A

Training report

On

“HEAVY FABRICATION” At

BHEL HARIDWAR

Submitted in partial fulfillment of requirements for the degree of

Bachelor of Technology In

Mechanical Engineering

Submitted By: Submitted To: UDIT SONI MOHD.YUNUS SHEIKH

B.Tech. (Final Year) Sr. Lecturer

Department of Mechanical EngineeringGOVT. ENGINEERING COLLEGE, BIKANER

RAJASTHAN TECHNICAL UNIVERSITY, KOTA2012-13

[i]

ACKNOWLEDGEMENT

“Inspiration and motivation have always played a key role in the success of anyventure.”

Success in such comprehensive report can’t be achieved single handed. It isthe team effort that sail the ship to the coast. So I would like to express my sincerethanks to my mentor MR. PARMANAND PANDIT Sir.

I am also grateful to the management of Bharat Heavy Electrical limited

(BHEL), Haridwar for permitting me to have training during June 2th to July 2th, 2012.

It gives me in immense pleasure to express my gratitude to the department of

Mechanical Engineering for their prudent response in course of completing my

training report. I am highly indebted to, MR. MOHD. YOUNIS SHEIKH, their

guidance and whole hearted inspiration; it has been of greatest help in bringing out the

work in the present shape. The direction, advice, discussion and constant

encouragement given by them has been so help full in completing the work

successfully

[ii]

INDEX

S.R. NO. TOPIC PAGE NO.

INTRODUCTION 1

1. BHEL 2 – 17

1.1.OVERVIEW 2

1.2.WORKING AREAS 3

1.2.1 POWER GENERATION 3

1.2.2 POWER TRANSMISSION &DISTRIBUTION 3

1.2.3 INDUSTRIES 4

1.2.4 TRANSPORTATION 5

1.2.5 TELECOMMUNICATION 5

1.2.6 RENEWABLE ENERGY 5

1.2.7 INTERNATIONAL OPERATIONS 6

1.3 TECHNOLOGY UP GRADATION ANDRESEARCH AND DEVELOPMENT

7

1.3.1HUMAN RESOURCE DEVELOPMENT

INSTITUTE

7

1.4 HEALTH, SAFETY AND ENVIRONMENTMANAGEMENT

8

1.4.1 ENVIRONMENTAL POLICY 8

1.4.2 OCCUPATIONAL HEALTH AND SAFETY POLICY 8

1.4.3 PRINCIPLES OF THE "GLOBAL COMPACT" 9

1.5 BHEL UNITS 11

1.6 BHEL HARIDWAR 13

1.6.1LOCATION 13

1.6.2ADDRESS 13

1.6.3 AREA 13

1.6.4 UNITS 14

[iii]

1.6.5 HEEP PRODUCT PROFILE 16

2. HEAVY FABRICATION 18 – 19

2.1 DEFINATION 18

2.2 PROCESSES 18

2.3 APPLICATIONS 18

2.4 RAW MATERIAL 18

3. METAL CUTTING 20 – 22

3.1SHEARING MACHINE 20

3.2 PLASMA CUTTING 21

3.3 OXY-FUEL CUTTING 22

4. BENDING 23 – 25

4.1 HYDRAULIC PRESS 23

4.2 ROLLING MACHINE 24

5. WELDING 26 – 29

5.1 TIG WELDING 26

5.2 MIG WELDING 27

5.2.1. CARBON DIOXIDE WELDING 28

5.3 GOUGING 28

6. INSPECTION 30 – 31

6.1 VISUAL INSPECTION 30

6.2 RADIOGRAPHY 30

6.3 PENETRATE TEST 30

6.4 ULTRASONIC FAULT DETECTOR 30

7. MACHINING 32 – 37

7.1 VERTICAL BORING MACHINE 32

7.2 PLANER MACHINE 33

7.3 MANIPULATOR MACHINE 34

[iv]

7.3.1PURPOSE 34

7.3.2 SPECIFICATIONS 34

7.4 COPY MILLING MACHINE 35

7.5 CENTRAL LATHE WITH THREE & FOUR JAWS 36

8. SHOT BLASTING 38 – 39

8.1 PURPOSE 38

8.2 SCOPE 38

8.3 SHOT DIRECTION 38

8.4 SETTING PARAMETER 38

9. BLOCK DESCRIPTION 40 – 42

9.1 PREPARATION, BAY-1 41

9.2 ASSEMBLY & WELDING SECTION,BAY-2 41

9.3 BAY -3 41

9.4 BAY- 4 41

10. MANUFACTURING PROCESSES 43 – 45

11. CONCLUSION 46

[v]

FIGURE INDEX

S.R.NO. FIGURE PAGE NO.

1 PROCESSES PERFORMED IN HEAVY FABRICATION 19

2 CNC SHEARING MACHINE 20

3 CNC PLASMA CUTTING MACHINE 22

4 CNC BACK PRESS MACHINE 24

5 THREE ROLL BENDING MACHINE 25

6 TIG WELDING 27

7 MIG WELDING 27

8 CO2 WELDING MACHINE 28

9 GOUGING CARBON ELECTRODE 29

10 DEFECT DETECTED BY ULTRA SONIC FAULTDETECTOR

31

11 VERTICAL BORING MACHINE 32

12 PLANNER MACHINE 34

13 MANIPULATOR HOLDING GBC (GUIDE BLADECARRIER)

35

14 COPY MILLING MACHINE 36

15 LATHE MACHINE 37

16 SHOT BLASTING MACHINE 39

[vi]

TABLE INDEX

S.NO. TABLE PAGE NO.

1. BHEL UNITS 12

2. HEEP BLOCKS 14

3. CFFP SECTIONS 15

4. SPECIFICATION OF THREE ROLL BENDING MACHINE 25

5. BLOCK 2 LAYOUT 40

1

INTRODUCTION

BHEL is the largest engineering and manufacturing enterprise in India in the

energy related infrastructure sector today. BHEL was established more than 40 years ago

when its first plant was setup in Bhopal ushering in the indigenous Heavy Electrical

Equipment Industry in India a dream which has been more than realized with a well

recognized track record of performance it has been earning profits continuously since

1971-72.

BHEL caters to core sectors of the Indian Economy viz., Power Generation's &

Transmission, Industry, Transportation, Telecommunication, Renewable Energy,

Defense, etc. The wide network of BHEL's 14 manufacturing division, four power Sector

regional centers, over 150 project sites, eight service centers and 18 regional offices,

enables the Company to promptly serve its customers and provide them with suitable

products, systems and services – efficiently and at competitive prices. BHEL has already

attained ISO 9000 certification for quality management, and ISO 14001 certification for

environment management.

The company’s inherent potential coupled with its strong performance make this

one of the “NAVRATNAS”, which is supported by the government in their endeavor to

become future global players.

2

1. BHEL

1.1. OVERVIEW

Bharat Heavy Electricals Limited (B.H.E.L.) is the largest engineering and

manufacturing enterprise in India. BHEL caters to core sectors of the Indian

Economy viz., Power Generation's & Transmission, Industry, Transportation,

Telecommunication, Renewable Energy, Defense and many more.

Established in 1960s under the Indo-Soviet Agreements of 1959 and 1960 in the

area of Scientific, Technical and Industrial Cooperation.

BHEL has its setup spread all over India namely New Delhi, Gurgaon, Haridwar,

Rudrapur, Jhansi, Bhopal, Hyderabad, Jagdishpur, Tiruchirapalli, Bangalore and

many more.

Over 65% of power generated in India comes from BHEL-supplied equipment.

Overall it has installed power equipment for over 90,000 MW.

BHEL's Investment in R&D is amongst the largest in the corporate sector in

India. Net Profit of the company in the year 2011-2012 was recorded as 6868

crore having a high of 21.2% in comparison to last year.

BHEL has already attained ISO 9000 certification for quality management, and

ISO 14001 certification for environment management.

It is one of India's nine largest Public Sector Undertakings or PSUs, known as the

“NAVRATNAS” or 'the nine jewels' .

The power plant equipment manufactured by BHEL is based on contemporary

technology comparable to the best in the world

The wide network of BHEL's 14 manufacturing divisions, four Power Sector

regional centre, over 100 project sites, eight service centre and 18 regional

offices, enables the Company to promptly serve its customers and provide them

with suitable products, systems and services – efficiently

3

1.2. WORKING AREAS

1.2.1. POWER GENERATION

Power generation sector comprises thermal, gas, hydro and nuclear power plant

business as of 31.03.2001, BHEL supplied sets account for nearly 64737 MW or 65% of

the total installed capacity of 99,146 MW in the country, as against nil till 1969-70.

BHEL has proven turnkey capabilities for executing power projects from concept

to commissioning, it possesses the technology and capability to produce thermal sets with

super critical parameters up to 1000 MW unit rating and gas turbine generator sets of up

to 240 MW unit rating. Co-generation and combined-cycle plants have been introduced

to achieve higher plant efficiencies. to make efficient use of the high-ash-content coal

available in India, BHEL supplies circulating fluidized bed combustion boilers to both

thermal and combined cycle power plants.

The company manufactures 235 MW nuclear turbine generator sets and has

commenced production of 500 MW nuclear turbine generator sets.

Custom made hydro sets of Francis, Pelton and Kaplan types for different head

discharge combination are also engineering and manufactured by BHEL.

In all, orders for more than 700 utility sets of thermal, hydro, gas and nuclear have

been placed on the Company as on date. The power plant equipment manufactured by

BHEL is based on contemporary technology comparable to the best in the world and is

also internationally competitive.

The Company has proven expertise in Plant Performance Improvement through

renovation modernization and upgrading of a variety of power plant equipment besides

specialized know how of residual life assessment, health diagnostics and life extension of

plants.

1.2.2. POWER TRANSMISSION & DISTRIBUTION (T & D)

BHEL offer wide ranging products and systems for T & D applications. Products

manufactured include power transformers, instrument transformers, dry type

4

transformers, series – and stunt reactor, capacitor tanks, vacuum – and SF circuit breakers

gas insulated switch gears and insulators.

A strong engineering base enables the Company to undertake turnkey delivery of

electric substances up to 400 kV level series compensation systems (for increasing power

transfer capacity of transmission lines and improving system stability and voltage

regulation), shunt compensation systems (for power factor and voltage improvement) and

HVDC systems (for economic transfer of bulk power). BHEL has indigenously

developed the state-of-the-art controlled shunt reactor (for reactive power management

on long transmission lines). Presently a 400 kV Facts (Flexible AC Transmission System)

project under execution.

1.2.3. INDUSTRIES

BHEL is a major contributor of equipment and systems to industries. Cement,

sugar, fertilizer, refineries, petrochemicals, paper, oil and gas, metallurgical and other

process industries lines and improving system stability and voltage regulation, shunt

compensation systems (for power factor and voltage improvement) and HVDC systems

(for economic transfer of bulk power) BHEL has indigenously developed the state-of-the-

art controlled shunt reactor (for reactive power management on long transmission lines).

Presently a 400 kV FACTS (Flexible AC Transmission System) projects is under

execution. The range of system & equipment supplied includes: captive power plants, co-

generation plants DG power plants, industrial steam turbines, industrial boilers and

auxiliaries. Water heat recovery boilers, gas turbines, heat exchangers and pressure

vessels, centrifugal compressors, electrical machines, pumps, valves, seamless steel

tubes, electrostatic precipitators, fabric filters, reactors, fluidized bed combustion boilers,

chemical recovery boilers and process controls.

The Company is a major producer of large-size thruster devices. It also supplies

digital distributed control systems for process industries, and control & instrumentation

systems for power plant and industrial applications. BHEL is the only company in India

with the capability to make simulators for power plants, defense and other applications.

5

The Company has commenced manufacture of large desalination plants to help

augment the supply of drinking water to people.

1.2.4. TRANSPORTATION

BHEL is involved in the development design, engineering, marketing, production,

installation, maintenance and after-sales service of Rolling Stock and traction propulsion

systems. In the area of rolling stock, BHEL manufactures electric locomotives up to 5000

HP, diesel-electric locomotives from 350 HP to 3100 HP, both for mainline and shunting

duly applications. BHEL is also producing rolling stock for special applications viz.,

overhead equipment cars, Special well wagons, Rail-cum-road vehicle etc., Besides

traction propulsion systems for in-house use, BHEL manufactures traction propulsion

systems for other rolling stock producers of electric locomotives, diesel-electric

locomotives, electrical multiple units and metro cars. The electric and diesel traction

equipment on India Railways are largely powered by electrical propulsion systems

produced by BHEL. The company also undertakes retooling and overhauling of rolling

stock in the area of urban transportation systems. BHEL is geared up to turnkey

execution of electric trolley bus systems, light rail systems etc. BHEL is also diversifying

in the area of port handing equipment and pipelines transportation system.

1.2.5. TELECOMMUNICATION

BHEL also caters to Telecommunication sector by way of small, medium and

large switching systems.

1.2.6. RENEWABLE ENERGY

Technologies that can be offered by BHEL for exploiting non-conventional and

renewable sources of energy include: wind electric generators, solar photovoltaic

systems, solar lanterns and battery-powered road vehicles. The Company has taken up

R&D efforts for development of multi-junction amorphous silicon solar cells and fuel

based systems.

6

1.2.7. INTERNATIONAL OPERATIONS

BHEL has, over the years, established its references in around 60 countries of the

world, ranging for the United States in the west to New Zealand in the far east. these

references encompass almost the entire product range of BHEL, covering turnkey power

projects of thermal, hydro and gas-based types, substation projects, rehabilitation

projects, besides a wide variety of products, like transformers, insulators, switchgears,

heat exchangers, castings and forgings, valves, well-head equipment, centrifugal

compressors, photo-voltaic equipment etc. apart from over 1110mw of boiler capacity

contributed in Malaysia, and execution of four prestigious power projects in Oman, some

of the other major successes achieved by the company have been in Australia, Saudi

Arabia, Libya, Greece, Cyprus, Malta, Egypt, Bangladesh, Azerbaijan, Sri Lanka, Iraq

etc.

The company has been successful in meeting demanding customer's requirements

in terms of complexity of the works as well as technological, quality and other

requirements viz. extended warrantees, associated O&M, financing packages etc. BHEL

has proved its capability to undertake projects on fast-track basis. The company has been

successful in meeting varying needs of the industry, be it captive power plants, utility

power generation or for the oil sector requirements. Executing of overseas projects has

also provided BHEL the experience of working with world renowned consulting

organizations and inspection agencies.

In addition to demonstrated capability to undertake turnkey projects on its own,

BHEL possesses the requisite flexibility to interface and complement with international

companies for large projects by supplying complementary equipment and meeting their

production needs for intermediate as well as finished products.

The success in the area of rehabilitation and life extension of power projects has

established BHEL as a comparable alternative to the original equipment manufacturers

(OEM’S) for such plants.

7

1.3. TECHNOLOGY UPGRADATION AND RESEARCH & DEVELOPMENT

To remain competitive and meet customers' expectations, BHEL lays great

emphasis on the continuous up gradation of products and related technologies, and

development of new products. The Company has upgraded its products to contemporary

levels through continuous in house efforts as well as through acquisition of new

technologies from leading engineering organizations of the world.

The Corporate R&D Division at Hyderabad, spread over a 140 acre complex,

leads BHEL's research efforts in a number of areas of importance to BHEL's product

range. Research and product development centers at each of the manufacturing divisions

play a complementary role.

BHEL's Investment in R&D is amongst the largest in the corporate sector in

India. Products developed in-house during the last five years contributed about 8.6% to

the revenues in 2000-2001.

BHEL has introduced, in the recent past, several state-of-the-art products

developed in-house: low-NOx oil / gas burners, circulating fluidized bed combustion

boilers, high-efficiency Pelton hydro turbines, petroleum depot automation systems, 36

kV gas-insulated sub-stations, etc. The Company has also transferred a few technologies

developed in-house to other Indian companies for commercialization.

Some of the on-going development & demonstration projects include: Smart wall

blowing system for cleaning boiler soot deposits, and micro-controller based governor for

diesel-electric locomotives. The company is also engaged in research in futuristic areas,

such as application of super conducting materials in power generations and industry, and

fuel cells for distributed, environment-friendly power generation.

1.3.1 HUMAN RESOURCE DEVELOPMENT INSTITUTE

The most prized asset of BHEL is its employees. The Human Resource

Development Institute and other HRD centers of the Company help in not only keeping

their skills updated and finely honed but also in adding new skills, whenever required.

Continuous training and retraining, positive, a positive work culture and participative

8

style of management, have engendered development of a committed and motivated work

force leading to enhanced productivity and higher levels of quality.

1.4. HEALTH, SAFETY AND ENVIRONMENT MANAGEMENT

BHEL, as an integral part of business performance and in its endeavor of

becoming a world-class organization and sharing the growing global concern on issues

related to Environment. Occupational Health and Safety, is committed to protecting

Environment in and around its own establishment, and to providing safe and healthy

working environment to all its employees. For fulfilling these obligations, Corporate

Policies have been formulated as:

1.4.1. ENVIRONMENTAL POLICY

Compliance with applicable Environmental Legislation/Regulation;

Continual Improvement in Environment Management Systems to protect our

natural environment and Control Pollution;

Promotion of activities for conservation of resources by Environmental

Management;

Enhancement of Environmental awareness amongst employees, customers and

suppliers. BHEL will also assist and co-operate with the concerned Government

Agencies and Regulatory Bodies engaged in environmental activities, offering the

Company's capabilities is this field.

1.4.2. OCCUPATIONAL HEALTH AND SAFETY POLICY

Compliance with applicable Legislation and Regulations;

Setting objectives and targets to eliminate/control/minimize risks due to

Occupational and Safety Hazards;

Appropriate structured training of employees on Occupational Health and Safety

(OH&S) aspects;

9

Formulation and maintenance of OH&S Management programmes for continual

improvement;

Periodic review of OH&S Management System to ensure its continuing

suitability, adequacy and effectiveness;

Communication of OH&S Policy to all employees and interested parties.

The major units of BHEL have already acquired ISO 14001 Environmental

Management System Certification, and other units are in advanced stages of acquiring the

same. Action plan has been prepared to acquire OHSAS 18001 Occupational Health and

Safety Management System certification for all BHEL units.

In pursuit of these Policy requirements, BHEL will continuously strive to improve

work particles in the light of advances made in technology and new understandings in

Occupational Health, Safety and Environmental Science. Participation in the "Global

Compact" of the United Nations.

The "Global Compact" is a partnership between the United Nations, the business

community, international labor and NGOs. It provides a forum for them to work together

and improve corporate practices through co-operation rather than confrontation.

BHEL has joined the "Global Compact" of United Nations and has committed to

support it and the set of core values enshrined in its nine principles:

1.4.3. PRINCIPLES OF THE "GLOBAL COMPACT"

HUMAN RIGHTS

1. Business should support and respect the protection of internationally proclaimed

human rights; and

2. Make sure they are not complicit in human rights abuses.

10

LABOUR STANDARDS

3. Business should uphold the freedom of association and the effective recognition

of the right to collective bargaining;

4. The elimination of all form of forces and compulsory labor.

5. The effective abolition of child labor, and

6. Eliminate discrimination.

ENVIRONMENT

7. Businesses should support a precautionary approach to environmental challenges;

8. Undertake initiatives to promote greater environmental responsibility and

9. Encourage the development and diffusion of environmentally friendly

technologies.

By joining the "Global Compact", BHEL would get a unique opportunity of networking

with corporate and sharing experience relating to social responsibility on global basis.

11

1.5. BHEL UNITS

UNIT TYPE PRODUCT

1. Bhopal Heavy Electrical Plant Steam turbines , Turbo generators , Hydro

sets , Switch gear controllers

2. Haridwar

HEEP

CFFP

Heavy Electrical

Equipment Plant

Central Foundry Forge

Plant

Hydro turbines , Steam turbines, Gas

turbine, Turbo generators, Heavy castings

and forging. Control panels, Light aircrafts,

Electrical machines

3.Hyderabad

HPEP Heavy Power Equipment

Plant

Industrial turbo – sets, Compressors Pumps

and heaters, Bow mills, Heat exchangers oil

rings, Gas turbines , Switch gears, Power

generating set

4.Tiruchi

HPBP

SSTP

High Pressure Boiling

Plant

Steam less steel tubes, Spiral fin welded

tubes.

5.Jhansi

TP Transformer PlantTransformers, Diesel shunt less AC locos

and AC EMU

12

6.Banglore

EDN

EPD

Control Equipment

Division

Electro Porcelain Division

Energy meters, Water meters, Control

equipment, Capacitors, Photovoltaic panels,

Simulator, Telecommunication system,

Other advanced micro processor based

control system. Insulator and bushing,

Ceramic liners.

7.Ranipet

BAP Boiler Auxiliaries PlantElectrostatic precipitator, Air pre-heater,

Fans, Wind electric generators, Desalination

plants.

8.Goindwal Industrial Valves Plant Industrial valves and Fabrication

9.Jagdishpur

IP Insulator Plant. High tension ceramic, Insulation Plates and

bushings

10.Rudrapur Component Fabrication

Plant

Windmill, Solar water heating system

11.Gurgoan Amorphous Silicon Solar

Cell Plant.

Solar Photovoltaic Cells, Solar lanterns

chargers ,

Solar clocks

TABLE 1

13

1.6. BHEL HARIDWAR

1.6.1. LOCATION

It is situated in the foot hills of Shivalik range in Haridwar. The main

administrative building is at a distance of about 8 km from Haridwar.

1.6.2. ADDRESS

Bharat Heavy Electrical Limited (BHEL)

Ranipur, Haridwar

PIN:- 249403

1.6.3. AREA

BHEL Haridwar consists of two manufacturing units, namely Heavy Electrical

Equipment Plant (HEEP) and Central Foundry Forge Plant (CFFP), having area

HEEP area:- 8.45 sq km

CFFP area:- 1.0 sq km

The Heavy Electricals Equipment Plant (HEEP) located in Haridwar, is one of the

major manufacturing plants of BHEL. The core business of HEEP includes design and

manufacture of large steam and gas turbines, turbo generators, hydro turbines and

generators, large AC/DC motors and so on.

Central Foundry Forge Plant (CFFP) is engaged in manufacture of Steel Castings:

Up to 50 Tons per Piece Wt & Steel Forgings: Up to 55 Tons per Piece Wt.

1.6.4. UNITS

There are two units in BHEL Haridwar as followed:

1) Heavy Electrical Equipment Plant (HEEP) and another

2) Central Foundry Forge Plant (CFFP).

14

THERE ARE 8 BLOCKS IN HEEP

BLOCKS WORK PERFORMED IN THE BLOCK

I. Electrical Machine Turbo generator, generator exciter , motor (ac and dc)

II. Fabrication Large size fabricated assemblies or components

III. Turbine & Auxiliary Steam ,hydro ,gas turbines, turbine blade , special tooling

IV. Feeder Winding of Turbo ,hydro generators ,insulation for ac & dc

motors

V. Fabrication Fabricated parts of steam turbine, water boxes, storage tank,

hydro turbine parts

VI. Fabrication

Stamping and die

manufacturing

Fabricated oil tanks, hollow guide blades, Rings, stator frames

and rotor spindle, all dies, stamping for generators and motors

15

VII. Wood working Wooden packing, spacers.

VIII. Heaters & coolers LP heaters, ejectors, glands, steam and oil coolers,

Oil tank, bearing covers

TABLE 2

THERE ARE 3 SECTIONS IN CFFP

SECTIONS WORK PERFORMED IN THE SECTION

I. Foundry Casting of turbine rotor, casing and Francis runner

II. Forging Forging of small rotor parts

III. Machine shop Turning, boring, parting off, drilling etc.

TABLE 3

16

1.6.5. HEEP PRODUCT PROFILE

1. THERMAL SETS:

Steam turbines and generators up to 500 MW capacity for utility and combined

cycle applications

Capability to manufacture up to 1000 MW unit cycle.

2. GAS TURBINES:

Gas turbines for industry and utility application; range-3 to 200 MW (ISO).

Gas turbines based co-generation and combined cycle system.

3. HYDRO SETS:

Custom– built conventional hydro turbine of Kaplan, Francis and Pelton with

matching generators up to 250 MW unit size.

Pump turbines with matching motor-generators.

Mini / micro hydro sets.

Spherical butterfly and rotary valves and auxiliaries for hydro station.

4. EQUIPMENT FOR NUCLEAR POWER PLANTS:

Turbines and generators up to 500MW unit size.

Steam generator up to 500MW unit size.

Re-heaters / separators.

Heat exchangers and pressure vessels.

5. ELECTRICAL MACHINES:

DC general purpose and rolling mill machines from 100 to 19000KW suitable for

operation on voltage up to 1200V. These are provided with STDP, totally

enclosed and duct ventilated enclosures.

DC auxiliary mill motors.

17

6. CONTROL PANEL:

Control panel for voltage up to 400KW and control desks for generating stations

and EMV sub–stations.

7. CASTING AND FORGINGS:

Sophisticated heavy casting and forging of creep resistant alloy steels, stainless

steel and other grades of alloy meeting stringent international specifications.

8. DEFENCE:

Naval guns with collaboration of Italy.

18

2. HEAVY FABRICATION

2.1. DEFINATION:-

Fabrication as an industrial term refers to building metal structures by cutting,

bending and assembling. The cutting part of fabrication is done via sawing, shearing, or

chisel machine (all with manual and powered machine variants); torching with handheld

torches (such as oxy-fuel torches or plasma torches); and via CNC cutters (using a laser,

torch, or water jet). The bending is done via hammering (manual or powered) or via press

brake and similar tools. The assembling (joining of the pieces) is via welding and binding

with adhesives, riveting, threaded fasteners, or even yet more bending in the form of a

crimped seam. Structural metal and sheet metal are the usual starting materials for

fabrication, along with the welding wire, flux, and fasteners that will join the cut pieces.

As with other manufacturing processes, both human labor and automation are commonly

used. The product resulting from (the process of) fabrication may be called a fabrication.

2.2. PROCESS:-

Processes involved in Fabrication are:-

Cutting & Burning.

Forming

Machining.

Welding.

2.3. APPLICATIONS:-

Equipment for Industrial Applications.

Equipment for Specialty Gases Applications.

2.4. RAW MATERIAL

Standard raw materials used by metal fabricators are:-

Plate metal

Formed and expanded metal

19

Tube stock

Square stock

Sectional metals ( I beams, W beams, C-channel )

Welding wire

Castings

Fittings

FIG.1 PROCESSES PERFORMED IN HEAVY FABRICATION

20

3. METAL CUTTING

3.1. SHEARING MACHINE:-

A shearing machine is hydraulic machine used to cut metal work-pieces with help of

Shearing mechanism. In this machine the metal work-piece are passed through the

machine through roller transmitters called guides which moves too-and fro and then

stopped with help brake stops which works hydraulically which operates by pressing foot

pedal provided at the foot of machine setup. These stops hold the work-piece tightly so

that it doesn’t disturb due to high impact of shearing cutters. Then valve is operated

which causes the fluid to pressurize and further moving the cutter down which strikes the

work-piece and causing cutting action of work-piece. Metals that can be cut are mild

steel, stainless steel etc. Maximum thickness that can be cut is 10mm. Main component

of Shearing machine is as follow:-

a) Jack:-support the plate or metal parts which are to be cut.

b) Blade:-cutting the metal parts (cutter).

c) Guide:-Numerical controlled length adjustment.

d) Hydraulic Oil tank.

FIG.2 CNC SHEARING MACHINE

21

3.2 PLASMA CUTTING:-

Plasma cutting is a process that is used to cut steel and other metals (or sometimes

other materials) using a plasma torch. In this process, an inert gas (in some units,

compressed air) is blown at high speed out of a nozzle; at the same time an electrical arc

is formed through that gas from the nozzle to the surface being cut, turning some of that

gas to plasma. The plasma is sufficiently hot to melt the metal being cut and moves

sufficiently fast to blow molten metal away from the cut.

Plasma cutters have also been used in CNC machinery. Manufacturers build

CNC cutting tables, some with the cutter built in to the table. The idea behind CNC tables

is to allow a computer to control the torch head making clean sharp cuts. Modern CNC

plasma equipment is capable of multi-axis cutting of thick material, allowing

opportunities for complex welding seams on CNC welding equipment that is not possible

otherwise. Welding torch used has outer torch made up of brass and inner one made of

copper. Minimum gap between torch and work-piece is 5mm.

This machine can be used to cut the work-piece of mild steel and stainless steel.

The differences between the cutting methods for both of these metals are the use of

nozzles & the pressure of gases applied to pass through nozzles so that cutting action is

done easily. Work-piece of thickness 100mm to 210mm can be cut from this type

machine. For e.g. For a mild steel job of thickness 100mm the cutting speed is

131.55mm/min.

Gases used in this type of machine are oxygen and Bharat Metal Cutting Gas

(BMCG). Oxy-acetylene is avoided due to less purity& heavier as compared to BMCG. It

is less pure which causes repeated cleaning of burner.

The gap between Nozzle & plate is 5mm. If gap is increased sensor adjust the

pressure according to it. Large diameter Nozzle is used for thick metal sheet & higher

pressure and vice versa for thin metal sheet.

22

FIG.3 CNC PLASMA CUTTING MACHINE

3.3. OXY-FUEL CUTTING:-

Oxy-fuel cutting is the most widely applied process for cutting mild steels and

low alloyed steels. The process covers the entire thickness range from 1 mm to 2500 mm

(0.04-100 inches), it gives an excellent cut quality and the investment costs are low.

Furthermore the process can easily be mechanized. Oxy-fuel cutting is a combustion

process. An oxygen jet burns the metal in a narrow section to make a cut and removes the

combustion products (slag) from the kerfs. The purity of the cutting oxygen is of great

importance for the cutting speed that can be achieved. A higher purity level means a

higher cutting speed. Oxy-fuel cutting are processes that use fuel gases and oxygen to

either weld or cut metals.

In Oxy-fuel cutting, a cutting torch is used to heat up ferrous metal to kindling

temperature (about 980°C). A stream of pure oxygen is trained on the hot metal which

chemically combines with the iron which then flows out of the cut, or kerfs, as an iron-

oxide slag. There have been examples of oxy-hydrogen cutting sets with small (scuba

sized) gas cylinders worn on the user's back in a backpack harness, for rescue work.

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4. BENDING

Bending is a process by which metal can be deformed by plastically deforming

the material and changing its shape. The material is stressed beyond the yield strength but

below the ultimate tensile strength. The surface area of the material does not change

much. Bending usually refers to deformation about one axis.

4.1. HYDRAULIC PRESS:-

A hydraulic press is a hydraulic mechanism for applying a large lifting or

compressive force. It is the hydraulic equivalent of a mechanical lever, and is also known

as a Bramah press after the inventor, Joseph Bramah. Hydraulic presses are the most

commonly-used and efficient form of modern press.

The hydraulic press depends on Pascal's principle: the pressure throughout closed

system is constant. At one end of the system is a piston with a small cross-sectional area

driven by a lever to increase the force. Small-diameter tubing leads to the other end of the

system. A fluid, such as oil, is displaced when either piston is pushed inward.

The small piston, for a given distance of movement, displaces a smaller amount

of volume than the large piston, which is proportional to the ratio of areas of the heads of

the pistons. Therefore, the small piston must be moved a large distance to get the large

piston to move significantly. The distance the large piston will move is the distance that

the small piston is moved divided by the ratio of the areas of the heads of the pistons.

There were two hydraulic presses at present which are:

CNC Back Press-340 ton.

Manually operated- 400 ton, 800 ton.

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FIG.4 CNC BACK PRESS MACHINE

4.2. ROLLING MACHINE:-

THREE ROLL BENDING MACHINE: Roll benders use three rolls (typically) to bend

solids, extrusions and tube and pipe to various diameters by adjusting one or two rolls.

The pyramid style roll benders have one moving roll, usually the top roll. Double pinch

type roll benders have two adjustable rolls, usually the bottom rolls, and a fixed top roll.

Large arcs, circles and spirals are typical applications for roll benders.

The roll bending machine in BHEL has following specifications:-

S.R.NO. SPECIFICATIONS DIMENSIONS

1. MAXIMUM WORKING LENGTH 8000 MM

2. MINIMUM DIAMETER OF FORMING 1300 MM

3. PLATE THICKNESS 32 MM

4. UPPER ROLL DIAMETER 7550 MM

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5. LOWER ROLL DIAMETER 680 MM

6. SPEED OF FORMING 5 M/MINUTE

7. SPEED OF LOWERING UPPER ROLL 60 MM/MINUTE

8. SPEED OF RAISING UPPER ROLL 120 MM/MINUTE

TABLE 4- SPECIFICATION OF THREE ROLL BENDING MACHINE

FIG.5 THREE ROLL BENDING MACHINE

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5. WELDING

Welding section is the most important section of this block as all the main parts of

Steam Turbine from generator to casing or from shafts to blades requires welding to join

their surfaces. Mainly the welding methods used are Shielded Metal Arc Welding (MIG),

Carbon Di-oxide welding (MIG welding) and TIG welding etc.

Air Products' shielding gases are commonly used in several welding processes,

mostly MIG and TIG welding. The selection of a suitable welding gas is essential for the

welding process. The welding gas not only protects the weld metal from the surrounding

air, it can also contribute to higher productivity and to better mechanical properties of the

weld. Air Products offers a full range of standard shielding gas mixtures for MIG welding

for all common material types.

5.1. TIG WELDING:-

TIG welding is a high-quality welding technique with a low fusion rate. The arc

burns between a tungsten electrode and the work piece; the electrode does not melt, so it

acts only as a current conductor and arc carrier.

The shielding gases protect the weld area from atmospheric gases, such as

oxygen, nitrogen, carbon dioxide, and water vapor. Depending on the materials being

welded, these atmospheric gases can reduce the quality of the weld or make the welding

process more difficult to use.

In this type of welding, tungsten electrode is used which is non-consumable. Filler

material used is either copper wire or wire of same material to be weld. When current

through tungsten electrode is passed, than a spark is produced, which is of a very high

intensity. Along with above a blow of argon gas is passed through holder to provide inert

atmosphere at welding.

The strength of TIG welding is more than any other type of welding. The

temperature of flame is varied by adjusting voltage/ current as per requirement. This type

of welding is used mainly for welding pipes. Defects occur mainly in this type of

Welding is porosity caused by stopping the flow of argon gas.

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FIG.6 TIG WELDING

5.2. MIG WELDING:-

In MIG welding, the metal electrode is used to produce spark. The current is

allowed to flow through filler metal which passes through welding holder & a blow of

gases is passed through holes provided on holder which provide safeguard to welding

area from atmospheric gases. Voltage can be adjusted according the speed of filler

material, feeding is adjusted as per requirement.

FIG.7 MIG WELDING

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5.2.1. CARBON DIOXIDE WELDING:- In this type of welding, copper coated wire is

made in contact with metal to be weld and then high current is allowed to flow through

wire which causes spark of very high intensity. Then carbon dioxide & argon gas is

blown to welding area which helps in maintaining the inert atmosphere nearby welding

area and free from oxygen. Composition of carbon dioxide & argon gas is 80:20(%).

Temperature is maintained at 3600 to 4000 ºC.

The strength of Welding with CO2-gas welding is much better as compared to

metal Arc. So for mass production and high productivity with greater quality this welding

method is used. Main defect of carbon dioxide welding is porosity.

FIG.8 CO2 WELDING MACHINE

5.3. GOUGING:-

Thermal gouging is an essential part of welding fabrication. Used for rapid

removal of unwanted metal, the material is locally heated and molten metal ejected

usually by blowing it away. Normal oxygen fuel gas or arc processes can be used to

produce rapid melting and metal removal.

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Manual metal arc Gouging is a process in which a process a electrical arc is

generated to melt the material. Other techniques like special electrodes or a jet of

compressed air are used to blow away the molten material. No specific high purity or

compressed gases are needed in these processes.

FIG.9 GOUGING CARBON ELECTRODE

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6. INSPECTION

Usually in BHEL Nondestructive testing (NDT) is performed. It is defined as

comprising those test methods which are used to examine an object, material or system

without impairing its future usefulness. The term is generally applied to non medical

investigations of material integrity. The main NDT processes at the fabrication block are

as follows:-

6.1. VISUAL INSPECTION

It is the simplest, cheapest and most widely used method amongst the entire

NDT’s. A simple visual test reveals gross surface defects easily and quickly.

However for detection of final defects, device/equipments having high degree of

precision and illumination are required.

6.2. RADIOGRAPHY

In this test the X-rays and gamma rays are used to detect deep seated internal

defects. The short wavelengths of X-ray permitted to penetrate through the

opaque material. Gamma rays are the electro-magnetic radiations that are emitted

from an unstable nucleus.

6.3. PENETRATE TESTING

Penetrate solution is applied to the surface of a pre-cleaned component. The liquid

is pulled into surface-breaking defects by capillary action. A developer is applied

to pull the trapped penetrate back to the surface where it is spread out and forms

an indication. The indication is much easier to see than the actual defect.

6.4. ULTRASONIC FAULT DETECTOR

In this process job is painted with oil and then high frequency sound waves is

passed through the job. Then the echo is recorded on detector. If the echo is

recorded with disturbance earlier than the other end then the job is defective.

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FIG.10 DEFECT DETECTED BY ULTRA SONIC FAULT DETECTOR

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7. MACHINING

Machining can be defined as the process of removing material from a work piece

in the form of chips .The term metal cutting is used when the material is metallic. Most

machining has very low set-up cost compared to forming, molding, and casting

processes. However, machining is much more expensive for high volumes. Machining is

necessary where tight tolerances on dimensions and finishes are required.

7.1. VERTICAL BORING MACHINE

In this machine there is one Ram Head On Cross Rail, Jaw Chucks, and

Automatic Lifting & Lowering of Cross Rail. There is Lubrication System on all Sliding

Ways to avoid frictional losses. A Centralized Control Station with Interlocked Electrical

Control Pane is provided. A Set of Service tools is also provided. Some Special

Accessories are also provided with this machine like as follows:-

a) Additional Ram Head On Cross Rail.

b) Turret Head On Cross Rail.

c) Threading Head On Cross Rail.

d) Side Ram Head.

e) Slotting Attachment On Cross Rail

FIG.11 VERTICAL BORING MACHINE

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7.2. PLANNER MACHINE

A planner is a type of metal working machine tool that is analogous to a shaper,

but larger, and with the entire work piece moving beneath the cutter, instead of the cutter

moving above a stationary work piece. The work table is moved back and forth on the

bed beneath the cutting head either by mechanical means, such as a rack and pinion gear,

or by a hydraulic cylinder. The carriage is heavy duty and long to gives balanced bearing

to the bed even at the end of the stroke. The bed is of heavy duty box type construction. It

is ribbed throughout the length and breadth giving vibration free movement under the

heaviest cut. Table is heavily ribbed and proportionally dimensioned heavy duty close

grained cast iron box type construction. It has 'v' slides matching the 'v' grooves on the

bed and is hand scrapped to give oil film lubrication. Cross slide has a box type

construction carrying the tool slide which can be operated by hand as well as by

automatic feed. Gearbox consists of Machine Cut gears running in anti friction bearings

with oil immersed. Tool post is a cast-iron close grained construction. Tool holders

machined out of steed blocks. Uprights are Heavy duty cast iron construction bolted to

the sides of the bed .ribbed inside to avoid vibration. Operations that can be performed by

it:-

a) Vertical planning.

b) Horizontal planning.

c) Angular Planning.

d) Slot Cutting.

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FIG.12 PLANNER MACHINE

7.3. MANIPULATOR MACHINE

Parts that cannot be welded easily by ordinary welding, especially internal curved

parts are welded using manipulators. In manipulator machine parts to be welded is fixed

with the help of fixture attached to the table of the manipulator machine. Table can be

rotate through 0º-360º and tilting of table is 0º-135º

7.3.1 PURPOSE:- Metal parts which are heavier in weight and difficult to change their

position can be weld by the use of manipulator machine which can change the position of

parts according to our requirement. Guide blade carriage blade is weld by the use of

manipulator machine. Carriage or ring is mounted on the table with the help of fixture

and then guide blade carrier blade is weld to the inner ring to both side of curved surface

by tilting the table

7.3.2 MACHINE SPECIFICATION

a) Gross weight = 7600 kg.

b) Size =393*383*180 cm3.

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c) Table diameter = 3500mm (without extension), 4500mm (with

extension).

d) Rotation of table = 00 to 3600 (clockwise or anti clock)

e) Tilting of table = 00 to 1350.

f) Table rotation speed = 0.012-0.5 rpm.

FIG.13 MANIPULATOR HOLDING GBC (GUIDE BLADE CARRIER)

7.4. COPY MILLING MACHINE

This machine is designed for milling profiles or relief contours (three-dimensional

milling) on articles made of various materials by means of a cutting tool (milling cutter),

which reproduces on the article the surface or contour of a master device—for example, a

master cam in the shape of a flat template, a three-dimensional model, or a contour

drawing. The master device is mechanically, pneumatically, or hydraulically connected to

a servomechanism, which directs the cutting tool.

36

The servomechanism acts on an amplifying device on the one hand and, on the

other hand, on an actuating device. Hydraulic, electromagnetic, or electro-optical relays

are used in the amplifying devices of such machines. The actuating member may be a

screw, a slide valve, an electromagnetic coupling, a solenoid, a differential, or some other

device, and it may be driven by an electric motor or a hydraulic power cylinder.

FIG.14 COPY MILLING MACHINE

7.5 CENTRE LATHE WITH THREE AND FOUR JAWS:

A metal lathe is generic description for a rigid machine tool designed to remove

material from a work piece, through the action of a cutting tool. They were originally

designed to machine metals; however, with the advent of plastics and other materials, and

with their inherent versatility, they are used in a wide range of applications, and a broad

range of materials.

A center lathe is a dual head machine where the work remains fixed and the heads

move towards the work piece and machine a center drill hole into each end. The resulting

37

work piece may then be used "between centers" in another operation. The usage of the

term metal lathe may also be considered somewhat outdated these days, plastics and other

composite materials are in wide use and with appropriate modifications, the same

principles and techniques may be applied to their machining as that used for metal.

A center lathe or engine lathe may be considered the basis for the metal lathe and

is the type most often used by the general machinist or hobbyist. The center lathe may be

considered a useful starting point. The engine lathe is the name applied to a traditional

20th century lathe. It is assumed that the 'engine' was added to the description to separate

them from the 'foot lathes' (lathes turned by pedals) or other hand rotated pieces of

machinery. Early engine lathes were generally 'cone heads', in that the spindle usually

had attached to it a multi-step pulley designed to accept a flat belt.

FIG.15 LATHE MACHINE

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8. SHOT BLASTING

8.1. PURPOSE

Used for hardening the root of the low pressure rotor turbine blade in fatigue load.

Shot blasting is carried out to introduce compressive stress to depth of blade. In blades,

fatigue strength and improvement in resistance to stress omission is checked along with

corrosion removal.

Blasting process consists of bombarding exposed surface of fir tree root with

steam of hardened spherical metallic dots from robotics controlled nozzle by applied air

pressure.

8.2. SCOPE

Shot blasting of steam turbine blade roots with cast steel shots type S280 to S390

in blasting intensity of range 0.3 to 0.35.

8.3. SHOT DIRECTION

Notch radii should be blasted in average normal direction. This blasts that steel

shots have to hit the radius in perpendicular direction since blasting is most effective

under this condition. Nozzle has to be point to centre of root curve.

8.4. SETTING PARAMETER: The setting parameters for machine are:-

a) Air pressure

b) Shot size

c) Nozzle diameter

d) Shot flow

e) Distance between blasted surface and nozzle.

f) Blasting time

g) Reservoir pressure

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FIG.16 SHOT BLASTING MACHINE

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9. BLOCK DESCRIPTION

TABLE 5- BLOCK 2 LAYOUT

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9.1 PREPARATION, BAY -1

It has the following sections:

a) Marking cutting and straightening section.

b) Gas cutting section including CNC flame cutting section & CNC Plasma cutting

section.

c) Press section (400T and 800T, Brake press).

d) Shearing M/c section.

9.2 ASSEMBLY AND WELDING SECTION, BAY -2

It has the following sections:

a) Assembly and welding section for large size units up to 75 tons.

b) Heat treatment section.

c) Shot blasting and cleaning section.

9.3 BAY -3

It has the following sections:

a) Assembly and welding sections of small size units unto 10 tons

b) Pipe sections.

9.4 BAY -4

It has the following sections:

a) MACHINE SECTION: It is designed for machining parts and units during

fabrication stage. This section supplies small parts and units of Steam turbine,

generators, hydro-turbine etc. The unique machines viz. CNC multi spindle

drilling machines and Horizontal ram borer are installed to help in machining of

various components like drilling of tube plates of different types apart from

machining of big assemblies such as front wall, casing, water boxes etc.

b) DIAPHRAGM SECTION: Welded diaphragms of steam turbines are assembled,

welded and stress relieved in this section.

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c) COOLERS SECTION: In this section tubes of coolers are cut to the required

size, then turned and thereafter winding and soldering of spirals on tubes is

carried out by automatic machines. These are then assembled to form coolers

which are then assembled and hydraulically tested.

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10. MANUFACTURING PROCESSES

Manufacturing starts with Preparation of individual parts before assembly, in Bay -1.

a) The metal is first marked and cut by the following machines:-

- Guillotine Shearing machine for cutting and trimming steel sheets and plates up

to 25mm thick with straight contours.

- Stationary and portable Oxy-acetylene cutting machines for cutting machines

for cutting parts out of steel plates.

- A unique Flame cutting machine is used for cutting steel plates by CNC

programming.

- CNC Plasma cutting M/c for cutting S.S & higher alloys.

- Combination punch, shear and bar cutters, circular saws and bar shears are used

for cutting angles, shapes, flats and rods.

b) Straightening Rollers are used for straightening plates and large sized blanks and a

160 ton friction press for straightening small sized blanks. A roll bending machine

is used for straightening and bending rolled beams and angles.

c) Hydraulic bending press of 800 ton and 400 ton and a 250 ton friction press are

used for cold and hot bending from rolled sheets and shapes. Parts to bend are pre

heated in a 700 KW electric furnace, when ever needed.

d) Finished parts are inspected at the working place.

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After Preparation is complete the next step is Assembly and Welding in Bay -2 and 3 is

as follows:

a) Components of units are assembled and tack welded for subsequent welding as

per drawing and instructions on process cards.

b) Manual arc welding is employed in restricted and inaccessible places or where

semi-automatic or automatic welding is not possible or has not been established.

c) Semi-Automatic submerged arc welding, GTAW and Argon Carbon-dioxide

Shielded arc welding are also used for increased productivity and better quality.

All assembly work is carried out on bed plates. Small size structures are welded with

the help of manipulators. Welding of high pressure cylinders of steam turbines is carried

out after preliminary heating up to 250° C. Heat treatment is carried out in electric

furnaces of bogie hearth, bell and pit types after welding is completed. In multi layer

welding, the roots of seams are gouged and then cleaned by mechanical means.

All assembly and welding sections have connections for compressed air, oxygen &

acetylene as well Argon carbon-dioxide mixture and water for semi automatic welding.

Weld quality inspection is adopted in accordance with the relevant specifications.

Inspection of weld quality and flaw detection is carried out by means of X-ray machines,

gamma-grapy machines of cobalt and iridium isotopes and ultrasonic flaw detectors.

Pressure vessels that are boilers, heaters, condensers and coolers undergo hydraulic

tests on special test beds meant for hydraulic testing. Kerosene leakage test is also done

in case of thin walled vessels.

Process being followed in pipe section is mentioned below:

a) Pipes with diameter of 10-60 mm and 38-108 mm are cut on pipe cutting

machines and oxy-acetylene cutters.

b) Cold bending of pipes is carried out on a pipe bending machine. Bending of

carbon and alloy steel pipes of 114 mm dia. and above is performed by heating

them in electric furnaces and then by hot bending.

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c) Facing of pipes and beveling for welding is carried out on a horizontal boring

machine with portable type pipe chamfering machine.

d) For assembly and welding of pipes bed plates and manipulators are used.

e) Heat treatment of pipes is done in electric furnace mentioned earlier.

f) Surface cleaning is done manually or by shot blasting.

Pipe assemblies are dimensionally checked and quality of welds is tested by X-

ray and Gamma grapy.

Process being followed in machining section is as follows:

a) Casting, forging, rolled section and welded structures are delivered to

sections where assembly and welding are done in accordance with

specifications set forth in drawings.

b) Pre weld machining for large sized parts for steam turbines and hydro

turbines are carried out in block-3.

c) Provision is made for the application of highly productive cemented

carbide tipped cutting tools, high speed cutting with maximum utilization with

machine tool capacity and rapid section locating and clamping fixture.

Process being followed in painting section is as follows:

a) Painting materials used and painting processes adopted, conform to the

standards for tropical climates.

b) Owing to different operating conditions and decoration requirements of units

and parts of turbines and electrical machines, different processes for painting

are adopted.

c) Some components and units undergo only prime coating in the steel structure

section, with subsequent painting in the painting section of the machine and

assembly section.

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11. CONCLUSION

Gone through rigorous one month training under the guidance of capable

engineers and workers of BHEL Haridwar in Block-2 “HEAVY FABRICATION”

headed by Senior Engineer of department MR. PARMANAND PANDIT situated in

Ranipur, Haridwar, Uttarakhand.

The training was specified under the Heavy Fabrication Department. I came to

know about the basic grinding, scaling and machining processes which were shown on

heavy to medium machines. Duty lathes were planted in the same line where the

specified work was undertaken.

The training brought to my knowledge the various machining and fabrication

processes done not only in the manufacturing of cams but also in other iron casted

products.