1-12_Edtn_2008.pdf

AN AMERICAN NATIO NAL STANDARDASME B31.12-2008Hydrogen Pipingand PipelinesASME Code for Pressure Piping,B31Copyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.ASME B31.12-2008Hydrogen Pipingand PipelinesASME Code for Pressure Piping,B31AN AMERICAN NATIONAL STANDARDCopyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.Date of Issuance:March 31,2009The next edition of this Code is scheduled for publication in 2011.There will be no addenda issuedto this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of this Code.The interpretations will be included with the next edition.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStandards.The Standards Committee that approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate.The proposed code or standard was madeavailable forpublic review andcomment thatprovides an opportunityfor additional publicinput from industry,academia,regulatory agencies,and the public-at-large.ASME does not“approve,”“rate,”or“endorse”any item,construction,proprietary device,or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with anyitems mentioned in this document,and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent,nor assumes any such liability.Users of a code or standard are expresslyadvised that determination of the validity of any such patent rights,and the risk of infringement of such rights,isentirely their own responsibility.Participation by federal agency representative(s)or person(s)affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the establishedASME procedures and policies,which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue,New York,NY 10016-5990Copyright 2009 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.CONTENTSForeword.ixCommittee Personnel.xPART GRGENERAL REQUIREMENTSChapter GR-1Scope and DefinitionsGR-1.1Scope.1GR-1.2Responsibilities.1GR-1.3Intent of the Code.2GR-1.4Packaged Equipment Requirements.2GR-1.5Terms and Definitions.2GR-1.6B31.12 Appendices.11GR-1.7Nomenclature.11Chapter GR-2MaterialsGR-2.1General Requirements.12GR-2.2Joining and Auxiliary Materials.26Chapter GR-3Welding,Brazing,Heat Treating,Forming,and TestingGR-3.1General.27GR-3.2Welding and Brazing.27GR-3.3Welding and Brazing Materials.30GR-3.4Construction of Weldments.30GR-3.5Preheating for Weldments.43GR-3.6Heat Treatment.43GR-3.7Specific and Alternative Heat Treat Requirements.46GR-3.8Construction of Brazements.46GR-3.9Forming of Pipe Components.48GR-3.10Testing.49Chapter GR-4Inspection,Examination,and TestingGR-4.1General.50GR-4.2Inspection.50GR-4.3Examination.50GR-4.4Personnel Qualification and Certification.51GR-4.5Extent of Required Examination and Testing.52GR-4.6Acceptance Criteria.52GR-4.7Supplementary Examination.52GR-4.8Examinations to Resolve Uncertainty.52GR-4.9Defective Components and Workmanship.52GR-4.10Testing.52GR-4.11Records.52GR-4.12NDE Definitions.52Chapter GR-5Operation and MaintenanceGR-5.1General.53GR-5.2Operation Maintenance Plan.53GR-5.3Maintenance Requirements.55GR-5.4Leakage Surveys.57GR-5.5Repair Procedures.57GR-5.6Injurious Dents and Mechanical Damage.57GR-5.7Permanent Repair of Welds With Defects.59GR-5.8Permanent Field Repair of Leaks and Nonleaking Corroded Areas.59iiiCopyright 2009 by the American Society of Mechanical E