BS 93-2008 英国协会(B.A.)螺纹.要求

BS93:2008BritishAssociation(B.A.)screwthreads–RequirementsICS21.040.30NOCOPYINGWITHOUTBSIPERMISSIONEXCEPTASPERMITTEDBYCOPYRIGHTLAWBRITISHSTANDARDLicensedCopy:ManchesterATHENS,UniversityofManchester,22/10/200822:37,UncontrolledCopy,(c)BSIPublishingandcopyrightinformationTheBSIcopyrightnoticedisplayedinthisdocumentindicateswhenthedocumentwaslastissued.©BSI2008ISBN9780580608933ThefollowingBSIreferencesrelatetotheworkonthisstandard:CommitteereferenceFME/9Draftforcomment08/30173466DCPublicationhistoryFirstpublishedMay1919Secondedition,May1951Thirdedition,September2008AmendmentsissuedsincepublicationAmd.no.DateTextaffectedBS93:2008LicensedCopy:ManchesterATHENS,UniversityofManchester,22/10/200822:37,UncontrolledCopy,(c)BSI©BSI2008•iBS93:2008ContentsForewordii1Scope12Normativereferences13Termsanddefinitionsandsymbols14ProfileofBritishAssociation(B.A.)screwthread25BasicsizesofB.A.threads36Toleranceclassesandlimitsofsizes,andtolerances,forB.A.threads37Gauges4AnnexesAnnexA(informative)BasisofsizesofB.A.threads12AnnexB(informative)BasesofallowancesandtolerancesforB.A.threads12AnnexC(informative)Effectoferrorsinpitchandflankangleontheeffectivediameter14AnnexD(informative)ApproximateinchequivalentsofB.A.threadsizes16Bibliography21ListoffiguresFigure1–BasicformofB.A.thread2Figure2–Tolerancezonesforacloseclassexternalthreadandaninternalthread5Figure3–Tolerancezonesforanormalclassexternalthreadandaninternalthread5Figure4–Exampleofeffectivediametertolerancezones(Effectivediametertolerancezonesforsize2B.A.threadsillustrated)6ListoftablesTable1–BasicsizesofBritishAssociation(B.A.)screwthreads7Table2–Limitsandtolerancesforcloseclassexternalthreads–Sizes0B.A.to10B.A.8Table3–Limitsandtolerancesfornormalclassexternalthreads–Sizes0B.A.to10B.A.9Table4–Limitsandtolerancesfornormalclassexternalthreads–Sizes11B.A.to16B.A.10Table5–Limitsandtolerancesforinternalthreads–Sizes0B.A.to16B.A.11TableB.1–Summaryoftoleranceformulae13TableD.1–BasicsizesofBritishAssociation(B.A.)screwthreads–Approximateinchequivalents16TableD.2–Limitsandtolerancesforcloseclassexternalthreads–Sizes0B.A.to10B.A.–Approximateinchequivalents17TableD.3–Limitsandtolerancesfornormalclassexternalthreads–Sizes0B.A.to10B.A.–Approximateinchequivalents18TableD.4–Limitsandtolerancesfornormalclassexternalthreads–Sizes11B.A.to16B.A.–Approximateinchequivalents19TableD.5–Limitsandtolerancesforinternalthreads–Sizes0B.A.to16B.A.–Approximateinchequivalents20SummaryofpagesThisdocumentcomprisesafrontcover,aninsidefrontcover,pagesiandii,pages1to21andabackcover.LicensedCopy:ManchesterATHENS,UniversityofManchester,22/10/200822:37,UncontrolledCopy,(c)BSIBS93:2008ii•©BSI2008ForewordPublishinginformationThisBritishStandardispublishedbyBSIandcameintoeffecton30September2008.ItwaspreparedbySubcommitteeSFTSE/1,Screwsandfastenerstechnicalspecificationcommittee,undertheauthorityofTechnicalCommitteeFME/9,Nuts,boltsandaccessories.Alistoforganizationsrepresentedonthiscommitteecanbeobtainedonrequesttoitssecretary.SupersessionThisBritishStandardsupersedesBS93:1951,whichiswithdrawn.RelationshipwithotherpublicationsThisBritishStandardisintendedforusewithBS919-2,whichspecifiesthecorrespondingscrewgauges.InformationaboutthisdocumentThisBritishStandardhasbeenfullyrevisedtobringituptodate.ThisBritishStandardspecifiestheBritishAssociation(B.A.)systemofscrewthreads,whichcomprises17gradedmetricsizesdesignatedbythenumbers0to16.Approximateinchequivalentsarealsogiven.HazardwarningsPresentationalconventionsTheprovisionsofthisstandardarepresentedinroman(i.e.upright)type.Itsrequirementsareexpressedinsentencesinwhichtheprincipalauxiliaryverbis“shall”.Commentary,explanationandgeneralinformativematerialispresentedinsmalleritalictype,anddoesnotconstituteanormativeelement.ContractualandlegalconsiderationsThispublicationdoesnotpurporttoincludeallthenecessaryprovisionsofacontract.Usersareresponsibleforitscorrectapplication.CompliancewithaBritishStandardcannotconferimmunityfromlegalobligations.WARNING.Attentionisdrawntothefactthat,withthedifferentscrewthreadformsavailable,thereisthepossibilityofamismatch,whichispotentiallyhazardous.Itistheresponsibilityofthedesigneroftheendproducttoensurethatthispossibilityisreducedtoaminimum.ForfurtherinformationonmismatchesofscrewthreadsystemsseePD6494.LicensedCopy:ManchesterATHENS,UniversityofManchester,22/10/200822:37,UncontrolledCopy,(c)BSI©BSI2008•1BS93:20081ScopeThisBritishStandardspecifieslimitsofsizes,andtolerances,forsinglestartparallelscrewthreadsofBritishAssociation(B.A.)form.Itisnotapplicabletoscrewthreadsassociatedwithinterferencefits,suchasthoseonthe“metalends”ofstudsandinthecorrespondingtappedholes.ThisBritishStandardspecifiesthefollowing:a)basicsizesforB.A.threads,sizes0B.A.to16B.A.;b)limitsofsize,andtolerances,forcloseclassandnormalclassexternalthreadsofsizes0B.A.to10B.A.;c)limitsofsize,andtolerances,fornormalclassexternalthreadsofsizes11B.A.to16B.A.;d)limitsofsize,andtolerances,forasingleclassofinternalthreadsofsizes0B.A.to16B.A.2NormativereferencesThefollowingreferenceddoc