>> P.62
Dismountingofthebearingsiscarriedoutfortheperi-odicinspectionorrepairsofmachines.Byinspectingthebearing,relatedpartsormechanisms,lubrication,etc.,importantdataisobtained.Inthesamemannerasinmounting,careshouldbetakentopreventdam-agetothebearingorotherparts.Asuitabledismountingmethodshouldbeselectedaccordingtothetypeofthebearing,fit,etc.Bearingsmountedbyinterferencefitareespeciallydifficulttodismount,anditisnecessarytogivedueconsidera-tiontothestructurearoundthebearingduringthedesignstage.DismountingofouterringOuterringsmountedbyinterferencefitaredismount-edasshowninFig.28,byscrewinginthepush-outboltsevenlythroughseveralscrewholesprovidedatplacescorrespondingtothesidefaceoftheouterring.Fig.28Guidelinesforthepressingforcewhenpressingintheinnerringtotheshaftandthepullingforcewhenpull-ingitoutareobtainedfromthefollowingequation. ………(39) }()dFK=fk ∆dfB1-2{d+2d:Pressingorpullingforce, Nwhere, K fk:Resistancefactordeterminedbythecoefficientoffriction Whenpressingininnerringtoshaft, fk=4×104 Whenpullingoutinnerringfromshaft, fk=6×104d:Borediameterofinnerring, mm∆df:Apparentinterference, mmB:Widthofinnerring, mmF:Outsidediameterofinnerring, mmforcemaybeTheactualpressinggreaterthecalculatedvalueduetomountingerrors.Whendesigningapuller,itisnecessarythatthepullerhasthestrength(rigidity)towithstandmorethan5timesthecalculatedvalue.forceorpullingthanRunningtestthemountingtocheckwhetherAftermountingthebearing,arunningtestiscarriedoutisnormal.Usually,itisfirstcheckedbymanualturning.Then,itisoperatedbypowergraduallyfromno-loadandlow-speeduptonormaloperatingconditionstocheckforabnormalities.Noisecanbecheckedbyusingasoundscopeorsimi-larinstrument.Inthistest,checksarecarriedoutforthefollowingabnormalities.1Manualturning(a)Uneventorque ……………… Impropermounting(b)Stickingandrattling … Scratchesorindentations(c)ontheracewaysurfaceIrregularnoise … Penetrationofdustorparticlesforeign2Powerrunning(a)Abnormalnoiseorvibration … Indentationsontheracewaysurface,toogreatclearance(b)Abnormaltemperature … Unsuitablelubricant,impropermounting,toosmallclearanceA59PressingforceandpullingforceDismounting