ES.5.14.0010 - Rev a - Fab'n, Insp'n & Install'n of CS Pipework

8/11/2019 ES.5.14.0010 - Rev a - Fab'n, Insp'n & Install'n of CS Pipework

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CONTENTS

Foreword

1.0 Introduction

2.0 Custodian

3.0 Purpose

4.0 Application

5.0 Responsibilities of the Contractor

5.1 Workmanship5.2 Personnel5.3 Materials5.4 Substitutions and Modifications5.5 Errors and Omissions

6.0 Quality Assurance

6.1 Documentation

7.0 Materials

7.1 Piping Materials7.2 Material Control at Site7.3 Transportation, Storage and Handling

8.0 Fabrication, Assembly and Erection

327 General328 Welding330 Preheating331 Heat Treatment332 Bending and Forming335 Assembly and Erection

9.0 Inspection, Examination and Testing

340 Inspection341 Examination342 Examination Personnel343 Examination Procedures344 Types of Examination345 Testing

Tables

Table 1 Welding Procedure Qualification Test Requirements


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Table 2 Welding Procedure Thickness/Diameter Qualification Ranges

Table 3 Recommended Filler Metals for P-Numbers 1 thru 5

Table 4 Minimum Recommended Preheat Levels

Table 5 Post Weld Heat Treatment

Table 6 NDT Acceptance Criteria

Table 7 Extent of Non Destructive Testing

Figures

Figure 1 Removal of Charpy V-Notch Specimens

Figure 2 Location of Hardness Indentations

Figure 3 Dimensional Tolerances

Figure 4 Post Weld Heat Treatment Requirements for Set-On and Set-In Nozzles

Figure 5 Local Heat Treatment for Branch Connections

10.0 Approval to Deviate

11.0 Revision History Log

12.0 Glossary

13.0 Bibliography


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Foreword

This document is a reformatted version of the QGPC Specification ES.L.22 Specification for theFabrication Inspection and Installation of Carbon, Carbon-Manganese and Low Alloy FerriticProcess Pipework issued in November 1996.

In this issue the specification was renumbered and reformatted as per the engineering standardsES.0.07.0013 and ES.0.06.0020 respectively. Also the reference piping code ASME/ANSI B31.3 waschanged from 1993 version to the 1996 version.


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1.0 I ntroduction

This specification details QGPCs supplementary requirements to ANSI/ASME B31.3 -1996 Edition, Process Piping. It is specific to Chapters V and VI and is applicable for allQGPC Production Facilities, both Onshore and Offshore.

Unless specifically excluded in the contract the scope shall include all process, utility piping and in-line instrumentation piping. The welding of riser pipework andtransmission pipelines is outside the scope of this specification.

Erection shall consist of complete installation of piping systems as defined by the pipingdrawing documents. It includes the installation of all piping, piping components andrelated examinations, inspection testing in both shop and field environments.

2.0 Custodian

The Custodian of this specification is EE, who is responsible for the accuracy and qualityof its contents and for its future revisions, where these are required to reflect industrytrends or changes to QGPC business practices.

3.0 Purpose

The purpose of this specification is to define QGPCs supplementary requirements toANSI/ASME B31.3 (Process Piping) for fabrication, inspection, testing and installation.

4.0 Application

This specification shall be used by project teams, business units and Contractors or Consultants employed by them. This specification shall be enforced in new projects or when refurbishing the existing piping.

5.0 Responsibilities of the Contractor

5.1 Workmanship

The Contractor shall ensure that all materials, workmanship and inspection conform tothe requirements of this specification and shall supply all labor, tools, consumables,equipment and services necessary to accomplish this task.

5.2 Personnel

The Contractor shall have fully experienced supervisory personnel in charge of all aspectsof the work, and shall employ only fully qualified craftsmen to carry out the work.Qualification requirements shall be as per ANSI B31.3, ASME IX and additionalrequirements as specified in the contract documents and all curriculum vitaes shall besubmitted to the Employer for prior approval.

5.3 Materials

The checking, preparation, fabrication, inspection and non destructive testing of allmaterials to be used shall be the responsibility of the Contractor, and shall be in


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accordance with the requirements of this specification. All such work shall be to theContractors account.

5.4 Substitutions and Modifications

The Contractor shall make no substitution of materials and/or modification of details,without the prior approval of the employer (and Third Party Inspectorate, whereapplicable). The Contractor shall submit, in writing, all such changes to the Employer for approval.

5.5 Errors and Omissions

The Contractor shall be responsible for all errors and omissions in the detailing, layoutand fabrication. It is and obligation of the Contractor to check the Employers documentsand drawings and to notify the Employer of any errors or omissions.

6.0 Quality Assurance

The Contractor shall have a current and implemented QA system and QC procedures for shop and field piping fabrication, erection, etc., in compliance with the requirements of ISO 9000 for all works undertaken and meet the Employers specified requirements.

The Contractor shall, within two weeks of receipt of the order, submit for approval adetailed quality program for welding and fabrication which complies with the applicableclauses and elements of ISO 9000 standards.

It shall define the structure, welding and fabrication responsibilities, authority levels andinternal and/or external interface arrangements of personnel.

It shall identify the items and services to which this specification applies the level of

control and verification.

It shall provide documents such as plans, procedures and instructions for theaccomplishment of welding and fabricating activities to provide the required quality,taking into account the need for special controls, tests, tools, skills, etc.,

The Contractor shall be responsible for ensuring that the final documentation and records provide the necessary objective evidence that the quality required has been achieved.This shall include the results of inspections, tests, monitoring of work performance,material and weld identification and related data such as qualifications of personnel and

procedures.

The Contractor shall provide all necessary certification and documents in accordance withthis Specifications identified by the Employer.

The Contractor shall appoint only qualified and experienced personnel with the necessarylevel of authority to ensure compliance with the requirements of this specification.

6.1 Documentation

6.1.1 General

The documents to be prepared by the Contractor to facilitate the fabrication andinstallation of the piping shall provide full and complete information and instructions


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including detailed methods and procedures. Approval or review of drawings by theEMPLOYER or his representative shall not relieve the Contractor of his responsibility tocomplete the work in accordance with the Contract Specification.

6.1.2 Document Submission

The Contractor shall, as a minimum, submit the following documentation to theEmployer for approval at least two weeks prior to the commencement of work:1) Fabrication, welding and installation procedures.

2) Fabrication drawings including identification of material grades, welddetails and NDT requirements.

3) List of proposed welding consumables.

4) A Register of proposed welding procedures and their areas of application.

5) PQRs and qualified WPSs including those for weld repair, in accordancewith this specification for both permanent work and temporary attachments.

6)

Certification of welders and welding operators qualified in accordance withthis specification. Documents detailing qualifications and experience of engineers and all QA and QC personnel.

7) Procedures for the receipt, storage, handling and issue of weldingconsumables.

8) Material identification (including welding consumables) and control procedures.

9) Certificates for all Contractor supplied material (including weldingconsumables).

10) Procedures for Inspection, NDT, Examination and Testing, Format of thereports and personnel qualification.

11) Post Weld Heat Treatment procedures and instructions sheets.

12) Forming/Bending Procedures.

13) Hydrostatic Test Procedure.

7.0 Materials

7.1 Piping Materials

Unless stated otherwise in the contract Specifications, drawings, documents and all piping materials required to execute the works shall be supplied by the Employer inaccordance with the relevant Specifications listed in Section 13.0 of this specification.

Alternative materials may only be substituted with the Employers prior writtenagreement.

Pipe lengths and pipefittings, unless otherwise specified, shall be supplied to themanufacturing tolerances of the applicable standards.


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7.2 Material Control at Site

A quarantine store shall be established at the fabrication site to hold material awaiting proof of compliance with specified requirements.

A secure store, for holding those materials which after completion of site inspection are proved to be satisfactory and to be complete with all necessary and identifiablecertification, shall be similarly established.

The Contractor shall establish both the quarantine and the secure stores and shall submitdetails of design, layout and organization to the Employer for approval. Special

precautions shall be taken to ensure that all material used for fabrication and installationof piping is fully documented and available prior to release to fabrication and installation.

The Contractor shall adopt the color coding system specified in ES-M-11 to identifydifferent types of materials.

The Contractor shall establish procedures for the transfer of identification marks when pieces are cut from their parent pipe as required by the quality plan. Pipe identification

shall be completed prior to cutting.

7.3 Transportation, Storage and Handling

The Contractor shall ensure that adequate protection against damage is provided for allcomponents during any storage, loading and transportation activities, by providingadequate timber bearers during the transport and the wrapping of lifting points.

Pipes and completed spools or component parts shall be stored above the ground on pallets, timber blocking or other similar supports, so as to be kept above the level of anystanding water and be kept free from dirt, grease, paint sprays and any other harmfultreatments which in the opinion of the Employer could affect its ability to perform its

intended function.

Contractor shall protect all open ends of pipes and flanges by the use of plastic end capsand timber blinding respectively

The Contractor shall provide adequate and safe lifting slings or similar equipment duringhandling or lifting operations. The use of chains for lifting is forbidden. When pipes arelifted by their ends soft faced hooks shall be used.

Damage to any part of the pipework or sub-assemblies either before, during or after installation shall immediately be brought to the notice of the Employer.

All completed spools shall be transported by a method, which does not induce significantdeformations or stresses. Care shall be taken in the suitable placement of lifting lugsand/or temporary attachments.

Particular care shall be taken in the storage and handling of parts which have been metalsprayed, galvanized, painted, etc., and should the coating be damaged it shall be restoredto comply with the appropriate coating by a method approved by the Employer.

Different grades of material, including cut segments or shapes shall be clearly markedusing an identification coding system approved by the Employer. The steel types shall bestored in well defined locations to avoid inadvertent mixing.


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The cutting of pipes and/or plates and transferring of marks and where pertinent, the particular identity of the piece shall be carried out in such a manner that a particular gradeof material can at any time be identified within a spool, installation etc. If any material isfound without the appropriate reference the Contractor shall prove the identity of thematerial to the satisfaction of the Employer.

8.0 Fabrication, Assembly and Erection

This section is supplementary to Chapter V of ANSI/ASME B31.3 - 1996 Edition. Itcovers the requirements and procedures for the welding of process pipework in theworkshop, yard and offshore. For convenience the headings and numbering system usedwithin this section follow those of ANSI/ASME B31.3.

The clauses of this section do not relieve the Contractor of his responsibilities, guaranteeor of any other contract bond with respect to welding performance and welding results.During welding operations, inspection and testing, the Contractor shall observe andfollow current regulations concerning personnel safety, prevention of fire, explosions andaccidents.

No exception to this section is allowed without the written authorization of the Employer.

327 General

327.1 Processes

All welding including tack welding etc., shall be accomplished with a low hydrogen processes, which shall deposit weld metal with a diffusible hydrogen content less than10ml per 100g of deposited weld metal. Tests to confirm the diffusible hydrogen levelshall be conducted to BS 6693, if requested by the Employer. These tests shall be at theContractors expense.

Acceptable welding processes for the fabrication of pipework are SMAW, GTAW andSAW.

(Addition)

Other welding processes shall not be used without the approval of the Employer. If alternative processes are intended to be used, any such proposal shall, at the bid stage,state all items and areas of intended use, together with full details of the process,consumables and Contractors past history of use. The Employer may refuse, or limit theuse of an intended process, and may specify additional testing and inspectionrequirements.

328 Welding

328.2 Welding Qualifications

328.2.1 Qualification Requirements

(a) The Contractor shall conduct the tests required to qualify the procedures and theseshall be witnessed by the Employer (and the CA if specified in the contractdocuments).

WPSs shall be submitted and approved specifically for the Employer prior tocarrying out procedure qualification. Existing pre-qualified procedures may be


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considered, subject to the submission to the employer of full documentation. If pre-qualified procedures are accepted, the Employer reserves the option to re-qualify arepresentative number of them

Prior to qualifying the welding procedures the Contractor shall submit for approvala schedule of Welding and Repair Procedure Specifications and drawings todefine the scope and the intended areas of application.

Welding procedure specifications shall, as a minimum, record the informationrequired below:

1) The steel type, grade, P-Number, carbon equivalent and thickness used for qualification.

2) The welding process (or processes when a combination is used)

3) The type, size, classification, F-number and A-number of the weldingconsumables

4) For each run, the proposed arc current and voltage; width of weaveelectrode run out length and burn off time for SMAW; welding speed and

calculated heat input5) The weld preparation including tolerances

6) The cleaning method proposed

7) Applicable welding positions and directions

8) The minimum preheat and maximum interpass temperatures

9) The treatment to the second side, e.g. purge gas and purge rates

10) A sketch showing, as a minimum, the deposition sequence of the first four layers. If the weld is double sided, show the second side root depositionsequence

11) Any deposition augmentation system used12) Consumable treatment where this forms part of the procedure, e.g. baking

temperature and time

13) Tack welding procedure (tack size and separation)

14) Wire stickout, if applicable

15) For SAW, the angle of inclination of the electrode to the workpiece andstand-off

16) PWHT, where applicable

All welding procedure qualification testing shall be performed on materialapproved by the Employer. The use of other material may be accepted at the solediscretion of the Employer provided it complies with the project materialspecification. The heat number and certification number shall be recorded.

Weld test pieces shall be of sufficient size to allow all the tests and permitted retestspecimens. Retesting shall only be permitted on test specimens removed from theoriginal test weld.

Should the test weld fail any of the required tests and the permitted retests, thecause of the failure shall be established to the satisfaction of the Employer andrectified. The complete procedure test shall then be repeated.


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A qualified welding procedure is one, which has been tested to, and has achievedthe requirements of this specification and has been approved by the Employer.

Qualification of a welding procedure is restricted to the Contractor who conductedthe welding procedure test.

Production welding shall not commence until the appropriate procedure tests andWPSs have been approved by the Employer.

The use of plate qualifications to support a welding procedure for pipework is not permitted.

(Amendment)

(d) Impact testing shall be conducted for all materials where these are required for the base material or where the minimum design temperature is below -10 oC.

Impact testing shall be performed on specimens removed as detailed in Figure 1 inaccordance with ASTM A370. The number of specimens shall be as indicated inTable 1, however where the thickness of the weld exceeds 25mm and additional set

of three specimens shall be taken, with the notch at the root of the weld. Specimensshall be etched in order to accurately locate the Charpy V-notch.

Impact tests shall be carried out at the minimum design temperature or the parentmetal test temperature, whichever is the more stringent.

The acceptance criteria shall be as per Table 323.3.5 of ANSI/ASME B31.3.

If the minimum average impact value is not attained and only one specimen showsa value less than the minimum individual value, three additional specimens shall beselected from a position similar to that from which the set of specimens under consideration were taken. The value of each of these retest specimens shall equal or

exceed the required average value and the average of all six specimens shall exceedthe required average.

Subsize specimens are only acceptable where full size specimens cannot beextracted from the test welds. The largest possible subsize specimen shall be taken.Adjusted temperature and acceptable criteria shall be based upon the maximumthickness qualified by the PQR rather than the actual test coupon thickness.

(Amendment)

(e) The use of consumable inserts is not permitted. (Amendment)

(f) P-Numbers

The extension of welding procedure specification from the material on the PQR toa material of different specification, even if it has the same P-Number, shall only

be permitted with prior approval of the Employer. (Addition)

(g) Changes which require a new welding procedure specification qualification, are:

(i) A change of thickness or diameter outside the ranges specified in Table2.(ii) An increase in the minimum specified preheat temperature of more than

50C.


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(iii) Any decrease in the minimum specified preheat temperature.(iv) A change in the type of current, i.e. AC to DC, or a change in electrode

polarity.

(v) For non-impact tested procedures a change of consumable classificationrequires the qualification of a new welding procedure.

(vi) For impact tested procedures a change of consumable classification or brandname requires the qualification of a new welding procedure.

(vii) Any change in wire/flux combination.(viii) A change in shielding gas type or nominal composition.(ix) A change of weld preparation in shape or configuration including fit-up

tolerances.

(x) For the root and capping passes any change in the electrode size and for other passes any change of more than one increment size in the electrodesize used in the qualified welding procedure.

(xi) Any change in the post weld heat treatment temperature or time.

(xii)

The introduction of any deposition augmentation system (e.g. iron powder or hot wire additions).

(xiii) Any change in the rate of addition of any supplementary consumable.In addition to the above, the following changes, when made, shall require re-qualification where weld metal and HAZ toughness is a requirement.

(xiv) A change from multipass to single pass or vice-versa.(xv) Any change in the electrode diameter or weave width beyond that used in the

qualification test or a change in any other parameter likely to increase heatinput or decrease toughness.

(xvi) Any decrease in the minimum specified preheat or an increase of more than20oC in the interpass temperature from that qualified subject to themaximum interpass limitations.

(Addition)

(h) All welding procedure qualification test welds shall be subjected to radiographicand magnetic particle examination and where applicable ultrasonic examination

prior to mechanical testing. (Addition)

(i) A photomacrograph of each hardness macrosection at a magnification of X2 suchthat the hardness indentations are clearly visible together with a sketch identifyingthe indentations shall be submitted with the welding procedure qualification testreport to the Employer for approval.

All welding procedure shall be subject to a macro examination and hardness surveyin accordance with Figure 2 using a Vickers pyramidal indenture with a 10 Kgload. A dendritic type etchant shall be used to ensure clear definition of the fusionline. The maximum hardness allowable is 248 Hv 10 for all QGPC process pipingunless otherwise specified in the design.

(Addition)

(j) Tubular butt joint test pieces shall be prepared to qualify all welding of pipework.


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For impact tested procedures the test pieces shall be welded in the vertical (5G) andhorizontal positions (2G) and will qualify all position and for non impact tested

procedures the test pieces shall be welded in the inclined 45 o (6G) position and willqualify all positions.

(Addition)

(k) Welders and welding operators shall not qualify on production welds but shallcarry out performance tests. The welders shall be qualified for all passes; the use of

partially qualified welder is not permitted.

Existing qualifications may be considered provided that they relate to a similar standard of work and use welding consumables having the same characteristics asthose to be used in production. Fully correlated documentation demonstratingcurrent qualifications endorsed by an acceptable CA, continuous experience withthe qualified process and satisfactory past performance shall be submitted to theEmployer for consideration. Acceptance of this documentation and existingqualifications shall be entirely at the discretion of the Employer.

All welder and welding operator tests shall be witnessed by the Employer or a CA

approved by the Employer before the welder or welding operator is permitted toweld on any pipework. The decision taken by the Employer regarding thequalification of any welder or welding operator shall be final.

(Addition)

(l) All welder performance tests for all positional welding shall be performed usingthe same materials, P-number, consumable and in the 6G position to qualify all

positional welding in production. In the even that differing material groups are to be welded or when special welding procedures are to be adopted to meet unusualconditions, the welder shall be required to satisfactorily pass additional tests asdirected by the Employer.

(Addition)

(m) All welders shall be qualified by visual, magnetic particle and radiographicexamination.

(Addition)

(n) All welding operators shall be qualified in the position to be used in production. (Addition)

(o) The approval of a welder on a pipe of outside diameter O.D. shall includeapproval for diameters in the following ranges: -

Outside Diameter Tested Range Approved

O.D. 33.4 mm (NPS 1) D.O. TO 33.4 mm (NPS 1)33.4 mm < O.D. 73 mm (NPS 2) 0.5 x O.D. TO 2 x O.D.

O.D. 168.3mm (NPS 6) O.D. 168.3mm (NPS 6)

(Addition)

The use of qualification tests made on plate to qualify welders and/or weldingoperators for pipework is not permitted.

(Addition)


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328.2.2 Procedure Qualification by Others

Not Permitted (Amendment)

328.2.3 Performance Qualification by Others

Not Permitted (Amendment)

328.2.4 Procedure Qualification Record

In order to review and approve a welding procedure the Employer shall require thefollowing documentation, as a minimum, to be included in the welding procedurequalification package:

(i) The PQR sheets

(ii) The production WPS

(iii) The WPS used for the qualification test

(iv) The procedure qualification data sheet of the actual welding parameters applied toweld the test joint verified by the Contractor, the Employer and the CA.

(v) The mechanical test results(vi) The inspection and NDT results.(vii) The parent material test certificates indicating the chemical analysis and

mechanical properties

(viii) The consumable batch certificates indicating the information specified in paragraph328.3.1 of this specification

(ix) the PWHT charts (where applicable)

Records of the test results for each procedure qualification shall be established andcertified by the Employer. One of these shall be kept by the Contractor and shall beavailable to those authorized to examine it. Another shall be given to the Employer.

(Amendment)

328.3 Welding Materials

328.3.1 Filler Metals

All manufacturers of welding consumables shall be subject to approval by the Employer Tables 3 detail the classifications of welding consumables acceptable to QGPC for specific materials.

The Contractor shall inform the Employer of the batch definition used by themanufacturer. Consumables shall be batch tested in accordance with AWS and shall besubject to approval by the Employer.

All as welded weld metal test results classified to AWS for consumables shall have thefollowing mechanical properties as a minimum:

(i) Chemical composition of weld metal

(ii) Tensile and Yield strength

(iii) The percentage elongation


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(iv) Charpy impact data (where applicable)

Special consideration shall be given to the chemistry of the deposited weld metal suchthat, as a minimum, it matches to corrosion resistance of the parent material.

Welding consumables containing more than 1% Ni shall not be used for welding of anycarbon and carbon-manganese ferritic steel pipework. The use of C-1/2Mo consumablesis not permitted.

(Amendment)

328.3.2 Weld Backing Material

Not Permitted. (Amendment)

328.3.4 Shielding Gases

Different types of gas or gas mixtures may be used provided that the quality and type isappropriate to the welding process employed and in agreement with an approved welding

procedure. Where gas mixtures are used, re-qualification shall be required for any changein gas mixture from that used for the welding procedure qualification. The moisturecontent of any gas or gas mixture shall correspond to a dew point -30 oC or lower. Acertificate of purity is required for all shielding gas used in welding procedurequalification.

In the field, only permitted gases as supplied by the manufacturer, in specially markedcontainers shall be used. Gas purity and quality for all containers shall be certified beforeuse. Gases that are of questionable purity and those in containers that show signs of damage shall bot be used. All containers shall be stored away from extremes of temperature.

(Addition)

328.4 Preparation for Welding

328.4.1 Cleaning

The pipe and fitting surface shall be scratch wire brush cleaned using a stainless steelwire brush for a distance of 75 mm up the bore and on the outer surface. This area shallalso be degreased prior to welding using a suitable chloride free solvent.

(Amendment)

328.4.2 End Preparation

(c) Cutting and beveling

The cutting of carbon steel pipes may be accomplished by flame cutting, plasma cuttingor mechanical methods.

If the material is a low or intermediate alloy steel machine cutting is preferred, however,if flame cutting is used the cut surface shall be dressed to remove approximately 2mm of material from the bevel by grinding.

(Amendment)


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(h) For pipe sizes greater than 2 NPS and less than 6 NPS the GTAW process is preferred for the root pass pipe and sizes greater than 6 NPS may have the rootdeposited utilizing the SMAW process.

(Addition)

(i) The SAW process shall not be used for pipe sizes below 6 NPS unless specificallyapproved by the Employer

(Addition)

(j) Butt welds made using a combination of welding processes will be permitted provided a welding procedure covering the combination is submitted to andapproved by the Employer; in particular where the root run is made by the GTAW

process, with SMAW fill and cap, the first pass with the SMAW process shall bemade, as a minimum, with 2.5mm diameter electrodes.

(Addition)

(k) No pass shall be made with electrodes in excess of 4.0mm diameter without the prior approval of the Employer.

(Addition)

(l) The maximum permitted bead widths for SMAW and SAW welding shall be:

SMAW - 2.5 to 3 times the core diameter of electrode

SAW - 7 times the diameter of the filler wire. (Addition)

(m) All GTAW process equipment shall be fitted with a high frequency starting unit.GTAW torches should also include a gas lens for improved gas shielding

(Addition)

(n) All root runs shall be made with out interruption other than the changing of electrodes/ fillers or to allow the welder to re-position himself.

All welds should be completed without intermediate cooling and pipe shall not bemoved or lifted until at least 50% of the final weld depth or 5mm (whichever thegreater) has been deposited. Where necessary, intermediate cooling under controlled conditions is permitted but only after the depth of weld required abovehas been achieved, the weld surface shall be examined by MPI before welding is

permitted to re-start. Where the material involved is P No.3 through 7, heattreatment as specified in 331.2.4 shall be applied.

An interruption is defined as break in welding exceeding 20 minutes.

Unless specifically agreed by the Employer welding and preheat maintenance shall be a continuous operation.

When interruption of welding is agreed with the Employer, the preheat may beremoved provided that slow controlled cooling of the weld area by use of insulation blankets is ensured. In any event the joint shall be inspected visually and

by MPI for linear defects prior to the recommencement of welding. Full preheatingshall always be re-established before welding is restarted.

(Addition)


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(o) All attachments shall be located and fabricated in accordance with the Contractorsdrawings approved by the Employer and the requirements of this specification.

Permanent attachments, which are made to pressure pipework, shall be welded andinspected in accordance with this specification. The NDT of the welds shall be inaccordance with Section 9 of this specification.

Temporary attachments to pressure pipework shall be minimized and shall not bemade without approval of the Employer and shall be welded using qualifiedwelding procedures and preheat as required in Clause 330 of this specification.

All temporary attachments shall be removed unless permission is obtained from theEmployer to the contrary.

Temporary attachments shall be removed by thermal cutting and/or grinding. If thermal cutting is employed, the attachments shall be cut off at a minimum distanceof 5mm from the surface of the material and then ground flush.

Temporary attachments shall not be removed by breaking the back of securing

fillet welds by hammering or any technique, which may cause mechanical damageto the surface of the fabricated pipework.

Following the removal of a temporary attachment any damaged area shall beground to merge smoothly with the original surface and the surface shall besubjected to 100% MPI and a check made that the remaining wall thickness is notless than the design wall thickness.

Scars or undercut remaining after the removal of temporary attachments shall berepaired in accordance with an Employer approved procedure. This shall be groundflush with the surface of the base metal and subjected to MPI before the joint isoffered for final inspection. Each case shall be recorded as a repair.

(Addition)

(p) Vertical down welding is not permitted (Addition)

328.5.2 Fillet and Socket Welds

(c) Whenever practicable, fillet welded joints should have a minimum of three weld passes, two of which should be showing for visual inspection.

(Addition)

328.5.3 Seal Welds

(b) Joints to be seal welded shall be made up clean and without the use of tape or anycompound. A qualified welder shall perform welding in accordance with aqualified welding procedure. The welding shall not cause damage to the threadedfitting and the seal weld shall cover all exposed threads.

(Addition)

328.5.4 Welded Branch Connections

(i) For branch connections larger than NPS 2, wherever practical, a band centeredaround the location of the proposed branch shall be ultrasonically examined toconfirm the quality of the parent pipe.


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(Addition)

328.5.5 Fabricated Laps

Not permitted. (Amendment)

328.5.6 Welding for Severe Cyclic Conditions

The weld reinforcement shall have an even finish and shall merge smoothly with the parent material without abrupt irregularity or undercutting in order to minimize stressraisers and generally be suitable for MPI. Surfaces of butt joints required to be flush shall

be finished so as not to reduce the thickness of the thinner base metal or weld metal. (Addition)

328.5.7 Proximity of Welds

Unless noted otherwise on the drawings, all pipe to pipe joints shall be butt welds. Thedistance between the toes of adjacent butt welds shall be four (4) times the nominal wall

thickness of the pipe but not less than 50 mm. Where this is not possible the Contractor shall seek approval for the specific configuration from the Employer.

Longitudinal welds shall be located so as to clear openings and external attachmentwelds. Toe to toe distance between welds shall be a minimum of one pipe diameter or 50mm whichever is the greater. Adjacent longitudinally seam welded pipes shall be locatedso that the seams are offset 90 o or 250 mm, whichever is the minimum.

Attachment of non-pressure parts by welds which cross existing main welds or for whichthe minimum nominal distance between the toe of the attachment weld and the toe of theexisting main welds or branch welds is less than the smaller of twice the thickness of themain pressure pipe or 40 mm should be avoided.

If unavoidable the area to be welded over shall be subject to 100% surface crack detectionand 100% ultrasonic examination prior to welding. After welding the welds and adjacentarea shall be similarly examined.

(Addition)

328.6 Weld Repairs

The repair rate shall be reported on a lineal basis, submitted to the Employer on a weekly basis and shall not exceed 3% during production. If this level is exceeded the Contractor shall investigate the reasons responsible for the increased repair rate and report hisfindings to the Employer with a proposed method of rectification.

Percentage Repair Rate = Defective Length Repaired Total length of welding completed

No rectification, repair or modification may be made without the approval of theEmployer.

Extent of cracks in welds or base metal shall be ascertained by use of non-destructiveinspection. The cause of cracking shall be established prior to removal and repair, a fullreport issued on cause and corrective action.


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Revision APage 20

Repairs to welds shall be limited to 30% of the weld length for a partial wall repair or 20% of the weld length for a full wall repair. When these criteria are exceeded the weldshall be completely cut out and remade.

The removal of defective areas shall be done by machining, grinding and any other method, which produces a clean, uncontaminated surface for rewelding. The resultingexcavation shall be ground to bright metal and have a contour to permit ease of repair welding. Defect removal shall be assured by MPI.

Arc air gouging only be performed on material thickness exceeding 9.5 mm. Prior tocommencement a zone not less than 150 mm wide shall be preheated to the temperaturerange indicated on the WPS.

Removal and repair of cracks in weld deposits or base metal shall be witnessed andapproved by the Employer and/or CA who reserves the right to witness the repair.

Repair welding shall be performed in accordance with the approved qualified welding procedure and the following:

(i) The crack and 50mm of sound metal beyond each end of the crack shall beremoved by a method approved by the Employer.

(ii) The welding sequence and technique shall be selected to minimize distortion andrestraint.

(iii) Preheating shall be to temperature of 50C above that specified in the relevantoriginal welding procedure.

The Employer may require further tests or simulated repairs.

Additional weld metal shall be deposited using an electrode preferably smaller than thatused for making the original weld.

Subsequent to repair, the repair areas plus 100mm on either side shall be reinspected100% by all the NDT methods prescribed for the original weld. Weld repairs shall belimited to two (2) attempts in any production weld. The Employer also reserves the rightto request complete rewelding of the joint.

The use of single pass weld repairs and the rectification of damage at temporaryattachment locations by spot weld deposition shall not be permitted.

All repairs, including those performed prior to PWHT, shall be recorded. Weld repairsshall be indicated by the use of R1, R2 or RW to indicate first or second repair and re-weld respectively.

These indicators shall be recorded as a suffix to both the weld and inspection reportnumbers. Where welds are repaired or rewelded they shall retain their original weldnumber. Inspection reports for weld repairs or rewelds shall retain their original reportnumber. All recording shall be completed on a progressive basis.

Rectification, repairs and modification shall be fully identified and documented. Thisshall include detailed inspection procedures, with an accurate description of thedimensions and locations of all defects and repairs for reference during final and/or inservice inspection.

The Contractor shall maintain an up-to-date register of all welds found to containunacceptable defects. Repairs performed both prior to and after PWHT shall be recorded


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Revision APage 21

and the register shall be freely available for inspection by the Employer at any reasonabletime. The register shall include the following information:

(i) Weld identification

(ii) Weld type and thickness

(iii) Welding procedure number

(iv) Welding process or processes(v) Welder or welding operator

(vi) Details of defect

(vii) Date welded

(viii) Date defect found

(ix) Repair procedure

(x) Date of repair and date repair accepted by Contractor/Employer (Addition)

330 Preheating

330.1 General

Preheating shall be carried out by electrical resistance or with gas burners specificallymade and shaped for the operation. Hand held torches shall not be used for preheating

purposes unless approved buy the Employer.

Electrical resistance pads are the preferred method of preheating. (Addition)

330.1.3 Temperature Verification

Preheating methods shall ensure a satisfactory temperature distribution around andthrough the material of the joint to be welded. Excessive local heating of pipe surfacesshall be avoided. Preheat and interpass temperatures shall be measured by digitalthermometer, thermocouples, thermocrayons or combination of these methods approved

by the Employer. During welding, the interpass temperature shall not exceed the valuesspecified in Table 4 of this specification.

(Addition)

330.1.4 Preheat Zone

When preheat is specified the applicable temperature shall be maintained for a minimum

distance of 75mm or 4t from the weld centerline, whichever is the greater (t=materialthickness). Lagging shall be provided on adjacent areas, if necessary, to maintain therequired degree of preheat during welding. Recommended preheats for cutting andwelding are given in Table 4 of this specification.

(Addition)

330.2 Specific Requirements

330.2.4 Interrupted Welding

If welding is interrupted then the requirements of paragraph 328.5.1 (n) shall apply.


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Revision APage 22

(Amendment)331 Heat Treatment

331.1 General

All Post Welds Heat Treatment shall be carried out in accordance with this clause.

The Contractor shall submit for approval by the Employer, PWHT procedures detailing,as a minimum, the following:

(i) Heat treatment method (furnace or local)

(ii) Heat treatment parameters

(iii) Thermocouple location and attachment method

(iv) Details of insulation etc.

(v) the type, number and location of supports installed to prevent distortion etc

PWHT should preferably be carried out in stationary furnace, but where necessary, localPWHT of circumferential welds using electrical pad type elements is permitted subject tocontrol of temperature gradients along the pipe length. The use of manually operated gastorches to carry out PWHT is not permitted.

Any furnace being used for heat treatment shall have a current furnace thermocouplecalibration certificate. Thermocouples for both furnace and local treatment shall beconnected to a suitably calibrated chart recorder, and the charts numbered with spool andweld numbers for scrutiny and endorsement by the Employer. These charts shall becomethe property of the Employer after heat treatment.

The Contractor shall inform the Employer prior to any PWHT operation in order to permit a full review and inspection to be made. All PWHT operations are subject toapproval by the Employer.

If a repair is to be performed after PWHT then further PWHT is required after the repair is performed. A Welding Procedure Qualification Test will be required by the Employer to demonstrate the effect of multiple PWHT on the design strength and notch ductility of the material.

The Contractor shall ensure that adequate structural support is installed during anyPWHT operation to prevent any sagging, warpage or distortion during the thermal cycle.

(Addition)331.3 Governing Thickness

(a) Figure 4 provides guidance on the heat treatment of branch connections.

(Amendment)

331.1.4 Heating and Cooling

(i) If a furnace post weld heat treatment is used, the furnace temperature shall notexceed 400 oC at time of loading and unloading.

(ii) The maximum rate of heating from 400 oC shall not exceed 220C per hour for pipewall thicknesses upto including 25mm and 5500/tC OR 55C per hour, whichever the greater, for pipe thicknesses greater than 25mm.


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Revision APage 23

(iii) The maximum rate of cooling from the holding temperature to 400 oC shall notexceed 275 oC per hour for pipe wall thicknesses upto and including 25mm and6875/t oC or 55 oC per hour, whichever the greater, for pipe wall thicknesses greater than 25mm.

(iv) The Contractor shall consider the need for a slow heating rate for complexfabrications

(v) The presence of low melting point materials in liquid phase in intimate contactwith the steel during heat treatment can generate detrimental effects such asintergranular penetration, embattlement or cracking. Metal or alloys of lead,lead/tin solders, zinc, cadmium, aluminium and copper shall not come into contactwith the steels during PWHT.

(vi) For welds involving existing seam welded piped in sour service a higher preheat isrequired together with a post weld hydrogen release treatment and shall be as givenin Table 4 and Table 5

331.1.6 Temperature Verification

For local PWHT, temperature measurement shall be made by thermocouples attacheddirectly to the pipe and shielded from direct radiation particularly the electric pad typeelements.

The number and location of thermocouples shall be as follows:

Pipe Size No of Thermocouples Location of Thermocouples NPS 6 2 6 and 12 oclock NPS > 6 3 4, 8 and 12 oclock

For furnace heat treatment of several spools, thermocouples shall be attached to sufficientspools including pipes at the center and bottom of the heat treatment charge to ensure

uniform temperature distribution in the furnace. (Amendment)331.2 Specific Requirements

331.2.4 Delayed Heat Treatment

If a weld in material of P-No 3 through 6 is allowed to cool to ambient temperature prior to final post weld heat treatment, intermediate post weld heat treating shall be required.

Upon completion of welding the joint shall be heat treated immediately by raising itstemperature to 300 oC and holding it there for one (1) hour per 25mm of thickness, with aminimum soak time of 30 minutes. Upon completion of the soak time the joint shall beslow cooled under insulation.

When the welds are between materials that have greater than 4% Cr and a wall thicknessgreater than 25mm the weld shall be raised, immediately after welding, to a temperaturewithin the PWHT range for that material and held there for 30 minutes after which it shall

be slow cooled under insulation.(Amendment)


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Revision APage 24

331.2.6 Local Heat Treatment

When heat treatment is applied locally, the weld shall be heated and insulated such thatthe material temperature shall exceed half the heat treatment temperature over a band of at least 2.5 rt each side of the weld center line, see Figure 5, where

r is the nominal bore radius and t is the nominal wall thickness. (Amendment)

332 Bending and Forming

332.1 General

The Contractor shall submit to the Employer for approval a full specification of the proposed bending methods, which shall include at least the following:

(i) Material type and range of size and thickness

(ii) Range of bend radii and fibre elongation

(iii)

Minimum and maximum metal temperature during bending(iv) Method of heating and maximum hold time

(v) Bending apparatus and procedure to be used

(vi) Material and procedures used to provide internal support during bending

(vii) Required heat treatment (if applicable)

(viii) Post bending non destructive testing

(ix) Post bending dimensional checks

Bends shall not be wrinkled, cracked, gouged, die-marked or buckled and shall not beexcessively scaled. Cut and shut, creased or corrugated bends are not permitted.

Bending shall be to a minimum radius of 5D (where D = nominal pipe Diameter) unlessstated otherwise on the contract drawings. Circumferential welds are not permitted on

pipe bends.

The pipe wall thickness after bending shall not less than the design wall thickness, i.e. thenominal pipe wall thickness minus the mill tolerance of the pipe. The extent and methodused for thickness checking shall be approved by the Employer.

(Addition)

332.2 Bending

332.2.3 Corrugated and Other Bends

Mitre bends shall not be used.

Pipe bends shall preferably be produced from seamless pipe, where this is not practicaland seam welded pipe is used the bending shall be by induction bending to a procedureapproved by the Employer.

(Amendment)


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Revision APage 25

332.4 Required Heat Treatment

332.4.1 Hot Bending and Forming

Additional heat treatment requirements may be specified by the Employer.(Addition)

332.4.2 Cold Bending and Forming

(a) All cold bends in P-1 and P-3 thru P-6 materials shall be subjected to heattreatment if: The increase in hardness as a result of bending exceeds 100Hv. The bend radius is less than 2D.

(Addition)

335 Assembly and Erection

335.1 General

335.1.1 Alignment

(a) Piping Distortions . The application of heat for the correction of any minor distortion shall only be undertaken with the approval of the Employer. Suchheating shall be performed in accordance with an approved procedure and themaximum temperature shall not exceed 450 oC. Spot heating techniques are not

permitted and under no circumstances shall materials be quenched to correctalignment.

(Addition)

335.2 Flanged Joints

335.2.1 Preparation for Assembly

Internal weld surfaces of butt welds at orifice flanges and other flow measuringinstruments shall be ground flush.

Machined surfaces of flanges shall be protected during and heat treatment process.(Addition)

335.2.2 Bolting Torque

Flange bolting shall be tightened evenly and sequentially to impose equal pressure on thegaskets. Refer to Flange Bolting Guideline ES.5.06.0019 for details

(Addition)

335.2.3 Bolt Length

The bolts shall be of a length that will extend entirely through but not more than 6.4mm beyond the nuts.

(Addition)


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Revision APage 26

9.0 Inspection, Examination and Testing

This section is supplementary to Chapter VI of ANSI/ASME B31.3 1996 Edition.

340 Inspection

340.1 General

The Employer shall have free access, at all times, to the fabrication and erection areas or any other part of the Contractors yard that concerns the work.

The Employer may wish to inspect materials, equipment, testing facilities and fabricationat any stage and to reject any part, which does not comply with this specification.

(Addition)

341 Examination

341.1 General

The Contractor shall formulate and implement a quality control plan complying withrequirements of this specification.

341.3 Examination Requirements

341.3.1 General

(a) For all materials, final examination shall be performed after completion of any heattreatment. An initial (non-acceptance) examination shall be performed prior toPWHT to permit any necessary repairs/rectification and inspection at the earliest

possible stage. (Amendment)

341.3.2 Acceptance Criteria

(a) The acceptance criteria for all welds shall be as per Table 5 of this specification.(Amendment)

341.4 Extent of Required Examination

The extent of examination shall be as specified in Table 6 of this specification.(Amendment)

342 Examination Personnel

342.1 Personnel Qualifications and Certification

Only personnel qualified in accordance with the requirements of ES-S-60 shall beallowed to undertake the required examinations.

(Amendment)343 Examination Procedures

All examination shall be performed to written procedures in accordance with ES-S-60and the applicable requirements of this specification and approved by the Employer, prior to the commencement of fabrication.

Examination procedures shall take account of actual weld preparations and joint access toensure full inspection coverage of the joint cross section. Limitations on the use of an


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Revision APage 27

examination procedure, which are due to joint design or fabrication sequence, shall bedefined in the procedures.

Any limitations subsequently identified at the fabrication stage shall be subject to theapproval of the Employer prior to welding the joint.

The Contractor shall furnish a dark room and viewing equipment available at any time for the Employer or the CA to review radiographs.

On welds, which are not subject to PWHT, NDT for acceptance purposes shall be performed no sooner than 48 hours after completion of welding. The Employer may relaxthis requirement to 24 hours providing the Contractor can demonstrate suitable weldingcontrols.

(Addition)344 Types of Examination

344.2 Visual Examination

It shall be the Contractors responsibility to present the pipework in a suitable conditionfor the Employers and the CAs inspection, which includes the provision of ladders andscaffolding when, required.

Final inspection shall be carried out after the removal of all slag, dirt, paint, oil or anyother foreign matter from the pipework.

The bore sides of all joints, which are accessible, shall be examined throughout their circumference, with full use being made of suitable optical instruments such asfibroscope, introscope or mirror.

(Amendment)344.3 Magnetic Particle Examination

Magnetic Particle Examination shall comply with the requirements of QGPCSpecification ES-S-60.

(Amendment)344.3.1 Method

Arc strikes outside of the weld preparations shall not be acceptable. Where these aredetermined during inspection, the arc strike shall be ground out to a smooth profile andsubjected to MPI. Where the arc strikes are caused by damaged cables the areas shall beadditionally etched to ensure freedom from contamination.

(Amendment)344.5 Radiographic Examination

Radiographic Examination shall comply with the requirements of QGPC SpecificationES-S-60.

(Amendment)

344.5.1 Method

X-ray techniques are preferred for all shop radiography of pipework upto 25mm wallthickness. However, where the use of X-rays is impractical, gamma ray isotopes may beused subject to the approval of the Employer.

In each case the technique shall be qualified using a source side image quality indicator of the wire type to DIN 45109 Part 1.


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Revision APage 28

The single wall, single image technique should be used whenever possible. Leadintensifying screens and fine grain high contrast film shall be used. Film density shall be2.0 3.0 through the thickest portion of the weld and the radiographic sensitivity shall be2% or better.

When the double wall exposure technique is unavoidable a minimum of two exposuresfor pipe sizes up to NPS 2 and a minimum of three exposures for pie sizes between NPS3 and NPS 8 shall be made. Above NPS 8 sufficient exposures shall be taken to ensurethat the weld seam is fully radiographed and that adequate overlap of film takes place.

Radiography of production welds shall use wire type IQIs with each film exposure andthis shall be placed on the source side where accessible.

(Amendment)

344.5.2 Extent of Radiography

(c) Spot radiography is not permitted. (Amendment)

(d) Where branch connections have wall thicknesses exceeding 16mm, radiographyshall be carried out (with film on the bore side) when the weld depth is similar tothe wall thickness, i.e. before the reinforcing fillet weld is applied.

(Addition)

344.6 Ultrasonic Examination

Ultrasonic Examination shall comply with the requirements of QGPC Specification ES-S-60.

(Amendment)

344.6.1 Method

The use of ultrasonic examination instead of radiographic examination may be desirableunder certain conditions of joint geometry or thickness. However its use requires thespecific approval of the Employer for each joint configuration and thickness and isnormally restricted to wall thicknesses greater than 10mm.

The Employer may specify ultrasonic examination to supplement radiography whereradiographic interpretation is difficult.

The Contractor shall employ and additional NDT techniques necessary to ensure fullevaluation of welds or clarification of defect indications.

Ultrasonic examination procedures shall be qualified for:

i) Set-in and set-on branch welds

ii) Circumferential butt welds above 100mm thick

iii) transitional welds of unequal thickness (Amendment)


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Revision APage 29

344.8 Hardness Testing

Hardness checks shall be carried out on all production welds in piping to the followingextent:

1) Hardness checks per 10m of weld or per 10 circumferential welds, whichever,yields the greater number of test (minimum one test).

2) The cap of the weld shall be removed and the surface ground smooth. Threemeasurements shall be taken on the weld and HAZ, and the average of the threeshall be taken as the result.

(Addition)344.9 Additional Examination

If the Employer or the CA has reason to believe that a defect exists in any weld or pass,including tack welds, then the Contractor when so directed, shall perform all inspectionand testing required by the Employer.

If percentage checking of welds reveals a defective weld, a further two (2) weldscompleted by the welder in question shall be selected for inspection. If these prove to be

defective, the percentage shall be increased at the Employers discretion. These additionalwelds shall not be deemed part of the percentage inspection.

If the weld is deemed defective, it shall be repaired or replaced to the satisfaction of theEmployer.

Where the Employer deems it necessary to increase the extent of testing other than for reasons of defects, the Contractor shall comply with such increased requirements and

perform this work. (Addition)

345 Testing

The Contractor shall provide the Employer with at least 24 hours notice of testing.

345.2 General Requirements for Leak Tests

345.2.7 Test Records

All tests shall be witnessed by the Employer and records on test record sheets, whichshall be signed by both the Contractor and the Employer.

(Addition)

345.3 Preparation for Leak Tests

For field welds completed between old and new material the whole line shall behydrotested at the maximum allowable operating pressure.

Differently rated systems shall be tested independently.

In situations where it is impractical to hydrotest, the reasons why shall be documentedand recorded. It shall be the Employers decision to waive hydrotest.

Prior to testing all equipment and piping shall be thoroughly cleaned of all dirt andconstruction debris or other foreign matter using potable water.


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Revision APage 30

All lines shall be flushed with water prior to testing. (Addition)

345.4 Hydrostatic Leak Tests

345.4.1 Test Fluid

The test medium shall be potable water unless stated otherwise on the contract drawingsor by the Employer.

(Amendment)

345.4.2 Test Pressure

(d) Pressurizing of the system shall be done in increments of 25% or as designated bythe Employer at the time of testing up to the test pressure of 1.5 times the design

pressure. This is to ensure that the system is stabilized and to avoid over- pressurizing. The pressure shall be maintained at each incremental stage for aminimum of two minutes or as specified by the Employer. Once the test pressurehas been attained it shall be maintained for a period of approximately one-hour

before the detailed inspection takes place.

(e) Depressurizing of the system shall be carried out at a maximum rate of 200 psig/minute to avoid vacuum collapse of any part of the system while draining thewater after the test.

(f) Check valves shall be opened to ensure that water is completely drained.

(g) A record chart shall be made of the pressures during pressurizing/depressurizing aswell as during actual testing.

(Addition)


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Revision APage 31

Table 1- Welding Procedure Qualification Test Requirements

Thickness RangeTest Method

t 25mm T > 25mm NDT Method MPI/RT MPI/RT

Transverse Tensile 2 2Bend Tests (Note 1) 4 Side 4 SideMacro & Hardness 2 2

W.M. Cap None 1W.M. Root 1 1HAZ Cap None 3

Charpy V-NotchImpact Tests

(Note 2)HAZ Root 3 3

Notes:

1) Face & Root Bends to be substituted for side bends when t < 10mm.2) Sets of HAZ Charpy specimens to be taken at FL, FL + 2 and FL + 5.

Table 2 Welding Procedure Thickness/Diameter Qualification Ranges

Nominal Pipe SizeQualification Test

Outside DiameterRange Qualified

Thickness RangeQualified

NPS 2 & Below 0.5 O.D. to O.D. As per ASME IXGreater than or equal to NPS 6 NPS 3 and above As per ASME IX

Table 3 Recommended Filler Metals For P-Numbers 1 thru 5

These recommendations are based on matching the impact toughness, the tensile properties and the chemistry of the weld deposit with the parent material. It is by nomeans exhaustive given the variety of possible application and so other electrodes mayalso be acceptable and shall be proven in the PQR testing before any application.

Steel PNumber

SMAW GMAWGTAW

FCAW SAW

C & C-Mn(-29 oC) (-46 oC) P-1

E70XXE70XX-1

ER70S-3ER70S-3

F7XX-EM12K

1/2Cr-1/2 Mo P-3 E80XX-B1 ER80X-B2L E81T1-B1 F8XX-

EXXX-F41Cr-1/2Mo1-1/4Cr-1/2Mo P-4

E80XX-B2or B2L

ER80X-B2or B2L

E8XTX-B2or B2X

F8XX-EXXX-B2or B2H

2-1/4Cr-1Mo P-5A E90XX-B3or B3LER90X-B3or B3L

E9XTX-B3or B3X

F9XX-EXXX-B3or B4

3Cr-1Mo P-5A E90XX-B3E502-XXER90X-B3ER502

E9XTX-B3E502T-1 or 2

F9XX-EXXX-B3

5Cr-1Mo P-5B E502-XX ER502 E502T-1 or 2F9XX-EXXX-B3or B6H

9Cr-1Mo P-5B ER505 E505T-1 or 2


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Revision APage 32

Table 4 Minimum Recommended Preheat Levels

Thermal Cutting

Material Material Thickness C-SteelC-Steel All 15 OCC-Mo

to 1 Cr-Mo

12.5mm

> 12.5mm

20OC

120O

C2 to 3 Cr-Mo All 150 OC5 to 9 Cr-Mo All 200 OC

Welding (New Material)

Material P-Number MaterialThickness

Preheat ( O C)

C-Steel P-1 25mm> 25mm

15OC100 OC

C-Mo P-3 12.5mm> 12.5mm

20OC100 OC

to 1 Cr-Mo P-4 12.5mm> 12.5mm

100 OC150 OC

2 to 3 Cr-Mo P-5A 12.5mm> 12.5mm

150 OC200 OC

5 to 9 Cr-Mo P-5B 200 OC

Welding (Existing Material)

Material P-NumberMaterial

Thickness Preheat (O

C)C-Steel P-1 19mm

> 19mm100 OC150 OC

C-Mo P-3 12.5mm> 12.5mm

100 OC150 OC

to 1 Cr-Mo P-4 12.5mm> 12.5mm

100 OC150 OC

2 to 3 Cr-Mo P-5A 12.5mm> 12.5mm

150 OC200 OC

5 to 9 Cr-Mo P-5B 200 OC


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Revision APage 33

Table 5- Post Weld Heat Treatment

Material P-Number MaterialThickness

Soak Temperature

(OC)Soak Time

C-Steel P-1 19mm

> 19mm

20010 OC

62010O

C

2hours2.5mins per mm

(min.. of 30minutes)

C-Mo P-3 12.5mm

> 12.5mm20010 OC65010 OC



to 1 Cr-Mo P-4 12.5mm

> 12.5mm20010 OC65010 OC



2 to 3 Cr-Mo P-5A 12.5mm

> 12.5mm20010 OC70010 OC



5 to 9 Cr-Mo P-5B All

thicknesses20010 OC




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Revision APage 34

Table 6 NDT Acceptance Criteria

Limitations for all Service ConditionsType of Defect Circumferential, Longitudinal and Branch

ConnectionsCracks Not Permitted.Lack of Fusion Not Permitted.Incomplete Penetration Not Permitted.Internal Porosity Isolated Pores

The maximum size of isolated pores shall be t or 4.0mm, whichever the lesser. If the separation of twoisolated pores is greater than 25.4mm then maximum sizeis 1/3t or 6.4mm.

For t > 50.8mm, maximum isolated pore size is 9.5mm.

Aligned Rounded IndicationsSummation of the diameters < t in any 12 t (As per ASME VIII Division 1, Appendix4)

Slag Inclusions, TungstenInclusions or ElongatedIndications.

Individual Length t/3.Individual Width 2.4mm or t/3.Cumulative Length t in any 12 t of weld length.

Undercutting Not Permitted.Surface porosity or exposed slag inclusion(for t 5mm)

Not Permitted

Surface Finish The weld shall exhibit a smooth contour and blend withthe parent material without causing stress raisers.

Concave Root Surface Not Permitted.

Reinforcement(for Fillet Welds height ismeasured from the throat)

The maximum reinforcement shall be as follows: NPS 4 and below = 1.6mm for all thicknesses.Greater than NPS 4 = 3.0mm for all thicknesses.

Internal Protrusion The maximum root penetration shall be greater than1.6mm for NPS 2 and smaller or 3mm for larger pipes.

Misalignment To be within the limits of clause 328.4.3 of thisspecification.


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Revision APage 35

Table 7 Extent of Non Destructive Testing

The minimum level of NDT is given below. This minimum level may be increased (atany level upto 100%0 if the welds are questionable or the NDT indicates excessivedefects.

Type of NDT & PercentGroup Service of LineMPI RT

A

Flare Systems (LP, MP & HP)Fuel GasHelifuelKill FluidPropaneSour CondensateSour Gas

100 100(2)

B

Closed DrainsFire Water/FightingGlycolB.A. Cascade (H.P. Side)

20 100(2)

C

Atmospheric VentsCorrosion Inhibitor Drinking Water Methanol InjectionB.A. Cascade (L.P. Side)Sour Oil

20 20(1)

D

Halon SystemHot OilOpen DrainsSanitary EffluentSlop OilUtility Water Wet Diesel Fuel

5 5(1)

Notes:

(1) 20% examination means 20 welds in 100 welds, which are, examined 100%similarly for 5% examination.

(2) Ultrasonic examination may be specified by the Employer for thickness greater than 19mm.


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10.0 Approval to Deviate

Strict compliance with this standard specification is required. Any deviation must obtain prior written approval from its custodian.

11.0 Revision History Log

A log is kept of the revision history of this document, and incorporated in theelectronic readme file (ES.5.14.010R).

12.0 Glossary

Within the context of this Design Guide the following words shall have themeanings stated:

"must/shall" - Indicates a mandatory requirement.

"should" - Indicates a preferred course of action.

"may" - Indicates one acceptable course of action.

"approval" - Indicates agreement/sanction and shall be in writing only.

QGPC - Qatar General Petroleum Corporation

Consultant - A company awarded a contract by QGPC for the company toadvise or give guidance on specific subjects. The Scope of Work may include instructions to act as an Agent for QGPC (see

Agent).

Employer - Shall mean QGPC or appointed Managing Consultant.

Contractor - The party, which entered into contract with the Employer for theexecution of activities as mentioned in a written agreement.

CertifyingAuthority (CA)

- The party which entered into contract with the Employer for thecertification of the project.

Third PartyInspection

- The impartial body appointed by the Employer possessing thenecessary competence to verity the designs, qualifications,

procedure or fabrications satisfy the specified requirements.

12.1 Abbreviations

ANSI American National Standards Institute

ASME American Society Of Mechanical Engineers

ASNT American Society For Non-Destructive Testing

ASTM American Society For Testing And Materials

AWS American Welding Society


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Revision APage 42

BS British Standard

CA Certifying Authority

GSFCAW Gas Shielded Flux Cored Arc Welding

GTAW Gas Tungsten Arc Welding

HAZ Heat Affected Zone

IQI Image Quality Indicator

LPI Liquid Penetrant Inspection

NACE National International

NDT Non-Destructive Testing

NPS Nominal Pipe Size

PCN Personnel Certification In Non Destructive Testing

PWHT Post Weld Heat Treatment

PQR Procedure Qualification Record

QA Quality Assurance

QC Quality Control

ROL Run Out Length

RT Radiographic Testing

SSFCAW Self Shielded Flux Cored Arc Welding

SMAW Shielded Metal Arc Welding

SAW Submerged Arc Welding

HV Vickers Hardness

WPS Welding Procedure Specification

YS Yield Strength

13.0 Bibliography

The following standards, codes and specifications shall, to the extent specified herein, forma part of this Design Guide. Except where a specific edition or revision is identified by dateor revision/edition number, the edition in effect at the time of the contract shall govern.

13.1 National/International Standards

ANSI B10.11 Recommended Practices For Root Pass Welding Of PipeWithout Backing

ANSI B16.9 Factory Made Wrought Steel Butt Welding Fittings

ANSI B16.25 Buttwelding Ends

ANSI B2.1 Pipe Threads (Except Dry Seal)

API Spec. 5L Specification for Line Pipe


43/43

Revision APage 43

ASME II Material Specifications

ASME V Non Destructive Testing

ASME VIII Rules for Construction of Pressure Vessels. Division 1 &Division 2

ASME IX Welding and Brazing Qualifications

ASME B31.3 Process Piping

AWS A2.4 Symbols For Welding And NDT.

AWS A3.0 Welding Terms And Definitions.

AWS A5.1 Specification For Carbon Steel Covered Arc Welding Electrodes

AWS A5.5 Specification For Low Alloy Steel Covered Arc-WeldingElectrodes.

AWS A5.17 Specification For Carbon Steel Electrodes And Fluxes For Submerged Arc Welding.

AWS A5.18 Specification For Carbon Steel Filler Metals For Gas ShieldedArc Welding.

NACE MR-01-75

Sulphide Stress Cracking Resistant Metallic Materials For OilField Equipment

ES-3 Fabrication Tolerance

ES-24 Pipe Bending Tolerance

ES-31 Fabrication Piping Assemblies

ISO 9000 Quality Management And Assurance Standards

13.2 QGPC Specifications

ES-M-11 Specification for Sour Service Materials Topsides Replacement

ES-Q-12 Engineering Standard Specification for the Painting andWrapping Metal Surfaces

ES-S-60 Specification for Non Destructive Testing of Welds