搜索
~m25755320081582234mANSI84.1-19674January1972ACCEPTANCENOTICETheaboveIndustryStandardizationDocumentwasadoptedon4January1972andisapprovedforusebytheDOO.Theindicatedindustrygroupshavefurnishedtheclearancesrequiredbyexist-ingregulations.CopiesofthedocumentarestockedbyDoDSingleStockPoint,U.S.NavalPubli-cationsandFormsCenter,Philadelphia,Pennsylvania19120,forissuetoDoDactivitiesonly.TitleofDocument:PreferredLimitsandFitsforCylindricalPartsDateofSpecificIssueAdopted:18September1967-PlusErrataReleasingIndustryGroup:TheAmericanSocietyofMechanicalEngineersCustodians:Army-MUNavy-SHAirForce-70MilitaryCoordinatingActivity:AirForce-70ProjectNo.MISC-0596PNopartofthisdocumentmaybereproducedinanyform,inanelectronicretrievalsystemorotherwise.withoutthepriorwrittunpermissionofthepublisher.THEAMERICANSOCIETYOFMECHASICALENGINEERSCopyrrghr,Q.1967,byPrintedinU.S.A.COPYRIGHT2003;AmericanSocietyofMechanicalEngineersDocumentprovidedbyIHSLicensee=CumminsEngine/1232502100,User=,10/17/200304:52:58MDTQuestionsorcommentsaboutthismessage:pleasecalltheDocumentPolicyGroupat1-800-451-1584.--``,````,````,``,`````,,````,,-`-`,,`,,`,`,,`---USASTANDARDPreferredLimitsandFitsforCylindricalPartsUSAS84.1-1967(R1974)NoteForsoftconversionofnominaldimensionsandlimitsgiveninthisstandard,1inch=25.4mm.NationalStandard2210.1-1972,MetricPracticeGuide.ForexplanationofconversiontechniquesseeAmericanREAFFIRMED1994FORCURRENTCOMMITIEEPERSONNELPLEASESEEMMEMANUALAS-11SpOndoPTheAmericanSocietyofMechonicolEngineersTHEAMERICANSOCIETYOFMECHANICALENGINEERSUnitedEngineeringCenter345East47thStreetNewYork,N.Y.10017COPYRIGHT2003;AmericanSocietyofMechanicalEngineersDocumentprovidedbyIHSLicensee=CumminsEngine/1232502100,User=,10/17/200304:52:58MDTQuestionsorcommentsaboutthismessage:pleasecalltheDocumentPolicyGroupat1-800-451-1584.--``,````,````,``,`````,,````,,-`-`,,`,,`,`,,`---torewordTHISstandardrepresentsthelatestresultofvorkwhichbeganwiththeorganizationofSec-tionalCommitteeB4inJune1920underthenamf“SectionalCommitteeontheStandardiza-tionofPlainLimitGagesforGeneralEngineeringWork.”ThisoriginalcommitteeproducedAmericanStandardASAB4a-1925,“Tolerances,AllowancesandGagesforMetalFits,”whichwasusedinvaryingdegreeformanyyears.InDecember1930,SectionalCommitteeB4wasreorganizedandthenamechangedtothepresentform,“SectionalCommitteeontheStandardizationofAllowancesandTolerancesforCylindricalPartsandLimitGages.”Thechangeinnameindicatedasignificantshifttoamoredefiniteandsomewhatmorerestrictedmissionforthecommittee.DuringtheyearsofWorldWarIIanASAWarCommitteeformedin1943workedontheproj-ectbutproducednocompletedresults,andtheactivitywasturnedbacktoSectionalCommitteeB4.AfterthewarthesubjectwasdiscussedattheCanadianConferenceontheUnificationofEngineeringStandardsheldinOttawain1945,attendedbydelegatesfromGreatBritain,Canada,andtheUnitedStates,andagainatanotherjointmeetinginNewYorklaterinthesameyear.Thesemeetingsaresignificantbecausesince1945workinthisprojecthasbeenstronglyin-fluencedbytheseandsimilarABCconferences.Properevaluationofthepresentstandardwilldependuponanappreciationoftheimportanteffectsofprogresstowardsagreementonuni-ficationofstandardsbetweentheABCcountries.TheresultoftheactivitiesimmediatelyfollowingWorldWarIIwasAmericanStandard“LimitsandFitsforEngineeriwandManufacturing(PartI),ASAB4.1-1947.”IntheprefacetothatdocumentitwasstatedthattheABCmeetingsresultedinagreementonfivebaslcprinciples,andsincethefirstfouroftheseprinciples,withcertainminorandobviousvariations,applytothispresentstandard,itisconsideredworthwhiletorepeatthemhere.First,theremustbeacommonlanguage(definitions)throughwhichanalysesmayberecordedandconveyed.Second,atableofpreferredbasicsizeshelpsinreducingthenumberofdifferentdiameterscommonlyusedinagivensizerange.Third,preferredtolerancesandallowancesarealogicalcomple-menttopreferredsizesandshouldaidthedesignerinse!ectingstandardtolerances.Fourth,uniformityofmethodofapplyingtolerancesisessential.AdditionalABCconferenceswereheldinNewYorkinJune1952andFebruary1953.Delega-tionsfromSectionalcommitteeB4wereactiveintheseconferences,whichresultedinadraftproposalforanABCsystemofLimitsandFits,publishedasASAB4/30.TheSectionalCom-mitteeB4delegatestotheseconferencesvotedtorecommendapprovaloftheABCproposalsasthebasisforanAmericanstandardifandwhensuchastandardweredeveloped.SincethepublicationofthisstandardtherehasbeenadditionaldiscussionsatABCcon-ferencesheldinOttawainJune1960andatArdenHouse,NewYork,inSeptember1962.TherehasbeenanexpansionofdefinitionsunderASA81.7,andtheyarereflectedintherevision.TherevisedproposalwassubmittedtothesponsororganizationandtotheUSAStandardsInstitute(formerlyAmericanStandardsAssociation)forfinalapprovalasaUSAStandard.ThisapprovalwasgrantedonAugust3.1966.Thisrevision,however,wasneverpublishedasitwasnotedthatotherrhanges,agreedCOattheArdenHouseABCConference,hadnotbeenincorporatedinthestandard.Anewrevisionwasissued,andfollowingapprovalbytheUSAStandardsCommitteeB4,itwasapprovedbythesponsorandonSeptember18,1967bytheUSAStandardsInstitute.USASTANDARDThisUSAStandardi