- Three push button switches for opening, stopping and closing of

butterfly valve.

- One switch with ‘ON’ and ‘OFF’ position for testing of oil

pumping unit.

- One electric heating element.- All necessary relays, fuses, signal LED lamps, terminal blocks

and other equipment for a complete and safe local and remote

control of the inlet valve.

- The cabinet shall be of self-standing sheet metal type, moisture,

vapour, vermin and dust proof with lockable front door. All

wiring shall be run in the most efficient manner from point to

point. There shall be no jointing or teeing of wires between

terminals. All control cabling between individual devices,

instruments, switches etc. up to control cabinet of inlet valve

shall be provided.

Control of pumps shall also be possible from the unit control

board located in the Control Room.




Pressure switches shall regulate on off control operation of

pressure oil pumps. When the normal oil pumps fails, the stand-

by pump shall start automatically.

Change over between the normal operation and stand-by pump

will be carried out through the changeover switch provided on

the control cabinet.

Besides, starting and stopping shall be carried out not only

automatically and remotely but also manually from control

cabinet.

6.7 PRESSURE SYSTEM OIL

First filling plus 25% extra quantity of pressure system oil, required for

inlet valve and its pressure oil system shall be supplied by the supplier.

Supplier shall suggest the oil equivalent available in India for future

maintenance and operation of the plant.

6.8 ACCESSORIES

Following shall be supplied but shall not be limited to

- All necessary sole plates, foundation bolts, anchors etc. for inletvalve and servomotor.

- All platforms, ladders, stairs, handrails, plate coverings, hooks,

pulley blocks etc. necessary for obtaining easy and safe access

to parts and item which are fitted with equipment. The name

plates showing makers name, serial number, year of manufacture,

type, rating, capacity etc. for valve assembly and servomotor

shall be provided.

- All necessary washers, bolts, nuts etc. of high quality steel.

- All necessary turn buckles and pipe jacks needed for erection,

operation and maintenance.




6.9 HYDRAULIC PRESSURE TEST AT SITE

If the transport limitations permit, the inlet valve shall be despatched in

one piece duly assembled and pressure tested in workshop. In case, it is

not possible to transport assembled valve to project site, it shall be

pressure tested again at site (upto 1.5 times of design pressure for a

period of not less than 60 minutes) after its erection. To carry out this

pressure testing at site the supplier shall provide one set of bulkheads

common to the two inlet valves and all necessary pickings and jointing

material and testing equipment.

6.10 TOOLS AND EQUIPMENT

One sets of ordinary and special spanners, wrenches, special tools,

slings, ropes etc. for the proper erection and maintenance of the inlet

valve shall be supplied.

One set of spanners and standard tools and equipment. Each set shall be

supplied with a sheet metal lockable toolbox, fitted internally so that the

tools may be stored in an orderly manner.

The heavy tools and equipment shall be marked as to size and purpose.

6.11 DRAWINGS, DESIGNS AND MANUALS TO BE SUBMITTED

AFTER AWARD OF CONTRACT

These shall be submitted as per the list given in Annexure-VI-1 of this

section. Mode of submission of drawings, designs will be intimated to

the successful bidder in due course.

6.12. INSPECTION AND TESTS

Inspection and tests at factory shall be carried out by the supplier as per

list given below:

LEGEND

1. Material analysis.

2. Tensile test.




3. Notch impact test.

4. Bending test.

5. Visual inspection.

6. Magnetic particle examination.

7. Liquid penetration examination.

8. Ultrasonic test.

9. Radiographic test.

10. Pressure test.

11. Leakage test.

12. Dimensional check.

13. Erection check.

14. Welding procedure approved by purchaser.

15. Corrosion protection.

Suffix – A :- Test at workshop in the presence of Purchaser.

SUBMISSION OF TEST CERTIFICATES :-

The supplier shall submit six (6) copies of test certificates to the

purchaser as per the procedure given below :

For inspection and testing specified to be done in presence of PurchaseTest certificates shall be submitted for approval.

For all other inspection and testing test certificates showing that the

specified tests/inspection has been carried out successfully by the

supplier, shall be submitted for reference.

Following assembles will be inspected




Sr.No. Particulars of

Assembly

1 2 3 4 5 6 7 8 9 10 11 12 13 1

4

1

5

1. Bipartition flanges

2. Connection

flanges

3. Bearing hubs.

4. Cylinder Shell

5. Valve body

6. Disc trunnions.

7. Disc plates.

8. Valve disc.

9. Assembled valve,

seat, body and

disc.

10.Operating

mechanism

a.Cylinder flanges

b.Cylinder shell

c.Welded cylinder

d. Cylinder covers

e. Piston rod.

f. Piston rod heads

g. Assembled

operating

mechanism.

11. Operating

mechanical lever

hub.

12. Auxiliary valve.

a. By-Pass valve.

b. Air valve.

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√

√7

A

√7

A

√

√

√

√

√8A

√

√

√8A

√

√

√8A

√

√ √

√

√

√

9A

√

10A

√10

A

√

√

√

11A

√11

A

12A

12A

√12

A

√

√

√

13A

√

√ √




13. Upstream pipe

a. Connecting

flange.

b. Cylinder Shell.

c. Welded pipe.

14. Downstream

pipe.

a. Flange rings.

b. Cylinder shell

c. Welded pipe.

√

√

√

√

√

√ √

√

√ √

√

√8A

√

√

√8A

√

√10

A

√11

A

√12

A

√ √

6.13. MISCELLANEOUS

Relevant provisions wherever applicable needed for indicating, recording

instruments, control switches, safety devices, gauges, flow meters, etc. for

normal operations and field test shall be made by valve supplier in consultation

with turbine supplier and facilities needed by supplier of control and protection

system.

6.14. SPARES

Spares shall be supplied as per Section-III of this volume.




ANNEXURE VI - 1

List of drawings, designs and manuals to be submitted by the supplier after the

award of contract.

Sr.

No.

Brief Description Within months

From the date of Notification of award of

Contract

Remark

1 2 3 4

1.

2.

3.

4.

5.

6.

7.

8.

9

10

11

12

13

14

DRAWINGS

i) Arrangement of Inlet valve

ii) Installation of Inlet valve

Valve servomotor

Tools, tackles and erection devices of Inlet

valve

Arrangement of Inlet valve piping

Outlet pipe with dismantling joint

Control gear diagram for Inlet valve

Arrangement of air valve

Foundation of valve and servomotor and

loading on foundations, under worst

operating and earthquake conditions

Arrangement of operating mechanism

Sealing arrangement

Pressure oil system with piping

Compressed air system piping

Layout with section of trenches, block outs

etc. for piping & cables

Interconnection and wiring diagram and

cable schedule

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

For reference

For approval

For reference

For reference

For approval

For approval

For approval

For reference

For approval

For approval

For approval

For approval

For approval

For approval

For approval




1

2

3

4

DATA

Opening and closing characteristics.

Max. Efforts and Max. Toque on foundation

and steel shaft.

Consideration made in data about loading

on foundation of main inlet valve and

servomotors.

Adequacy of oil supply system.

3

3

3

3

For approval

For approval

For approval

For approval

1.

2

3.

4.

5.

MANUALS

Manuals for storage, preservation and

handling of the supplied goods

Manual for erection/ dismantling testing and

commissioning of the supplied goods

Maintenance manual

Tolerance for assembly

List of consumables, oils & Spares

12

12

20

12

12

For reference

For reference

For reference

For reference

For reference




DATA SHEETS

1 Type :- ……………………..

2 Nominal diameter :- …………………….. mm

3 Material of valve :- ……………………..

4 Material of valve disc :- ……………………..

5 Design pressure :- …………………….. Kg/cm2

6 Test pressure :- …………………….. Kg/cm2

7 Factor of safety over yield point :- ……………………..

8 Time of opening :- …………………….. Sec.

9 Time of closing during

Normal operation :- …………………….. Sec.

During emergency :- …………………….. Sec.

10 Leakage through closed valve :- …………………….. Ltr/Sec.

11 Method of opening :- ……………………..

12 Method of closing :- ……………………..

13 No. of Servomotor :- ……………………..

14 Whether maintenance seal is provided :- ……………………..

15 Location of maintenance seal :- ……………………..

16 Weight of valve :- …………………….. Kg

17 Weight of heaviest part to be transported :- …………………….. Kg

18 Dimension of largest part to be transported

(Lx BxH)

:- ……………………..

19 Oil pressure system :- ……………………..

a) Main oil pump

i) Type of pump :- ……………………..

ii) Capacity of pump :- …………………….. LPM


KW :- ……………………..

rpm :- ……………………..




SECTION – VII

TECHNICAL SPECIFICATIONS OF STATION

AUXILIARIES




SECTION VII

TECHNICAL SPECIFICATIONS OF STATION AUXILIARIES.

INDEX

Sr. No.. Description Page no.

7.1 General. 186

7.2 Schedule of Requirements. 186

7.3 Compressed Air System. 188

7.4 Drainage and Dewatering System. 191

7.5 Cooling Water System. 195

7.6 Standards. 199

7.7 Inspection and Tests. 200

7.8 Drawing and Data To Be submitted 201

with Bid.

7.9 Drawings, Designs and Manuals to be 201

furnished after Award of Contract.

7.10 Spares. 201

ANNEXURES.

Annexure - VII-1 202

List of Drawings, Designs and Manuals to

be submitted by the supplier after award of

contract.

Annexure - VII-2 205

Departure from specifications.

Data Sheets 206




SECTION VII

TECHNICAL SPECIFICATIONS OF STATION AUXILIARIES.

7.1 GENERAL.

This section covers the technical specification and requirement of the

station auxiliary system/equipments.

Any fittings, accessories of apparatus which may not have been

specifically mentioned in these specifications but which are

indispensable for reliable operation of the plant shall be provided by

supplier at no extra cost to the purchaser.

The capacities and ratings mentioned for various auxiliaries in the

scheme shall be rechecked by the supplier and these shall be subject to

approval by the purchaser.

Relevant provisions of section No.I shall be applicable.

7.2 SCHEDULE OF REQUIREMENTS.

7.2.1 COMPRESSED AIR SYSTEM.

1) Compressed air system shall consist of following :-.

2 Nos. of compressors :- (one main and one 100% stand-by) to

cater the compressed air requirement of Generator brakes,

Governor OPU, shaft seal etc. .(one main and one 100% stand-

by).

Air Receivers:

1 No. of adequate capacity Air Receiver located at suitable

location.




Piping and Valves:

All pipes, valves required for the entire compressor system and to

lead the compressed air to individual equipment with pressure

gauges, pressure switches etc.

2) Motor Control Centre:

For the compressors mentioned above, motor control centre to be

located near compressor shall be provided.

3) Cabling:

All power and control cabling between the motor control centre

to compressor motor sets and all devices such as pressure

switches, etc. complete with clamps, trays, ferrules etc. All cable

shall be of FRLS copper conductor cables.

7.2.2 DRAINAGE AND DEWATERING SYSTEM.

2 sets submersible type or pump motor type pump motor sets of

adequate capacity shall be provided.

Out of these, one set will be in normal operation and other as standby.Piping and Valves: All piping required complete with necessary valves,

fittings etc.

Motor Control Centre: Motor Control Centre for all the above Two (2)

sets and to be located in pump room shall be provided complete with

suitable starter.

Cabling: All power and control cabling between the motor control

centre to pump motor sets and all devices such as level switches, flow

relays etc. complete with clamps, trays, ferrules etc. All cable shall be of

FRLS copper conductor cables.




7.2.3 COOLING WATER SYSTEM.

The cooling water for main plant shall be tapped from penstock before

BFV. The cooling water after circulation shall be discharged into tail

race. The supplier shall decide whether booster pumps are required for

circulation of water with sufficient pressure.

Piping and Valves: Piping, manifold and valves required penstock to

each equipment and discharge piping from each equipment to tail race.

Motor Control Centre : Motor Control Centre for all the above pump-

motor sets complete with suitable starter.

Cabling : All power and control cabling between motor control centre

and cooling water pump-motor sets complete with clamps, trays,

ferrules etc. All cable shall be of FRLS copper conductor cables.

NOTES:

Motors : All motors of auxiliary systems mentioned above shall be

suitable for operation at 3 phase, 400 V system, and shall have class F

insulation with temperature rise corresponding to class B insulation. All

motors and starters shall be suitable for 15 times on/off operation per

hour. Degree of protection for motors : IP-54.

7.3 COMPRESSED AIR SYSTEM.

7.3.1 OPERATION SYSTEM.

- Starting and stopping of the air compressors shall be carried out

automatically by pressure relays mounted to pressure system and to

general requirement air pressure reservoirs and by manual operation

from the motor control panel.

- Two Nos. of air compressor shall be provided one for normal

operation and other as stand-by. Normal operating air compressors shall

be selected as desired by change-over switch mounted on motor control

panel. The standby pump shall be selected automatically when air

pressure drops because of a trouble in the normal operating air




compressor or other reason. The air compressor shall automatically

stop when the pressure is restored.

7.3.2 ACCESSORIES OF COMPRESSORS.

Following accessories and fittings shall be provided to each set of air

compressors :-

-Water Separator : 1 set.

-Check Valve : 1 set.

-Unloader for starting : 1 No.

-Lubricating device : 1 set.

-Water flow relay (in case of water

cooling type) : 1 set.

-Cooling device : 1 set.

-Drain disposal device : 1 set.

-Interlock switch : 1 set.

-Pressure reducer ( to match required

brake pressure) : 1 set.

7.3.3 PRESSURE AIR RECEIVERS.

(a) Maximum and normal working air pressure, starting pressure of

the standby air compressor and alarm pressure shall be decided

through mutual discussion with Purchaser after the award of

contract.

(b) Air receivers shall be provided with the following accessories :-

i) Air pressure gauge (for : 1 No.

mounting to the turbine

control panel)

ii) Air pressure gauge (for : 1 No.

mounting to the air

pressure reservoir).




iii) Air pressure relays : 1 set.

iv) Feed air valves, exhaust

air valves, check valves,

drain valves & other stop

valves. : 1 set.

v) Safety valves : 1 set.

7.3.4 MOTOR CONTROL CENTER FOR COMPRESSED AIR SYSTEM.

From 400 V A.C. auxiliary supply scheme, one feeder shall be brought

to this motor control centre. Power cable for this purpose shall be

provided by the supplier.

Following equipment shall be provided by the supplier on the motor

control centre:-

1. Incoming Breakers : 1No.

2. Bus-Bars : Entire length of panel.

3. Feeder Breakers : 4 Nos. +2 Nos. spare.

4. Control Switches : ON/OFF Switch for each compressor.

Priority selector switchAuto manual switch

5. Indicators : ON/OFF/ Trip Lamps for each compressor.

6. Indicating Meters : i) 1No.Voltmeter with selector switch.

: ii) 1No. Ammeters with selector switch.

7. Starters : ON line starters.

8. Selector Switch : LOCAL/REMOTE for each compressor

9. Protection : thermal over current relay




7.3.5 PIPES AND VALVES.

All pipes and valves required up to the respective equipment shall be

supplied along with complete set of flange coupling, bolts, nuts and

packing. Main bus pipeline for braking shall be duplicated. All

compressed air piping shall be of seamless steel.

7.3.6 LUBRICANTS.

Sufficient quantity required for first fill of lubricant, grease, oil etc. plus

25% extra shall be supplied and included in bid cost.

7.3.7 CABLES.

Power supply cables and all control cabling from motor control centre to

compressors, receivers etc. is included in Bidder’s scope. Compressor

starting shall be regulated from the pressure switches provided on air

receivers. The motor control centre shall be located near compressor.

Cables from each auxiliary system equipment to its control panel (both

of which are included in supplier’s scope) shall be supplied. Cables for

interconnection between computer and computer based control panel

shall also be supplied. All cable shall be of FRLS copper conductorcables.

7.4 DRAINAGE AND DE-WATERING SYSTEM.

The drain water of entire power house and fire hydrant discharge will be

collected in Drainage and Dewatering pit located in the machine hall.

The supplier shall inform purchaser after detailed design and calculation

the size of pit required. For dewatering of draft tubes gravity drain shall

be considered. Necessary piping shall be laid by supplier up to the

Drainage and Dewatering pit. The water in the pit shall be discharged

at suitable location outside the power house.

Drainage and dewatering system shall comprise of following:




7.4.1 PUMP-MOTOR SET.

a) Pump: The pumps shall be of submersible type and sturdy and of

proven design with one or multi stage and with a double seal

fitted to pump shaft. The pumps shall be suitable to handle the

raw and unscratched water having turbidity of about 6000 ppm

without any damage or adverse effect to any parts of the pump.

The bowls shall be made of closed grain cast iron free of any

defects. The pump impellers shall be of one cast iron or phosphor

bronze and shall be dynamically balanced. Lockout shall be

provided to arrest the excess lift of impeller at the time of

starting. The pump bearing shall be of self-lubricated type. Fully

streamlined discharge case-cum non-return valve shall be

provided at the outlet of each pump. The non-return valve shall

be spring loaded needle type. Depending on the water level in the

sump pit the pumps shall start or switch-off automatically with

the help of float controls. All the control cables required for these

purpose shall be provided by the supplier.

b) Motor: Motor shall be of squirrel cage, induction type, 400 V, 3

phase, alternating current directly coupled to the pump and

forming a part and parcel of pump-motor set. The motor shall be

wet type.

DOL starter shall be provided. The motor shall be provided with

dual seal arrangement and sand guard for its protection from

outside water. The stampings used in motor shall be double

varnished to have better anti-rusting property. The rotor as well

as stator shall be vacuum impregnated with superior qualityvarnish and shall be baked under the controlled conditions to

ensure proper and long life. Stainless steel sleeves ground to

close tolerance shall be provided at the bearing locations. The

motor winding wires shall be made of water resistant type

insulation and shall be of copper. Bearing assembly shall be fitted




7.4.3 FLOAT CONTROLLERS.

Float controllers shall be provided in the sump pit. The control cables

from these controllers shall be taken to motor control centre for

regulation of motor starting.

7.4.4 MOUNTINGS AND SUPPORTING ARRANGEMENTS.

Foundation mountings for pump motors, supporting arrangement for

columns of suction and delivery pipes shall be supplied.

7.5.5 MOTOR CONTROL CENTRE FOR DRAINAGE AND

DEWATERING PUMPS.

From 400 V auxiliary supply scheme, one feeder shall be brought to

this motor control centre. Following equipment shall be mounted on the

motor control centre:

1) Incoming breakers : 1 No.

2) Bus bar : Entire length of panel

3) Feeder Breakers : Two numbers + Two numbers

spares.

4) Control switches : On/Off switch for each pump.5) Indicators : On/Off /Trip lamps for each pump

6) Indicating meters i) One No. Voltmeter with selector

switch.

ii)One No. Ammeter with selector

switch.

7) Starters 2 Nos on line starters.

8) Selector i) Local/remote for each pump - 2

Nos.

ii) Auto/manual for each Pump -

2Nos.

iii) Priority selector switch -1 No.




9) Protection : Thermal over current protection

10) Cables :- Power supply cables and all control cablings from motor

control centre to motors, load controllers etc. is included in

Bidder’s scope. Cables from each auxiliary system equipment to

its control panel (both of which are included in suppliers scope)

shall be supplied.

Motor starting shall be regulated from the float controllers provided in

drainage and dewatering sump.

7.5 COOLING WATER SYSTEM.

7.5.1 PURPOSE.

This system shall be used for supplying cooling water for following

purposes:

1) Cooling water for generators equipped with water cooled heat

exchangers

2) Cooling water for generator guide and thrust bearings

3) Cooling water for Turbine guide bearing and shaft seal.

4) Cooling water for Turbine governor oil pressure system

5) Other requirements if any.

The cooling water for main plant shall be tapped from penstock before

BFV. The cooling water after circulation shall be discharged into tail

race. The supplier shall decide whether booster pumps are required for

circulation of water with sufficient pressure. If booster pumps are

required then following specification shall be applicable.

One motor- pumps is specified for normal operation conditions and one

pump shall be provided as stand-by pump .




The above mentioned motor pumps will pump water from penstock and

supply to each equipment and discharge piping from each equipment

back to the draft tube.

Starting and stopping of the cooling water pump shall be normally

carried out by automatic control ( from main plant start sequence

program) and in case of trouble in the normal working cooling water

pump, the standby cooling water pump shall start automatically.

Besides, it shall be so arranged that the normal working and stand by

cooling water pumps can be started and stopped by manual operations at

the motor panel.

7.5.2 PUMP MOTOR SETS.

a) Pumps: - The pumps shall be centrifugal type and sturdy and

proven design with one stage and with a double seal fitted to

pump shaft. The pumps shall be suitable to handle the raw and

unscratched water having turbidity of about 6000 ppm without

any damage or adverse effect to any parts of the pump. The

impellers shall be made of cast iron or phosphor bronze and shall

be dynamically balanced. Lockout shall be provided to arrest theexcess lift of impeller at the time of starting. The pump bearings

shall be self lubricated type. Fully streamlined discharge case-

cum-non return valve shall be provided at the outlet of each

pump. The non-return valve shall be of spring loaded needle

type. All the control cables required for these purpose shall be

provided by the supplier.

b) Motors: - Motors shall be of squirrel cage, 400 V induction type,

3 phase, alternating current directly coupled to the pump and

forming a part and parcel of pump motor set. The motor shall be

wet type.

The motor shall be provided with dual seal arrangement and sand

guard for its protection from outside water.




The stampings used in motor shall be double varnished to have

better anti-rusting property.

The rotor as well as the stator shall be vacuum impregnated with

superior quality varnish and shall be baked under the controlled

conditions to ensure proper bonding and long life.

The motor winding wires shall be made of water resistant type

insulation and shall be of copper.

Bearing assembly shall be fitted with tilting pad bearings,

mounted on stainless steel balls, and shall be supported by

rocking pins. Bearings shall be suitable to absorb the vertical

thrust.

Suitable rubber diaphragm shall be provided to the motor for

pressure compensation.

All fasteners shall be chemically treated for protection against

rust.The entry of power supply cables to the motor shall be

through suitable cable gland, fitted on the body of the motor and

the cable entry arrangement shall be fully watertight. The bidder

shall furnish the details about arrangement of cable entry to

motor, in his bid including type of starter. Bidder shall alsosupply details of arrangement for disconnection of the cable

(outside the water) in order to remove the pump.

The pump shall have nameplate indicating:

Name of Manufacturer, Type, rating and rpm,

Serial number of pump, Q (discharge) and H (head) values for

duty point.

7.5.3 FILTER AND STRAINER

The cooling water from (penstock) shall be first passed through rotary

automatic cleaning water filter. The cooling water to be fed to shaft seal

and runner labyrinth shall be again passed through fine strainers. The

filters and strainers shall be provided as under : -




- Main rotary filter automatic & manual

- Fine filters for shaft seal (automatic and manual)

- Fine filter for runner labyrinth (manual)

- Strainer

The main strainer and filter shall have a capacity sufficient for passing

the cooling water requirement of entire power station.

The automatic strainer shall be capable of automatically changing over

by rotating the strainer at pre-determined intervals and cleaning inside

of strainer automatically. The design of manual strainer shall be such

that the cleaning is carried out by manual operations of valves.

7.5.4 MOTOR CONTROL CENTRE FOR COOLING WATER PUMPS

From the 400 V A. C. auxiliary supply scheme, one feeder shall be

brought to this motor control centre. Following equipments shall be

mounted on this motor control centre: -

1) Incoming Breakers : 1 No.

2) Bus-Bar : for the entire length of panel.

3) Feeder Breakers : 2 Nos. + 2Nos. spares.

4) Control Switches : ON/OFF switches

5) Indicators : ON/OFF / trip lamps.

6) Switches : i) 1 No. Voltmeter selector Switch

ii) 1 No. Ammeter Selector Switch

7) Indicating Meters : i) 1 No. Voltmeter

ii) 1 No. Ammeter

8) Starters : DOL type

9) Selector Switches : i) LOCAL/REMOTE for each pump.ii) AUTO /MANUAL for each pump.

10) Cables: Power supply cables and all control cabling from motor

control centre to pumps, float controllers etc. is included in

Bidder’s scope. Cables from each auxiliary system equipment to




its control panel (both of which are included in supplier’s scope)

shall be supplied. Cables for interconnection between computer

and computer based control panels shall also be supplied.

7.5.5. PIPING AND VALVES;

Piping, manifold, valves etc. required from penstock to each equipment

and discharge piping from each equipment to draft tube shall be

included in Supplier’s scope of works

7.5.6. PRESSURE GAUGES

Pressure gauges shall be provided as required.

7.5.7 PRESSURE CONTROLLERS

Pressure controllers shall be provided in the cooling water system. The

control cables from these controllers shall be taken to motor control

centre for regulation of motor starting.

7.5.8 MOUNTINGS AND SUPPORTING ARRANGEMENT

Foundation mountings for pump motor sets, supporting arrangementsfor suction and delivery columns shall be supplied.

7.6 STANDARDS

Equipment shall be in accordance with the latest IEC standards or

equivalent internationally accepted standards. Some of the standards are

listed below but shall not be limited to: -

IEC 298 - Cased equipment

IEC 264 - Common clauses, IEC 502 - M.V. Cables

IEC 227 - PVC Conductor and Cable.

IEC 287 - Calculations and Dimensions.

IEC 269 - Fuses.

IEC 364 - Installation




IEC 439 - Operating Mechanism, IEC 51-1 to 51-5

Measuring Devices.

IEC 145 & 521 - Counters, IEC 255 (1 to 22) - Relays

IEC 72 - Motors

IEC 404 - Magnetic Materials

IEC 349 & ISO 1996 - Noise

VDI 2056 - Vibrations

Swedish Standard 515 - Corrosion Protection

ASTMA 435 - Steel Plate Testing

ASME V - Welding Materials

ASTMA 609 & 709 - Cast Part testing

ASTMA 388 - Forged part testing

7.7. INSPECTION AND TESTS

The Supplier shall carry out inspection and tests at factory and site in

respect of auxiliaries as per the list given below

LEGEND

1. Material test

2. Non-destructive inspection of assemblies/components.3. Pressure test

4. Workmanship test

5. Assembly inspection

6. Operational tests

7. Commissioning tests

SUBMISSION OF TEST CERTIFICATES

The supplier shall submit 6 copies of test certificates to the Purchaser as

per the procedure given below:

i) FOR INSPECTION AND TESTING SPECIFIED TO BE DONE

IN PRESENCE OF PURCHASER.

Test certificates shall be submitted for approval.




ii) FOR ALL OTHER INSPECTION AND TESTING

Test certificates showing that the specified tests/inspection has

been carried out successfully by the Supplier, shall be submitted

for reference.

7.8 DRAWINGS AND DATA TO BE SUBMITTED WITH BID

Bidder shall submit in his bid information and general drawings

describing and illustrating the equipment he proposes to offer, in such a

manner as to make possible a complete understanding of the equipment

on which bid is based. The information shall include all essential

dimensions, types of materials to be used in major parts with the

chemical and physical properties of materials and the schematics, layout

drawings, control schemes and data for the:

1. Cooling water system

2. Drainage and dewatering system

3. Compressed air system

All “Data Sheets” enclosed with this section must be completely filled

in by the Bidder.

7.9 DRAWINGS, DESIGNS AND MANUALS TO BE FURNISHED

AFTER AWARD OF CONTRACT

These shall be submitted as per the list given in Annexure VII-I to this

section.

Mode of submission of drawings and designs will be intimated to the

successful Bidder in due course.

7.10 SPARES

Spares shall be supplied as per list under Section III of this Volume.




10. Pipe layout of drainage and

dewatering system 6 For approval

11. Schematic of drainage and


12. Motor Control centre panel for

drainage and dewatering system 6 For approval

13 Interconnection and wiring

diagram and cable schedules

of equipment 8 For reference

14. Foundation / support

arrangement of, 6 For approval

* Cooling water pumps

* Drainage/dewatering pumps

* Compressor air equipment,

air receivers

* All water piping, valves

pump columns

* Switchgear panels of cooling

water, drainage/dewateringand compressed air system.

DATA

1. Adequacy of cooling

water system 3 For approval

2. Adequacy of dewatering and

drainage pit size and volume 3 For approval

3. Adequacy of pump capacity for

cooling water, drainage and


4. Adequacy of compressed air




DATA SHEETS

COMPRESSED AIR SYSTEM

-Total number of compressors

-Discharge of one compressor at working rated

pressure

-Rated working pressure of compressor

-Rated power of compressor motor

-Rated speed of compressor motor

-Total number of air tanks

-Volume of one air tank for general

requirement

-Air leakage during operation

………. N m3 /s

........ …. kg/s

... …………MPa

………….. kW

………….. rpm

................

............ m3

... ... kg/s




COOLING WATER SYSTEM

TECHNICAL DATA SHEET FOR SUBMERSIBLE MOTOR PUMP-UNITS

ALTERNATIVELY TURBINE PUMP - MOTOR SET

Cooling Water Pumps Offered

Value

Quantity ..........

Type of operation ..........

Manufacturer

Type ..........

Rated speed .......... rpm

Discharge heads .......... m

Corresponding

Discharges Qn (at Hn) .......... m3 /sec

Efficiency (nominal point) .......... %

Power Rating .......... kW

Motor Voltage -------------

Type of starter --------------




DRAINAGE AND DEWATERING SYSTEM

TECHNICAL DATA SHEET FOR SUBMERSIBLE MOTOR - PUMP UNITS

ALTERNATIVELY TURBINE PUMP- MOTOR SET

Drainage Pumps Offered Values

Quantity ............

Type of operation

Manufacture ............

Type

Rated speed ............ rpm

Discharge ............. m3 /sec

Heads Hn ............. m

Corresponding

Discharges Qn (atHn) ............ m3 /sec

Efficiency

(Nominal point ............. m3 /sec

Motor power kW ............. kW

Materials

body .............

Impeller ............

Shaft ............




SECTION NO. VIII

TECHNICAL SPECIFICATION OF GENERATORI N D E X

Sr.No. Description PAGE

NO.

8.1

8.2

8.3

8.4

8.5

8.6

8.7

8.8

8.9

8.10

8.11

812

8.13

Scope

Standards

Type and main characteristics

Particular mechanical design characteristics

Particular electrical design considerations

Performance Guarantee

Technical specifications of Generator.

Technical specifications of Static Excitation

Factory test for Generator-Motor and related

equipment.

Material test

Site tests for Generator and related equipment.

Drawings, Designs, Studies and Manuals to be

submitted by the supplier after award of

contract

Spares

ANNEXURE

Annexure VIII-1

DATA SHEETSData Sheets

211

211

212

212

213

215

216

249

258

259

266

270

270

271

276




SECTION VIII

TECHNICAL SPECIFICATION OF GENERATOR

8.1 Scope :

This section covers technical specification of one number of three phase

vertical shaft synchronous generator and related equipment including static

excitation equipment.

The generator shall be of 15 MW rated output, 0.9 p.f.,11 KV, 375 rpm. 3 ph.

50 Hz, Vertical shaft synchronous Generator and capable of giving

continuous output of 110% of rated output. The generator shall be suitable

for direct coupling to the turbine specified under Section –V. Any fittings,

accessories or apparatus which may not have been specifically mentioned in

these specifications but which are indispensable for reliable operation of the

plant shall be provided by the Supplier at no extra cost to the Purchaser.

8.2 STANDARDS

The applicable standards but not limited to :

1) IEC..... 34 ( parts ...........)

2) VDE Standards of group 05303) IEC 85 (Insulation classes)

4) ANSIB 49-1-1967 Shaft couplings, Integrally Forged

Flange type for Hydro Electric units.

5) N.E.M.A. LG 2 “Vertical Hydraulic Turbine

Generator Shaft Run out tolerances” shop check or IEEE 810

whichever stipulated severe conditions.

6) V.D.I. 2056 for provisions regarding Radial Vibration Amplitudes.

7) V.D.I . 2060 for provisions regarding Rotor balancing.

8) “Rathbone curves” for provisions regarding Radial & Axial Vibration

accelerations.

9) I.E.C. 287 - Calculation of continuous current rating

(100% load factor).




Rated frequency is 50 Hz. The supplier shall guarantee rated

continuous output within the range of frequency from 47.5 Hz. to 51.5

Hz and voltage range of 0.9 Un to 1.1 Un.

Supplier shall furnish information regarding outputs available below

47.5 Hz. (47 and 46 Hz) and duration of such output. Rated power

factor is 0.90 (over excited) - 1.0-0.90 (under excited)

The most unfavourable sudden two phase terminal short circuit at

nominal voltage, 50% pole short-circuits with simultaneous over speed

for 3 seconds shall be considered. No damage whatsoever must occur

to the generator itself and the foundations in either case.

2) STATOR WINDING CONNECTION

The stator winding shall be star connected and neutral point to be

grounded through primary of power or voltage transformer and

resister.

3) Winding Insulation Class

The stator and field windings shall be entirely insulated with class F

materials (thermosetting type).

4) Wave form and Telephone Harmonic Factor ( THF)

The wave form of the open-circuit terminal voltage shall not deviatefrom a true sine wave by more than 5%. The Telephone Harmonic

Factor shall not exceed 1.5%.

5) Limits of Temperature and Temperature Rises

The maximum output which should be available at its terminals at

power factors cos ∅ 0.9(over excited)...1...0.90(under excited) shall

be 18.333 MVA .

When the generator operates at rated output, power factor, speed and

voltage, the stator and field winding temperature rise of generator

measured by embedded thermostat temperature detector and resistance

method shall not exceed 750

C & 850

C respectively.

When the generator operates at maximum output, rated power factors,

speed and voltage, the stator and field winding temperature rise of




1) Efficiency Guarantee: - The efficiency of the generator shall be guaranteed

by the supplier. The efficiency shall be determined by the summation of

losses method as specified in IS 4889- 1968 or /and latest amendment there to

and shall be subject to the tolerances specified in IS: 4722 -1968. Any

shortfall in the values of guaranteed parameters shall be subjected to penalty

or rejection as given in Volume-I.

6.2 Output and Temperature rise Guarantee:-

The hydro generator shall be guaranteed to give its rated and 10% overload

output at rated voltage and power factor without exceeding the temperature

rises. Any shortfall in the values of guaranteed parameters shall be subjected

to penalty or rejection as given in Volume-I.

The contractor shall be given all reasonable opportunities to make good and

meet the guarantees before the application of penalty or rejection of hydro

generator as a result of above clauses.

8.7 TECHNICAL SPECIFICATION OF GENERATOR

1) All material to be used shall be suitable and adequate for the purpose

intended and shall conform to the IEC standards.No patching, blocking, shimming or any other similar means of

overcoming defects, discrepancies or errors shall be permitted without

approval of Purchaser.

The generator design shall be such that the movements and

deformations due to temperature variations are compensated and the

loads and resulting forces, which would act on the foundation, are

substantially reduced. It should further be ensured that:

i) No buckling of stator core laminations takes place.

ii) The concentricity and the size of air gap shall remain

unchanged.

The unit shall be designed for unit assembly during erection and for

the removal of the complete assembled generator rotor during major




maintenance programs. This design shall permit the assembly and

dismantling operations to be performed as conveniently and quickly as

possible with the facilities of the powerhouse crane. Entire stator and

rotor shall be built at site to avoid any deformation in transit. Proper

stator and rotor lifting device for connecting to power house crane

shall be provided. The necessary information regarding the shape of

the hooks shall be taken into consideration.

Supplier shall declare along with bid his work plan for stator and rotor

building at site on service bay, built up in situ or partial building on

service bay and situ. Periods for such activities shall be distinctly

shown and his proposal for execution of job shall be declared in the

bid. Bidder shall note that entire stator and rotor are to be built at site.

Considerations in the design shall be given to the following

requirement for maintenance program.

-The largest component of the turbine shall be capable of withdrawal

through the stator bore after removal of the unit superstructure and

generator rotor.

- Rotor field poles shall be arranged in such a manner as to permit easy

removal with the rotor in place. Field pole electrical connections shallbe located in a position to facilitate ease in inspection, separation and

reconnection.

-The phase terminals of the windings shall be brought out of the

generator concrete housing for proper connections with bus duct. The

neutral terminals of the phase shall be brought out separately to

abominate current transformers before forming the star point of the

winding (Please refer the single line diagram). The two ends of field

windings shall be connected to two slip rings mounted on shaft.

2. STATOR GENERAL

The stator shall consist of a frame with air/water heat exchangers on its

outer periphery, built-in laminated core with radial air ducts and bar




winding in slots. The stator frame shall also support the upper bearing

bracket, upper deck and the bushing of the phase bus bars and

generator neutral connection. A portable, steel fabricated, inspection

ladder shall be provided.

STATOR FRAME

The stator frame shall be fabricated from steel plates and shall be of

welded construction. The frame shall be sufficiently strong to

withstand the most severe forces during the abnormal conditions e.g.

sudden short circuit & faulty synchronisation. Air coolers shall be

mounted around the outer periphery of stator frame. The frame shall be

provided with adequate number of horizontal stiffeners.

STATOR CORE

The stator core shall be made of low loss, high grade, non-ageing,

silicon magnetic steel laminations having a favourable bending co-

efficient. The lamination shall be accurately punched and deburred so

as to obtain very smooth surface at winding slots and keys slots. Each

lamination shall be coated on both sides with class F insulating layer toeliminate inter lamination and eddy current circulation.

The stator core shall be built up in stacks of equal height as far as

possible, the bottom and top most stacks shall give a special treatment

so as to form solid mass.

While stacking the lamination, intermediate pressure treatment shall be

given several times and the whole core should be pressed at both ends,

by means of clamping rings with fingers pressing over teeth portion to

ensure high tightness and mechanical strength of the core. The stack

of laminations must be firmly anchored to the frame and pressed

together in a firm and uniform way, which does not require

readjustments after installation. In particular, vibration of stator as a




conditions but also under severe fault conditions. The insulation on

the stator coils shall be sufficiently durable so that in case it is

necessary to remove coils, removal and replacement may be effected

without damage to the insulation of any of the other coils. The quality

and life of the insulation shall not be impaired in attaining the above

requirements. Class F insulation of proven design and which has

shown no breakdown shall be used. The details of the installation

where such insulation system is used shall be stated in the bid.

Generator winding cyclic & ageing tests (see IEC-34-18-1/1992-02-

Functional evaluation of insulation system for rotating machine.) to

determine the life span under cyclic thermal loadings shall be

conducted by the Bidder. If the supplier has already conducted such

tests at shop, type test reports shall be furnished with the bid.

The construction of winding bars and the winding in slots shall be fully

explained with drawings and detailed description.

The class F insulation system used shall be proven. The bidder must

furnish examples where the same system is used and is in trouble free

operation.

Corona shielding applied to the fully insulated bar shall have thefollowing structure.

The straight part of the bar shall be covered with a conducting varnish

(outer corona protection) in order to avoid potential differences

between the surface of insulation and the core iron. The bend end

portions of bars are covered with a semi-conducting varnish and in

addition a special tape be wound over a certain portion to ensure the

desired potential distribution (Capacitive control of potential

distribution). These measures would avoid creeping discharges along

the surface of insulation or even a breakdown.

The bars shall be carefully inserted in slots and properly aligned. It

shall be ensured that the wedges are firmly and permanently seated and




there are no possibilities of damaging the core lamination edges in the

slot. Rewedging should be virtually not necessary.

The packing shall be effective in both the circumferential and radial

directions. When installed, the coil sides shall be tight within the slot

so that a 0.5 mm. filler gauge will not enter any gap between the coil

and slot sides. The 0.5-mm. fillers gauge “no-go” standard shall apply

to at least 90% of the stacked core length. The remaining 10% has

individual ‘go ‘ length of less than 0.80 mm.

After final wedging, there shall be no measurable radial clearance

between the coil and slot or wedge. Slot wedges shall be of phenolic

or glass-reinforced polyester material, highly resistant to thermal

ageing and designed to minimize any tendency to relax the radial

pressure exerted on the coils.

The stator coil insulation, wedging, packing, brazing and tying shall be

such as to minimize the effect of thermal shock and of additional

differential expansion which may occur as a result of the cyclic

loading.

End connections of the stator coils shall be made at the top of winding.

The end portion of the winding shall be rigidly supported to preventany movement and distortion even under the most unfavourable short

circuit conditions. No metallic part, which does not correspond to

class F, shall be used for this purpose.

The slot portion of the bars must be manufactured to close tolerances.

No grinding of insulation will be permitted to achieve required

dimensions.

The connections between half coils shall be covered in the ends by

glass fiber insulation caps.

Bracing shall make all connections in end windings. The strands of

corresponding upper and lower layers bars shall be soldered at the

connecting end using copper clips to ensure adequate mechanical

strength and conductivity. A fiberglass-insulating cap shall be placed




over each connection and filled with an epoxy compound to secure it

to the ground insulation.

The winding overhang portion shall be rigidly supported, lashed

together by impregnated glass cords so as to form a rigid cone, which

can withstand the forces due to a sudden short circuit. The system

must be described in bid. Circulating primary split-phase current

under normal operating conditions shall be less than 2.5% of total rated

phase current.

Each winding bar shall be subjected to tangent delta measuring kV test

in shop and the dielectric losses of each coil shall be measured in the

factory and also after assembly at site.

Resistance elements for temperature recorder shall be mounted at 6

positions in the portions where the stator coils of each phase are

presumed to show the highest temperature.

3) ROTOR GENERAL

The rotor shall consist of a spider, laminated rims with brake ring at

the bottom, salient poles with field coils and damper winding cage as

well as upper and lower shafts to be bolted to the upper and lowerflanges of the hub.

ROTOR SPIDER

The rotor spider shall be of fabricated structure. High strength high

yield steel shall be used in the construction of the central hub and the

radial arms.

The attachment of laminated rotor rim with the spider arms shall be

designed to withstand the maximum forces induced in the runaway

condition of the unit.

The arrangement of arms shall not only compensate the expansion and

contractions during operation of generator but also those due to

welding.




Approved tests for material and welds such as X-ray and ultrasonic

tests and/or liquid penetration tests to ensure the reliability of the

whole spider shall be conducted.

ROTOR RIM

The rotor rim shall be of laminated floating type i.e. it should be

attached to the spider by means of wedges driven in between the key

supports on spider arms and the slots on the inner periphery of the rim.

The rotor rim shall be made up of circular segmental punching from

sheet steel, stacked overlapped layer by layer around the outer

periphery of the spider. The laminated rims shall be clamped to a

compacted ring of solid segmented end plates by means of high tensile

axial bolts so as to ensure firm mechanical connection between the

adjacent segments of any two layers for transmission of tensile forces.

The shape and geometry of laminations and the pattern of stacking

shall be such that the completed rim corresponds to an ideal

homogenous cylinder as the uniform distribution of mass. The brake

ring shall be provided at the bottom of rim. The brake ring may be

constructed in segments so as to allow any replacement.

ROTOR POLES

The pole body shall be made up of steel laminations made of same

material as is used in construction of rim laminations. The pole

laminations shall be held tight between end plates by means of suitable

number of bolts.

The poles shall be secured to the rim by means of wedges in such a

way as to allow the removal of poles in the vertical direction without

requiring removal of the rotor out of the stator bore.




FIELD COILS AND DAMPER WINDING

The field coil shall be made up of turns of flat rectangular copper cut

to appropriate length and width. To increase the cooling surface area,

alternate turns shall be provided with conductor of greater width so as

to form on the outer side, a finned surface.

The insulation system of class ‘F’ shall be used to ensure compact

assembly with excellent electrical and mechanical properties. The turn

insulation should be thoroughly cemented to adjacent turns to permit

removal of field pole coil as a unit. The pole core insulation must be

separate from the coil. Special attention shall be paid to ensure

prevention of end turns of a coil from deforming or slipping due to

centrifugal forces on the inter-connections. End turn insulations must

be reinforced if necessary.

The field coils of poles shall be connected by means of flexible copper

plates to form as field winding whose ends are brought out for

connection with slip rings.

The coils shall be tested at medium frequency test voltage or impulse

voltage test on the terminals. During this test, the magnetising current

must be measured and this current shall not differ by more than 10%between various coils. Low resistance damper winding of fully caged

construction shall be provided to improve stability under fault

conditions and specially to reduce voltage disruption under conditions

of single-phase fault.

SLIP RINGS

The slip rings shall be in an accessible location above the rotor. The

slip rings shall be so arranged as to minimize the possibility of an

operator causing a short circuit between slip rings while changing or

adjusting the brushes. Provisions shall be made for reversing the

polarity of the slip rings to obtain uniform wear on both slip rings.

The maximum run out of the slip rings shall not exceed 0.25 mm. The




brushes shall be staggered, and the slip rings shall be so located that

they will not interfere with the removal of the upper guide bearing.

The brushes and slip rings shall also be so positioned as to avoid

contamination by oil vapour or oil leakage from this bearing. The lead

from the slip rings shall run directly to the field breaker and discharge

resistor. An extra set of slip ring brushes, insulated brush holders, and

terminals shall be provided. One 45 mV drop shunt to be mounted in

the generator field leads shall be furnished complete with calibrated

shunt leads for connection to a field current ampere meter.

A separate slip ring and brush assembly shall be mounted on generator

shaft for the field winding earth fault relay and the leads shall be

terminated in the generator terminal box.

The slip ring and brush gear shall be separately enclosed from the

generator housing. It shall be so arranged that ventilating air from the

ring and brush gear housing cannot enter the generator housing. This

will prevent suspended carbon dust from the brushes entering the

generator housing.

A self-fan or motor fan shall be provided for cooling and exhausting

the carbon dust. Isolating switch for the fan motor shall be locatedwithin the brush gear housing.

4) BRACKETS

UPPER BRACKET

Upper bracket shall be designed to accommodate combined thrust and

Generator upper guide bearing and also to lift the complete stator from

erection bay to the generator pit. It shall also support top flooring.

The flooring shall be divided into a number of sections so as to allow

withdrawal of air/water heat exchangers and or rotor poles.




all high pressure piping, flexible hose, strainers, regulators and check

valves.

The control equipment shall be of the heavy duty type. One pressure

gauge to indicate establishment of oil film shall be provided having

two sets of adjustable, electrically independent contact (both set closed

at normal operating pressure and open at low pressure), one set to be

used as an interlock to prevent starting the generator unit, if pressure to

establish an oil film is not available and the other set to be used for

operation of indicating lights. The contacts shall be suitable for use in

220V D.C. circuits. Suitable damping devices shall be provided in the

high pressure piping system, if necessary to prevent undue pulsations

of the pressure gauge. The pumping unit shall be of sufficient capacity

to force the oil completely between the thrust bearing surfaces when

the unit is at standstill. The high pressure oil grooves on the bearing

pads shall be so designed that they will not interfere with normal

lubrication of the bearing while the high pressure system is shut down.

The control arrangement for the pumps shall be subject to purchaser’s

approval and shall include provisions for remote control of the system,

annunciation or failure of the A.C. motor driven pump, and automaticstart of the stand-by D.C. motor on failure of the A.C. motor - driven

pump.

The bearing oil shall be cooled by means of externally placed oil /

water heat exchangers. The cooling capacity shall be 150%. The

cooling tubes shall be of non-corrosive metal e.g. stainless steel and

shall be tested to a hydrostatic pressure of 1.5 times of maximum

pressure for a period of 10 minutes. The cooling water supply system

shall be designed jointly by turbine and generator suppliers.

Manufacturer shall supply all necessary valves and controls. The main

shut off valve for the bearing water supply shall be A.C. motor

operated with manual override.




journal surface of the upper guide bearings. Effective means shall be

provided for cooling the bearings. Water cooling for the separate

guide bearing design shall be similar to that of the combined guide and

thrust bearing.

Each guide bearing shall be equipped with the following : -

- 1 No. Oil-level relay in the bearing reservoir with high and low

level alarm contacts.

- 3 Nos. Dial type temperature controllers two nos. embedded in

the bearing metal to indicate the temperature of the bearing and

one no. thermometer in the oil. The controllers shall have two

sets of electrical contacts. The controllers shall also have a

contact to indicate loss of bulb pressure or loss of power to the

instrument. The indicator shall be mounted on the gauge

panel.

- 3 Nos. Resistance temperature detectors. Two Nos. shall be

located in recesses in the bearing metal on diametrically

opposite sides of the bearing and one in the oil, with leads

brought out to the terminal box.

- 1 No.Direct-reading water flow gauge with two low-flow alarmcontacts.

- One Oil-water contamination detector.

Adequate baffles shall be provided, if necessary to prevent excessive

churning or aeration of the oil.

Each lubrication system shall include suitable oil reservoirs, supply

and drain oil piping, valves, including valve bypass piping for flushing

the lines and necessary appurtenances. Oil filters of the low pressure

drop type shall be provided in the oil supply line to the thrust bearing

oil circulating system.

Supplier shall provide the initial supply of lubricating oil required to

fill the entire lubricating system. The quality and the specification of




permitted. Provisions shall be made for mechanical blocking the rotor

in the fully raised position. The blocking device shall be such that it

will be unnecessary to maintain hydraulic pressure on the jacks while

the rotor is in the raised position.

A brake dust extraction system shall be provided by the supplier. A

position switch having two sets of contacts shall be provided for each

brake shoe. One set of open contacts (when brakes ‘OFF’) shall be

wired in parallel and will be used for brakes ‘ON’ indication. The set

of closed contacts (when brakes ‘OFF’) shall be wired in series and

will be used in the unit start interlock circuit. Wires from both sets of

contacts shall be brought out and terminated in the generator terminal

box. The equipment shall be complete with necessary control cabinet,

piping, valves, fixtures etc.

7) SOLE PLATES AND FOUNDATION BOLTS

The supplier shall provide adequate number of soleplates, anchor bolts

etc., for fixing lower bracket and stator frame to foundation. The

whole anchorage shall be designed and constructed to resist the forces

under most abnormal condition, resulting from sudden short circuit orfaulty synchronising. The supplier shall furnish the detailed drawings

& calculations to the Purchaser for his consent and approval.

8) AIR COOLING SYSTEM

The generator shall be cooled by means of closed circuit ventilating

system. The cooling air shall be circulated to effectively and

uniformly cool the rotor poles, the stator winding, the stator core along

the coil and peripheral areas. The complete details of the system shall

be furnished in the bid. To facilitate inspection and cleaning of the

windings and to permit removal and replacement of field poles and

stator winding coils, the air baffles provided to control the direction of

air flow shall be so designed that they may be removed in segments,




with relative ease. Hinged panels in the baffles may be supplied to

permit convenient access to parts of the unit. The circulating air shall

be of cooled by air / water heat exchangers evenly spaced around the

stator frame. The air shall be cooled to a temperature not exceeding

450C. Baffles shall be provided for separation of the generator air

cooling system from the Turbine pit. The air/water heat exchangers

shall have sufficient capacity to maintain the cooled air temperature

not exceeding 450

C. on the housing unit, with cooling water inlet

temperature of 350

C, when one exchanger is out of service and the

unit is in operation at full power. The discharge pressure at the exit of

the heat exchanger shall be sufficient to discharge the water to draft

tube.

The air cooling coils shall be stainless steel or copper nickel material

and able to withstand a test pressure equal to double maximum

working pressure for a sufficient length of time to permit adequate

inspection of leaks. The heat exchangers shall be equipped with

suitable automatic air vent valves and the entire system shall be

provided with suitable drain outlets. The pressure drop through the

cooling heat exchangers shall be stated by supplier. The heatexchangers shall be provided with connections having brass plugs in

an accessible position, one on the supply and one on the discharge

pipe, to permit the attachment of a manometer. The heat exchangers

shall be conveniently located to facilitate cleaning without removing

them from the generator. To minimize the frequency of maintenance

each heat exchangers shall be provided with 20% additional cooling

coils to maintain adequate cooling during service even if some of the

tubes are clogged.

The supplier shall supply all piping, including terminations to the

outside of the unit housing. The discharge water piping will be

terminated similarly and supplied by supplier. All cooling water




piping shall be lagged with approved insulation to prevent

condensation.

Main water piping for the cooling water shall be of mild steel of

appropriate strength with valves for open / close operation at the water

entry and exit of each cooler element. Cooling water piping inside the

barrel shall be provided with anti-condensation paint. The manifolds

of cooling water supply and exhaust pipe inside the generator housing

shall be placed in a trench below the walkway in the housing. Cooling

elements shall be arranged in such a way that the cooling water always

remain in the heat exchangers.

Access to all tubes for inspection and cleaning shall be possible

without disturbing the header piping.

The heat exchangers shall be mounted in such way as to facilitate

assembly, dismantling, maintenance and repairs. They must be

interchangeable between each other. The necessary water headers

shall be furnished with the heat exchangers. All connections between

coolers and headers shall be of flange type. Isolating valve shall be

provided in each connection between each coolers and headers so that

any heat exchangers can be removed without interfering with theoperation of remaining coolers. Approved means for draining and

releasing entrapped air of all coolers and pipe work shall be provided.

Condensed water on cooler surfaces shall be collected in receiving

dishes installed below the coolers and drained to the station drainage

pit. All piping shall be of flanged construction, using standard piping

sizes suitable for its function. The system shall be provided with the

following :

2 Nos. resistance temperature detectors (pt. 100 ohm), one mounted

suitably for measuring the cooling water inlet temperature and other

mounted for measuring the cooling water exhaust temperature.




One or more resistance temperature detectors for each exchanger

mounted with suitable mechanical shields to measure the

temperature of the cooled air entering the generator rotor.

Resistance temperature detectors shall be supplied in accordance with

the relevant IEC- standards. The location and method of mounting of

these resistance temperature detectors shall be such as to avoid the

necessity for removing the resistance temperature detectors when the

exchangers are removed from the machine for servicing.

One approved direct-reading type water flow gauge with low-flow

alarm contacts shall be fitted on the exchangers. The indicating dials

shall be mounted on the gauge panel.

Dial-type indicating thermostats with adjustable alarm contacts shall

be supplied and installed in the inlet air path entering each exchanger

and for the discharge air from each exchanger. The indicating dials

shall be mounted on the gauge panel. All gauges required to ensure

proper functioning of the cooling system shall be provided by supplier

and all alarm contacts and solenoids shall be suitable for 220V D.C.

9) HEATERSAdequate no. of electric heaters, designed and located conveniently

within generator housing to prevent condensation of moisture or

sweating during idle periods shall be provided. Heaters shall be

designed and wired for operation of a 400-V, 3-phase, 4 wire circuit.

The supplier shall furnish all wiring within rigid conduit between the

individual heaters and heater circuits terminal box which shall be

furnished for installation, within the generator housing or at other

approved locations, except that flexible conduit may be used for

connections to the individual heaters when required. Provision shall be

made to switch on the heater automatically by thermostatic control

whenever the generator is shut down. The thermostatic control device




for switching on the heater shall be of the differential type with

adjustable differential range of 0-100C approximately.

10) SHAFT AND COUPLINGS

The generator shaft shall be of one single piece and shall be coupled

with the turbine coupling and thrust collar. The upper guide bearing

collar shall be forged integral with the shaft. Shaft shall be of forged,

open hearth or electric furnace, carbon or alloy steel and properly heat

treated in one piece and coupling with thrust collar is also acceptable

but detailed description of design, fixation of shaft and thrust block

and generator for trouble free operation shall be proven.

The shaft shall be machined accurately all over and polished at the

guide bearing region. At least two concentrically true polished surface

bands at approved location for dial type eccentricity indication shall be

available.

All half coupling of the shaft shall be of the integrally forged pattern.

Coupling dimensions for connections of turbine to generator shall be

agreed upon by the generator and the turbine suppliers and shall be in

accordance with relevant IEC standards.The generator supplier shall provide the generator and turbine shaft

coupling and the coupling bolts and nuts as well as the nut guard on

the turbine side of coupling. The coupling bolts shall be provided with

locking devices and shall have dimensions and tolerances in

accordance with reverent IEC standards.

Design of shaft assembly for the complete set (turbine and generator)

shall be done jointly by the turbine and generator suppliers, who will

solely be responsible for calculations of the first critical speed.

Ensuring the correctness of the shaft length and coupling flange

machining shall be the combined responsibility of both suppliers.

Generator supplier shall be responsible to shift the turbine shaft to his




work and return the same when done with. Cost therefore is deemed to

have been included in the bid price.

Drilling of coupling boxes in the upper flange of turbine shaft and that

on lower generator coupling flange shall be performed in generator

supplier’s works.

11) RUNNER AND MAIN SHAFT

The turbine shaft shall be before hand completely machined with

coupling bolt holes drilled 3 mm. under size. Generator supplier shall

be responsible and shall take extra care in the final reaming of the

coupling bolt holes and the coupling and aligning of the turbine shaft

and generator spider before shipping to site. The supplier will also

supply the steel drilling template and pin gauge for the coupling. The

main shaft shall be material inspected by radiographic inspection or

ultrasonic inspection and after confirming no defect existing inside, the

final machining shall be proceeded.

The coupling between the turbine shaft and generator spider shall be

sized to suit relevant standards. The coupling shall be amply strong to

transmit the power involved and in addition, carry the downward thrustof the turbine. For the protection of the bearings from damages due to

shaft current, a perfect insulation shall be done in the supporting part

of the thrust collar.

The critical speed of the main shaft due to unbalance of the rotating

parts shall be higher than 120% of the maximum momentary speed

which may happen at the transient time such as load rejection of

runaway condition of the turbine. The supplier shall prepare shaft

critical speed computer analysis which shall be approved by Purchaser.

The following design and machining tolerances shall apply to the

driving disc, runner plate and coupling flange where applicable.

- Where the thrust load is supported by the bottom surface of a driving

disc or shaft flange, the following tolerances shall apply. The surface




generator housing shall also form part of supply. Doors shall be

airtight, lockable and interlocked.

13) GENERATOR TERMINAL BOX, ELECTRICAL ITEMS AND

WIRING & PIPINGS.

All electrical items supplied by supplier shall comply with the

appropriate sections of the relevant IEC standards. They shall be

arranged in a manner approved by the Purchaser. The supplier shall

provide and install terminal boxes in locations approved by Purchaser,

and shall provide and install all wiring and conduit from its electrical

components to these terminal boxes. All wiring shall be standard wire,

with oil proof insulation. Further a common marshalling box shall be

provided. Wiring from all individual terminal boxes shall be brought

by the supplier up to this marshalling box. Leads for all auxiliary

electrical circuits such as current transformers, resistance elements,

limit switches; various kinds of relays shall be supplied up to the

terminal blocks installed in the air housing.

All wiring within the generator housing, including main field leads,

lighting, resistance temperature detectors leads and control andindicating leads shall be adequately clipped or otherwise supported and

protected. The wiring shall be bundled and tied together, where

possible, to provide a neat arrangement. The wiring passing through

openings in metal members of the generator, or otherwise passing over

or near metal edges, shall be carefully protected against abrasion.

A cable trough shall be provided by supplier, mounted to the inside

surface of concrete air housing and extending around the complete unit

for carrying the wiring. To facilitate disconnecting the generator field

leads when removing the top bracket, supplier shall supply and install

a junction box just inside the stator casing at a suitable location and he

shall supply and install the field leads from the slip rings to this box,

with cable terminals at both ends. These leads will be extended by




cables or insulated bars, supplied and installed by the Supplier from

the junction box to the field circuit breaker. Supplier shall supply and

install a cable through inside the casing to carry the cables of bars from

the slip rings to the junction box and to the point of exit through the

casing.

In general, close attention shall be given in order to prevent failures or

shutdowns occurring as a result of generator vibration. The wire

insulation shall be resistant to flow and abrasion under the conditions

to which it may be exposed. Liquid type flexible conduit shall be used

where wiring may be exposed to oil or water leakage.

All piping shall be supplied such as feed / drain oil pipes of the

generator bearing oil tank, oil jacks, piping of oil level relays and oil

level gauges, feed / drain water pipes for bearing coolers and air

coolers, connecting pipes between respective coolers, drain pipes of

leakage oil and leakage water at respective positions and other piping

installed in the generator air housing and barrel including valves and

flanges.

14) GENERATOR HOUSING LIGHTINGSuitable lighting, which shall also include the area under the generator

rotor, and a minimum of four convenient outlets, shall be provided in

the generator housing. A terminal box shall be supplied to terminate

the supply leads, lighting, wiring etc. Supplier shall supply and install

lighting control switches at service door.

15) GENERATOR FLOORING, PLATFORMS ETC.

All necessary floor plates and curbing including floor covers for all

pipe and cable trenches as required for completing the floors on and

around the generator and their related installation shall also be

supplied. Floor plates shall be of anti-skid type or similar safety

pattern. The generator shall be provided with suitable platforms,




stairways, handrails etc. for access to various generator parts.

Necessary hooks, pulleys etc., for handling shall be provided. Suitable

guards, over and around all energised or moving parts shall be

provided for the generator and their accessories. Wherever required,

suitable mesh wire barriers shall be provided within the generator

housing / pit for protection of workmen while generator is in operation.

16) CREEP DETECTORS

- A creep detector shall be provided complete with all necessary

wiring and controls to perform the following functions.

- When the unit has been brought to rest by closing of the guide

vanes and application of brakes, the detector shall operate if

shaft rotation occurs after expiration of the normal stopping

period. The total rotation required to operate the detectors shall

not exceed 10 degrees of shaft movement. On operation the

detector shall perform the following functions.

- Close an annunciation contact which shall be wired to the

generator terminal cabinet.

- When the high pressure oil pump provided for unit starting andstopping is on “automatic” control, start the high pressure oil

pump.

- De-energize the brakes if the brakes are on “automatic” control.

- When the unit is started under normal control, detector shall be

disconnected to prevent spurious control and annunciation

signals.

17) TEMPERATURE DETECTORS

The Supplier shall provide six resistance temperature detectors (pt. 100

ohm at 0 degrees C) per parallel circuit per phase, embedded in the

various parts of the stator winding in accordance with relevant IEC

standards.




Twelve resistance temperature detectors (pt. 100 ohm at 0 degrees C)

shall be embedded in a suitable location, six at each end of the stator

core for temperature measurement for the detection of end iron

heating.

Twelve resistance temperature detectors shall be equally spaced in the

stator core for temperature measurement at 12 teeth locations.

RTD’s and hotspot temperature indicator shall be furnished.

Requirements of temperatures to be measured have been described;

however supplier shall decide number of scanners required. The exact

location of the temperature detectors in the stator winding and core

shall be subject to the approval of purchaser. All temperature detectors

in and around the generator shall be wired to the terminal box mounted

on the outside of the generator air housing. This terminal box shall be

separated from other terminal boxes.

All connections from the temperature detectors to the terminal boards

shall consist of twisted leads in shielded cables. The leads from each

stator bearings, water and air temperature detectors shall be brought in

a neat and substantial manner to suitable terminal blocks located in a

terminal box on the generator barrel. This box shall be usedexclusively for resistance temperature detectors. The terminal box, to

be provided by supplier shall have provision for connection to external

conduit and wiring. The leads shall be supplied as twisted three wire

leads suitably shielded and otherwise protected to minimize stray

“pick-up”. The insulated leads shall be capable of with-standing an

applied potential test of 2000V to ground for 1 min. Separate

terminals shall be provided for terminating the shields of individual

Resistance Temperature Detector (RTD) leads. The resistance

temperature detectors shall be platinum type and have a resistance of

100 ohms at 00C. Resistance ratio between 0

0C and 100

0C shall be

1.3926.




updraft etc. The system shall also be designed in such a way that

steam is generated in sufficient amount so that air is displaced and

extinguishing of fire is quicker.

Following points shall be considered in the design of components: -

i) ATOMIZED WATER SPRAY NOZZLES

Nozzles shall be specially designed having three parts of holes

arranged, in such a manner that jet of water flowing out of one

hole strikes against the jet of water emerging out of another hole

at right angle such that the collision of two high velocity jets

results in very fine fog formation required for extinguishing the

fire.

ii) PIPES & FITTINGS

Steel tubes with thread flange joints shall be used. The tubes

shall be suitably bent to size at factory for ready installation.

iii) WATER MOTOR GONG

The jet of water itself shall operate a gong to give an alarm.

iv) INLINE STRAINER

For cleaning the water of impurities, foreign particles etc.suitable strainer is required. This shall be made of stainless steel

and shall be installed in the pipeline itself. Arrangements for

cleaning the strainer shall also be provided.

v) VALVE

A suitable valve shall be provided in the pipeline, which should

open automatically in case of fire and allow water to the ring

headers. Details thereon shall be described.

vi) DRAIN VALVE

A drain valve should be provided in the pipeline to drain the

water.




output of main channels. If this channel fails then the controls shall be

automatically switched to standby channel.

The normal mode of operation shall be auto-control. Additionally,

manual control of the excitation shall be available for testing and

setting up purposes or in unlikely event of failure of the auto control of

both channels.

The auto-control circuits shall consists of two interdependent feed back

control loops (Voltage and Current) with limiting circuits for under-

excited MVAr, rotor heating, current and power system stabilisers.

The excitation system shall be capable of switching from 25% of rated

generator voltage and at 60% of voltage it shall be capable of

supplying rated excitation current. The time constant of excitation

system shall be less than 0.10 sec.

2) CAPABILITY

With rated generator voltage, the excitation system shall be capable of

delivering continuously, within rated temperature rise, any value from

0 to 120% of the field current required when the generator is operating

at 110% of rated voltage, and rated power factors at 0.90 (over-

excited). With rated generator voltage, the excitation system shall becapable of providing a ceiling current to the field of not less than 1.5

times rated field current for at least 30 seconds. De- excitation time

between rated voltage and 10% of voltage shall not be more than 10

sec.

3) SYSTEM RESPONSE

With the generator initially at rated apparent output power, rated

voltage, power factor and speed, the excitation system shall be capable

of changing from rated field voltage to 100% of ceiling voltage within

25 to 30 ms. for a sustained drop in generator terminal voltage of 10

%. The rated voltage shall be calculated assuming that at rated

apparent power, field winding is operating at rated field current.

Response in the negative (reverse) direction to suppress terminal




8.8.2 DIGITAL VOLTAGE REGULATOR

1) Micro-processor based voltage regulator shall be digital type. It shall

be liberally designed so as to be as reliable as possible and shall

incorporate sufficient redundancy so that failure of any control

equipment will not cause mal-operation of the system.

2) The digital voltage regulator should periodically calculate the control

signal from measured and reference values. Calculation should be

repeated at every short time intervals where by an apparently

continuous regulator output characteristic is produced.

3) Calculation is to be carried out in binary system. The analog measured

values of generator voltage and current as well as field current must be

transformed in an Analog / Digital converter into binary signals. From

the calculated control signals, pulses should be generated for firing the

thyristor.

4) Various control functions like voltage regulation, limitations of field

current, rotor angle, stator current, slip stabilising etc. shall be stored as

programs to be executed in a cyclic pre-programmed manner.

5) Control to maximum converter voltage shall be achieved in less than

10 milliseconds thus ensuring fast reaction to network disturbances.6) Internal conditions monitoring of devices with light emitting diode

(LED) indication be provided which means short failure detection

times.

7) Set values shall be digital, absolutely reproducible and not vulnerable

to changes ensuring long term stability

8) Number of different units shall be small so that spare parts stock could

be kept to a minimum.

9) Low sensitivity to external electro-magnetic influences shall be

ensured which means high noise immunity.

10) Electrical control points shall be bare minimum to reduce potential

trouble sources.




8.8.3 THYRISTOR CUBICLE

1) This cubicle contains full three phase thyristor bridges with its

associated equipment. The design should be modular in such a way

that changing of a thyristor or part of a bridge shall be easily possible.

In case forced ventilation system is adopted, noise level outside the

panel shall be negligible.

2) Number of thyristor cubicles provided shall be such that, even with

failure of one thyristor bridge, the generator should be able to supply

rated output and with failure of two bridges, the generator should trip.

3) All thyristors shall be fuse protected. Voltage safety factor for

thyristor, defined as the ratio between the maximum operating voltage

and the rated peak cut-off voltage shall be more than 2.5. Excitation

response shall not be less than 4.0 s.

4) Suitable protection shall be provided for thyristor to prevent voltage

spikes from reaching them and damaging them.

5) Over voltage protection to protect the thyristor bridges and the field

circuit shall be provided.

8.8.4 SWITCHGEAR EXCITATION CUBICLE

This cubicle shall contain all switchgear equipment necessary for the

operation of excitation.

Field breaker and all equipment necessary for rapid suppression of

generator-motor field circuit shall be provided. The principle of

suppression of field shall be the reversing of rectifier operation into an

AC converter operation and shunting the generator field terminals by a

discharge resistor. Over-voltage protection devices, start-up excitation

devices, auxiliary relays and contactors shall be provided.

All in feeds from station battery shall be taken through D.C./D.C.

converters. Redundancy shall be built in, in modules.




16) Total losses at rated load should be at minimum.

8.8.6 Lightning Arrestors, Voltage Transformers, Surge protection capacitors and

Neutral grounding equipment are included under Section X Generator

supplier shall coordinate with the supplier of these equipments in respect of

characteristics and performance requirements of these items.

8.9 FACTORY TESTS FOR GENERATOR AND RELATED EQUIPMENT

Tests to be conducted in factory on various material, assemblies etc. on

generator at different stages of manufacture are indicated in the enclosed

statements. legends of the nomenclature of tests is as below ;

LEGEND FOR FACTORY TESTS OF ELECTRICAL LOT

1) Test at shop on random sample of raw material.

2) Test at shop on random sample of raw material and on semi or fully

finished part.

3) Test at shop on 5% of consignment .4) Check straightness of bolts taking random sample of 10 bolts per

machine.

5) Test at shop in the presence of Purchaser’s representative.

6) Test at shop on each piece.

7) Spot check at shop of brazed parts of semi or fully finished parts.

8) Test at shop on random sample of one per sheet.

9) Test at shop on complete sheet.

10) Test at shop - once per item.

11) Test to be conducted by manufacturer and Test Certificates given to

Purchaser.




SUBMISSION OF TEST CERTIFICATES

The Supplier shall submit 6 copies of test certificates to the Purchaser as per

the procedure given below :

i) FOR INSPECTION AND TESTING TO BE DONE IN PRESENCE

OF PURCHASER’S REPRESENTATIVE.

Test certificates shall be submitted for approval.

ii) FOR ALL OTHER INSPECTION AND TESTS

Test certificates showing that the specified tests / inspection has been

carried out successfully by the Supplier shall be submitted for

reference.

8.10 MATERIAL TEST

Sr.N

o.

Particular of Test 1 2 3 4 5 6 7 8 9 1

0

1

1

1) ROTOR RIM SHEETS:

Tensile Test √ √

Chemical analysis √ √

Visual check √ √ √

Dimensional check √ √ √

2) ROTOR RIM BOLTS

Tensile Test √

Chemical analysis √

Visual check √

Dimensional check √ √

3) FIELD WINDING (POLE COIL)

FINISHED

Tensile Test √




Sr.N

o.


0

1

1

Visual check √

Dimensional check √

Test for short circuited turns √

Acceptance test of each piece √

Insulation Simulation Test √

4) POLE FINISHED

Visual check √


High voltage test √

Test for short circuited turns √

Weight check √

Acceptance Test of each piece

(H.V.Test)

√

5) DAMPER BAR

Hardness Test √

Visual check √


Electric conductivity Test √

Acceptance Test on 5% of

consignment

√

6) DAMPER SEGMENT RAW

Hardness Test √

Visual check √


Acceptance Test on 5% of

consignment

√

7) POLE LAMINATION SHEETS




Sr.N

o.


0

1

1

Tensile Test √

Chemical Analysis √

Visual check √ √

Dimensional check √ √ √

Induction Test √

8) POLE AND PLATE RAW

Tensile Test √

Notched Bar Impact Test √

Chemical Analysis √

Ultrasonic Test √

Visual Test √

Dimensional Test √

Acceptance Test of each piece √

9) POLE END PLATE MACHINING

Visual check √






Sr.No Particular of Test 1 2 3 4 5 6 7 8 9 1

0

1

1

10) POLE BOLTS

Tensile Test √




11) ROTOR LAMINATION

Tensile Test √

Notched Bar Impact Test √ Chemical Analysis √

Ultrasonic Test √ √

Aging characteristic √


12) STATOR LAMINATION

SHEETS

Tensile Test √




Induction Test with determination

of specific losses at 1.0 and 1.5 t

√

13) STATOR PUNCHING

Tensile Test √




14) STATOR RIM BOLTS




18) OIL COOLERS (EACH)

Tensile Test √

Visual Test √


Hydrostatic Test √

19) GENERATOR SHAFT

Material Analysis √

Tensile Test √

Notch Impact Test √

Visual Inspection √

Magnetic particles Examination √

Ultrasonic Test √


Roughness Test √

Baroscopic Inspection √

Matching with Pump-Turbine shaft √

20) BRAKE AND JACK

Visual Test √ √ √ √

Dimensional check √ √ √ √

Measurement of Stroke

Hydrostatic Test √ √ √ √




Sr.

No.


0

1

1

21) E.T.D. THERMOMETER

THERMAL SWITCH

Calibration Test √

Check and setting of switches and

relays

√

22) VARIOUS SWITCHES AND

RELAYS

Check and setting of pressure,

Level, Flow

√

Temperature switches and Relays √

23) STATIC EXCITATION

EQUIPMENT

A) FOR EACH SET

H.V. Test √

Functional Check of modules by

simulation

√

Control sequence interlock Test √

B) FOR ONE SET

Load Test and current sharing Test

on thyristor bridge

√

Heat run test on thyristor bridges √

Heat run and Impulse test on

excitation transformer

√




8.11 SITE TESTS FOR GENERATOR AND RELATED EQUIPMENT

Site tests to be conducted on various assemblies in presence of

Purchaser are as below but shall not be limited to.

DURING ERECTION

STATOR WINDING :

- D.C. Resistance.

- Insulation Resistance.

- H.V. Test

- Dielectric Test.

ROTOR WINDING :

- D.C. Resistance

- Insulation Resistance.

- H.V. Test

- Rotor Impedance.

- Dielectric Test

- High frequency induced voltage test on poles.

MEASUREMENT OF CENTERING AND LEVELLING- Together through upper bracket, Stator Core, Lower Bracket and

Turbine Upper Cover and Casing.

UPPER AND LOWER GUIDE BEARING

- Insulation Resistance

- Check of vibration response

- Check of setting of oil level switches.

SHAFT :

- Check of shaft alignment together with Turbine Shaft.

- Check of vibration response.

- Check of slip ring deflection.




HIGH PRESSURE INJECTION OIL SYSTEM FOR THRUST BEARING:

- Check of settings of pressure switches, relays etc.

- Check of pumps

- Operational check in all modes.

BRAKE AND JACK SYSTEM

- Check of setting of pressure switch, limit switches,

relays etc.

- check of pumps.

- Operation pump check in all mode.

STATOR FINISHED

- Magnetic flux test

- Di-electric Test.

- Measurement of stator winding resistance D.C. resistance.

- Measurement of stator winding insulation resistance.

- Measurement of stator winding impedance.

- H.V. Test

- Check of concentricity of core.

- Check of core height.

ROTOR FINISHED- Measurement of Rotor winding D.C. resistance.

- Measurement of rotor winding impedance.

- Measurement of rotor winding insulation resistance.

- H.V. Test

- Check of concentricity.

DURING PRECOMMISSIONING AND POST COMMISSIONING

1) AUXILIARIES

Auto/Manual operation of all auxiliary system connected with

Generator .




2) OTHER GENERATOR TESTS

NO LOAD TESTS :

- Initial run

- Check of smooth run at gradually increased speed from zero to

rated speed

- Vibration and noise level measurement

BEARING HEAT RUN

- Running test of bearings

- Recording of bearing metal and oil temperature at rated speed

no load until all bearings reach stable temperature.

OVER SPEED TESTS

- Functional check of vibration & seismic monitor

- Run for 2 minutes at 150% over speed.

EXCITATION SYSTEM

- Commissioning test .

SYNCHRONISING TEST

- Auto / Manual synchronising.

LOAD REJECTION TESTS

- Load rejection at 1/4, 1/2, 3/4 ,1.1& 1.0 of rated output at ratedpower factor.

- Oscillograph measuring of voltage rise at each rejection.

SHUT DOWN TESTS

- Normal stopping operation of generator

- Quick shut down tests.

- Emergency shut down test.

- Vibration and noise level measurement.

LOAD TESTS

- Check of operation of various controlling and regulating.

- Temperature recording of windings and bearings.

- Vibration and noise level measurement.

- Measurement of thrust bearing bracket deflection.




6) STATIC EXCITATION SYSTEM

- Measurement of insulation resistance.

- H.V. Test. .

- Functional test of system component.

- Loading characteristic test.

- Measurement of range of voltage regulation.

- Measurement of range of power factor regulation.

- Test of generator current limiter and exciting current limiter.

8) GENERATOR CHARACTERISTIC AND PERFORMANCE

TESTS :

- Open circuit characteristic (without step-up power transformer).

- Three phase sustained short circuit condition characteristic.

- Line to line sustained short circuit condition (without step-up power

transformer)

- Various Reactances

- Measurement of Air gap

- Measurement of Noise level.- Measurement of Moment of Inertia.

- Determination of balanced and residual component of telephone

harmonic factor (THF)

- Measurement of following losses (according to IEC 34-2A

Calorimetric method)

i) Losses in active iron and additional no load losses in metal

parts.

ii) Losses due to friction and windage

iii) Stator winding copper losses at 750

C

iv) Additional load losses

v) Field winding copper losses at 750

C




vi) Excitation system losses (Excitation transformer + thyristors

+ ac/dc link)

vii) Electrical losses in brushes.

- Measurement of vibration and noise level at rated output

- Measurement of all bearing temperatures at rated output.

- Measurement of reactive power

- Determination of generator guaranteed output with reference to

guaranteed temperature rise.

- Determination of generator guaranteed efficiency

8.12 DRAWINGS, DESIGNS, STUDIES AND MANUALS TO BE

SUBMITTED AFTER AWARD OF CONTRACT BY THE BIDDER.

The list of drawings, designs, studies, data needed and manuals etc. required

to be submitted by the supplier is enclosed with this section (Please refer

Annexure VIII-1 - I).Mode of submission of designs and drawings will be

intimated to the successful bidder in due course.

8.13 SPARES

Spares shall be supplied as per the list under Section - III of this volume.




ANNEXURE VIII-1

DRAWINGS, DESIGNS AND MANUALS TO BE FURNISHED AFTER

AWARD OF CONTRACT.

Sr.

No.

Brief description within months

from the date

of award of

contract

Remarks

1 2 3 4

I GENERATOR

1. Arrangement drawings describing

and illustrating the information of:

3 For approval

* General layout drawing

*Combined turbine and Generator

cross section

* General arrangement and

overall dimensions of

generator showing

position and marking of main and

neutral leads, important elevations

etc

* Thrust and guide bearing Assembly

* Air circulation arrangement

* Excitation system

* Description of thrust bearings

and data regarding

construction, adjustment,

accessibility and method.

* Description and section of stator

and rotor insulation




2. Installation, assembly drawings of :

1 2 3 4

Generator and turbine shaft

coupling

8 For approval

Top and bottom brackets 8 For approval

Thrust and lower guide bearings 8 For approval

Upper Guide bearing 8 For approval

Rotor 8 For approval

Stator Foundation 6 For approval

Stator windings 10 For approval

Rotor arrangement including poles 10 For approval

Slip ring arrangement 10 For approval

Generator brakes 10 For approval

Assembly of stator and rotor with

lifting arrangement

10 For approval

Speed sensing element

arrangement

10 For approval

Vapour seal assembly 10 For approval

Lifting beam and attachment

drawing

6 For approval




3. Drawings illustrating dimensional details with schematics for :

1 2 3 4

Lubrication and cooling system

of thrust and guide bearings

10 For approval

Generator cooling with heat

exchangers, air guides etc

10 For approval

Turbine- Generator gauge panel 10 For approval

Schematic diagram of air, oil

and water piping

10 For reference

Schematic diagram of brake &

jack system

10 For reference

Thermometers, R.T.Ds etc 10 For reference

General scheme giving details of

excitation system, D.V.R.

Thyristors, field breaker, field

discharge resistance, etc.

10 For reference

Arrangement of generator heaters 10 For reference

Arrangement of rotor pit on

service bay, Rim building stools

and loading on service bay floor.

6 For approval

Arrangement of staircase, hand-

rails, doors, coverings etc.

10 For approval

Arrangement of oil cooler

withdrawal

10 For reference

Schematic diagram of thrust

bearing High Pressure injection

of lubrication system

10 For reference

4 Layout, plan and cross sections of

floor openings for piping, cables

6 For approval




MANUALS.

1 2 3 4

1 Manual for storage, preservation

and handling of the supplied

goods

18 For reference

2 Manual for erection /

dismantling, testing and

commissioning of the supplied

goods

18 For reference

3 Manual giving operating

instructions for all the ‘DO’s and

‘DONT’s’

20 For reference

4 Manual giving detailed

maintenance schedule

20 For reference




DATA SHEETS

1) Name of Manufacturer :- ………….-------------------

--

2) Manufacturers type

reference

:- -------------------------------

---

3) Type :- ----------------------------

4) Line voltage

Rated

Maximum

Minimum

:-

:-

:-

-----------------kV

-----------------kV

-----------------kV

5) Normal Synchronous

speed ( For a system

frequency of 50 Hz)

:- ----------------rpm

6)

A)

Guaranteed continuous

output under temp. rise

conditions specified in

item 6 (b) and under the

terminal conditions of

a) Rated output at 11 kV ,

0.9 power factor (lag)

b) ) Maximum continuous

output at 11 kV , 0.9

power factor (lag)

:-

:-

---------------------

---------------------

B) Maximum temperature

rise for the rated output

and continuous maximum

output over and above the

cooled air temp. of 450c




with temp. of cooling

water not exceeding 350c

a) stator winding by

RTD

b) stator winding by

resistance

c) other parts by

thermometer

Rated output

-------------------

-------------------

-------------------

Maximum continuous

.output

-------------------

-------------------

--------------------

7

A)

Guaranteed overall

efficiency of the

generator at 11 kV

terminal voltage 0.9.

power factor (lag) and

rated speed and 750c wdg

.temp by summation of

losses method as per IS

& subject to tolerance as

specified in IS

i) 110 % of rated

load

ii) Full load

iii) ¾ full load

iv) ½ full load

B) Guaranteed

arithmetical mean of

above efficiencies.

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

8 Inherent regulation i.e

Increase in voltage at

constant Speed and

excitation on taking off




9)

i) 110 % of rated

load

ii) Full load

iii) ¾ full load

iv) ½ full load

Generator Reactances

a) Synchronous reactance

( saturated )

i)Direct Axis –xd

ii)Quadrature axis-xq

b) Direct axis transient

resistance

i) saturated

ii) unsaturated

c) Sub transient reactance

i)Direct Axis –xd

ii) Quadrature axis-xq

d) Negative phasesequence reactance

e) Zero phase sequence

reactance

f) Resistance of armature

winding at phase at 75

0c

g) Resistance of field

winding at750c

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

---------------------%

-------------------ohm

-------------------ohm

10) Generator Time constants :-




a) Direct axis transient ,

open circuit

b) Direct axis transient

short circuit

-------------------Sec

-------------------Sec

11) Generator characteristics

curves :-

a) open circuit

characteristics curve

b) Full load saturation

curve

i) Zero power factor

ii) 0.9 power factor

c) Generator power

capability diagrams

:-

------------------------

-------------------------

-------------------------

------------------------

------------------------

12) Short circuit ratio -------------------------

13) Synchronizing power ( at

11 kV) Full load, 50 cycle

, 0.9 p.f.(lag)

-------- -- kW/Electrical

radiation

14) a) Fly wheel effect of the

rotating parts of the

Generator and exciters.b) Inertia constant

--------------Tm2

---------KW Sec/kVA

15) Stress levels.

a) Maximum speed ---------------------rpm




(Runaway speed)

which all parts are

guaranteed to

withstand safely for 5

minutes

b) Name and location of

parts having the least

factor of safety under

runaway or short

circuit condition

c) Guaranteed minimum

factor of safety based

on yield point of

material at runaway

speed

--------------------------

-------------------------

16 Embedded temperature

detectors in

a) stator winding

i) Number

ii) type

b) core

i) Number

ii) Type

c) teeth

i) Number

ii)Type

-------------------------

--------------------------

-------------------------------

---------------------

-------------------------------

--------------------

17 Static Excitation

equipment

a) Name of manufacturer

:-

-------------------------------




b) Type

c) Continuous rating of

excitation equipment

d) Ceiling Voltage and

duration

e) Primary Voltage rang

allowed for

continuous operation

f) Minimum primary

Voltage for ceiling

operation

g) AVR output range

h) Accuracy of AVR

control

i) D.C battery equipment

j) Looses at full load in

static Excitation

equipment

k) No. of Thyristorbridges

l) Excitation

Transformer

a) Rating

b) Type

c) Basic Impulse level

-------------------------------

----------------…………

-------------------------------

----------------------

---------------------------

-------------------------------

-------------------------------

-------------------------------

------------………………..

--------------------------

-------------------------------

-------------------------------

--------------------kV(peak)

18) Generator coolers

a) No of air coolers

b) Maximum safe water

----------------------

---------------kg/cm2




pressure

c) Cooling water

requirement at 350c

and for full load on

generator

i)Quantity of water

ii) Water pressure

d) Temp. of cooled air

under condition c )

--------Ltr/minutes per

cooler

-----------kg/ cm2

--------------------0c

19 Stator

a) Material of stator

core

b) Insulation of

lamination

c) Stator frame

construction

d) No of sections in

which divided for

transport

e) Insulation of stator

winding

f) Stator

i) Height including end

winding

ii) Diameter at air gap

---------------------------

---------------------------

---------------------------

-------------------------------

----------------------

--------------------mm

--------------------mm




iii) outside diameter of

frame

iv) shape

v) Weight

--------------------mm

--------------------mm

--------------------kg

20) Generator Housing

a) Height

b) Diameter (D)

c) No. of generator pit

heaters

d) No. of temp. detector

for fire protection

--------------------mm

--------------------mm

------------------------

------------------------

21) Rotor

a) Construction of field

poles

b) Method of attaching

field poles on rotor

rim

c) Rotor rim material

and construction

d) Rotor spider material

e) Field winding

construction

-------------------------

------------------------

------------------------

-----------------------

----------------------

-----------------------

--------------------




f) Insulation of field

winding

g) Construction of

damper winding

h) Air gap width

i) Factor of safety at

max. runaway Speed

based on yield point

of material

-----------------------

-----------------------

--------------------mm

---------------------

22) Shaft

a) Material

b) Diameter

c) Length

d) Diameter of axial

holes

e) Weight

f) Diameter of coupling

flange

------------------------

------------------------

------------------------

-------------------------

--------------------kg

--------------------mm

23) Thrust and guide bearing

a) Cooling water at




350c required

j) Quantity

ii) Pressure

b) Location of bearing

c) Thrust bearing and

guide bearings

i)Type

ii)Diameter of

bearing

iii) Bearing area

iv) No of pads

Thrust Bearing

-------------

--------------

------------------

------------------

--------------------------

-------------------------------

--------------------

--------------------------

Guide Beaing

------------------------

------------------------

-----------------------

------------------------

24) Bearing (Bracket)

Material and construction --------------------------

25) Height that the rotor must

be raised to dismantle the

thrust bearing

--------------------------

26) Generator brake and jacks

a) Air pressure range for

the brakes forsatisfactory operation

b) Speed at which

brakes are to be

applied during

normal shut down

---------------------

--------------------------




c) No of brakes

d) Stopping time of

generator

-----------------------

-----------------------

27) Oil pressure for jacking ---------------------

28) Capacity of jacking pump --------------------lpm

29) Lubricating system

A) Oil

a)Specifications

b)Quantity for filling

i) Thrust and guide

bearing system

ii) Lower guide

bearing

c)Oil cooling

arrangement

d) Description of

arrangement

to prevent

circulating current

in the bearing

-----------------------

-------------------------

-----------------------

-----------------------

--------------------------

30) Weight of generator

rotating parts.

--------------------------

31) Weight of complete

generator

--------------------------

32) Total load on thrust

bearing

( including hydraulic

thrust etc.)

---------------------------




33) Heaviest package for

shipment

a) Name

b) Weight

c) Dimension

--------------------------

------------------------

------------------------

34) Largest package for

shipment

a) Name

b) Weight

c) Dimension

-------------------------

------------------------

35) Heaviest Assembly to be

lifted by power house

crane

a) Name

b) Weight

c) Dimension

-------------------------

--------------------------

-------------------------

36) Largest assembly to be

lifted by the power house

EOT crane




a) Name

b) Weight

c) Dimension

------------------------

-----------------------

-----------------------

37) Recommended crane

capacity

--------------------------




TABLE NO.1

GUARANTEED VALUES OF GENERATOR LOSSES AND EFFICIENCY AT RATED VOLTAGE Un a

No. Losses (According to IEC 34-2) Symbol unit Apparentterminals

Smax= 110 %MVA

Losses in active iron and additional no loadLosses in metal parts

Pfe kW

1 Constantlosses

Losses due tofriction andwindage (*)

Turbine bearing losses Pu.g.b kW

Generator bearing losses Pl.g.b. kW

Windage and friction losses Pwi+f kW

Brushes losses Pbr kW

2 Excitationparameters

Field voltage Uf V

Field current If A

3 Load losses Stator windings copper losses at 75° C Pcu 1 kW

Additional load losses Padd. kW

Field winding copper losses at 75° C Pcu2 kW

Excitation system losses (excit trasf. +thyristors + ac/dc links)

Pe.s kW

Electrical losses in brushes Pe.br kW

4

:

SUMMATION OF LOSSES I p kW5 CALCULATED GENERATOR EFFICIENCY f i G.c6 GUARANTEED GENERATOR EFFICIENCY f jG.g




TABLE NO.2


No. Losses (According to IEC 34-2) Symbol unit Apparenterminal

Smax110 % MVA


Pfe kW

1 Constantlosses






2 Excitationparameters Field voltage Uf V

Field current If A





Pe.s kW


4 : SUMMATION OF LOSSES I p kW5 CALCULATED GENERATOR EFFICIENCY f i G.c6 GUARANTEED GENERATOR EFFICIENCY f jG.g




TABLE NO.3


No. Losses (According to IEC 34-2) Symbol unit Appatermin

Smax110 % MV


Pfe kW

1 Constantlosses






2 Excitationparameters

Field voltage Uf V

Field current If A





Pe.s kW


4

:

SUMMATION OF LOSSES I p kW5 CALCULATED GENERATOR EFFICIENCY f i G.c6 GUARANTEED GENERATOR EFFICIENCY f jG.g




SECTION –IX

SUPERVISORY CONTROL AND DATA ACQUISITIONSYSTEM




SECTION NO. IX

Supervisory control and data acquisition system

I N D E X

SR.

NO.

Description PAGE

NO.

9.1

9.2

9.3

General Requirements

Computer based SCADA system

Unit control Board

Departure from specification

Data Sheets

294

295

305

309

310




SECTION IX

SUPERVISORY CONTROL AND DATA ACQUISITION SYSTEM

9.1 GENERAL REQUIREMENT:-

1 Comprehensive system for automation of the power station

complex as a whole shall be provided by the supplier.

2. The plant to be controlled shall consist of the following:-

i) One No.:- Turbines-Generator set including all connected

auxiliaries.

ii) Station service auxiliaries

iii) 220 kV switchyard equipments.

3. The system shall use the most up to date & proven technology

based on microprocessors reliable transducers which require no

or little maintenance and/or calibration during services.

4. The system shall be arranged to provide (2) two levels of controls

:- viz

i) “Plant Control” in automation mode from Unit Control

board or from LCD console.

ii) “Unit control,” in manual mode, from Unit Control board

or from respective control cubicles ( Generator excitation

cubicle, auxiliary equipment control board and generator

metal clad switchgear cubicle/etc.)

5. Normally, the plant control in remote automatic mode shall be

used. When the communication link is not available, or when the

equipment in Central Control Room is being inspected and/or is

under repairs, the control and monitoring functions of the unit

can be performed in Unit Control in “Manual Mode,”.




9.2 COMPUTER BASED SCADA SYSTEM :-

9.2.1 System:

Computer based SCADA system shall be used. Computer based

SCADA system uses microprocessor based control technology

physically distributed through out the power house. The separate

microprocessor units are linked together by a number of digital

communication paths to form a completely integrated control system.

9.2.2 Control Parameters:

SCADA system should be complete with primary sensors, cables

analysers/transmitters, monitors, system hardware/ software and

peripherals etc. to monitor/control the following parameters.

• Generator stator and rotor winding temperatures

• Generator and turbine bearing temperature

• Lubrication oil temperatures

• Status of generator cooling system

• Governor control monitoring of turbine speed

• Generator terminal voltage, current, KW, KVAR, KVA, KWH, Hz,PF, field voltage and field current.

• Annunciation for violation of permissible limits of above parameter

• Turbine guide bearing temperature detector

• Generator guide & thrust bearing temperature detector

• Guide and thrust bearing oil level indicator

• Generator winding temperature detector

• Turbine speed

• Generator speed

• Governor oil pumps, oil pressure indicator and low pressure indicator

and low pressure switch




• Cooling water pumps, section and discharge pressure switch / gauge.

• Inlet pressure gauge at inlet of turbine

SCADA should provide monitoring of parameters listed above. The list

may have additional parameters as per requirement and shall be

finalised during design stage.

9.2.3 SCADA should have following controllers:

• Unit controller

• Common plant controller/ supervisory control

• Remote supervisory control

9.2.4 Unit Controller:

It is microprocessor based / PLC based and is required to perform all

functions as below. It is required to have capability to implement closed

loop PID function for governing and to perform all monitoring, control,

protection and recording functions that a power plant required

independently.

(a) It should monitor and control items

• Turbine wicket gate• Turbine/ Generator RPM

• Generator power out put

• Generator excitation

• Generator breaker

• Line breaker

(b) Automatic unit control modes should include following:

• Unit automatic start sequence

• Unit automatic shutdown sequence

• Unit automatic synchronizing

• Unit wicket gate set point control




• Unit load set point control

• Unit flow control

(c) The unit should include digital governor with proportional, integral

and derivative gains. The governor be with in a position loop controlled

by speed loop and capable of 0-10% droop. A manual position control

should be provided. Following governing functions should be provided.

• Speed evaluator

• Speed control

• Speed set point adjustment

• Gate limiter

• Start up and shutdown control of turbine

• Position controller for guide vanes with power amplifier for control of

servo valve.

(d) Unit Auto synchronization

The controller should automatically synchronize the generator to the bus

by reading the slip frequency (generator-bus) and adjusting the governor

speed set point until the correct slip frequency is obtained while sending

voltage raise/lower pulses to the voltage regulator to match generator

voltage to bus voltage. When the slip frequency is obtained and thegenerator and bus voltage are equal, the controller

shall send a close breaker command when the generator voltage and the

bus are in phase. An additional external synchro check relay should also

be provided to supervise the controller close breaker command and the

manual close breaker command. The controller should follow

synchronization limits in terms of breaker closing angle and voltage

matching condition specified by generator manufacturer.

(e) Shutdown sequence

The shutdown sequence provided by controller should be such that the

turbine generator set from any moving state to a complete standstill with




(vii) Reactive power control

The controller should have four reactive control modes, one manual and

three automatic. The generator capability curve should be entered into

the controller during configuring. All automatic reactive power control

modes should be limited by the generator capability curves. If an

operator enters a set point, that will take the generator outside its

capability curves, the reactive power control program should control

reactive power to get as close to the set point as possible, but remain

within the generator's capability.

• Manual:

The controller should provide operator capability, using "raise/lower"

keys on the VDT keyboard and the "raise/lower" switch on the manual

control panel to control voltage and reactive power.

• Automatic VAR control:

The controller should automatically control the generator output to that

VAR set point set by operator. The generator voltage limit and

capability curve should not be exceeded regardless of the VAR set

point.

• Automatic PF Control:The operator should enter power factor set point from the keyboard and

the controller should automatically control the generator output to that

power factor (leading or lagging) set point set by operator. The

generator voltage limit and capability curve should not be exceeded

regardless of the power factor set point.

• Automatic voltage control:

The controller should automatically control the generator output to

match that voltage set point set by operator. The generator voltage limit

and capability curve should not be exceeded regardless of the voltage set

point.




• Alarm Annunciation

There should be two types of alarms used by the controller. One type

should be the external alarms from contacts fed into the digital inputs of

the controller and the second, the internal alarms generated by the

controller. All alarms, whether internal or external, should be capable of

being configured to cause different sequences.

Unit controller should be capable of providing audible and visual alarms

in the event of faults occurring in the power plants. The instant the fault

occurs the relevant fault indicator is activated. All faults have to be

acknowledged by the operators and can only be reset when the fault has

been resolved. The list of faults on occurrence of which audible warning

should be given will be finalised during design stage. .(viii) Manual

control panel

The unit controller should have a manual control panel that bypasses the

processor and allows the generator to be operated manually. The manual

operation shall be done from UCB. The manual control panel should

include start relay circuitry that is station battery powered. Manual

switches to trip and close the breaker, turn the field on and off, start and

stop the turbine and raise and lower the voltage should also be included.The gate should be capable of manual operation by a potentiometer that

is located on a manual control panel and should be calibrated to position

within 0.1 percent.

(ix) Unit Protection

The protection system shall be based on the use of discrete

microprocessor based relays with the following features:

• Continuous self monitoring

• Online display of actual values

• Should be capable to communicate with supervisory system through

unit controller. Details of protection relays are covered in section -XI

.




(x) Supervisory Controller

It should monitor and control the status of power plant, provide

automatic unmanned operation, log data, display the process through a

mimics, Depending on the station requirements, the operator should be

able to enter set points for power output, voltage and power factor. It

should also have online documentation and expert diagnostics,

efficiency management and plant management.

9.2.6 Operator Interface Requirements:

The controller should use a video display terminal or PC as the main

operator console. It should have powerful graphical user interface to the

operators. The operator should be able to completely operate the plant

by typing commands/function key on the keyboard or by push button on

control panel. All information required to operate the plant should be

shown on the screen. A printer should be used to print out plant

information. Symbols and colours specified in the international standard

IEC 204 should be used for display.

9.2.7 Screen display:The screen display should include all metering, indication and

annunciator information normally displayed on a typical power plant

control panel. This should include all metered data such as three phase

generator volts and amps, generator watts, VARS, power factor, speed

and frequency. This display should also show generator stator and

bearing temperatures, breaker status, line volts, line frequency, and

kilowatt-hours. The time and date should also be displayed with time to

the minute. Screen data should be updated promptly whenever actual

data changes. Alarm and status information should be updated within

one second of actual changes. Analog data should be updated within two

seconds of a change. Calculated value such as temperature, watts,

VARS, and power factor should be updated within five seconds of an




actual change. All DC analog readings on the screen display should

have configurable scale factors. All except speed should have

configurable labelling on the screen.

The AC scaling should be configurable by specifying WYE or DELTA

and maximum AC voltage and current.

Data shown on the display should have the following minimum

accuracies.

AC Voltage 1% of full scale

AC Current .1% of full scale

Frequency ± .005 HZ

DC Inputs .25% of full scale

KW, KVAR, PF .25% of full scale

Temperatures + .5 degrees C

9.2.8 Annunciator display:

A portion of the screen should be dedicated for an annunciator. Alarms

should be displayed in order of occurrence with the oldest alarm at the

top of the screen. The sequence of alarms should be distinguishable if

alarms are more than 1/60 th of a second a part. The display shouldinclude space for a least 23 alarms. When an alarm clears, the alarm

below it should move up to fill in the blank space keeping the sequence.

No alarms should be lost. Any alarms that do not fit on the screen

should be saved until there is room. Alarms should flash until the

acknowledge key on the keyboard is pressed. If the alarm is still on after

it is acknowledged, it should stop flashing but remain on the screen. If

the alarm has cleared, it should be disappeared from the screen when the

acknowledge key is pressed.

The annunciator should display both alarms that are internally generated

by the controller and alarms that are sensed external to the controller.




9.2.9 Control status display:

The display should include an indication of the status of the turbine i.e.,

starting, stopping, synchronizing, etc...

9.2.10 Automatic control status display:

The display should show the current automatic control mode, its set

point, turbine gate limit, and any overriding control modes.

9.2.11 DT Keyboard:

The keyboard should be a standard keyboard with upper and lower

cases, ten key numeric pad and at least ten function keys. The function

keys should be assigned important functions.

The operator should be able to start and stop the turbine from the

keyboard using simple commands. The operator should be able to enter

set points via keyboard, select any one of automatic power control

modes and select any one of reactive power control modes

9.2.12 External Interface

Supervisory Controller should have a number of protocol moduleswhich should provide connectivity to other devices including remote

terminal units and programmable logic controllers.

9.2.13 Event Recording and Data Logging

(a) Data logging

Their should be a provision for a data logging printer at the plant to

provide data logging at adjustable intervals, trouble logs and operator

comments entered manually at the keyboard. The data logging interval

for each printers should be adjustable by the operator in increments of

one minute.




(b) Alarm and status logging

All alarms annunciated on the screen should be recorded on the data log,

time-tagged to 1/60 of a second resolution. Plant status or operational

changes should also be recorded on the data log, time-tagged to 1/60 of

a second resolution. The operator should be able to enter comments on

the log manually through the keyboard.

(c) kWH logging

Plant watthours should be accumulated and recorded on the data log at

both daily and monthly intervals. The integrated power generation

controller should have the capability to accumulate these data by one of

two methods: internally, by a calculation method based on direct

monitoring of generator CT and PT inputs, or externally, by receiving

and totalizing counts from pulse initiator output from an external

watthour meter.

9.3 UNIT CONTROL BOARD (UCB)

Unit Control Board shall be installed in Control Room.

Controls, Indications, Alarms etc. required on UCB are givenbelow :

1. All control switches required for manual operation shall be

mounted on this board.

2. Following control switches for Auto operation of plant shall be

provided on UCB

a) Unit Start/Stop

b) Auto/ Manual

c) Emergency Stop

3. Three annunciation windows shall be provided.

a) Operation indication window

b) 30 window annunciator for Electrical fault




c) 30 window annunciator for Mechanical fault

4. Digital clock for indication of time

5. Digital type temp. scanner (0-150oc) with selector switch for

temperature indication of selective equipments of power plant

such as stator, rotor, guide bearing etc. shall be provided.

6. Following meters shall be provided.

- Guide Vanes Limiter Position Indicator (0-100%)

- Guide Vanes Position Indicator (0-100%)

- Runner blades Limiter Position Indicator (0-100%)

- Runner blades Position Indicator (0-100%)

- Generator Voltage Meter with Selector Switch

(0-20 kV)

- Generator Current Meter with Selector Switch

(0-10 kA)

- Generator MW meter (MW-0-20 MW)

- Generator MVAr Meter

- Generator Power Factor Meter (0.9 over excited ....1.0

...0.9 under excited).- Frequency Meter 45-55 Hz

- Field Voltage Meter 0-500 V

- Field Current Meter 0-4000A

- Turbine Speed Indicator 0 to 500 rpm

- Speed/Load Setting Indicator.

- Running Hour Meter (Hours)

7. Dual channel AUTO/MANUAL Synchronizer shall be provided.

Auto synchroniser shall consist of following modules :-

PHASE DETECTION MODULE :

This module shall detect the phase difference between incoming




generator and grid voltage. Output of the module shall be a pulse

train whose width should vary as the phase difference.

FREQUENCY DIFFERENCE MEASUREMENT MODULE :

This shall measure the frequency difference between the

incoming generator and grid voltage in the frequency difference

of 0.01Hz to 1.00 Hz.

POLARITY MODULE :

This module shall compare the frequency difference obtained

with the set value. (The set value is the one which is set on the

front plate of the module) The module should then generate

control signals for frequency matching.

VOLTAGE DIFFERENCE MEASUREMENT MODULE :

This shall measure the voltage difference between the incoming

generator voltage and grid voltage and generate control signals

for voltage matching.

VOLTAGE COMMAND MODULE:

This shall issue final command to AVR for raising or lowering

the incoming generator voltage depending upon the measuredcondition. Interposing relays shall be provided for this purpose.

FREQUENCY COMMAND MODULE :

This shall issue the final command to the E.H.G for lowering or

raising the incoming generator frequency depending on the

measured condition. Interposing relays shall be provided for this

purpose.

BREAKER COMMAND MODULE :

After the voltage and frequency are matched this module shall

issue the closing command to the breaker. It should also take

into account the breaker closing time which can be set on the

front plate of the module.




AUTOMATIC POWER OFF MODULE :

After synchronisation, the feed back is received in this module

which shall switch off the auto synchroniser.

POWER SUPPLY MODULE :

This module should accept the input voltage of 230V A.C. and

generate necessary voltage required for functioning of auto

synchroniser.





(To be filled in by Bidder.)

Item Description of departure. Reference to clause in the specifications




DATA SHEETS

MAIN CONTROLLER UNIT CONTROL BOARD

Sr.

No.

Description Offered By Supplier

1 Manufacturer / Type :- --------------------------

2 No of CPU :- --------------------------

3 Characteristics of CPU :- --------------------------

3.1 Microprocessor :- --------------------------

3.2 Maximum memory capacity

( Program/data)

:- --------------------------

3.3 Maximum No of flags :- --------------------------

i) Retentive :- --------------------------

ii) Non Retentive :- --------------------------

3.4 Maximum No of Timers

0.01-9990s

:- --------------------------

3.5 Maximum No of Counters

0-999s

:- --------------------------

3.6 Max. Number of inputs/outputs :- --------------------------

i Digital inputs :- --------------------------

ii Digital outputs :- --------------------------

iii Analog inputs :- --------------------------

iv Analog outputs :- --------------------------

3.7 Power supply module :- --------------------------

i Voltage :- --------------------------

ii Frequency :- --------------------------

iii Converters :- --------------------------

3.8 Programming Language :- --------------------------




WORK AND OPERATING STATION

Sr No Description Offered by supplier

1 Manufacturer /Type :- ---------------------------

2 Number of CPU :- ---------------------------

3 CPU Details :- ---------------------------

4 RAM Capacity :- ---------------------------

5 Hard Disc capacity :- ---------------------------

6 Operating system :- ---------------------------

7 Video display unit :- ---------------------------

a Number :- ---------------------------

b Display screen :- ---------------------------

c Key board :- ---------------------------

d Printer :- ---------------------------




SECTION – X

TECHNICAL SPECIFICATION FOR LAVT CUBICLE, NGCUBICLE AND ISOLATOR




SECTION NO. XTECHNICAL SPECIFICATION FOR LAVT CUBICAL,NG CUBICAL,

GENERATOR EXTENDED TERMINALS

I N D E X

SR.

NO.

Description PAGE

NO.

10.1

10.2

10.3

Scope

Codes and Standards

Removable and Shorting Links.

Data sheets

314

316

317

318




SECTION- X

TECHNICAL SPECIFICATION FOR LAVT CUBICLE, N.G CUBICLE AND

ISOLATOR CUBICLE

10.1 SCOPE :-

The scope of these specifications shall cover the design, manufacture,

assembly, testing at manufacturer’s works before despatch, supply,

delivery, supervision, onsite erection, testing and commissioning of:-

1) LAVT CUBICLE

One set of lightning arrestor and voltage transformer cubicle of sheet

steel construction shall be supplied complete with fluorescent lamp,

internal wiring, space heater etc. The equipment details are as under:-

1 set 11000/ √3/110/ √3V/110/ √3V PT

Core-1, 100 VA, Cl 0.2

Core-2, 200 VA, Cl 3P

1 set 11000/ √3/110/ √3V/110/ √3V PT

Core-1, 100 VA, Cl 0.2

Core-2, 200 VA, Cl 3P

1 Set of 12 KV, 10 KA lightning Arrestor

1 Set of 12 KV, Surge Capacitor

3 Nos. MCB

2) N.G. CUBICLE

One set of NG cubicle of sheet construction complete with space

heater, marshalling box, illumination lamp etc. The cubicle shall havefollowing :

1 No. Disconnecting link

1 No. 11/3 KV/220 V single phase NG transformer

1 No. secondary loading resistor.




Galvanised steel supports, shorting bar etc.

3) BUS DUCT

A) 1000 A, 11 kV, segregated phase busduct for the inter connection

between Generator terminals and LAVT cubicle.

Following taps shall be provided

a) Tap for Excitation Transformer

b) End terminals for interconnection of LAVT cubicle with Isolator

cubicle.

B) Segregated phase busduct for generator neutral connection to NG

cubicle.

Phase busduct comprises of 3.2 thick Aluminium alloy enclosure and

Aluminium alloy conductor in box formation shall be provided.

4) CURRENT TRANSFORMERS :-

Following CTs shall be provided on Generator phase side .

a) Current Transformer 1000/5A

30 VA CL 5P 20 for Generator Diff. Protection

b) Current Transformer 1000/5A

30 VA CL 5P 20 for Transformer Diff. Protection

c) Current Transformer 1000/5A

30 V.A .0.2 for AVR

d) Current Transformer 1000/5A

30 V.A CL 5P 20 for other protection relays.

Following CTs shall be provided on Generator Neutral side.

e) Current Transformer 1000/5a

30 VA CL 5P 20 for Generator Diff. Protection

d) Current Transformer 1000/5A

30 V.A CL 5P 20 for overall Diff. protection .

Note:- The power transformer is not in the scope of supply of this contact.

Also synchronising is proposed to be at 220 kV switchyard supplier

for following aspects.

a) CT specification on 220 kV side for Overall Diffi Protection.

b) Control and power cable termination




c) Coordination regarding exchange of information regarding status of

220 kV breakers, breaker closing and opening command from SCADA

system etc.

d) UAT is not in the scope of this contact. Diff .protection of UAT is

included in the scope of this contact .Main plant supplier shall co-

ordinate with other supplier in respect of exchange of information

regarding CT specification requirement ,control and power cable

termination etc.

5) ISOLATOR CUBICLE :- For the purpose of keeping main power

transformer in charged condition during major shutdown of power

plant ,a motor operated isolator cubicle with 1000 A current carrying

capacity shall be provided . A tap for connection of 11 KV XLPE

cable between isolator cubicle and power transformer shall be

provided .It shall possible to operate the isolator from USB . To

avoid operation of isolator during operation of the main plant . Lock

and key arrangement shall be provided for push buttons . The isolator

contacts shall be taken in the auto plant operation sequence

programme such that at all times isolator shall be in closed position

before starting the machine.

10.2 CODES AND STANDARDS

All Equipment shall be designed ,manufactured and tested in

accordance with standards mentioned as below :-

CURRENT TRANSFORMERS

15) IEC 185/1987 Current Transformer

16) IS- 2705 Current Transformer

VOLTAGE TRANSFORMERS

17 ) IEC-186/1987 Voltage Transformer

SURGE PROTECTION CAPACITOR

18 ) IS-3070 Lighting Arrestors

19) VDE-0657 Capacitors




GENERATOR NEUTRAL EARTHING

20) IS-3151 Earthing Transformer

NOTE :-

IS – Indian Standard

IEC - International Electro technical Commission

VDE –Verband Deutscher Eletrotechniker

10.3 REMOVEBLE AND SHORTING LINKS

10.3.1 SCOPE

The scope of this specifications shall cover the design ,manufacture,

assembly and testing at manufacturer’s works before dispatch, supply

delivery ,supervision .on –site erection ,testing and commissioning of :-

- 1 set of three phase removable links to be provided in the main run to

facilitate disconnection of generator and step up transformer during testing

, commissioning and maintenance.

- 1 set of three phase removable links to be provided for tap run to unit

auxiliary transformer (UAT) to facilitate disconnection of CTs. And UAT

during testing , commissioning and maintenance.

- 1 set of three phase removable links to be provided for tap run to exitation

transformer (ET) to facilitate disconnection of CT;s ,VT-1.VT-2 and ET

during testing , commissioning and maintenance.

- 1 set of removable links in the run of neutral bus duct for segregation of

generator phase from neutral point.

- One (1) three phase set of bolted type main run shorting links for the

purpose of drying out of generator stator before commissioning or for

carrying out sustained short-circuit tests shall be provided.




DATA SHEETS

CURRENT TRANSFORMER

MAIN RUN

Sr. No. Description

1 Manufacturer / type :- ……………………………2 Rated Primary Current (A) :- ………………………

3 Rated Secondary Current (A) :- ………………………

4 Rated Secondary Output :

i) Measuring (1) :- ………………..............VA

ii) Protection (2) :- …………………...........VA

iii) Protection (3) :- ……………..................VA

iv) Protection (4) :- …………….................VA

5 Accuracy Class

i) Measuring (1) :- ………………..............VAii) Protection (2) :- …………………...........VA


iv) Protection (4) :- …………….................VA

6 Instrument security factor :- ……………………………

7 Accuracy limit factor for Protection

core

:- ……………………………

8 Short time current rating

i) Thermal current (Ith) :- ……………………………KA

ii) Dynamic current (Idyn.) :- ……………………………KA

iii) Short circuit duration :- ……………………………Sec

9 One minute Power Frequency

withstand Voltage (between

bus-bars and secondary

windings)

:- ……………………………KV

10 Inter turn insulation of

secondary winding :

- one minute across complete

winding

:- ……………………………KV

- one minute between the sections

:- ……………………………KV

11 Temperature rise of winding :- ………………………….K




CURRENT TRANSFORMER

TAP OFF RUN TO EXCITATION TRANSFORMER

Sr. No. Description Offered by supplier

1 Manufacturer / type :- ……………………………

2 Rated Primary Current (A) :- ………………………3 Rated Secondary Current (A) :- ………………………


i) Measuring (1) :- ………………..............VA

ii) Protection (2) :- …………………...........VA

5 Accuracy Class

i) Measuring (1) :- ………………..............VA

ii) Protection (2) :- …………………...........VA

6 Instrument security factor :- ……………………………

7 Accuracy limit factor for Protectioncore

:- ……………………………




iii) Short circuit duration :- ……………………………s


withstand Voltage (between

bus-bars and secondary

windings)

:- ……………………………KV


secondary winding :


winding

:- ……………………………KV


:- ……………………………KV





CURRENT TRANSFORMER

NEUTRAL TERMINAL


1 Manufacturer / type :- ……………………………

2 Rated Primary Current (A) :- ………………………3 Rated Secondary Current (A) :- ………………………


ii) Protection (1) :- …………………...........VA


iv) Protection (3) :- …………….................VA

5 Accuracy Class

ii) Protection (1) :- …………………...........VA


iv) Protection (3) :- …………….................VA6 Instrument security factor :- ……………………………

7 Accuracy limit factor for Protection

core

:- ……………………………




iii) Short circuit duration :- ……………………………s


withstand Voltage (betweenbus-bars and secondary

windings)

:- ……………………………KV


secondary winding :


winding

:- ……………………………KV


:- ……………………………KV





VOLTAGE TRANSFORMERS

VT-1 & VT-2


1 Manufacturer /type :- …………………………….

2 Primary Rated Voltage (kV) :- ………………………KV rms3 Secondary Rated Voltage

- core 1 (measuring) :- ……………………………V

- core 2 (Protection) :- ……………………………V

4 Accuracy Class

- core 1 (measuring)

- core 2 (Protection)

5 Rated Burden

- core 1 (measuring) :- ……………………………VA

- core 2 (Protection) :- ……………………………VA6 Thermal Burden

- core 1 (measuring) :- ……………………………VA

- core 2 (Protection) :- ……………………………VA

7 Voltage Factor

- Continuous service :- …………………………….

- During 8 hours :- …………………………….

- During 4 hours :- …………………………….

8 Short-circuit current

(guaranteed for secondary

windings.)




SURGE PROTECTION CAPACITORS AND LIGHTING ARRESTERS


A Surge Protection Capacitors 1 Manufacturer / type :- ………………………

2 Max. Voltage for equipment (kV) :- ……………………… KV

3 Rated voltage :- ………………… KV

4 Rated capacitance :- ……………………microfarad

4 Dielectric :- ………………………

5 Temperature class :- ………………………

6 Insulators creepage distance min :- ……………………… mm/kV

B Lighting Arresters1 Manufacturer/ type :- ……………………………

2 Rated Voltage (kV) :- ……………………………KV

3 Number of stacks




GENERATOR NEUTRAL EARTHING


A LOADING RESISTOR

1 Manufacturer / type :- ………………………2 Max. system voltage for equipment

(Um)

:- ……………………… KV

3 Rated current (A), 10 s. :- ………………… A

4 Overload capacity

i) 1s. (A) :- ………………… A

ii) 2s. (A) :- ………………… A

iii) 5s. (A) :- ………………… A

5 Resistance t = 20º C :- ………………… ohm

6 Test Voltagei) one minute 50 Hz (kVrms) :- …………..………(kVrms)

ii) Impulse 1.2/50 microsecond

(kVcr)

:- …………..……… V

B Neutral voltage transformer

or neutral point grounding

transformer

1 Manufacturer /type

2 Year VT or power transformer iscommercialised

3 Primary Voltage :- …………..……… KV

4 Secondary Voltage :- …………..……… V

5 Burden :- …………..……… VA

6 Class :- …………..………

7 One minute 50 Hz test voltage :- …………..……… KV rms

8 Impulse test voltage 1.2/50 micro

second

:- …………..………




BUSDUCT

DESIGNATION : OFFERED BY

BY SUPPLIER

Technical Particulars:-

1) Name of manufacturer :-

2) Rated voltage :-

3) Continuous current ratingat rated voltage :-

4) Type :-

5) Reference standard :-

6) Symmetrical short

Circuit rating :-

7) One minute power

Frequency with-stand :-

8) Impulse level (1.2/50)

Micro sec ;_

9) Frequency :-

10) Enclosure-a) shape

b) Material :-

11) Conductor material :-

12) Support Insulator :-

13) Ambient Insulator :-

14) Temperature rise of

enclosure above ambient :-

15) Temperature rise of Conductor above ambient :-

16) Finish of bus duct :-

17) Finish of cubicles :-




SECTION – XI

PROTECTIVE GEAR




SECTION NO. XI

PROTECTIVE GEAR

I N D E X

SR.

NO.

Description PAGE

NO.11.1

11.2

11.3

Scope

Requirement

Data sheets.

327

327

330




SECTION- XI

PROTECTIVE GEAR11.1 Scope:-

For the protection of Turbine Generator set, Excitation Transformer,

Main Transformer, unit auxiliary transformer microprocessor based

Protection Relay scheme shall be provided.

11.2 Requirement :-

1) protection scheme shall consist of main protection scheme and backup

Protection scheme.

2) Protection scheme shall consist of

a) Protection panel to accommodate all protection equipments.

b) Power supply unit: - Two power supply unit shall be used in each

protection scheme (main and backup) changeover between the

power supply unit shall be automatic.

c) Input module: - it shall consist of transformer module, relay

module etc.

d) CPU module with storage.

e) O /P relay module.

f) Software

g) LCD console to load software and setting the parameters.

h) Interfacing cables.

3) LED Indication of each protection shall be provided on panel.

4) Master trip relay with hand reset shall be provided.

5) Protection CTs on 220 KV side, UAT differential protection CTs, 220

KV Generator circuit breaker are not in the scope of this contract. TheProtection relay supplier shall co-ordinate with 220 KV equipment

supplier and other contractors for following coordination aspects.

a) Step up transformer differential protection :-

CT specification on 220 KV side & cable termination.




b) Overall differential protection :-

CT specification on 220 KV side & cable termination.

c) UAT differential protection:-

CT specification & cable termination.

11.3 Following protection shall be covered by protection system.

1) Generator Differential Protection.

2) Overall Differential Protection.

3) Step-up transformer differential protection.

4) Generator Stator Earth- fault protection.

5) Generator-Rotor Earth- fault protection.

6) Voltage controlled over- current protection.

7) Loss of excitation (Minimum reactance protection)

8) Reverse power protection.

9) Under-impedance protection.

10 ) Thermal over-load protection.

11) Negative sequence phase current protection.

12) Restricted earth-fault protection for star- connected

secondary Winding of step-up transformer.13) Over-frequency protection.

14) Under-frequency protection.

15) Generator over-voltage protection.

16) Generator under –voltage protection

17) Step-up transformer over-current protection.

18) Step-up transformer over-fluxing protection.

19) Excitation transformer differential protection.

20) Unit auxiliary transformer differential protection.

21) Any other protection required.





(To be filled in by Bidder.)

Item Description of departure. Reference to clause in the specifications




DATA SHEET

1 Name of Manufacturer :- -------------------------------

2 Type Designation :- -------------------------------

3 Size of panel :- -------------------------------

4 No of input analog modules :- -------------------------------

5 No of analog inputs per module :- -------------------------------

6 No of input digital modules :- -------------------------------

7 No of digital inputs per module :- -------------------------------

8 No of output relay module :- -------------------------------

9 No of outputs per modules :- -------------------------------

10 No of power supply module

( Details shall be furnished )

:- -------------------------------

11 No of CPU modules :- -------------------------------

12 List of protection function provided(separate list shall be furnished )

:- -------------------------------

14 Whether Master trip relay is provided :- -------------------------------




15 Will the operating console be supplied :- -------------------------------

16 Operating language :- -------------------------------

17 Operating voltage :- -------------------------------

power plant sec

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