technical details for procurement of heat exchangers...

ATTACHMENT–X: Tender no. 14000003-HD-48009

TECHNICAL DETAILS FOR PROCUREMENT OF HEAT EXCHANGERS

NOTE: DEVIATIONS, IF ANY, SHALL BE MADE ONLY WITH RESPECT TO THE FOLLOWING SPECIFICATIONS

AND SHALL CLEARLY HIGHLIGHT THE SAME BY INDICATING APPROPRIATE CLAUSE REFERRED IN

THIS DCOUMENT. NO OTHER CONSIDERATIONS/ELABORATIONS SHALL BE ENTERTAINED.

1.0 BRIEF SCOPE OF SUPPLY & WORK

1.1 This document covers the requirements for unfired Shell and Tube type Heat Exchanger’s design,

supply of materials, including internals parts, nozzles, etc. preparation & obtaining approval of

design calculations, development of fabrication drawings, fabrication, inspection, testing, cleaning,

painting, workmanship, guarantee, packing and forwarding, along with spares and documentation,

as applicable, duly complete in all respects and ready to install and use.

1.2 Intent of this document is to supplement, amend or limit the reference codes &standards

mentioned herein.

1.3 Exceptions or variations shown in the job specifications take precedence over requirements shown

herein.

1.4 No variations from the job specifications and this specification are permitted unless specified by

the Supplier and approved in writing by HPCL.

1.5 In case of any conflict between the various specifications and codes, the matter shall be referred to

HPCL for clarifications and the clarifications provided by HPCL shall be final and binding on the

Supplier.

1.6 Preparations for shipment & transportation of the Equipment to HPCL, Mumbai Refinery, are

inclusive. Supplier to provide necessary manpower and suitable lifting devices like Winch, Hoist,

Sling, etc. as required for unloading of the equipment at Refinery. Only Crane/Fork-lift arrangement

will be provided by HPCL at unloading site, as per Equipment load requirement. Such service shall

be free of any charge. However, Supplier shall inform HPCL about the requirement in advance, at

least 5 days prior to scheduled receipt of the Equipment at site location.

2.0 REFERENCES – DESIGN CODES

The following codes in their latest edition, including addenda, as applicable at the time of bidding shall

form the basis for design, fabrication, inspection, testing and acceptance of Equipment. Wherever code is

applicable for the enclosed Exchanger data sheet,the same shall be considered from the following list.

2.1 TEMA standard, Class ‘R’ or as specified in drawing/data sheet

2.2 Relevant ASTM specifications

2.3 ASME Boiler and Pressure Vessel Code, Section-VIII, Division 1/2; Section-II, Part A/B/C/D; Section-

V; and Section-IX

2.4 AWS-ASME specifications for Welding Electrodes

2.5 ANSI B-16.5, Steel Pipe Flanges and Flanged Fittings and B-16.11, Forged Steel Fittings, Socket weld

and threaded (latest editions)

2.6 National, State and local laws and codes such as Indian Boiler Regulations (IBR), etc.

2.7 Expansion Joint Manufacturers Association (EJMA) standards

3.0 DESIGN

3.1 General Requirements

3.1.1 Materials are specified in the job specifications in general terms. Required materials shall conform

or be equal to the ASME specifications given in TEMA. Cast Iron shall be not be used.



3.1.2 Designer of Exchanger unit shall be responsible for furnishing Equipment that is free of over-

stressing for any loading within the specified maximum loading.

3.1.3 For Heat Exchangers falling under the purview of Indian Boiler Regulations (IBR), in addition to the

requirements specified in the specification, the Exchanger shall be designed, fabricated, inspected

and tested in accordance with the requirements of IBR. Approval of CIB of the State in which the

equipment is being manufactured as well as the State where the equipment is being installed (i.e.

Maharashtra State) shall be the responsibility of the Equipment Supplier at no extra cost.

3.1.4 Supplier shall check, as part of his responsibility, any design information issued by HPCL. Any

comment and/or reservations shall be stated at the bidding stage itself. Modifications and/or

variations which may prove necessary during the fabrication phase for ensuring full reliability and

efficiency of the Equipment and/or adjusting the design to suit the job/Equipment specification,

design codes, local regulations or to suit technical and fabrication facilities of the Supplier, shall be

responsibility and liability of the Supplier and shall in all cases be submitted in writing for

consideration & approval by HPCL.

3.1.5 Supplier shall obtain necessary approvals and have the required testing carried out by legally

qualified Organization such as CIB and also by the Inspection authorities, if any, specified by

HPCL.Unless expressly stated otherwise in the job specification or in the Purchase Order, Shell and

Tube Heat Exchangers shall be designed and made in accordance with the references (latest

editions) as specified above.

3.1.6 During design of Fixed Tube Sheet Heat Exchangers, considerations must be given to the stresses

induced at operating, alternate operating, start-up, shutdown and other upset conditions. Where

necessary, expansion joints shall be provided.

3.1.7 In general, Tube to Tube Sheet joints shall be expanded. All Tube Sheet holes and grooving in them

shall conform to TEMA and the following supplements. Grooves shall be squared, edged and

concentric. When heat treatment of Tube Sheet is required, final Tube hole sizing shall be attained

by reaming after heat treatment. Refer specification by reaming after heat treatment. Refer

Specification no. 6-15-04 for ‘Expanded Tube to Tube Sheet joints’.

3.1.8 Tube to Tube Sheet joints shall be welded for following cases:

a) Design temperature is <0oC or >350

oC.

b) Design pressure exceeding 50 kg/cm2g for all type of Exchangers.

c) When there is cladding on the Tube side face of the Tube Sheet, Channel side, Floating Head

side.

d) Where high reliability of the joints is required because of lethal substance, product quality,

hazards of inter-mixing, etc.

3.1.9 Where stated, Tube Bundles may be designed for the differential pressure given in job

specifications. Supplier shall provide visible Warning Plate adjacent to or part of Name Plate,

outlining test pressure regulations, when differential design is used.

3.1.10 Tube Sheets, for economic or other justifiable reason, may be clad or faced type.

3.1.11 Use extended, bolted type Tube Sheet for U-Tubes and stab in Bundles.

3.1.12 In case of Fixed Tube Sheet Exchangers, only thick Flexible Expansion Joint designed as per TEMA

shall be used. These shall be suitable for 500 start-up/shut down cycles and 5000 operating cycles.

At other places, light gauge Bellow type Expansion Joints as per EJMA may be used. These shall be

designed for 2000 start-up/shut down cycles and 7500 operating cycles.



The following shall also be complied with:

i) All CS Bellows/Joints (if hot formed) shall be normalized if not formed in normalizing range.

Cold formed bellows/joints shall be solution annealed.Supplier shall submit procedure for

approval.

ii) All welds shall be 100% radiographed.

iii) For SS Bellows/Joints, only low carbon stabilized grade of Steel shall be used.

iv) Supplier shall submit design calculations with details and fabrication procedure for approval.

v) All Expansion Joints/Bellows shall be provided with internal sleeve and shall have suitable

vending/draining provision.

vi) Material of Expansion Joint, Sleeve, transition piece, etc. shall be the same as that of the

Shell.

3.1.13 All Low Alloy Steel materials (C-Mo, Cr-Mo Steel groups, P3 onwards) shall meet the hardness

limitations as per Para 2.4.1 (b) on base metal, weld metal and heat affected zone.

3.1.14 Minimum Design Metal Temperature (MDMT) shall be taken as lower of 0oC or the design

temperature unless lower MDMT is specified elsewhere. The requirement shall be comply with all

the code/specification requirement for MDMT such as impact tested, heat treatment, radiography,

etc.

3.2 Vents, Drains and Other Connections

3.2.1 When Tube side fluid is Steam, a 40NB (flanged) operatingvent connection shall be provided in the

Channel Cover or Bonnet Head at high point of second pass.

3.2.2 When Shell side fluid is Steam, 40NB (flanged) Shell side operating vent connections shall be

provided as follows:

a) Horizontal units: One vent, located below centerline at the end opposite to the inlet.

b) Vertical units: Two vents required; one below horizontal centerline at the end of steam

travel and one near the top.

3.2.3 For total condensing service, provide a flanged 40 NB vent nozzle on top of Shell at end opposite to

Shell inlet. For stacked units, provide a vent nozzle in each Shell. Rating, Flange facing, etc. shall be

equal to that provided for main Shell side nozzles.

3.2.4 Provide multi-purpose (MP) connections for Pressure Gauge/Temperature Indicator/in-line

hydrotest/chemical cleaning, etc. These connections shall be 40 NB flanged with BF for nozzle size

100 NB and above. For 80 NB nozzles, the MP connection shall be 1˝, 6000# class,Socket welded

with Plug. For 50 NB nozzles, the MP connection shall be ¾˝, 6000# class,Socket welded with Plug.

Provide one connection each on one inlet and one outlet nozzle on each side of Heat Exchanger. In

addition, provide vent/drain connection 40NB, Flanges with BF on each side of the Exchanger if

Exchanger cannot be vented/drained through MP connections.

3.2.5 All flanges shall be of weld neck type.

3.2.6 Integral reinforced nozzles are required if any of the following conditions is applicable:

a) Design pressure exceeds 50 kg/cm2g

b) Design temperature is <0oC or >350

oC

c) Plate thickness exceeds 50mm or there is a limitation on 1st

and the last Baffle spacing

3.2.7 All connection shall be flanged, unless specified otherwise. Minimum nozzle size shall be 40 NB.



3.2.8 Nozzles shall be designed for external loading from connected piping. For Equipment where piping

analysis is not in Supplier’s scope, loading on nozzles shall be considered in design as 100 kg-m per

inch-dia of nozzle (moment) and 100 kg per inch-dia of nozzle (force) in each of the three

directions.

3.2.9 For other special applications such as Kettle Re-boilers, Kettle Steam Generators, Slurry handling,

HF Acid service, Hydrogen service, etc., applicable special constructional features shall be indicated

in the bid.

3.2.10 For HXS with design temperature below 0oC, all requirements of code applicable for equipment

below (–29oC) such as impact testing, heat treatment, full radiography, etc. shall be complied with.

3.2.11 All nozzles 50 mm and below shall be provided with two numbers Gussets @ 90o apart.

4.0 MATERIALS

4.1 Tubing

4.1.1 All Tubes shall be seamless and cold drawn.

4.1.2 Tube gauge/thickness specified is the required minimum wall thickness unless otherwise specified.

Generally, Tube thickness shall be as under:

CS/LAS 20 OD x 2 (min)

25 OD x 2.5 (min)

SS/HAS/ADMIRALITY 20 OD x 1.6 (min)

25 OD x 2 (min)

4.1.3 For U-Tubes, the wall thickness specified is applied to the tubing before bending. All U-Tubes shall

be formed from a continuous length of tubing, free of girth welds.

4.1.4 The minimum mean radius of U-bends shall be 2 times the OD of the Tube. Flattening at the bends

shall not exceed 10%nominal OD of straight portion Tube. Proposal may be based on the use of

heavier wall tubing for short radius U-bends when design pressure demands thicker Tube walls.

4.1.5 Tubing shall be in the fully heat treated conditions as received from the mill. Heat treatment shall

be annealed for CS & SS Tubes. Copper alloy Tubes shall be supplied in the annealed tempered

condition.

4.1.6 CS U-Tubes shall be stress relieved for the U-bend radii upto 5 times the tube diameter.

4.1.7 SS U-Tubes shall be solution annealed.

4.1.8 Product analysis of Tubes shall be carried out and reported.

4.1.9 All Tubes shall be hydrotested. In additional to hydrostatic test, each Tube of Copper and Copper

Alloy shall be Eddy Current tested as per Practice E-243 “Recommended Practice for Electro-

magnetic (Eddy Current) testing of Seamless Copper and Copper Alloy Tubes”. Eddy Current testing

shall be done in the final annealed condition.

4.2 Bolting and Flange closures

4.2.1 Supplier of the Exchanger unit shall guarantee tightness compatibility of their closure designs. This

especially pertains to closures where designer amalgamated components having different thermal

expansion properties.Stud Bolts with hexagonal Nuts shall generally conform to ASTM A193 Gr.B7

and ASTM A194 Gr.2H respectively, unless specifically mentioned in the drawings/specifications or

where the operating conditions prevent use of such materials. Stud Bolts shallbe fully

threaded.Bolt length specified is theeffective thread length. Rounded or chamfered endjoints shall



not be included when measuring length of Bolts. The test temperature for impact testing of all

Gr.L7 Bolts and Gr.4 Nuts per ASTM A320 shall be –120oF. Nuts conforming to ASTM A194 Gr.2,

Gr.2H and Gr.4 in sizes greater than ½˝shall not be machined from bar stock. Nuts conforming to

ASTM A194 Gr.4 insizes smaller than ½˝shall not be machined from cold finished bar stock. Bolts

conforming to ASTM A320 Gr.B8 shall be strain hardened.

4.2.2 For Floating Head Flanges, low hardness bolting such as SA193 Gr.B7M, SA 320 Gr.L7M, etc. shall

be used.

4.3 Gaskets

4.3.1 CAF Gaskets: CAF grade shall be selected by the Supplier, if suitable for the process fluid. Gasket

contact face shall be machined and provided with spiral orconcentric groove finish.

4.3.2 Metal jacketed Gaskets: Gaskets shall be double jacketed enclosed by two seams with Asbestos

orsuitable filling, shall have minimum total thickness of 3 mm beforecompression, with jacket

thickness of 0.4 mm (min).Jacket material shall be same as HE material except for Carbon Steel

vessel, where Jacket shall be of SS304material. Gasket contact face shall be provided with

smooth finish.

4.3.3 Spiral wound Gaskets:Metallic spirals with Asbestos or Graphite/PTFE filled Gaskets shall have

minimum total thickness of 4 mm. Each Gasket shall be provided with internal compression and

external guidering, when not available integral in flange.

4.3.4 Gaskets shall conform to the following standards:

Gasket type Standards

Compressed Asbestos 1/16˝ thick flat ring shape, dimensions as per ANSI B16.21

Double jacketed API 601 for Corrugated Jackets

Spiral wound API 601

Ring joint ANSI B16.20 (oval shape)

4.3.5 Compressed Asbestos Gaskets shall have an anti-stickrelease agent or be graphited on both sides

and havea minimum tensile strength of 200 psi across thegrain.

4.3.6 The grade of Asbestos and binders for impregnates used shall be suitable for service fluid

temperature.

4.3.7 The metal windings of Spiral wound Gaskets shall beof 18-Cr 8-Ni unless other special material

arerequired by the processfluid. For operatingtemperatures below –50oF, the centering ring shall

also be 18-Cr 8-Ni.

4.3.8 For Ring Gaskets, hardness of the Ring shall be lower than that of the Flange. Where it may

notbepossible to obtain this feature, as in the case ofvarious Alloys, selection of appropriate

material shall be resolved with HPCL.

4.3.9 Manufacturer shall furnish Gaskets forintermediate Flanges between multiple Shells, direct

connected Exchangers.

4.3.10 Copper Gaskets are not permitted when fluids contain H2S or Amines.

4.3.11 Hardness of the metal for solid or clad Gasket is not to exceed the following values:

i) Iron, Copper, Brass or other soft metals: maximum 80 Brinell

ii) SS, Monel or other hard Alloys: Brinell number as low as possible and to be minimum 15

Brinell lower than for the material of the Flange Gasket facing.

4.3.12 All Gaskets shall be made in one continuous piece all around including the pass ribs and therefore

must be cut from one sheet.



4.4 Plates

4.4.1 Carbon content of CS Boiler quality Plates shall not exceed 0.25%.

4.4.2 CSPlates to specification SA516 shall be in the normalized condition.

4.4.3 Plates having thickness 16to 50mm (both inclusive) shall be examined ultrasonically as per

ASTMA435.

4.4.4 For Plate thicknesses above 50mm, ultrasonic examination shall be carried out as per ASTMA578

and shall have acceptance standard of Level-B. Ultrasonic examination shall be done after the

specified heat treatment of Plates.

4.4.5 CS Boiler quality Plates/LASPlates above 50mm thickness shall meet the following additional

requirements:

i) Vacuum treatment as per the supplementary requirement S1 of SA 20.

ii) Charpy V-notch test as per the supplementary requirements S5 of SA20 test temperature:

Minus 26oC or lower as specified in SA 20/individual materials.

iii) Acceptance criteria: As per Table-A2.15 of SA 20.

Orientation of Test Bar: Transverse to the direction of rolling.

For material SA515 Gr.60, values for SA516 Gr.60 shall be taken.

iv) Bend test as per the supplementary requirement S14 of specification SA 20.

4.4.6 All SS Plates shall be hot rolled,annealed and pickled and shall have no.1 finish on both sides with

reference to SA480.

4.4.7 Plates representative of each heat shall be inter-granular corrosion tested as per ASTM A262

Practice E for all 300 series SS materials.

4.5 Forgings

4.5.1 Flanges shall be forged weld neck type.

4.5.2 All pressure forging for CS and LAS shall be in normalized and tempered condition.

4.5.3 Carbon content of CS Forging shall not exceed 0.25%.

4.5.4 CS Forgings above 75mm – all TubeSheet Forgings and all Forgings of other materials shall be 100%

ultrasonically tested as per ASTM A388. Acceptance standards shall be asper AM 203.2of ASME

Section-VIII Division II.

4.6 Pipes

4.6.1 All Pipes shall be seamless. Pipe sizes above 1½˝ NB shall be hot finished.

4.6.2 Dimensions & tolerances shall be in accordance with ASME B36.10 or 36.19, as applicable.

4.6.3 Carbon content of CS Pipes shall not exceed 0.25%.

4.6.4 All LAS Pipes shall be procured in normalized &tempered condition.

4.7 Cladding

4.7.1 Use of clad materials for economical and other reasons may be considered.

a) Cladding shall be integrally and continuously bonded to the base metal.

b) Cladding shall not be counted for the strength it adds to TubeSheet/other pressure parts.

c) When other parts in contact with the same fluid are specified as ‘Killed Steel’, base metal of the

clad or faced Tube Sheet/other pressure parts shall also be Killed Steel.

d) Bond between cladding and base metal shall be checked for a minimum strength 14kgf/mm2 in

shear by conducting Shear Test.



e) Clad Plates shall be ultrasonically examined from the clad surface in accordance with the

requirements of ASTM A578. Scanning shall be 100% of the Plate surface. Acceptance standards

shall be Level-B.

f) Clad Plates to meet the supplementary requirements S-7 of ASTM A578.

4.7.2 Materials for low temperature service:

a) All LTCS/CS Charpy material shall be fine grain practice. CS CharpyPlates shall be in normalized

condition.

b) All LTCS/LASmaterials shall be impact tested as per material specification. The impact li

temperature shall be lower of the minimum design. Metal temperature or test temperature

shall be as per ASME Section-II. The impact energy values shall be per ASME Section-III Division

I/Section-II, whichever is higher unless specified otherwise.

c) LTCS Forgings for all Flanges shall be to SA350 Gr.LF2.

4.8 SS Materials

4.8.1 SS grade materials involving welding/forming during fabrication shall be of low Carbon or stabilized

grades.

4.8.2 Materials for non-pressure parts:

a) CS materials for non-pressure parts welded to pressure parts shall be of Boiler quality.

b) CS materials for non-pressure parts not welded to pressure parts shall be SA283/tested quality

or equivalent.

c) IS226 can be used upto 20mm thickness and IS2062 above 20mm thickness.

5.0 DESIGN & DRAWING APPROVAL

5.1 Drawing review/approval: Complete design of the Equipment and all fabrication drawings are to

be reviewed and approved by HPCL. After approval of HPCL, Suppliershall obtain TPI approval for

the same before proceeding for procurement of raw materials and stage-wise fabrication.

Fabricator should stand guarantee for design of the Exchanger. All as-built drawings shall be duly

certified by the TPI.

5.2 Vendor should re-check thickness of the Equipment provided in the drawing, as per code. If the

provided thickness is not sufficient as per code,Vendor shall provide the code thickness as per

calculations. Otherwise thickness provided in the drawing shall be opted for fabrication.

5.3 The supplier shall submit mechanical and thermal design calculations and fabrication drawings for

HPCL approval. The fabrication drawings shall be made to scale and show the following:

a) Overall size of the Equipment and assembly

b) Sizes, orientation and location of nozzles and saddles

c) The sketch showing Tube layout, indicating pass positions, cross Baffle cut, orientation, location

and number of by-pass sealing strips

d) Bundle layout, giving location of first and last Baffles and the Baffle spacing

e) Impingement Plate size and location

f) Bundle weight, empty weight and operating weights of the Exchanger

g) Details of parts, with part no., material specifications, quantity, size, weight, etc. including

spares

h) Testing plan, indicating the tests to be conducted on welds/materials and assemblies such as

NDT tests/Hydrotest/Pneumatic test and Destructive tests, etc.

i) Weld lines orientation and location with weld profiles and sizes

j) Edge preparation and method employed



k) Brand name of Electrodes with equivalent AWS specifications

l) Welding procedures to be employed

m) Name plate location and details

n) Tolerances

o) Code certification and stamping requirements as indicated in the Purchase Order

p) Any other information or instructions to ensure compliance of shop procedures with code

requirements and those specifications along with the addenda

q) Purchaser’s Order number and Fabricator’s Shop Order number, Client’s name, Plant location,

Item tag no. etc.

5.4 HPCL’s review & approval of drawings shall not relieve the Supplier of his responsibilities to comply

with the applicable codes, standards & statutory regulations.

5.5 For Heat Exchangers under the purview of Indian Boiler Regulations, the Workshop drawings, after

preliminary approval of HPCL, shall be submitted to Chief Inspector of Boilers (CIB) of the State

where the Fabricator’s Shop is located. It shall be responsibility of the Supplier to incorporate

modification/additions, if required by CIB, and obtain final CIB approval. HPCL shall be kept

informed of all such changes/modifications desired by CIB. In case the Supplier’s Workshop is in a

location other than that of the State of proposed site, Fabricator shall submit the Shop drawings

simultaneously to the CIBs of the respective States. All costs involved before commissioning of the

Equipment shall be borne by the Supplier.

5.6 In case of Equipment requiring inspection by an independent authority like Lloyds, the Supplier

shall obtain necessary approval after getting the preliminary approval from HPCL at no extra cost.

5.7 The Supplier shall not proceed with fabrication of the Equipment unless the design and drawings

are approved by HPCL/Inspection Authority.

5.8 DEVIATIONS: In general, no deviations from HPCL standards and specifications shall be permitted.

This does not preclude possible innovations or improvements on the part of the Supplier based on

available facilities. Such deviations must be clearly pointed out as a separate paragraph entitled

‘DEVIATIONS’ in the Supplier’s bid, so as to avoid any confusion and ambiguity and to facilitate

analysis of quotation within the minimum possible time. It shall be taken for granted that except

for the deviations pointed out under the ‘DEVIATIONS’ paragraph, all other technical requirements

are adhered to by the Supplier. No deviations shall be incorporated, unless it has been approved in

writing by HPCL. It is in Supplier’s interest to get the written approval of HPCL for all deviations

before accepting the Purchase Order. No deviations shall be entertained or approved after the

Order has been accepted by the Supplier. Delay in supply of the Equipment on account of such

deviations being not entertained or approved by HPCL shall be contractor’s liability.

5.9 In case there are no deviations required by the Supplier, quotation under the ‘DEVIATIONS’

paragraph shall read as “EQUIPMENT SHALL BE SUPPLIED AS PER HPCL’S SPECIFICATIONS,

CODES,etc. IN ALL RESPECTS”. It shall be presumed that the Supplier has clearly understood the job

requirements and shall fully comply with them.

6.0 MATERIAL SUPPLY

6.1 All materials & accessories required for fabrication of the Heat Exchangers shall be supplied by the

Supplier unless otherwise stated. All materials procured from outside India shall be inspected by

reputed TPI agency cost of which shall be borne by the Supplier. Mill test certificates alone are not

final.

6.2 Name Plate: Stainless Steel Name Plate shall be provided by the Supplier on each Heat Exchanger

Shell.

6.3 Testing Devices: Test Rings andTest Flanges shall be designed and supplied by the Supplier.

Drawings for these also shall need prior approval of HPCL. The number of Test Ring/Flange

assemblies shall be equal to the number of Shells stacked.



Test Ring shall be provided for all Floating Head Exchangers with bonnet on Channel side and for

Channel with flat covers having test pressure on Tubeside greater than the Shell side. Design all

testing accessories for testing the Bundle outside the Shell for Exchangers with design pressure on

Tubeside greater than the Shell side.

All necessary arrangements such as supports, Blind Flanges, Test Gaskets, Bolts& Nuts and other

accessories shall be provided by the Supplier for testing of the Heat Exchangers.

6.4 Accessories: Supplier shall include in his quotation supply of Tie Bolts, leveling shims or

intermediate supports for stacked units, Gaskets, Nuts & Bolts relating to interconnecting nozzles

(Tube and Shell sides). All these components shall be dispatched separately with due care having

been taken regarding identification of these for ease of installation. Supplier should also include for

minor modification/additions like Ladder, Insulation Cleats, etc. which may be required at a later

stage.

6.5 Earthing Lugs: Earthing Lugs shall be provided on each Heat Exchanger which shall be located in

such a way that the same do not foul with the Exchanger foundation bolts during installation.

6.6 Torque Devices: All Torque values for tightening the Bolts shall be mentioned in fabrication

drawings of the Heat Exchangers.

6.7 Davits: If required as per design, Davits shall be provided.

6.8 It is deemed that Supplier shall supply the Equipment strictly as per the requirements of the codes,

specifications, etc. As such it is presumed that unless indicated under the ‘DEVIATIONS’ paragraph

of the quotation, dimensions and materials for various components in a Heat Exchanger are as per

HPCL’s requirement. This does not preclude use of equivalent or better materials. However, these

deviations should be clearly indicated in the quotation. If an equivalent material sought by the

Supplier is to a specificationother than IS or ASTM/ASME, it might be necessary for the Supplier to

submit the specifications of the equivalent material (translated in English language if the original is

not in English).

7.0 SPARES TO BE SUPPLIED

7.1 Supplier shall supply 20% extra Studs and Nuts, but not less than 4 Studs with 8 Nuts for each pair

of mating Flanges, interconnecting nozzles, nozzles with Blind Flanges, etc.

7.2 Supplier shall also supply 4 sets of spare Gaskets other than those used or testing and/or during

transportation.

7.3 Any other spares, tools and tackles required for 2 years operation/maintenance shall be supplied.

Supplier shall submit the details of such spares in the offer.

8.0 FABRICATION

8.1 Plate Cutting

8.1.1 Carbon and Low Alloy Steels: Carbon Steel and Low Alloy Steel Plates are to be cut to size by

flame cutting and/or machining. When Plate thickness does not exceed 25mm, cold shearing

may be used provided that the sheared edge is cut back by machining or chipping for a

distance of ¼th

of thickness of the Plate but in no case less than 3 mm. All Plate edges after

cutting shall be examined for laminations to ensure that the sheared edges are free from

cracks. Dye penetration and Ultrasonic check of edges forming main weld seams is

recommended especially for higher thickness Plates when these Plates are used for low

temperature or in Hydrogen service. For Low Alloy Steel Plates, edges of the Plates shall be

preheated before flame cutting.

8.1.2 Austenitic Steels: Austenitic SSPlates should be cut by plasma cutting. However, for

thicknesses upto 15mm, cold shearing may also be adopted. In all cases, the cut edges shall

be ground back by 2 to 3 mm and checked for laminations and cracks. It is recommended



that cut edges forming main weld seams of pressure containing parts be checked

ultrasonically or by Dye-penetration examination.

8.2 Handling of Materials

To maintain quality &finish of the materials, avoid any rusting and minimize additional cleaning

etc., following preventive measures should be taken:

a) Material should be kept in original cases or wrappers until fabrication actually begins. Cases or

wrappers may be opened for initial inspection, but after inspection these should again be

carefully packed. These should be stored indoors on clean racks, shelves or platforms and

should be suitably covered and kept free of shop dirt, pickling or plating fumes, particles or

scale from steel fabrication, lubricating oil, etc.

b) FabricatedEquipment should be cleaned of all residues before being employed for a new

operation on SS. Paper or other protective covering should be placed on all surfaces.

8.3 Rolling and Dishing of Plates

8.3.1 Rolling: Rolling of Plates shall be in longitudinal direction of the Plates. The direction shall be

clearly marked on the Plates.Re-rolling after welding is not normally recommended.

However, if for large diameter Shells, re-rolling of welded Shell course is required, this shall

be done in presence of the authorized Inspector. All welds on the section to be re-rolled

must be ground flush. After re-rolling, all the welds on the re-rolled section must be checked

by Dye penetration test. Such welds shall then be subjected to radiography as required by

drawings/codes.

8.3.2 Dishing:All dished heads shall be single piece construction and ellipsoidal in shape.

Torispherical dished heads with knuckle radius greater of 3T or 15% and crown radius 80% of

OD are also acceptable. Straight face shall be minimum 38mm or 3T, whichever is more (T

being the nominal thickness of Plate from which forming is done). Straight face in any case

need not exceed 50mm, unless specifically indicated otherwise. Dished heads shall be

subjected to dye penetration test on knuckle portions (both inside and outside) and weld

edges after heat treatment. All CS and LAS heads shall be normalized if not formed in

normalizing range. All SS dish heads shall be solution annealed after forming.

8.4 Welding

8.4.1 General: All welding procedures shall be submitted to HPCL for approval giving all relevant

details. Welding qualification records shall indicate hardness values of weld metal, HAZ and

parent metal and also results of impact tests when design temperature is 0oC or lower or

when specifically indicated for materials being welded. No welding shall be undertaken until

the welding procedure and welder’s qualifications have been approved by HPCL and/or by

the authorized inspection agency. All welding procedures and welders shall be qualified for

the particular type of welding and material in accordance with the ASME Boiler and Pressure

Vessel Code, Section-IX. Supplier shall be responsible for the quality of the welds performed.

8.4.2 Welded joints and procedures:Pressure holding butt joints shall be full penetration double

side welded butt joints. Root pass of single side welded butt joints shall be done with TIG

welding and with Argon Gas purge. This procedure shall also be followed for TubeSheet to

Shell welds in fixed TubeSheet Heat Exchanger. Backing Strips for single side welded butt

joints is not permitted. All other pressure holding welds and welds of Lugs, etc. with pressure

parts shall be full penetration and DP/MP tested.All internal welds on the Shell shall be

ground flush from inside. All other welds may be left in the descaled condition only.

However, for LTCS materials, even these shall also be ground flush or dressed smooth.



8.4.3 Staggering of weld seams: Longitudinal seams shall be staggered with a minimum

circumferential distance between the centers of welds of 5 times the thickness of thicker

Plate. Weld seams shall be so located as to avoid connections and external attachments.

8.4.4 External attachments:External attachments like lugs, supports, etc. of Carbon Steel shall not

be welded directly to high Alloy or Austenitic SS Heat Exchanger components. These

attachments should be of the same material as the Heat Exchanger component. If this is not

so, intermediate Pad Plates of the same material type as the Heat Exchanger component

may be used. These Pads shall be at least 100mm wider and longer than the attachment and

shall be at least 5 mm thick. Welding of CS to Austenitic SS shall be done with 25%-Cr12%-Ni

Electrodes (AWSE309).

8.4.5 Tube-Tube Sheet welding: Tubeto Tube Sheet welding, if specified in the Heat Exchanger

drawing, shall be carried out as per the procedure approved by HPCL. No distortion

whatsoever shall be permitted on the Gasket seating surfaces due to Tube to Tube Sheet

welding. If distorted, the same shall be machined suitably.

8.4.6 Partition Plate welding: CS and 300 series SS, except for low temperature service, all

Partition Plates shall be welded to Channels, etc. by minimum 6mm continuous fillet welds

on both sides. For all other materials and low temperature services, all Partition Plate to

Channel welds shall be full penetration. Partition Plates thicker than 10mm shall be tapered

to 10mm at partition groove, except when mentioned otherwise on drawings. One no. 6 mm

dia.weephole shall be provided at the center of each horizontal Pass Partition Plate and a

5mm radius notch on top/bottom point of each vertical pass partition plate for all multi-pass

Exchangers for effective venting and draining.

8.4.7 Welding consumables: All welding shall be done with Electrodes, Fillers and Fluxes of

reputed make, with reproducibility of results. Brand names shall be specifically approved by

HPCL. For CS pressure parts, the Electrodes shall be of low Hydrogen type.

8.4.8 Cladding shall be cut back at all seams to permit back welding of the basemetal. Weld metal

shall be ground flush and fully covered with the applicable weld deposit. The weld deposit

shall be at least as thick as the lining.

8.4.9 Cladding shall be 100% ultrasonically examined for lack of bond after forming and, if

necessary, repaired by weld overlay of the same or similar analysis. Nozzles may also be clad

by explosion bonding with the same examination as for clad heads, or tubular liners may be

used which shall be welded to the alloy facing at the flange end and to the inside flush with

the Exchanger vessel.

8.4.10All weld overlay, whether manual or automatic procedure, shall be liquid Dye penetrant

examined in accordance with the methods described in ASTME165. When the overlay

involves two passes (layers) and the procedure uses an intermediate heat treatment with

cooling to room temperature prior to applying the second layer, each layer shall be

examined. Where overlay is to be machinedsuch as in nozzles and flange facing, machined

surface shall be examined. If 100% of overlay is examined prior to the final post weld heat

treatment, the overlay shall be spot examined (no less than 10% of the surface) after heat

treatment. Spot examinations shall be conducted after shop hydrostatic testing.

8.5 Tube Sheet and Baffledrilling

Tube holes in Tube Sheets shall be drilled so as to allow not less than 0.8mm in diameter of metal

for reaming. These shall then be reamed to final size. Before the final reaming operation is done,

Supplier should check the actual OD of the Tubes for the respective Heat Exchanger. This is of

major importance in case of Austenitic SSTubes. Tube hole grooving in Tube Sheets shall be carried

out. Tube holes in Baffles and Tube Sheets shall be de-burred and cleaned before assembly. The



interior surface of the Tube holes in Tube Sheets shall have a smooth finish and be free from spiral

scratches and scores.

8.6 Cleaning of Tube Holes

After reaming operation, suitable precautions shall be taken to ensure that interior surfaces of the

Tube holes are maintained free of rust, until Tubes are inserted. Before insertion of Tubes, Tube

holes and Tube ends must be free from oil, grease, dirt and protective coatings (on Tubes as

received from mill) and other foreign matter. For this purpose,Tube ends must be thoroughly

cleaned for a distance of at least one Tube sheet thickness plus 30mm. Cleaning solution should be

chlorides free (especially for Stainless Steels) and should not lead to fire hazards. This solution may

be sprayed by an air-pressured Spray Gun.

8.7 Nozzle Flanges, Nozzles and Reinforcement Pads

8.7.1 Flanges: Unless otherwise indicated, dimensions, drilling, facing and tolerances for nozzle

Flanges (and Blind covers, if required) up to 24˝ NB shall be as per ANSI B16.5 for the

respective class. Flanges above 24˝ NB shall be as per API 605, unless indicated otherwise.

Bolt holes on these nozzle Flanges shall straddle on principal vertical and horizontal

centerlines of the Equipment. If the component to which nozzles are attached is

subsequently stress relieved, it shall be Supplier’s responsibility to maintain true Gasket

faces by machining or otherwise. If distortion expected is considerable, final machining

operation should be done after stress relieving. Sufficient matching allowance for this

purpose should be available. Nozzle Flange facings, Gaskets and bolting details for nozzles

with the piping specification and class shall be indicated on the drawing.

8.7.2 Nozzle Pipes:Nozzle Pipes shall be attached to the Heat Exchanger components by full

penetration welds. Attachment welds using only inner and outer fillet welds are not

permitted. Unless otherwise shown on the drawings, necks of all nozzles shall be flush with

the inside of the Heat Exchanger component. Inside corners of nozzle Pipes of Shell/Channel

ID shall be rounded off to 3mm radius. All nozzles 2˝NB and below shall have two nos.

Stiffeners, 30 mm wide x 6 mm thickness, placed at right angles. Pipes shall be to ANSI

B36.30 or 36.19, as applicable.

8.7.3 Reinforcement Pads and testing: Reinforcing pads, whenever required as per codes, shall be

of the same material or equivalent as the Heat Exchanger component to which it is welded.

All Reinforcement Pads shall be provided with two nos. 1/8˝ (3mm) NPT tapped holes located

180o apart for Air-Soap solution test. This test shall also be required to be carried out for slip-

on Flanges. Pressure of 1.25 kg/cm2g is suggested for these tests. Higher test pressure are

not recommended because of accompanying risks and also because the Soap bubbles have a

chance to blow off. Tell-tale holes in the Reinforcement Pads shall be plugged with heavy

Grease, unless otherwise indicated.

8.8 Bolts, Studs etc. & Tapped Holes

All inch bolting and threading shall conform to ANSI B1.1, except for size 1˝ and above where it

shall be 8 threads per inch. Metric bolting/threading shall conform to ISO261 (coarse), tolerance

medium, except for size M24 and above, where it shall have 3mm pitch. Studs shall extend beyond

the Nuts by about 10mm and shall be threaded full length. Threads on external bolting, plugs, etc.

shall be lubricated with Graphite Grease for working temperatures upto 200oC and with

Molybdenum di-sulphide for higher temperature. All Nut seating faces shall be machined or spot

faces. Tapped holes drilled on the Channel side face of clad Tube Sheets for removable Bundles

shall be fitted with Plugs of a material similar to Channel side material. Eye Bolts for these shall be

provided loose and unless otherwise indicated, shall be of CS forged. Flanged joints shall be

provided with Jack Screws and necessary Lugs as per HPCL Standard. For extended Tube Sheets,



tapped holes shall be provided for girth bolting. Studs for these shall have square ends. Nut height

shall be equal to Bolt diameter.

8.9 Assembly and Handling

8.9.1 Suitable method of alignment like Dowels, etc. shall be provided to prevent mis-assembly of

Channel, Channel Covers, Stationary Tube Sheet, etc.

8.9.2 Heat Exchangers, which are stacked in service, shall be assembled in the Workshop for a trial

fit. Special care shall be exercised in truing up connecting nozzle Flanges. Complete assembly

shall be given a hydraulic test as a single unit except when the test pressures for individual

Heat Exchangers are different.

8.9.3 In case of removable Bundles:

a) Stationery Tube Sheets shall be drilled and tapped at vertical (0o) position for attaching

Eye Bolts or a Lifting Lug of adequate thickness that shall be welded with minimum 25

mm diameter hole.

b) Drilling and tapping, as above, may be carried out on Floating Tube Sheet.

c) Last Support Plate shall be drilled (25 mm diameter) for lifting. Local stiffening may be

necessary to adequately support the Bundle.

d) Tube Bundle pulling force shall be taken as 100% of the Tube Bundle weight.

8.9.4 Adequate lifting and handling Lugs, etc. shall be provided by the Fabricator to ease handling,

lifting, erection, etc. of the complete Equipment.

8.9.5 Pulling Eye Bolts shall be provided for all removable Bundles.

8.9.6 Davits shall be provided for removal of Channel, Channel Cover, Shell Cover and Floating

Head assembly, if necessary as per design.

8.10 Descaling, Pickling, etc.

Descaling, pickling and passivation shall be done for all Stainless Steel surfaces or parts which are

subjected to high temperature (500oC and above) during forming (like U-bending of Tubes or

dishing) or welding. The Supplier shall supply details of the procedure for approval.

8.11 Fabrication Tolerances &Finish

8.11.1 Dimensional tolerances shall be within the limits indicated in standards. Where tolerances

are not specified, these shall be in accordance with the requirements of TEMA (latest

edition).

8.11.2 All edges and corners shall be de-burred (or radiused, if shown).

8.11.3 Finish of all machined components shall be minimum 12 microns (500 RMS), unless

otherwise indicated. Parts subjected to Ultrasonic examination shall have minimum finish of

6 microns.

8.11.4 Tube Sheet faces shall be flat within ± 1.5mm (camber).

8.12 For non-ferrous Heat Exchangers, paragraphs NF 7 and NF 14 of Appendix NF in part UNF of

Section-VIII Div.1 of ASME code are mandatory. This applies to non-ferrous cladding or applied

lining also.

9.0 RADIOGRAPHY AND OTHER NDT REQUIREMENTS

9.1 General

9.1.1 The minimum extent of radiography shall be spot.

9.1.2 Supplier shall allow for full radiography in case of Heat Exchangers which fall under the

following categories:



a) Exchangers under IBR

b) Where the relevant design code/specification does not permit a lower class of

construction.

9.1.3 All pressure retaining welds which are not required to be radiographic shall be subjected to

either Magnetic particle or Dye penetration check or both at the discretion of the Inspector

after root pass welding, final welding and back chipping.

9.1.4 Radiographic and other requirement for Low Alloy Steel welds shall be in the heat treated

and final condition.

9.1.5 If radiography is being substituted by UST for the final closing seam as permitted by code,

Magnetic particle inspection shall be carried out in addition to UST.

9.2 Spot Radiography

When spot radiography is asked for, it shall mean that at least 10% of the total welded length must

be radiographed.Length of each radiograph shall be atleast 250mm. Further, all ‘-‘ joints must be

radiographed and at least one shot must be taken on each longitudinal and circumferential seam.

HPCL authorized Inspector shall mark the areas to be radiographed. This requirement shall

supplement the ones specified in ASME Section-VIII Division 1.

9.3 Acceptance Standards or Radiography

Acceptance standards for radiography shall be as per ASME Section-VIII Division 1.

10.0 HEAT TREATMENT

10.1 Post Weld Heat Treatment (PWHT) shall be done when required by relevant fabrication

specification, codes, service conditions, etc. No welding or heating is permitted after PWHT

operation.In addition to code requirements, CS and LAS shall have PWHT (including Tube to

TubeSheet joint, if welded), if –

a) Under lethal service

b) Low temperature below 0oC (Tube to TubeSheet joint excluded for temperatures warmer

than specified)

c) Sour service (wet H2S)

d) Hydrogen service

e) Amine or Caustic services, etc.

f) Under IBR

g) Other services where stipulation of hardness of welds are applicable

h) Other services where stipulation of impact tests of welds are applicable

10.2 All machining operations shall be carried out after Heat Treatment. It shall be the responsibility of

the Supplier to leave sufficient allowance for this purpose.

10.3 Supplier shall submit the procedure for PWHT alongwith the fabrication drawings for HPCL’s

approval.

10.4 Contact expansion in case of welded Tube to Tube Sheet joint shall be done after PWHT.

11.0 INSPECTION & TESTING

11.1 General

Inspection shall be carried out by HPCL representative or HPCL approved TPIA appointed by the

Supplier as per the PO terms, hereinafter referred to as the authorized Inspector.The materials,

fabrication and testing of Exchangers shall be open to inspection by the authorized Inspector in



addition to any inspection required by the specified code or by local authorities having jurisdiction

over the installation.Inspection shall be carried out both during fabrication and before delivery and

also for sub-ordered materials, in any. In addition to final inspection and certification by Inspector;

during the course of manufacture, authorized Inspector’s written approval shall be obtained by the

Supplier at all stages of fabrication including:

a) Raw material identification

b) Edge preparation for welding, including visual check for laminations

c) Alignment of longitudinal and circumferential seams

d) Rolling tolerances on individual section

e) Alignment of sections and components

f) Root pass clearance before welding and cleaning

g) Thinning of dished ends and toriconical pieces after forming

h) Checking of tube sheet after drilling, including visual check for laminations

i) TubeSheet to Shell set up for fixed TubeSheet Exchangers, prior to welding operation

The presence of authorized Inspector shall not modify or reduce the obligation of the Supplier to

carry out his own tests and control. Should any material and/or Equipment be found not in

compliance with the requirements specified, the authorized Inspector or his delegate shall be

entitled to irrevocably reject them, even if such non-compliance has not been evidenced in the

course of inspection and/or tests.The authorized Inspector will, at the time of initial visit, set up

with Supplier actual details of inspection stages to be witnessed or carried out; the schedule of

further visits and subsequent inspection notices can be arranged between the Inspector and the

Supplier. Supplier shall notify the authorized Inspector sufficiently in advance on any fabricating

operations to permit him to arrive at the Vendor’s Shop in time to witness.

Prior to final inspection all slag, weld spatter, loose scale, dirt, grit, paint, grease, oil and other

foreign matters shall be removed in order to facilitate inspection. All Reinforcing Pads and Slip-on

type Flange welds shall be pressure tested with Air-Soap solution before and after heat treatment

(if any) and before final hydrostatic test.A dimensional checking of Equipment shall be carried out

taking into account the tolerances shown on HPCL standards, design specifications or applicable

codes. The more stringent values shall govern. Dimensional checks are to be taken of the internal

measurements of equipment together with external ones and these are to be recorded on a copy

of the drawings as being the “As-built” dimensions.

11.2 Hydrostatic and Other Tests

11.2.1 These tests shall be witnessed by the authorized Inspector. When hydrostatic tests are

performed, the indicating Gauge shall be connected to the uppermost part of the

Equipment. Testing water shall be Salt free. For SSEquipment and Exchangers with SS

Bellows, use De-Mineralized Water or Condensate. Final hydrostatic tests shall be carried out

using service Gaskets and the Equipment shall be dispatched in as tested condition.

Minimum metal temperature during hydrostatic tests shall be 20oC. Test pressures shall be

maintained for at least one hour.Shell and Tube sides shall be tested separately, unless

otherwise mentioned on the drawings. For TubeSheet designed for differentialpressure,

special care shall be taken during testing. Equipment drawings shall clearly indicate by a

note, if Tube Sheets have been designed for differential pressure.

11.2.2 All vertical Exchangers shall be tested in vertical position. Alternatively, test pressure may be

modified with prior HPCL approval.

11.2.3 Stacked Exchangers, with nozzles interconnected, shall by hydrotested in the stacked

condition.

11.2.4 Supplier can appoint any of the following HPCL approved TPIAgencies for the job:



a) Lloyds; b) Bureau Varitas; c) CEIL; d) DNV; e) TUV; f)Velosi; g)Bax Counsel

11.2.5 Irrespective of Third Party Inspection, HPCL will have the right to visit Vendor's premises to

ascertain quality and progress of jobs. All TPI charges shall be clearly mentioned in the offer

and payable as per the PO terms. All materials to be approved by TPI and sample to be

provided free of cost for additional testing by HPCL if required.

12.0 STAMPING AND NAME PLATES

12.1 Name Plate: Each Exchanger shall be fitted with a Name Plate as per standard.

12.2 Item/Tagnumber Stamping: The following Exchanger parts shall bear HPCLExchanger item/tag

number –Shell Girth Flanges, Shell Cover Flanges, Channel Girth Flanges, Flat Channel Cover,

Stationery and Floating TubeSheets, Floating HeadCover Flange, Floating Head Backing Ring,

connecting pieces, Test Ring, Test Flanges and other main removable parts. These parts shall be

stamped except for Heat Exchangers in low temperature service, where the item/tag number shall

be marked with non-removable ink.

13.0 DATA FOLDER

13.1 Supplier shall supply Six (6) sets of bound copies of Data Folders, containing the following

information:

a) Manufacturer’s data report (code certificate)

b) Exchanger outline drawing and part drawings corrected to show the actual dimensions ‘As-

built’ on a sheet of size boundary lines 235 x 407 mm and Paper size 279 x 432 mm

c) Certified material test report, showing location, heat numbers, chemical analysis and

physical properties of all materials used in the fabrication of the Exchangers

d) Reports of tests made on welded test plates, if any such tests are made

e) Photostat copy of the temperature recording chart obtained during heat treatment; the

cycle of heating, soaking and cooling shall be shown

f) Copies of hydrostatic and other test reports

g) Copy (rubbing) of Name Plate

h) Records of radiographic examination

i) Photostat copy of approving agency’s certificate, if any

j) Method of packaging proposed with sketch showing anchorage

k) Any other documentation, as required

13.2 Equipment shall be dispatched only after the completion of the Data Folders.

14.0 DOCUMENTATION

Vendor’s drawings should contain the following details while submission (all drawings shall be developed

on AutoCAD, latest release):

1. Common Vendor's drawing number on each drawing with no. of sheets

2. Vendor's signature for checked & approved on tracing

3. As-built stamp on each updated drawings

4. Allrelated drawing, description & reference no. to be mentioned on general arrangementdrawing

for ready reference

5. Size of the drawings should not be larger than K/A1 size

6. Furnishing allas-built drawings in the form of tracing prints

7. CD, containing soft copies of all as-built drawings – one full set of drawings in .pdf file format and

one full set in .dwg native file format prepared in AUTOCAD, latest release

8. CD, containing soft copy of the Data Folder – one full set in .pdf file format



Vendor shall submit the following documents at different stages, as described below:

P = Prints

Documents For approval Final

Design calculations 3P Data Folders *

Fabrication drawings 3P Data Folders/CD *

Stage inspection reports * 2P Data Folders

Final inspection reports * 2P Data Folders

Material test certificates * 2P Data Folders

NDT records * 2P Data Folders

Guarantee certificate - Data Folders

Notes:

1) Documents marked * thus shall be submitted duly signed & approved by Inspection-in-charge.

2) Vendor shall submit non-tearable good legible reproducible for hard copy prints.

3) The following are to be submitted within one week in Data Folder after completion of the job with

due signature & stamp for HPCL's records:

1. Guarantee certificate for the material supplied by the Vendor as per Guarantee Clause

mentioned in the PO

2. Material summery chart

3. Test certificates & Inspection reports

4. Heat Treatment chart

5. WPS (Welding Procedure Specifications)

6. PQR (Procedure Qualification Record)

7. Radiography chart/report/films

8. Hydrotest report

9. Final dimension report

10. One set ofas-built transparencies (non-tearableTechnova or equivalent film of 50 Microns)

11. CD for ‘As-built’ drawings& Data Folder soft copies

15.0 PROTECTION AND DISPATCH

15.1 General:After completion of all testing and inspection, the inside of complete equipment shall be

thoroughly drained and dried out. Equipment shall be completed dried by passing hot air for

sufficient time until no further increase in relative humidity of outgoing air is observed. Dryout shall

be done simultaneously on both Shell and Tube sides. Flange faces shall be covered by suitable rust

preventing easily removable oil and protected by temporary Steel covers. Opening shall on no

account be fitted with tapered wooden plugs for this purpose. All threaded holes shall be suitably

protected with Steel Bar Plugs.The Exchangers shall be filled with Nitrogen at 0.25 kg/cm2 pressure

and a non-return Valve provided. Write a note in bold capital letters “Equipment filled with

Nitrogen“. Exchanger shall be shipped alongwith complete packing and shipping instructions. For

imported Exchangers, the packing shall be seaworthy.

15.2 Shop painting: Painting shall be carried out as per specification given below. Vendor to use paint

from any of the HPCL’s approved manufacturers, i.e. 1. Berger Paints, 2. Shalimar Paints, 3. Asian

Paints, 4. Bombay Paints. The Equipment shall be shot/slag blast cleaned to SA 2½ surface

preparation standard and shop painted on the outside with the following specifications:

PAINTING

SCHEME

NO. OF

COATS

PAINTING SYSTEM DPT/COAT IN

MICRONS

2 Heat resistant Silicone Aluminum paint 20

TOTAL 40

No Equipment shall be released for shipment until the authorized Inspector approves it.



15.3 Equipment to be delivered to HP Fuels Refinery and to be unloaded at Project Warehouse or any

other designated area within the Refinery premises, as advised by HPCL Supervisor in-charge at the

time of unloading, with the help of HPCL Crane/Forklift assistance free of any charge. However, all

other accessories, manpower as required for unloading the Equipment at Refinery site shall be

provided by the Supplier.

15.4 CSexternal surfaces other than flanged faces and other machined surfaces shall be given one shop

coat of Primer paint. Surfaces to be painted shall be prepared for painting by removing loose mill

scale, rust, oil, grease and other films or substance harmful to the adhesion of paint. Shop coat

shall be Zinc chromate.

15.5 Identification: The Equipment Tag number, PO number and name & address of HPCL shall be

painted in bold letters written with stencil on the Heat Exchanger at visible area.

15.6 Dispatch of Equipment:Heat Exchangers shall be dispatched in as tested condition.Heat Exchangers

shall be securely anchored for dispatch in order to prevent any shifting and damage during

transportation. Expansion Joints and Bellows, wherever encountered, shall be suitably protected

against any possible damage. Packaging shall be suitable for rail or road transport and also

seaworthy, if required. Spare Gaskets and other loose spares shall be dispatched separately in a

box and marked with PO number, Equipment Tag number and name & address of HPCL.

16.0 GUARANTEE

16.1 Supplier shall guarantee that the Equipment furnished is free from fault in design, workmanship

and material and is of proper size and capacity and is of proper material to fulfill satisfactorily the

specified conditions. Should any defect in design, material or workmanship develop before or

during the Guarantee Period, the Supplier agrees to make necessary or desirable alterations,

repairs and replacements of defective Equipment free of charge and shall bear the entire

transportation and other costs involved to and from the User’s Plant. No allowance will be made

for alterations or repairs made by others without written consent or approval of Supplier. If the

defect or failure to function cannot be corrected, the Supplier agrees to replace promptly, free of

charge, the said Equipment or to remove the Equipment and refund the full purchase price. In no

case will the Supplier be responsible for contingent liability.

16.2 The Guarantee Period, unless otherwise indicated in the Tender/PO documents, shall be 12 months

from the date of commissioning or 18 months from the date of dispatch, whichever is earlier.

17.0 PATENT INFRINGEMENT

Supplier shall defend any and all infringement suits in which the owner and/or HPCL is made a defendant,

alleging patent infringement on the Equipment purchased from the Supplier. Supplier shall pay all costs

and expense incident to any such litigation. It being further agreed and understood, however, that HPCL

shall have the right to be represented therein by counsel, of their own, selection and paid by them.

Supplier shall pay all damages, profits and/or cost which may be awarded to the plaintiff in any such

litigation; and, in general, shall defend purchaser and/or HPCL against all claim or demand of every kind

to which they may be subjected under the patent laws, in connection with equipment purchased under

this specification.

18.0 DELIVERY

Delivery of the Equipment in time shall be the essence of the contract.ProposedDelivery scheduleof the

Tender is 7 months from the date of LOI placement by HPCL or6 months from the date of first level

drawing approval by HPCL, whichever is earlier.HPCL will provide comments/approval of drawings within



7 working days of submission of drawings by the Manufacturer. Any delay on HPCL part beyond the

specified 7 working days shall be compensated by adding the same on the overall delivery schedule.

Offers beyond the specified delivery schedule of overall 7 months will also be considered for evaluation

maximum up to additional 7 weeks, subject to commercial loading @ ½% per week or part thereof.Offers

beyond (7 months + 7 weeks) will be summarily rejected without further reference.

19.0 LIQUIDATED DAMAGE PENALTY CLAUSE

Liquidated damage penalty shall be deducted for delay in delivery beyond the end delivery date of the

PO, @ ½% per week or part thereof, subject to a maximum of 5% of the PO value.



Page | 20

ANNEXURE-Ito PR

DEVIATIONS FROM TEMA

1.0 Scope

This Specification outlines the requirements for materials, design, fabrication, inspection and

testing of Shell and Tube Heat Exchangers (other than Steam Surface Condensers) for Refinery

service and should be read in conjunction with the Standards of Tubular Exchanger Manufactures

Association (TEMA), latest edition.

2.0 General

2.1 The requirements given in this specification and the general specifications of Heat

Exchangers (Section-I) are mandatory, unless changes are approved in writing by HPCL.

2.2 Heat Exchanger shall generally comply with TEMA Class ‘R’, this specification, the Data

Sheet, the drawings attached and the Purchase Order.

2.3 Pressure Vessel design calculations shall be provided for all pressure parts of the Heat

Exchanger. Computer print-out sheets are acceptable subject to HPCL’s approval providing

all essential data, including calculated minimum required wall thickness (excluding corrosion

allowance) are given and clearly identified for all parts. In cases where the Exchangers are

fabricated by other than the Designer, the Designer’s calculations will be acceptable

provided they apply to the Exchanger “As-built”.

2.4 When indicated on the Data sheet, provision shall be made as required on Shell, TubeSheet,

etc. for the use of a Tube Bundle Extractor.

2.5 This specification generally follows the format of TEMA and qualifies various TEMA sections,

as noted. TEMA paragraph numbers are shown in parenthesis after subheadings.

3.0 TEMA Section-2: HEAT EXCHANGER Fabrication Tolerances

Heat Exchanger fabrication tolerances (F): The permissible out of roundness of a completed Shell

shall allow a metal template to pass completely through the Shell without binding. The templates

shall consist of two rigid Discs (each having a diameter equal to the diameter of the transverse

Baffles rigidly mounted perpendicularly on a Shaft and 12” (300 mm) apart.

4.0 TEMA Section-3: General Fabrication and Performance Information

Shop operation (G-1): Additions to (G-1) Shop operation

1. General

a) Whenever possible, full penetration double welded butt joint shall be used for

pressure containing parts.

b) All double welded butt joints shall have root pass back chipped before welding the

second side of the joint. All butt joints shall be Magnetic particle tested after back

chip.

c) If ‘Arc air’ is used for cutting or gouging, the surface of Carbon or Carbon Manganese

Steels shall be ground to a bright finish before welding.

d) ‘Arc air’ shall not be used on ferritic or austenitic Alloy Steels.

e) Each pass shall be thoroughly cleaned and checked. All defects shall be removed

before the application of subsequent passes.

f) The use of Backing Strips is not permitted where pressure containing parts are

involved. In case of structural attachments, HPCL’s approval is required.



Page | 21

g) All welding including attachments of Lugs, Stiffening Rings, structural Clips, etc. shall

be completed prior to post weld heat treatment. No welding is permitted on any

Equipment after post weld heat treatment.

h) All tacking and welding of temporary Lugs for alignment shall be done with approved

procedures, employing the same Electrode or Filler Wire specified for butt or fillet

welds of the Shell or Channel and the same preheat requirements. Such welds shall

be removed and not incorporated in the finished welds.

i) In the case of weld deposit lined Equipment, an undiluted lining of the specified

thickness is required. This will require a greater thickness of deposit.

j) All longitudinal and circumferential welds of the Shell (other than on Kettle type units)

shall be finished flush with the inner contour for ease of Bundle insertion and

withdrawal.

k) Pass Partition Plates for forged or welded Channels and Floating Heads shall be

welded full length from both sides or shall have full penetration welds.

l) All attachments welds, both internal and external, shall be by continuous fillet welds.

Intermittent welding is not permitted.

m) Removal of Shell material adjacent to nozzle connections due to distortion in welding

shall not be permitted.

n) Cold formed Flanges or Dished Heads shall be normalized or critically or sub-critically

annealed after fabrication.

o) Attention is drawn to the dimensional tolerance requirements for matching nozzles

and saddles of stacked heat exchangers. Exchangers which are to be stacked shall be

checked in the shop for nozzle and saddle match. Shims shall be tack welded in place.

2. Welding Procedures

a) Suppliershall submit his qualified procedures for approval before fabrication

commences. Procedure specifications and qualification records shall be submitted in a

form as per the code. Where Supplierproposes to use previously approved

procedures, he shall still complete the above mentioned form and provide also a copy

of the approved procedure qualification record together with laboratory report.

b) Use of welding processes other than submerged arc, manual metallic arc or Tungsten

Inert Gas requires HPCL’s approval.

3. Welder/Welding Operators

All Welders used for fabrication of the Heat Exchangers shall be qualified in accordance with

the code and shall mark their welds with their individual marks or low stress stamps.

Austenitic SS welds shall not be marked but a sketch shall be supplied showing weld seams

and welders.

4. Welding Consumables

a) All welding consumable shall be of recognizable brand approved by HPCL. For Alloy

consumable, test certificates shall be provided.

b) All welding consumable shall be capable of producing weldments having physical,

chemical and mechanical properties at least equal to those of the base metal. The

strength of the deposit weld metal shall not be substantially greater than the base

metal.

c) Where Impact testing is required for the Equipment, Manufacturer’s test certificates

showing weld metal impact properties are required.

d) Use of ferriticMolybdenum bearing Weld Rod for welding CS is prohibited unless

specifically approved by HPCL.



Page | 22

e) All welding consumable shall be stored and baked in accordance with the Electrode

Manufacturer’s recommendations.

f) The use of ‘Active Fluxes’ is prohibited.

5. Preheating

a) Preheat shall be applied per the relevant code and as specified in the welding

procedure.

b) Preheat shall be uniformly applied, measured by suitable means and maintained

throughout welding. In the case of ferriticChrome Steels containing over 2%-Cr, then

the weld shall not be allowed to cool below 400oF (205

oC), prior to final PWHT unless

an intermediate heat transfer is applied by heating to 1100 to 1150oF (600-620

oC)

holding for ¼ hour per inch of thickness, wrapping in insulation and allowing to cool.

The temperature shall be suitably monitored. Such intermediate heat treatments do

not obviate the necessity for a final heat treatment.

6. Post Weld Heat Treatment

a) PWHT shall be applied as per the relevant code and as specified in the welding

procedure.

b) A minimum holding time of 2 hours at temperature is required for ferriticAlloy Steel

components.

c) After PWHT, it may be necessary to cool slowly from the holding temperature to

obtain satisfactory hardness values as determined by the weld procedure

qualification.

7. Hardness Requirements

Weld metal must meet the following hardness requirements (after PWHT, where this is

applicable):

Material Production weld

maximumHardness

C & C-MnSteel 200 HB

1¼-Cr ½-Mo Steel 225 HB

Other Cr-Mo Steels 240 HB

5.0 Inspection (G-2)

Additions to G-2.1 Manufacturer’s Inspection

5.1 General

a) Generally, non-destructive testing (other than positive materials identification)

required by the design code or Purchase Order shall be carried out after PWHT. Final

radiography may be waived in certain instances (in agreement with HPCL) for readily

weldable Carbon Steels examined by Ultrasonic or other HPCL approved method. The

above is not intended to prevent Supplier from carrying out intermediate radiography

or Ultrasonic testing where the costs are in Supplier’s account.

b) For ferriticAlloy Steel Equipment, 2˝ (50mm) or more in thickness, four days must

elapse after completion of welding prior to non-destructive testing and before

hydrotesting.

5.2 Radiography

a) Radiography shall be in accordance with the design code except that, as minimum all

intersections involving category A, B or C welds (or their design code equivalents)



Page | 23

shall be radiographed in such a manner as to cover all relevant welder/procedure

combinations.

b) HPCL/authorized Inspector reserves right to call for supplementary inspection and

testing which may be radiographic or ultrasonic. The costs for such supplementary

testing, where required to clarify inconclusive or questionable radiographs, shall be in

Supplier’s account, else shall be in HPCL’s account.

c) Remedial work required as result of supplementary testing shall be Supplier’s

account.

d) Supplier may propose Ultrasonic testing in lieu of radiography but such substitution

requires HPCL’s approval.

5.3 Ultrasonic testing

a) All Ultrasonic Operators shall be certified to an acceptable qualification, e.g. CSWIP

3.6. Qualification shall be available on request to HPCL’s Inspector.

b) When Ultrasonic testing is required, Supplier shall submit a complete procedure,

including the following items, for HPCL’s approval:

i) The size and type of smallest flaw to be detected

ii) Method of setting sensitivities

iii) The actual test sensitivities to be used

iv) The procedures to be used

v) The surface condition

c) ASME Section VIII Division I, Category D welds or their equivalent shall be

ultrasonically tested as follows (in lieu of code radiography requirements)

i) Full radiography case - 100% of all welds

ii) Minimum radiography case - 1 weld in 4 as a minimum, but with all relevant

welder/procedure combinations being represented

iii) In the event of testing per (ii) above requires any repair of welds then all

Category D welds shall be ultrasonically examined

5.4 Dye Penetrant and Magnetic Particle Testing

a) The following items shall be Dye penetrant or Magnetic particle tested:

i) Each pass of Austenitic Stainless Steel weld deposit lining

iii) Sealing and closure welds between cladding for clad plates and strip linings

iv) Longitudinal welds and end closure welds for sleeved nozzles

v) Attachment welds of Exchanger supports, Lifting Lugs, Davit supports, etc.

vi) Nozzle neck to Shell or Channel welds

b) Cracks and defects shall be repaired and retested.

c) For Austenitic Stainless Steel and Nickel alloy,Dye Penetration testing materials shall

meet requirements of ASME Section V, Article 6, for the control of Sulphur and

Chlorine.

d) Welds shall be thoroughly cleaned after inspection.

5.5 Hardness testing

a) Hardness checks shall be carried out on each longitudinal and girth weld and on one

weld at each nozzle plus such additional welds as may be required to ensure testing of

each weld procedure.

b) Measurement checks shall be taken with a Tele-BrinellTester or other HPCL approved

Instrument.



Page | 24

5.6 Positive Material Identification

a) Deposited weld material for all alloy welding procedures shall be analyzed to ensure

that weld alloy content is at least equal to that specified for the base metal.

b) For Austenitic Stainless Steel deposit lining, analysis shall be taken below the surface

of the finished weld representing lower half of the corrosion allowance to ensure that

thickness of undiluted alloy is at least equal to the minimum corrosion allowance

specified.

c) On finished Exchangers of FerreticAlloy Steel, all pressure containing components

including all welds shall be checked to ensure that the correct material has been used.

d) On finished Exchangers with clad or lined materials, each individual piece of cladding

or lining and each weld shall be checked to ensure that the correct material has been

used.

e) Vendor shall submit for HPCL’s approval proposed methods for the checks listed in a)

through d) above

f) All Positive Material Identification on the Exchangers shall be done after fabrication and

Vendor shall submit a written statement (per Section VIII) guaranteeing that all

materials are correct.

g) Additions to G-2.2 Purchaser’s Inspection

1. HPCL reserves right to carry out partial or complete inspection of materials and

Equipment during the course of fabrication and to inspect the finished article

for compliance with the terms of the Purchase Order and specifications.

2. VENDOR shall investigate and approve all sub-suppliers and shall make available

to the Inspector full information on the status of sub-orders for materials and

progress of all fabrication. Copies of sub-orders shall be supplied immediately

after order placement. VENDOR or his representative shall inspect all sub-

orders as required to ensure compliance with specifications.

3. Hydrostatic test will be witnessed by the Inspector, unless the Vendor is

otherwise advised. Notice of such test shall be given at least 7 days in advance.

6.0 Name Plates (G-3)

Addition to G 3.1 Manufactures Name Plate

Name Plate shall be mounted so as to clear the insulation, if any.

Qualifications to G-3.1.1 Supplemental Name Plate Data

Name Plate and supplemental Name Plate data shall include the following:

i) Code to which Exchanger is designed

ii) Code to which Exchanger is fabricated, if different from i)

iii) Tubeside and Shell side hydrostatic test pressure, Tubesheet hydrostatic test pressure

(for units designed for differential pressure only)

iv) Radiography and SR performed

vi) Inspector’s Stamp

vii) Warning “Tubesheet designed only for differential pressure” wherever applicable

7.0 Drawing and ASME Code Data Reports (G-4)

New Item Information required with Proposal

Vendor shall provide with his proposal the items listed in the Tender document.

Qualification to G-4.1 Drawings for Approval and Change

Vendor shall submit drawings and data for approval in accordance with the Tender document.

Qualification to G-4.2Drawings for Record



Page | 25

Prior to release of Equipment for shipment,Vendor shall supply final drawings and data in

accordance with theTender document.

8.0 Guarantee (G-5)

Amendment to G-5.1Performance

Thermal performance and mechanical design shall be guaranteed for a period extending for

one year after the unit is commissioned or 18 months after date of delivery, whichever occurs

earlier.

9.0 Preparation of Heat Exchanger for Shipment (G-6)

Addition to G-6.1Draining

Units shall be thoroughly dried before shipment.

Addition to G-6.2Flange Protection

1. Flanges shall be covered with Wood, Plastic or Steel Plates.

2. Permanent Blind Flanges or Covers shall be bolted up with the specified Gaskets in place,

ready for service.

Substitute for G-6.3Threaded Connection Protection

1. Threaded connections outside the Exchanger shall be protected with brightly colored

Plastic thread protectors.

2. Test holes in Reinforcing Pads shall be plugged with stiff Grease only.

Additions to G-6.4Damage Protection

1. Exchangers shall be suitably prepared for shipment. One coat of standard Primer shall be

applied to the external parts of Exchanger (except Tube Bundle). Exchangers with

Austenitic Stainless Steel parts shall be left unpainted.

2. Tube Bundles shipped separately shall be appropriately crated and if of FerriticSteel

construction they shall be sealed in Plastic. HPCL’s Equipment tag number and Purchase

Order number shall be stamped on the Tube Sheets.

New Item Ancillary Equipment

All Ancillary Equipment, including Test Rings, spare Gaskets, etc. shall be securely and plainly

marked or tagged with Purchase Order number and the HPCL’s Exchanger tag number.

New Item Stacked Units

Shims are to be shipped match marked and tack welded to the Saddles. Saddles are to be

stamped with the match mark or thickness of shim to be used.

New Item Thread Lubrication

A high temperature Thread Lubricant of recognized/reputed quality shall be applied to all

Bolts, prior to installation. Thread Lubricants for Austenitic Stainless Steel bolting are subject

to HPCL’s approval.

New Item Beveled Connections

Connections that are beveled for welding shall be suitably covered to protect the bevel from

any damage.

10.0 General Construction Features of TEMA Standard Heat Exchangers (G-7)

Addition to 7.1 Supports

1. Fixed shell support and the Anchor Bolts shall be designed to withstand a longitudinal force

equal to 150% of the Bundle weight. Shear Stress supports and Bolts shall not exceed 40% of

the yield.

2. The following requirements apply to Stacked Exchangers:



Page | 26

i) Jack screws or other means shall be provided for separating units that are

flanged or connected by a spool piece.

ii) Lower Shells shall be designed to carry the superimposed load without suffering

any distortion that could cause binding of the Tube Bundles.

iii) The design shall provide for a shim allowance of approximately ¼” (6mm)

between the faces of the stacked Exchanger intermediate supports.

iv) Stresses due to differential expansion between Shells, nozzles and supports shall

be taken into account.

Addition to G-7.11 Supports - Horizontal Units

1. Elongated holes are to be provided on the support that is remote from the Channel end.

2. Exchangers shall be sloped 1:200 towards the Channel end.

3. Where Shells are fabricated from Plate, the bearing afforded by the Saddles shall extend

over at least one third of the circumference of the Shell.

Additions to G-7.2 Lifting Devices

1. Exchangers (other than small Multi-tube Hair Pin and Double Pipe Exchangers), shall be

provided with support brackets for Davits (similar to Drawing given in Section-6). If the

Unit is of floating head design these shall be provided at both ends. For stacked Units,

support brackets are required on the top Unit only.

2. Where Units are to be stacked, Lifting Lugs shall be installed on Channels, Bonnets and

Floating Head covers in accessible positions for Davit operation.

3. Lifting Lugs shall be provided on the Shell to permit removal of the complete Unit for

maintenance activities.

4. All Lifting Lugs shall be arranged so as to be clear of anticipated insulation.

New Item Attachment Welds

All Attachment welds shall be by continuous fillet welds. Intermittent welding is not

permitted.

New Item Assembly

Match marks or Dowels shall be provided to prevent mis-assembly of the following bolted

joints:

1. Multi-pass Floating Head Cover to Tube Sheet

2. Multi-pass Channel to Tube Sheet (provide positive means of ensuring correct seating of

Pass Partitions in Type B Heads)

3. Grooved Channel Cover to Channel

4. Stationary Tube Sheet to Shell

New ItemBundle Skid Bars

Skid Bars welded to the Transverse Baffles and Support Plates to form a continuous sliding

surface, or other suitable device shall be included on all removable Bundles weighing more

than 20,000 lbs (9080 kgs).

11.0 TEMA Section 5 – Mechanical Standards for TEMA Class ‘B’ Heat Exchangers

11.1 Scope and General Requirements (R-1)

Amendment to R-1.1 Construction Codes

Vessels shall comply with ASME Section VIII, Division 1, except that where the

operating temperature at any time is 32oF (0

oC) or lower, a minimum design

temperature shall be established.

Addition to R-1.2 Design Pressures



Page | 27

For stacked exchanger in series, the most severe design pressure and temperature

conditions for the respective shell and tube side shall be taken to apply to all the

respective shell and tube sides unless PURCHASER specifically agrees otherwise.

Addition to R-1.3 Testing

1. For Exchangers with Tube Sheets designed for differential pressure, hydrostatic testing

shall be in accordance with (a) and (b) below:

a) For Tubeside or Shell side tightness test, pressure test to the lesser of:

(i) 1.5 times design differential pressure or

(ii) Appropriate Tubeside or Shellside test pressure

b) For Tubeside and Shell side strength tests, pressure both Tubeside and Shell side

simultaneously to their respective strength test pressure ensuring that at no time

the differential pressure is exceed.

3. In establishing the hydrostatic test pressure, the maximum allowable working pressure

shall be taken as the design pressure.

4. No part of a Vessel shall be stressed under hydrostatic test to more than 90% of the

material specified yield strength at test temperature.

5. Hydrostatic testing shall be carried out after all post-weld heat treatment is complete.

6. The temperature of the hydrostatic test water shall not be less than 60oF (15

oC) or such

high temperature as may be specified in the Purchaser Order.

7. Test water in contact with Austenitic Stainless Steel shall contain less than 50 ppm of

chlorides.

8. Vessels shall be drained and dried after testing.

9. Pneumatic testing at 5 psig (35 kPag) with Soap suds shall be carried out on:

(i) Strip linings and nozzle sleeve liner, before hydrostatic test

(ii) Reinforcing Pads after hydrostatic test

10. Halogen (organic or inorganic) Gas testing of Austenitic Stainless Steel parts is not

permitted.

11. For replacement Tube Bundles, pressure testing of rolled joint Bundles is not required.

12. Vendor shall furnish all test materials including Blinds, Bolts and Gaskets. Gaskets used

on test shall be the same typesthat are to be shipped with the final assembly.

Addition to R-1.5 Standard Corrosion Allowances

1. Corrosion allowance shall be as specified on the Data Sheet.

New Item for R-1 Scope and General Requirements

1. Design temperature

The Shell side design temperature shall be used for the design metal temperature of the

Shell and Shell Cover, including Flanges. The Tube side design temperature shall be used

for the design metal temperature of the Channel, including Flanges and Cover. The

design temperature of Bolts and Gaskets shall be the same as that of the respective

Flanges; however the design temperature of Bolts and Gaskets for Shellto Channel joints

shall be based on the most severe case.

For Exchangers in series, consideration shall be given to the maximum or minimum

temperature on each side of each Exchanger under clean and fouled conditions.

New Item for R-2 Tube

1. Tube diameters, gauges and lengths shall be as specified on the Data Sheet.

2. The following gauges shall be considered standard for general requirements for ¾˝ Tubes

Carbon Steel: 12 BWG min wall

FerreticAlloy Steel: 12 BWG avg wall

Austenitic Stainless Steel: 14 BWG avg wall

Copper Alloys: 16 BWG min wall



Page | 28

Aluminium: 16 BWG min wall

Monel 400: 18 BWG min wall

Incoloy 801: 18 BWG min wall

Titanium: 20 BWG min wall

Gauges heavier than these may be required for severe service conditions or to prevent

buckling of bundles during handling. Due allowance must be made for thinning of U-

bends.

New Item for R-3 Shell and Shell Cover

Addition to R-3.1 Shell

1. Carbon Steel Shells shall be post weld heat treated when the Shell side is in Amine or

Caustic service, regardless of operating temperature.

Addition to R-3.2Shell Cover

1. Fabricated CSShell Covers shall be post weld heat treated when the Shell side is in Amine

or Caustic service, regardless of operating temperature.

Baffles and Support Plates (R-4)

Amendment to R 4.2 Tube holes

1. Tube hole diameter shall be based on the nominal OD of the tube.

Amendment to R 4.3 Transverse Baffle and Support clearance

1. Clearance greater than shown in TEMA Table shall not be used unless approved by HPCL.

Amendment to R 4.42 Longitudinal Baffle

1. Total thickness of the Longitudinal Baffle shall be derived from

Total metal thickness = Required thickness + one corrosion allowance

Required thickness is defined as the greatest of

i) ¼˝

ii) Transverse Baffle thickness as per TEMA R 4.41

iii) Thickness required for differential pressure derived from

iv) t= ax * √(p/s) inches, where p = calculated shell side pressure drop, Psi

and s = specified minimum yield stress

a& x are defined as follows

a x

1.0 Distance from Tubesheet from nearest Transverse Baffle

0.816 Distance between adjacent Transverse Baffles

2. Longitudinal Baffles for two pass Shells are only permitted where Shell side pressure drop

does not exceed 30 psi (200 kPag). In addition, if Lamiflex type or equivalent Seals are

used, they shall not be subjected to a temperature differential of more than 300oF

(165oC). Use of Longitudinal Baffles is subject to HPCL’s approval.

3. LamiflexSeals or equivalent shall be installed in the correct way round so that they seal

more tightly under the operating differential pressure.

Addition to R 4.56Tube Bundle vibration

1. Where Purchaser advises or Designer’s experience indicates that the possibility of Tube

Bundle vibration exists, Designer shall give consideration to reducing the maximum

unsupported Tube lengths quoted in table R 4.52, increasing Tube wall thickness and/or

diameter, reducing Tube hole clearance, etc.

Addition to R 4.61 Shell side impingement protection requirements

1. Shell side inlet impingement plates shall be provided on all Heat Exchangers.

2. Design of Shell side Impingement Plates shall be such that they can easily be relocated

when Bundle is rotated 180o.



Page | 29

3. All Shell side Impingement Plates shall be of sufficient size to prevent direct impingement

on the Tubes and shall as a minimum extend at least 1˝ (25 mm) beyond the projection

of nozzle bore.

4. Shell side Impingement Plates shall be so designed and positioned that the effective exit

area is not reduced by close proximity of Baffles, Tube Support Plates, etc.

5. Nominal thickness of the Impingement Plate shall be not less than ¼˝ (6 mm).

Additions to R 4.62 Shell or Bundle entrance and exit areas

The unrestricted flow entrance area at the Impingement Plate shall be not less than the flow

area of the inlet nozzle

Addition to R 4.8 Sealing devices

Tube Bundle design shall incorporate features to avoid by passing of the Shell side fluid as

follows, wherever applicable:

i) Where the radial clearance between the outer most Tube and the Shell exceeds half the

Tube pitch, provide Longitudinal Seal Strips (or Tie Rods with Spacers) located between

Baffle cuts. This requirement does not apply to Kettle type Re-boilers (TEMA Fig K).

ii) Where Tube rows have been omitted because of front or rear end partitions, provide

dummy Tubes (or Tie Rods with Spacers) for each 3 to 4 Tube rows where the cross flow

direction is such that by passing would occur.

iii) For U-Tube Bundles where the plane of the bends parallel to the Baffle cuts, space

between the inner most Tube rows shall be sealed by dummy Tubes (or Tie Rods with

Spacers). Provide one dummy Tube for each 3 to 4 Tube rows located in the space

between Baffle cuts.

iv) Sealing devices shall be located to minimize obstruction of mechanical cleaning lanes.

v) Seal strips shall be attached to the Transverse Baffles by continuous welds.

5.5 Floating heads

Addition to R 5.12 Post weld heat treatment

Fabricated CS Floating Head Covers need not be post weld heat treated after completion of welding

unless required by the code, specified in the PO, or when either Tube or Shell side is in Amine or

Caustic services (regardless of operating temperature).

Addition to R 5.131 Internal bolting

Internal bolting shall be in accordance with the Data sheet/PO.

Addition to R 5.21 Packed floating heads

Packed Floating Head construction shall not be used.

5.6 Gaskets

Addition to R 6.2 Gasket materials

1. Gasket materials shall be in accordance with the Data sheet/PO.

2. For high pressure/high temperature service, Spiral wound Gaskets are preferred

compared to solid metal.

3. Where Spiral wound Gaskets are used, a means to prevent over compression shall be

provided.

4. Solid metal Gaskets including welds shall l be at least 20 BHN softer than the Gasket

contact surface

Addition to R 6.5 Gasket joint details



Page | 30

1. Gasket contact surfaces (other than nozzle flange facings) shall have a finish equivalent to 125

micro-inch root mean square (RMS) or 139 arithmetic average (AA) roughness height, but not finer

than 80 RMS or 89 AA roughness height.

2. The flatness tolerance (maximum deviation from a plane) on peripheral gasket contact surfaces

shall be +/- 1/32” (0.8 mm). Use of a straight edge to determine flatness tolerance is acceptable.

3. For special applications such as high pressure, high temperature or Hydrogen service, the

following requirements shall be met when specified

i) The flatness tolerance on peripheral Gasket contact surfaces shall be

Exchanger nominal diameter +/- Tolerance

15” and less 0.003” 0.08

Over 15” to 30” 0.006” 0.15

Over 30” to 45” 0.009” 0.23

Over 45” 0.012” 0.30

Note:

Measurement shall be made by a Dial Indicator

ii) For Exchanger without internal pass partition covers, the flatness tolerance on individual pass

partition grooves shall be +/- 1/32” (0.8 mm).

4. Measurement of the girth flange flatness tolerance shall be made after attachment to the

component cylinder or to the cover after post weld heat treatment.

5. The flatness of TubeSheet Gasket connect surface shall be measured after expanding or welding

the Tube to TubeSheet joints.

5.7 TubeSheets

Addition to R 7.12 Effective tubesheet thickness

Where Tubes are to be strength welded to tubesheets allowance must be made for truing up gasket

face after welding.

Exception to R 7.121 Applied TubeSheet facings

Applied TubeSheet facing shall not be used.

Exception to R 17.16 Packed Floating TubeSheet type exchanger

Packed Floating Head and packed Floating TubeSheet design are not acceptable.

Addition to R 7.3 Special cases

The Stationary TubeSheet on the vertical unit with the Channel down shall be provided with a

suitable means of holding the Bundle in place when the Channel is removed. When Collar Bolts or

drilled & tapped holes are used, at least four shall be provided and their location shall be identified.

New item to R 7.4 Tube holes in TubeSheets

The nominal distance between the edge of the Tubeholes and the edge of all Gasket grooves shall

be not less than 1/16” (1.5 mm) for tubesheet with expanded Tube to TubeSheet joints and not less

than 1/8” (3 mm) for strength welded TubeSheet joints. The tolerance shall be 0.2” (0.5 mm).

Addition R 7.41 Tube hole diameters and tolerances

Where aluminized tubes are specified the nominal diameter shall be increased as necessary to suit

the final OD of the Tube after aluminizing.

Addition to R 7.44 Tube hole grooving

Tube-hole grooves shall be square edged, connecting and free from burrs.

Exception to R 7.61 Seal welded joints

Seal welded joints shall not be used.

Addition to R 7.62 Strength welded joints

1. Tube shall be strength welded to tube sheet when any of the following design conditions exist

i) The pressure differential exceeds 500 psi (3450 kPa).



Page | 31

ii) Any temperature differential exceeds 500oF (280

oC).

iii) The temperature of either the tube side or shell side exceeds the following:

Austenite Stainless Steel: 700oF (370

oC)

Carbon Steel: 850oF (450

oC)

Chromium Molybdenum Steels: 950oF (510

oC)

iv) Steam above 550 psig (3800 kPag) is used.

v) There is a hazard resulting from leakage such as may occur when a Hydrogen stream leaks to a

non-Hydrogen stream.

vi) Leakage at rolled joints would very seriously affect satisfactory operation.

vii) The temperature is within the creep range of the material.

viii) Clad or weld deposited TubeSheets are used in Water service.

Substitution to R 7.63 Fabrication and testing procedure

1. The fabrication and testing procedure for strength welded joints shall comply with section 2 of

Technical specifications. However the annulus between the Tube and TubeSheet shall be closed by

light rolling after welding and gas leak testing, but before pressure testing. Pull test shall be

performed and a minimum strength shall be not less than specified for the tube material, as

determined from the force to cause failure for a given thickness of tube.

2. The joint design, welding procedure (including heat treatment where required) and method of

inspection and testing shall be submitted for HPCL approval.

3. On completion of welding, TubeSheet Gasket faces shall be checked for trueness and shall be

skimmed where necessary.

Additions to R 7.8 TubeSheet pulling eyes

1. Plugs in unclad TubeSheet shall be of the same material as the TubeSheet.

2. For clad TubeSheet the provision for pulling is subject to HPCL’s approval.

3. Where specified in the PO, additional provision shall be made for Tube Bundle removal by means

of an Extractor.

4. Tapped holes shall be designed for a pulling force equal to at least 150% of Bundle weight.

5.8 ChannelCovers and Bonnets

New item for R 8.1 Channels and Bonnets

1. Channels with removable covers shall normally be supplied. Purchaser’s approval is required for

designs incorporating Bonnet (Integral Covers) front end heads.

2. Stay Bolts shall not be used.

Addition to R 8.14 Post weld heat treatment

Fabricated carbon steel channels and bonnets shall be post weld heat treated where the tube side is

in amine or caustic service (regardless of operating temperature)

5.9 Nozzles (R 9)

Additions to R 9.1 Nozzles construction

1. Nozzle attachment to shell or channel shall be by full penetration welds unless in

cooling water or other non-hazardous service with design pressure not exceeding 150 psig where

partial l penetration welds are acceptable.

2. All nozzles 2” and larger nominal size shall be flanged.

3. Each section of a reinforcing pad shall contain a test hole tapped 1/8” NPT prior to

installation. After air testing, the holes shall be left unplugged and filled with grease.

4. Flanges shall be integral type per ASME VIIII, Div. 1 except that slip on flanges are

permitted on unclad or unlined carbon steel exchangers where the design temperature is below

450oF (230

oC), the flange rating is CI 150 and where there are no cyclic conditions of pressure and

temperature.

5. Nozzle flanges shall be to ANSI B 16.5.



Page | 32

6. CI 900 ANSI raised face flanged shall have a gasket face finish of 125 micro-inch

approximate roughness. Lower rated flanges shall have a gasket for finish as per ANSI B 16.5.

7. In computing reinforcement requirements, no credit shall be taken for any excess

material in the nozzle, shell or channel.

8. No adjustment to the nozzle setting is required to compensate for the slope specified

in para 4.7 (b) of this specification.

Addition to R-9.2Nozzle installation

Cutting of openings through welded joints shall be avoided.

Addition to R-9.3 Pipe Tap connections

1. Pipe tap connections shall not be used on Austenitic Stainless Steel clad Exchangers

parts.

2. Blind flanges shall be provided for flanged vent and drain connections together with

bolts or studbolts and gaskets.

3. Openings ¾” to 1½” inclusive in casting shall be tapped integral bosses.

Addition to R-9.31 Vent and Drain Connections

Drains shall be provided on the Channel end and Vents at the Floating Head end.

Amendment and addition to R-9.4 Stacked Units

1. Intermediate nozzles between units shall have raised face Flanges unless otherwise

specified.

2. Vendor shall supply Gaskets and Bolts for interconnecting nozzle Flanges.

3. When Shells of stacked units are flanged together or are connected with a spool piece,

the connection shall be fitted with spectacle blind designed to match the Flange ratings.

4. Bolting shall be removable without moving the Exchangers. All nozzle projections shall

exceed the Stud length plus insulation thickness where insulation is specified.

5.10 End Flanges and Bolting (R-10)

Addition to R-10 End Flanges and Bolting

1. The nominal clearance between flanges after assembly shall not be less than 1/8”

(3mm). The clearance between flanges shall extend within the bolt circle to permit checking flanges

for radial distortion caused by an excessive bolt load.

2. When nubbins are provided on the flange face, they shall be located in the female

(grooved) flange.

3. Flanges shall not be directly cut from flat plate but may be machined from plate, which

has been formed into a ring.

6.0 TEMA SECTION 8 - MATERIAL SPECIFICATIONS

6.1 General (M-1)

New Items for M-1 General

1. Materials may be specified by HPCL without knowledge of many of the design details to

be offered by the Vendor. Vendor shall assume responsibility for correct incorporation of materials

in the design and should therefore recommend alternatives, if required, giving the reason for the

suggested change. All changes are subject to HPCL’s approval.

2. Material for each component of an exchanger shall be specified on the Data Sheet.

When only the type of material is given, the appropriate material specification shall be selected

from the code. VENDOR may offer substitute materials but these are subject to HPCL’s

approval.Where the material selected is not included in ASME VIII Div I, then the mechanical

properties of an equivalent ASME Div. I material, which shall be agreed by HPCL, shall be used in

design. Due allowance must be made for any changes in dimensional tolerances.

3. All Chromium Molybdenum Steels containing up to 9% Chromium which are to be

welded shall have a Carbon content not exceeding 0.15%.



Page | 33

4. Unless otherwise specified in the PO, Data Sheet or attached drawings, all materials

used for supports, clips etc. which are to be welded directly to the vessel shall be of the same

material as the vessel at the point of attachment.

5. No bottom or side air or enriched air blown converter steels (e.g. Bessemer or Thomas)

shall be used.

6. Oxygen blown Converter Steel may be used below the creep range only.

7. HPCL’s approval is required for carbon and carbon manganese steels where the carbon

or carbon equivalent (C + Mn/6) content is in excess of 0.25% and 0.41% respectively.

8. Vendor shall specify material for test rings. Cast materials shall not be used.

6.2 Tubes (M-2)

New Items for M-2 Tubes

1. All tubing material shall be in the full-length annealed temper except arsenical copper, which

shall be half-hard temper. Non-ferrous tubes shall have the following maximum hardness

values: CuNi - 140 VPN

Admiralty - 110 VPN

Al. Brass - 110 VPN

Copper - 80 VPM

2. Steel tubes that are welded to tubesheets shall be made from fully silicon killed steel.

3. Tubes to OCMA Specification HET 1 are acceptable.

4. Where aluminized tubes are specified VENDOR shall make due allowance for shrinkage in

length and increase in outside diameter. VENDOR shall ensure that the requirements for

tube end masking are met. In the case of the rolled tubes, the external aluminizing shall be

stopped just short of the inner-most tubesheet groove. For tubes requiring strength

welding to the tubesheet the interior and exterior aluminizing shall be terminated 1/2”

(12mm) from the weld.

Addition to M-2.21 Carbon Steel

1. Carbon steel tubes manufactured by electric resistance welding shall comply with the following

requirements:

i) the flash shall be removed.

ii) the welds in the tubes shall be inspected 100% by eddy current or ultrasonic using the VENDOR

usual inspection procedure,

iii) the tube shall be full section normalized after welding and also tested hydrostatically for at least

20 seconds.

iv) when rimming steel is used, strips shall be rolled in single widths, i.e., they shall not be slit

longitudinally.

Exception to M-2.22 High Alloy Steel

The use of welded tubes is not permitted.

Exception to M-2.223 Cr-Ni-Mo-Cu-Cb (Alloy 20Cb-3) :


Exception to M-2.24 Copper and copper Alloy :


6.3 Shells, channels, covers, floating heads, tubesheets and flanges (M3)

Fully silicon killed steel of good welding quality shall be used for tubesheets when strength welded

tube joints are required. For good weld-ability, the tubesheet shall preferably have the following

composition.

Element Percent

Carbon 0.15 max.

Manganese 1.0 - 1.4

Sulphur0.035 max.



Page | 34

Phosphorus 0.035 max.

2. Where austenitic stainless steel deposit lined steel is specified on the datasheet for outer

pressure containing parts, the substitution of solid Austenitic stainless steel plate is not permitted

unless the maximum design temperature is 140oF (60

oC) or less.

6.4 Baffles, Supports, Tie Rods and Spacers (h-4)

New items for M-4 Baffles, Supports, Tie Rods and Spacers

1. Bundle impingement baffles shall be 12 Cr steel except for austenitic stainless steel bundles

where they shall be of the same type of austenitic stainless steel.

2. Baffles, supports, tie rods and spacers shall be made of material having an anticipated life at least

equal to the tubes. In the case of titanium tube bundles, baffle material shall be agreed with HPCL.

3. Tie rods and spacers shall be made of materials having a similar coefficient of expansion to that

of the tubes.

6.5 Bolting (M-6)

Amendment to M-6.1 Studs and Stud Bolts

Material shall be in accordance with the Data sheet /PO.

Amendments to M-6.2 Nuts

Material shall be in accordance with the Data sheet/PO.

7.0 GENERAL REQUIREMENTS (items not related to TEMA)

7.1 Design

a) On single pass Tubeside units where internal expansion joints are used, these shall be

designed for the full internal and external pressure to be applied independently unless

otherwise agreed with HPCL. The number of cycles which the joint will withstand under

the design conditions shall be advised.

b) Shell Covers and Flat head Covers for pull through type Exchangers and liquid Channel

Covers shall be provided with Jack Screws for ease of dismantling.

c) Vents shall be provided in all pads and similar attachments.

7.2 Material Status and Sub-Orders

a) The Manufacturers shall make available for the HPCL’s representative full information on

thestatus of sub-orders for material and on the progress of shop work.

b) Promptly upon receipt of the PO, Vendor shall proceed with all necessary sub-orders or

otherwise procure material required for manufacture. The release of sub-orders for

material shall be delayed pending approval of the Vendor’s drawings, unless otherwise

specified.

Attachment I Exchanger Standard Attachment

ANNEXURE –IIto PR

STANDARD SPECIFICATION FOR EXPANDED TUBE TO TUBESHEET JOINTS

1.0 SCOPE

This specification covers the expanded Tubeto Tube Sheet joints for Heat Exchangers. For the purpose

of this specification, the terms “Joints” shall be construed to mean “Tube-to-Tube Sheet joints”. The

fabrication procedures contained in this specification are for the purpose of outlining procedures,

which when used with proper workmanship, will produce leak-free joints. However, it is Fabricator’s

responsibility to furnish sound, leak-free joints.

2.0 TYPES OF JOINTS

Joints with two grooves shall be standard unless specified otherwise.

3.0 MATERIAL FOR MOCK UP

Materials for mock up shall be as specified in the drawing. Generally, same materials shall be used for

procedure testing. Alternate materials are acceptable only if written approval of HPCL has been

obtained. Tube Sheet thickness for procedure testing shall be equal to the maximum thickness of the

Tube Sheet except that it need not exceed 55mm.

4.0 CARE OF TUBES

Ends of the Tubes (Tube Sheet thickness + 100mm) shall be subjected to careful visual inspection.

These shall have no scaling, scoring, or rough surface. Repairs, if required, shall be carried out only after

permission from HPCL/Third Party Inspector has been sought. Repairs, if carried out, shall be such that

Tube dimensions are within the tolerances specified for the Tube material. Otherwise, the Tube shall be

discarded.

5.0 TUBE HOLES IN TUBESHEETS

Tube holes in Tube Sheets shall be drilled as per TEMA-Special close fit. Wherever standard fit is

desired, same shall be indicated specifically on the drawings.For metric Tube of size 20mm OD, the

nominal size of holes shall be 20.20 mm, with tolerances as +0.05mm. For 25mm OD Tubes, nominal

size of holes shall be 25.25mm, with tolerances as +0.05mm. Holes in Tube Sheets shall be drilled and

reamed to final size. Holes shall have no burrs or scoring marks and shall be circular with parallel sides

and normal to the Tube Sheet surface. Edges of the holes shall be de-burred.

6.0 ASSEMBLY OF TUBES

Clean the holes and ends of Tubes of any rag, dirt or any other solid matter, oil, or grease etc. Care shall

be taken during assembly to avoid scoring of Tube holes in Tube Sheet or outer surface of the Tubes.

Tubes shall be so positioned that their projection from the Tube Sheet is as per drawing.

7.0 TUBE EXPANDERS & EXPANDING OF TUBES

7.1 Tube Expanders used by the Fabricators shall be electronically controlled type and shall be in

good condition and shall have Inspector’s approval. Tube Expanders shall have stops toprevent

the Rollers approaching nearer than 3mm to the back of the Tube plate.

7.2 Tubes shall be expanded into the Tube Sheet by using the equipment and settings as previously

agreed between the Inspector and the Fabricator. Such settings may be required to be proved by

procedural testing, or at the discretion of the Inspector, Fabricator’s established settings may be

used.

7.3 Tubes shall be expanded for the full thickness of the Tube plates less the 3mm at the back-sideof

the face of the Tube Sheet. However, for Tube Sheet thickness more than 5 times Tube OD,

expansion may be limited to 4 x Tube OD on the front side and 1 x Tube OD on the back side of

the Tube Sheet. Care shall be taken to avoid any distortion of the Tube Sheet or gross

deformation of the ligaments. It is suggested that Tubes be expanded systematically in small,

diametrically opposite groups.


8.0 PRESSURE TESTING

8.1 After expansion of all Tube joints in Exchanger is completed, Tube Sheet face and the internal

surfaces of the Tubes to a length of about 15mm shall be thoroughly cleaned. Any Grease or Oil

shall be suitably removed by the use of proper Solvent or by Steam jets. These joints shall then

be subjected to Pneumatic Air-Soap Solution Test of 1.25kg/cm2g. Leaking Tubes shall be further

expanded in the presence of HPCL‘s authorized Inspector after reasons for the leakage have been

ascertained and accepted by the Inspector. If excessive thinning (>15%) has taken place it has to

be reported to HPCL’s/Third Party Inspector before such expansion is carried out.

8.2 Expanded joints shall also be subjected to hydrostatic leakage test at a test pressure indicated in

the drawing. Leakage, if any, shall be reported to HPCL/TPI. However, leaking Tubes, if any, may

be further expanded keeping the guidelines given above in view. Water for hydrostatic testing,

shall have approximately 2% (by volume) of an approved wetting agent in addition to 0.2% of

Sodium nitrite as Corrosion Inhibitor. Draining and drying requirements shall be as per HPCL’s

specification.

9.0 PROCEDURE TESTING

9.1 Procedure testing is required to be carried out when –

a) The Inspector requires it, or

b) For those combinations of Tube to Tube Sheet materials and sizes of Tubes for which torque

value for optimum expansion have not been established by Vendor to the satisfaction of

inspection authority, or

c) It is a requirement of the Code/Purchase Order/Equipment drawing or

d) Load carrying capacity of the Tube-to-Tube Sheet joint is required to be certified.

9.2 In all the above cases, complete procedure testing to demonstrate the following shall be carried

out:

a) % thinning vs. machine setting

b) Shear load test

10.0 PERCENTAGE THINNING REQUIREMENTS

Percentage thinning shall be defined as follows:

% thinning = 1 - (Dh - IDf)

---------------x100

ODi-IDi

Where

Dh = Hole diameter in Tube Sheet

IDf= ID of Tube after complete expansion

ODi= OD of Tube before expansion

IDi= ID of Tube before expansion

10.1 A sample Tube Sheet of same material and thickness as required for regular production shall be

drilled, reamed and grooved as per drawing. Holediameter shall be as specified. Tube Sheet

thickness used for procedural testing shall be as per drawing except that it need not exceed 55

mm for Tube Sheet having thickness higher than 55mm. Diameter drilled in the sample Tube

Sheet shall be measured accurately. A sample Tube shall be selected which represents average

dimensions for the lot and its OD and ID shall be measured. Tube shall be positioned in the hole

and assembly held in the same position as shall be adopted for production. Tube Expander to be

used for production shall be set at an estimated low value and Tube shall be expanded inside the

Tube Sheet hole. Expander setting shall be increased until the thinning is in the range of 8-10%

for all materials except Stainless Steel in which case it shall be 6-8%.

10.2 Expander setting thus found shall be tested on the following combinations and thinning shall be

checked to be within the range specified above:

Combination required for checking the Expander setting


Hole dia with tolerance Tube with tolerance

OD Thk

+ + +

+ + -

+ - +

+ - -

- + +

- + -

- - +

- - -

10.3 Combinations selected will use Tubes with extreme tolerances as far as obtained from the given

lot of Tubes. Great accuracy shall be used in drilling holes in sample Tube Sheet with extreme

tolerances. Results of these tests (reporting combination number and % thinning achieved and

various diameters used for calculation of thinning) shall be reported to HPCL/TPI.

10.4 Vendor is advised to satisfy himself that settings reported and to be used in the production shall

be the best for the job and would enable him to give workmanship guarantee for the equipment.

HPCL’s approval shall in no way relieve the Vendor of his responsibility and guarantee to supply

the Equipment as per the conditions of the Purchase Order.

10.5 Samples prepared above, shall be cut in two halves along the axis of the Tubes to show the flow

of metal into the grooves. These cut-sections shall be presented to the Inspector who shall check

the samples for flow of metal into the grooves and also check the expansions length. Inspector’s

approval shall be sought before Expander setting is approved.

11.0 SHEAR LOAD TESTS

Shear Load Tests shall be carried out as per Appendix-A of ASME Boiler and Pressure Vessels Code,

Section VIII Division 1. Factor of reliability of the joint shall be established and shall be demonstrated to

be greater than or equal to Fr (test) as per Appendix-A table. Actual value shall be reported in the Test

Reports.

12.0 INSPECTION STAGES AND INSPECTION

12.1 Inspection of the Equipment shall be carried out by HPCL’s Inspector/TPIas per the PO. For

expanded Tube joints, following stages of inspection shall be observed and reported:

a) Inspection of Tubes and Tube Sheet materials

b) Special attention shall be paid to Tube dimension. These shall be within the specified

tolerances.

c) Agreement regarding expansion procedure

12.2 If previously established procedure of the Vendor is to be used, Inspector has the option of

asking for demonstration of the procedure to satisfy himself of its accuracy or to confirm the

suitability of the expanding equipment or control unit. With time, the equipment used for

expansion may change its characteristics and Inspector may like to check this by actual

procedure tests.

12.3 If procedure testing is to be carried out, all tests preparations, etc. shall be inspected by the

Inspector.

12.4 When holes in the Tube Sheet have been drilled, reamed and grooved, all holes shall be given a

careful check for:

a) Tube layout pattern

b) Holes being perpendicular to Tube Sheet surface, circular with parallel sides free from any

scoring marks, grooves being properly located and of required dimension and surface of holes

to be at least 1.6 microns (average) or better.

c) Minimum ligament width as per drawing or code.

d) Check the Tubes and their ends before assembly is complete and before expansion is to be

started.


e) Agree to the sequence of expanding Tubes into the Tube Sheet holes.

f) Check for distortion of Tube Sheet and thinning of Tubes after expansion is complete.

g) Witnessing of pneumatic & hydrostatic testing.