1、AN AM E R IC AN NAT IO NAL STANDARDASME B16.21-2021(Revision of ASME B16.21-2016)NonmetallicFlat Gaskets for Pipe FlangesASME B16.21-2021(Revision of ASME B16.21-2016)NonmetallicFlat Gaskets forPipe FlangesAN AMERICAN NATIONAL STANDARDTwo Park Avenue New York,NY 10016 USAxDate of Issuance:January 21
2、,2022The next edition of this Standard is scheduled for publication in 2026.ASME issues written replies to inquiries concerning interpretations of technical aspects of this Standard.Periodically certainactionsoftheASMEB16CommitteemaybepublishedasCases.CasesandinterpretationsarepublishedontheASMEwebs
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10、y 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 EngineersTwo Park Avenue,New York,NY 10016-5990Copyright 2022 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted i
11、n U.S.A.CONTENTSForeword.ivCommittee Roster.vCorrespondence With the B16 Committee.viSummary of Changes.viiiList of Changes in Record Number Order.ix1Scope.12General.13Materials.14Dimensions and Tolerances.25Markings.2Mandatory AppendixIReferences.10Nonmandatory AppendicesAQuality System Program.11B
12、Additional Reference.12Tables4.1-1Gasket Dimensions for ASME B16.1 Class 25,Cast Iron Pipe Flanges and Flanged Fittings.34.1-2Gasket Dimensions for ASME B16.1 Class 125,Cast Iron Pipe Flanges and Flanged Fittings.44.1-3FlatRingGasketDimensionsforASMEB16.1Class250,CastIronPipeFlangesandFlangedFitting
13、s54.1-4Gasket Dimensions for ASME B16.5 Class 150,Pipe Flanges and Flanged Fittings.64.1-5Flat Ring Gasket Dimensions for ASME B16.5,Pipe Flanges and FlangedFittings,Classes 300,400,600,and 900.74.1-6Full Face Gasket Dimensions for ASME B16.24,Cast Copper Alloy Pipe Flanges andFlanged Fittings,Class
14、es 150 and 300.74.1-7FlatRingGasketDimensionsforASMEB16.47SeriesA,LargeDiameterSteelFlanges,Classes150,300,400,and 600.84.1-8Flat Ring Gasket Dimensions for ASME B16.47 Series B,Large Diameter Steel Flanges,Classes 75,150,300,400,and 600.84.1-9Full Face Gasket Dimensions for MSS SP-51 Class 150LW,Co
15、rrosion-Resistant Cast Flangesand Flanged Fittings.9iiiFOREWORDBeforethisStandardwasissued,theindividualsizesofgasketsweremadetomanydifferentsetsofdimensions,basedondifferentconceptsofadaptationandfunctionaluseonthepartofconsumersaswellasmanufacturers.Insomecases,dimensionswereshowninAmericanStandar
16、ds.Tostandardizegasketsizes,theStandardsandSpecificationsCommitteeofthe MechanicalPacking Association(MPA)started work on a standard fornonmetallic or cut gaskets forbronze,iron,and steel pipe flanges.Dimensions of gaskets being used were collected,and a basic design philosophy for sizing was formulated by theCommittee.This was the result of extensive field research experience and accepted standard user requirements.Theprocedure that followed was to dimension the gasket for each type and size of
