1、INTERNATICSTANDARDGeneraltolerancesPart1:TolerancesforlinearindividualtoleranceTolerancesg6n6ra!es么-orucaaofnnD-nernPartie1:TolerancespourdimtolerancesindividuellesISO2768-1:1989(E)ForewordISO(theInternationalOrganizationforStandardization)isaworldwidefederaticnationalstandardsbodies(ISOmemberbodies

2、).TheworkofpreparingInternalStandardsisnormallycarriedoutthroughISOtechnicalcommittees.Eachmebodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishestherighttoberepresentedonthatcommittee.Interration創(chuàng)organizations,gomentalandnon-governmental,inliaisonwithISO,alsotakepartinthework*collab

3、oratescloselywiththeInternatiorialElectrotechnicalCommission(IEC)cmattersofelectrotechnicalstandardization*DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatthememberbodiesforapprovalbeforetheiracceptanceasInternation白IStandantheISOCouncilTheyareapprovedinaccordaneewithISOprocedur

4、esrequiriileast75%approvalbythememberbodiesvotingInternationalStandardISO27681waspreparedbyTechnicalCommitteeISO/Limitsandfits.ThisfirsteditionofISO2768-1,togetherwithISO2768-2:1989,cancelandreISO2768:1973.ISO2768consistsofthefollowingparts,underthegeneraltitleGeneraltoleranwfQMa3nQ92合neuram么-orucaa

5、ofnnD_nemIntroductionAllfeaturesoncomponentpartthedeviationofsizeandfortheorientationandlocation)thefuiexceeded,impairthisfunction.ThetolerancingonthedrawlngsandgeometryofallfeaturesarecmentintheworkshoporintheiTheuseofgeneraltolerancesforthisprerequisiteismet5uxyw/ouwfQMa3nQ92XQmG合b&neuram么-orucnFU

6、OOaaofnB-nern2GeiWhenstworksholertoleraandmorcesshousionts.GeneralwhendnISO27Seraltoletnationaldrawingsbetweenforgedpcated,tlapplies,INTERNATIONALSTANDARDGeneraltolerancesPart1:Tolerancesforlinearandangulardimetoleranceindications1ScopeThispartofISO2768isintendedtosimplifydrawingindicationsanditspec

7、ifiesgeneraltolerancesforlinearandangulardimensionswithoutindividualtoleranceindicationsinfourtoleranceclasses.NOTE1TheconceptsbehindthegeneraltolerancingoflinearandangulardimensionsaredescribedinannexA.Itappliestothedimensionsofpartsthatareproducedbymetalremovalorpartsthatareformediromsheetmetal.NO

8、TESThesetolerancesmaybesuitableforusewithmaterialsotherthanmetalParallelInternationalStandardsexistorareplannedfe,g.seeISOforcastings.ThispartofISO2768onlyappliesforthefollowingdimensionsISO:thetcISO2768,EXAMPLEISO2768-I6RejectiUnlessothentoleranceshalabilityoftheclauseA.4LISO27681:1989(E)4.2Angular

9、dimensionsGeneraltolerancesspecifiedinangularunitscontrolonlythegeneralorientationoflinesorlineelementsofsurfaces,butnottheirformdeviations.Thegeneralorientationofthelinederivedfromtheactualsurfaceistheorientationofthecontactinglineofidealgeometricalform.Themaximumdistancebetweenthecontactinglineand

10、theactuallineshallbetheleastpossiblevalue(seeISO8015).Thepermissibledeviationsofanguladimensionsaregivenintable35IndicationsondrawingsIfgeneraltolerancesinaccordancewiththispartofISO2768shallapply,thefollowinginformationshallbeindicatedinornearthetitleblock:Table1Permissibledeviationsforlineardimens

11、ions(externalradiiandchamferheights,seeToleranceclassupto3over3upto6Permissibledeviatover6upto30over30upto120DesignationDescriptionffine0,050,05+0J+OJEmmedium0f10J+0,20,3ccoarse0,2+03650,8Vverycoarse0,51L51)Fornominalsizesbelow0,5mm,thedeviationsshallbeindicatedadjacenttotherelAnnexA(informative)Con

12、ceptsbehindgeneraltolerancingoflimwfQMa3nQ92合neuram么-orucaaofnnD_nemA.1Generaltolerancesshouldbeindicatedonthedrawingc)thebyreferencetothispartofISO2768inaccordancewithducedclause5.qualityThevaluesofgeneraltolerancescorrespondtotoleranced)theclassesofcustomaryworkshopaccuracy,theappropriatedicatedto

13、leranceclassbeingselectedandindicatedonthedrawingac-lingteacordingtotherequirementforthecomponents.toleranthepreningarA.2Abovecertaintolerancevalues,thereisusuallynogainofinspinmanufacturingeconomybyenlargingthetoleranceForexample,afeaturehavinga35mmdiametercouldbemanufac-e)puturedtoahighlevelofconf

14、ormanceinaworkshopwithnegotigcustomarymediumaccuracy.Specifyingatoleranceofworksh土1mmwouldbeofnobenefitinthisparticularworkshop,asthisahthegeneraltolerancevaluesof0,3mmwouldbequiteandthadequate.pleteHowever,if,forfunctionalreasons,afeaturerequiresasmallerTheseadtolerancevaluethanthegeneraltolerances,thenthatfeaturesufficientshouldhavethesmallertoleranceindicatedindividuallyadja-exceeded,centtothedimensiondefiningitssizeorangle.Thistypeofparticulartolerancefallsoutsidethescopeofgeneraltolerances.tolerancesIncaseswherethefunctionofafeatureallowsatoleranceThework:equaltoorlargerth