ASME_B16.21-2021.pdf

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 21,2022The 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.CasesandinterpretationsarepublishedontheASMEwebsiteunder the Committee Pages at http:/cstools.asme.org/as they are issued.Errata to codes and standards may be posted on the ASME website under the Committee Pages to provide corrections toincorrectlypublisheditems,ortocorrecttypographicalorgrammaticalerrorsincodesandstandards.Sucherratashallbeusedon the date posted.TheCommitteePagescanbefoundathttp:/cstools.asme.org/.Thereisanoptionavailabletoautomaticallyreceiveane-mailnotification when errata are posted to a particular code or standard.This option can be found on the appropriate CommitteePage after selecting“Errata”in the“Publication Information”section.ASME is the registered trademark of The American Society of Mechanical Engineers.ThiscodeorstandardwasdevelopedunderproceduresaccreditedasmeetingthecriteriaforAmericanNationalStandards.TheStandardsCommitteethatapprovedthecodeorstandardwasbalancedtoassurethatindividualsfromcompetentandconcernedinterestshavehadanopportunityto participate.The proposed codeorstandardwasmadeavailable forpublic reviewandcommentthatprovidesanopportunityfor additional public input 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 any items mentioned in thisdocument,anddoesnotundertaketoinsureanyoneutilizingastandardagainstliabilityforinfringementofanyapplicableletterspatent,norassumeanysuchliability.Usersofacodeorstandardareexpresslyadvisedthatdeterminationofthevalidityofanysuchpatentrights,andtherisk of infringement of such rights,is entirely their own responsibility.Participation by federal agency representative(s)or person(s)affiliated with industry is not to be interpreted as government or industryendorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the established ASME proceduresand 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 EngineersTwo Park Avenue,New York,NY 10016-5990Copyright 2022 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in 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.11BAdditional 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,CastIronPipeFlangesandFlangedFittings54.1-4Gasket 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,Classes 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,Corrosion-Resistant Cast Flangesand Flanged Fittings.9iiiFOREWORDBeforethisStandardwasissued,theindividualsizesofgasketsweremadetomanydifferentsetsofdimensions,basedondifferentconceptsofadaptationandfunctionaluseonthepartofconsumersaswellasmanufacturers.Insomecases,dimensionswereshowninAmericanStandards.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