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1-4BearingSelection(11)ShaftandhousingdesignInthedevicewherethebearingistobeembedded,attentionisrequiredtothedimensionsandaccuracydesignoftheshaftandhousingmountingpartsinordertorealizethefullperformanceofthebearing.Shaftandhousing•ShaftandhousingfinishaccuracyIftheshaftandhousingtobecombinedwiththebearingareinsufficientintermsofaccuracyandsurfaceroughness,itwillaffectthefitandthebearing'sroundnessafterassembly.Affectedroundnessleadstonoiseandshortenedlife,preventingfullperformance.Thefinishaccuracysuchasroundnessoftheshaftandhousingcanbecalculatedasgeneralcontentthroughtheradiusmethod;referenceispossibletothebasictoleranceITclassescorrespondingtothebearingbasicdimensions.FortheITvalues,seethetablebelow.Inaddition,whenmountingthebearingouterringwithinterferencewiththehousing,mountingthinballbearinginnerandouterrings,etc.,thehousingaccuracyhasgreaterinfluenceonthebearingroundness,sofurtherimprovedaccuracyisrequired.ExcerptedfromJISB0401-1Referencedimensioncategory(mm)OverUptoToleranceclass(IT)123456789101112131415161718Basictolerancevalues(μm)Basictolerancevalues(mm)60750.10.140.250.40.610.120.180.30.480.751.2900.150.220.360.580.91100.180.270.430.71.11300.210.330.520.841.31001600.250.390.6211.61.41.82.22.73.33.91.51.82.12.5-3610183036101830500.8111.21.51.51.21.51.522.52.522.52.534434456745689116891113161012151821251418222733392530364352624048587084Remark1:TolerancesIT1~4aremainlyusedforgauges,IT5~IT10mainlyforfit,andIT11~IT18fornon-fitparts.Remark2:ToleranceclassesIT14~IT18arenotusedforreferencedimensionsof1mmorbelow.58