BS-4515-1996.pdf
BRITISH STANDARD BS 4515:1996 Specification for Welding of steel pipelines on land and offshore UDC 621.791:621.643/.644-034.14 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4515:1996 This British Standard, having been prepared under the direction of the Engineering Sector Board, was published under the authority of the Standards Board and comes into effect on 15 February 1996 © BSI 07-1999 First published October 1969 Second edition March 1984 Third edition September 1995 Fourth edition February 1996 The following BSI references relate to the work on this standard: Committee reference WEE/21/7 Drafts for comment 92/78241 DC and 92/78242 DC and special announcement in BSI News January 1996 ISBN 0 580 25540 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee WEE/21, Pipework welding, to Subcommittee WEE/21/7, Field welding of pipelines, upon which the following bodies were represented: Association of Consulting Engineers British Gas plc British Institute of Non-destructive Testing Engineering Equipment and Materials Users Association Health and Safety Executive Institution of Gas Engineers International Association of Underwater Engineering Contractors Pipeline Industries Guild United Kingdom Module Constructors Association Limited United Kingdom Offshore Operators Association Water Services Association of England and Wales Welding Institute Welding Manufacturers Association (BEAMA Ltd.) Co-opted members Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4515:1996 © BSI 07-1999i Contents Page Committees responsibleInside front cover Forewordiii Section 1. General 1.1Scope1 1.2References1 1.3Definitions1 1.4Information to be supplied and items to be approved2 1.5Equipment4 1.6Welding processes4 1.7Welding consumables4 Section 2. Testing, qualification and approval of welding procedures 2.1General5 2.2Records5 2.3Welding procedure5 2.4Changes affecting qualification and approval (essential variables)5 2.5Testing of butt joints for procedure qualification12 2.6Testing of fillet welds for procedure qualification19 2.7Testing of repair welds for procedure qualification22 Section 3. Testing, qualification and approval of welders 3.1General27 3.2Butt joints27 3.3Branch connections27 3.4Fillet welds for sleeves, sockets, slip-on flanges or other attachments27 3.5Changes affecting qualification and approval (essential variables)28 3.6Non-destructive testing28 3.7Destructive testing28 3.8Retests29 3.9Records29 3.10 Mechanized welding29 Section 4. Production welding 4.1Proximity of welds30 4.2Pipe end preparation30 4.3Fusion faces30 4.4Alignment30 4.5Line-up clamps and pipe supports30 4.6Tack welds31 4.7Working clearance31 4.8Stray arcs31 4.9Weather conditions31 4.10 Preheating and post-weld heat treatment31 4.11 Branches32 4.12 Inter-run cleaning32 4.13 Partially completed joints32 Section 5. Inspection and testing of welds 5.1General33 5.2Personnel qualification33 5.3Visual inspection33 5.4Radiographic testing33 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4515:1996 ii © BSI 07-1999 Page 5.5Manual ultrasonic testing33 5.6Automatic ultrasonic testing33 5.7Magnetic particle testing33 Section 6. Acceptance and rectification of welds 6.1Non-destructive testing acceptance criteria34 6.2Rectification of welds34 Annex A (informative) Recommendations for hyperbaric arc welding37 Annex B (informative) Recommendations for brazing and aluminothermic welding of anodic bonding leads40 Annex C (informative) Proposed welding procedure specification42 Annex D (informative) Example of a record form for an MMA welder qualification test45 Annex E (informative) Guidance for establishing preheating requirements46 Annex F (informative) Example of a radiographic specification47 Figure 1 Location of repair excavations and destructive test specimens6 Figure 2 Location of test specimens13 Figure 3 Tensile test specimen16 Figure 4 Recommended locations for hardness impressions17 Figure 5 Charpy V-notch impact test specimen positions20 Figure 6 Positioning of Charpy V-notch impact specimens for procedure approval of partial penetration repair welds21 Figure 7 Preparation of fillet weld specimens23 Figure 8 Recommended locations for hardness impressions for repair test welds24 Figure B.1 Recommended locations for hardness traverses and impressions for brazing and aluminothermic welding41 Figure C.1 Example of proposed welding procedure specification42 Figure C.2 Example of welding procedure specification for production welding43 Figure C.3 As-run record of welding procedure qualification test44 Figure D.1 Example of record form for an MMA welder qualification test45 Figure E.1 Nomogram for preheating requirements46 Figure F.1 Example of a radiographic procedure specification47 Table 1 Welding procedure specification details and changes affecting approval8 Table 2 Qualified ranges of chemical analysis11 Table 3 Number of specimens for tensile tests, macro-examination and hardness survey and number of sets of specimens for Charpy tests, for procedure approval on butt joints16 Table 4 Hardness values16 Table 5 Test specimens for procedure approval tests on fillet welds19 Table 6 Number of specimens for weld repair procedure qualification23 Table 7 Diameter and thickness ranges for butt joints and branch connections28 Table 8 Acceptance criteria for welds35 List of references48 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4515:1996 © BSI 07-1999iii Foreword The revision of this British Standard has been prepared by Subcommittee WEE/21/7. It is applicable to transmission pipelines for gases, liquids or slurries, both on land and offshore. It supersedes BS 4515:1995 which is withdrawn. If welding in accordance with this British Standard is agreed with a Statutory Authority as a basis for obtaining approval to operate a pipeline, the employer will need to obtain the Authoritys agreement to any waivers of requirements. Where this Standard provides for the employer to define requirements, the Authoritys agreement may be necessary. Topics commonly involved include selecting the definition of the pipelines starting and termination points, electing to use hardness limits higher than those in Table 4, selecting the methods and frequency of non-destructive examination, electing to use Engineering Critical Assessment to derive acceptance criteria, permitting multiple attempts at repair, or permitting single run or root repairs. The employer should ensure that all relevant points have been agreed with the Statutory Authority before welding begins. In reflecting current industry practice, this British Standard places duties on, and allocates powers of approval to, the employer. In this it differs from BS EN 288-3 (under which welding procedure approval may be independent of the employer). Consequently, the term “qualification” has been retained to describe the series of actions which demonstrate that the technical requirements of this British Standard have been met during the process of welding procedure, and welder approval. It has been assumed, in the drafting of this British Standard, that the execution of its provisions will be entrusted to appropriately qualified and experienced personnel. To ensure compliance with this British Standard, the Contractors quality systems should normally be in accordance with BS EN ISO 9000. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 48, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4515:1996 © BSI 07-19991 Section 1. General 1.1 Scope This British Standard specifies requirements for the welding of carbon, carbon manganese and low alloy steel pipelines with specified minimum yield strengths not exceeding 500 N/mm2 and designed in accordance with BS 8010-2 and BS 8010-3. In addition to the definitive requirements it also requires the items detailed in 1.4 to be documented. For compliance with this standard, both the definitive requirements and the documented items have to be satisfied. The standard applies to pipes of outside diameter 21.0 mm and larger having a thickness of 3.0 mm or greater. 1.2 References 1.2.1 Normative references This standard incorporates, by dated or undated reference, provisions from other publications. These normative references are made at the appropriate places in the text and the cited publications are listed on page 48. For dated references, only the edition cited applies; any subsequent amendments to or revisions of the cited publication apply to this standard only when incorporated in the reference by amendment or revision. For undated references, the latest edition of the cited publication applies, together with any amendments. 1.2.2 Informative references This standard refers to other publications that provide information or guidance. Editions of these publications current at the time of issue of this standard are listed on page 48, but reference should be made to the latest editions. 1.3 Definitions For the purposes of this British Standard, the definitions given in BS 499-1 apply together with the following. 1.3.1 employer the owner company or the engineering agency in charge of construction NOTEThe employer may act through a consultant, an inspector or other authorized representative. 1.3.2 contractor the firm undertaking the contract and any subcontractors engaged in work covered by this standard 1.3.3 pipeline as defined in BS 8010-2 and BS 8010-3 1.3.4 joint the completed weld joining two sections of pipe, a section of pipe to a fitting, or two fittings 1.3.5 welding procedure1) a specific course of action followed in welding, including a list of materials and where necessary, tools to be used 1.3.6 welder1) the operator who performs the welding 1.3.7 approved welder a welder who has demonstrated his ability to produce welds meeting the requirements of this standard 1.3.8 root-run1) the first run deposited in the root of a multi-run weld 1.3.9 positional welding welding wherein the pipe or assembly is held stationary 1.3.10 roll welding1) a method of manipulation by rotating or rolling pipes or pipe assemblies so that all welding is carried out in or near the flat position 1.3.11 semi-automatic welding1) welding in which some of the welding variables are automatically controlled, but manual guidance is necessary 1.3.12 mechanized welding1) welding in which the welding parameters are controlled mechanically or electronically and may be manually varied during welding to maintain the required welding condition 1) Definition taken from BS 499-1. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 09:10:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4515:1996 2 © BSI 07-1999 1.3.13 sour service pipeline design conditions in which a risk of sulfide stress cracking exists NOTEThis is normally assessed using NACE MR0175 1. 1.3.14 full penetration repair any repair from the external surface of the original weld which penetrates to the bore of the pipe 1.3.15 partial penetration repair a multi-run repair from the external surface of the original weld which does not penetrate to the bore of the pipe 1.3.16 cap repair a single run repair to the external surface of the original weld 1.3.17 internal (back-weld) repair any repair from the internal surface of the original weld 1.3.18 re-repair a second attempt at repairing a defect in the same location. For qualification purposes this is a full penetration repair, testing a heat-affected zone which has received three full thermal cycles 1.3.19 qualification the series of actions necessary to demonstrate that a proposal meets the technical requirements of this British Standard 1.3.20 approval formal agreement by the employer that a qualification (or other proposal by the contractor) in accordance with this British Standard is acceptable for the proposed application 1.3.21 preliminary welding procedure specification (pWPS) a tentative welding procedure specification, which is assumed to be adequate by the manufacturer, but which has not been approved. Welding of test pieces needed for approval of a welding procedure specification has to be carried out on the basis of a preliminary welding procedure specification (pWPS) 1.4 Information to be supplied and items to be approved 1.4.1 Information to be supplied by the employer The following information to be supplied by the employer shall be fully documented and, together with the definitive requirements specified throughout the standard, shall be satisfied before a claim of compliance with the standard can be made and verified: a) whether batch testing of electrodes and filler materials is required (see 1.7.1); b) whether specific compositional controls are to be applied to the deposited weld metal (see 1.7.1); c) whether different batches of electrodes and filler materials are to be individually identifiable and completely separated (see 1.7.2); d) whether an alternative location is specified for the excavation location for the repair weld test see 2.1 b); e) whether specimens should be allowed to cool for a duration other than 24 h before testing see 2.1 c); f) whether strain ageing data and/or additional tests are required as the basis for welding procedure approval for pipe-reeling see 2.1 e); g) the type and number of re-tests required in the event of failure see 2.1 g); h) whether a lower maximum qualified carbon equivalent applies in sour service (see Table 2); i) whether any additional methods of non-destructive testing are required of butt joints see 2.5.1 b); j) the number and location of transverse tensile test specimens required for welding procedure testing on pipes up to and including 114.3 mm diameter (see 2.5.2.1); k) whether Charpy impact tests are required for welding procedure approval of butt joints (see 2.5.2.1); l) the number and location of test specimens required for Charpy impact tests on pipes of diameter 114.3 mm or less (see 2.5.2.1); m) whet
