1、Gas Transmission and Distribution Piping SystemsASME Code for Pressure Piping,B31AN INTE R NAT IO NAL PIPING CO D EASME B31.8-2020(Revision of ASME B31.8-2018)ASME B31.8-2020(Revision of ASME B31.8-2018)Gas Transmissionand DistributionPiping SystemsxASME Code for Pressure Piping,B31AN INTERNATIONAL
2、PIPING CODETwo Park Avenue New York,NY 10016 USAxDate of Issuance:May 31,2021The next edition of this Code is scheduled for publication in 2022.This Code will become effective 6 months after the Date ofIssuance.ASME issues written replies to inquiries concerning interpretations of technical aspects
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12、of Mechanical EngineersTwo Park Avenue,New York,NY 10016-5990Copyright 2021 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword.ixCommittee Roster.xiCorrespondence With the B31 Committee.xivIntroduction.xviSummary of Changes.xviiiGeneral Provisions and
13、Definitions.1801General.1802Scope and Intent.1803Piping Systems Definitions.2804Piping Systems Component Definitions.5805Design,Fabrication,Operation,and Testing Terms and Definitions.7806Quality Assurance.13807Training and Qualification of Personnel.13Chapter IMaterials and Equipment.15810Materials
14、 and Equipment.15811Qualification of Materials and Equipment.15812Materials for Use in Low-Temperature Applications.16813Marking.16814Material Specifications.16815Equipment Specifications.17816Transportation of Line Pipe.17817Conditions for the Reuse of Pipe.17Chapter IIWelding.20820Welding.20821Gen
15、eral.20822Preparation for Welding.20823Qualification of Procedures and Welders.21824Preheating.21825Stress Relieving.21826Weld Inspection Requirements.22827RepairorRemovalofDefectiveWeldsinPipingIntendedtoOperateatHoopStressLevelsof20%or More of the Specified Minimum Yield Strength.23Chapter IIIPipi
16、ng System Components and Fabrication Details.24830General.24831Piping System Components.24832Expansion and Flexibility.31833Design for Longitudinal Stress.32834Supports and Anchorage for Exposed Piping.35iii835Anchorage for Buried Piping.36836Liquid Removal Equipment.36Chapter IVDesign,Installation,and Testing.37840Design,Installation,and Testing.37841Steel Pipe.39842Other Materials.53843Compressor Stations.61844Pipe-Type and Bottle-Type Holders.64845Control and Limiting of Gas Pressure.65846Val
