外文翻译--基本额定动负荷与寿命.doc -- 5 元

英文原文BasicDynamicLoadRatingandLifeLifeRollingbearingswillsufferdamageduetovariouscausesduringservice.Damagesuchasabnormalwear,seizure,andcracksiscausedbyimproperuse,includingincorrectmounting,lackofoil,dustintrusionandsoon,andcanbeavoidedbyremedyingthesecauses.However,bearingswilleventuallybedamagedduetofatigueflakingevenifusedproperly.Whenabearingrotatesunderload,theracewaysandtherollingelementsaresubjectedtorepeatedstressesconcentratedonthepartclosetothesurface.Fatigue,therefore,occursinthesurfacelayer,producingdamageintheformofscaling.Thisiscalledflakingspalling.Whenthisoccurs,thebearingcannolongerbeused.BearingLifeBearinglifeisdefinedasthetotalnumberofrevolutionsortotalservicehoursataconstantrotationalspeedbeforeasignofthefirstflakingappearsontherollingsurfaceofracewayorrollingelements.However,evenwhenbearingsofthesamesize,structure,materialandheattreatmentaresubjectedtothesameconditions,thebearingliveswillshowvariation.Thisresultsfromthestatisticalnatureofthefatiguephenomenon.Inselectingabearing,itisincorrecttotakeanaveragelifeforallbearingsasthedesignstandard.Itismorepracticaltoconsiderabearinglifethatisreliableforthegreaterproportionofbearingsused.Therefore,thebasicratinglifedefinedinthefollowingisused.BasicratinglifeThebasicratinglifeisdefinedasthetotalnumberofrevolutionsthat90ofagroupofidenticalbearingscanbeoperatedindividuallyunderthesameconditionsfreefromanymaterialdamagecausedbyrollingfatigue.Forrotationataconstantrotationalspeed,thebasicratinglifecanberepresentedbythetotalservicehours.BasicdynamicloadratingThebasicdynamicloadratingisdefinedastheconstantradialloadinthecaseofradialbearingsortheconstantaxialloadactingalongthebearingcentralaxisinthecaseofthrustbearingsthatallowsabasicratinglifeof1,000,000revolutionsIKOCamFollowersarebearingswithastudincorporatingneedlerollersinathickwalledouterring.Thesebearingsaredesignedforouterringrotation,andhavesuperiorrotationalperformancewithasmallcoefficientoffrictionandhighloadcapacity.Asstudsalreadyhavethreadsorsteps,theyareeasytomount.CamFollowersarefollowerbearingsforcammechanismsandlinearmotionsandhavehighrigidityandhighaccuracy.Theyare,therefore,usedwidelyformachinetools,industrialrobots,electronicdevices,andOAequipment.StainlesssteelmadeCamFollowersaresuperiorincorrosionresistanceandsuitableforapplicationsinenvironmentswhereoilcannotbeusedorwatersplashed,andincleanrooms.Types1、StandardTypeCamFollowersThesearethebasictypebearingsinIKOCamFollowerseries.Modelswithstuddiametersrangingfrom3to30mmareprepared,andaresuitableforawiderangeofapplications.2、SolidEccentricStudTypeCamFollowersThestudofthesebearingsiseccentrictothecenteraxisoftheouterring.Thus,thepositionoftheouterringintheradialdirectioninrelationtothematingtracksurfacecaneasilybeadjustedbyturningthestud,andtheloaddistributiononanumberofcamfollowerouterringsusedonthesametracksurfacecanbemadeuniform.TheseareeccentriccamfollowerswithaonepiecestudthatcanbemountedinthesamemountingholesasthoseforStandardTypeCamFollowers.Eccentricityis0.25mm～0.6mm.3、EccentricTypeCamFollowersInthesebearings,aneccentriccollarisassembledwiththeCamFollowerstud,enablingtheouterringtobepositionedeasilyintheradialdirectionagainstthematingtracksurface.Eccentricityis0.4～1.5mm.4、ThrustDiskTypeCamFollowersThesebearingshavespecialresinthrustdiskwasherssuperiorinwearandheatresistancebetweentheslidingsurfacesofouterringshoulders,studheadandsideplate.Thesediskwashersreducefrictionandwearduetoaxialloadscausedbymisalignment,etc.5、CentralizedLubricationTypeCamFollowersThesebearingshaveoneortwopipethreadedholesinthestud.Thus,thisseriesissuitablewhencentralizedlubricationisrequired.6、EasyMountingTypeCamFollowersThesebearingshaveasteppedtaperedportiononthestud.WhenmountingtheCamFollower,itiseasytofixitslocationbytighteningasetscrewtothesteppedportion.Thus,thistypeissuitablewhenalargenumberofCamFollowersareusedinamachinesuchasapalletchanger.7、ClubeCamFollowerThesebearingsarelubricatedwithanewlydevelopedthermosettingsolidtypelubricantwhichfillstheinnerspaceofthebearing.Thislubricantprovideslongtermmaintenancefree.8、HeavyDutyTypeCamFollowersThesebearingsarefullcomplementtypebearingsincorporatingdoublerowsoffullcomplementcylindricalrollersintheouterring,andcanwithstandlargeradialloadsandsomeaxialloads.9、MiniatureTypeCamFollowersThesearecompactlydesignedbearings,incorporatingverythinneedlerollersinanouterringwithasmalloutsidediameter.Theyareusedinelectronicdevices,OAequipment,smallindexdevices,etc.10、InchseriesCamFollowersTwotypes,CRandCRH,areavailableintheInchseriesCamFollowers.BlackoxidefilmtreatmentismadeonCRHmodels.MaximumAllowableStaticLoadTheapplicableloadonCamFollowersis,insomecases,limitedbythebendingstrengthandshearstrengthofthestudandthestrengthoftheouterringinsteadoftheloadratingoftheneedlerollerbearing.Therefore,themaximumallowablestaticloadthatislmitedbythesestrengthsisspecified.TrackCapacityTrackcapacityisdefinedasaloadwhichcanbecontinuouslyappliedonaCamFollowerplacedonasteeltracksurfacewithoutcausinganydeformationorindentationonthetracksurfacewhentheouterringoftheCamFollowermakescontactwiththematingtracksurfaceplane.Iflubricationbetweentheouterringandthematingtracksurfaceisinsufficient,seizureand/orwearmayoccurdependingontheapplication.Therefore,attentionmustbepaidtolubricationandsurfaceroughnessofthematingtrackespeciallyforhighspeedrotationssuchascammechanisms.OperatingTemperatureRangeTheoperatingtemperaturerangeforCamFollowersis20.゜C～120゜C.However,themaximumallowabletemperatureforthefollowingtypesisdifferent.ThemaximumallowabletemperaturefortheMetricCFserieswithastuddiameterd1of4mmorlessandCFS2is110゜C,and100゜Cwhentheyarecontinuouslyoperated.Themaximumallowabletemperatureforthesealedtypewithastuddiameterd1of5mmorlessis80゜C.Mounting1、MakethecenteraxisofthemountingholeperpendiculartothemovingdirectionoftheCamFollowerandmatchthesideshoulderaccuratelywiththeseatingsurfaceindicatedbydimensionfinthetableofdimensions.Then,fixtheCamFollowerwiththenut.DonothittheflangeheadoftheCamFollowerdirectlywithahammer,etc.Thismayleadtoabearingfailuresuchasirregularrotationorcracking.2、TheIKOmarkontheflangeheadofthestudindicatesthepositionoftheoilholeontheraceway.Avoidlocatingtheoilholewithintheloadingzone.Thismayleadtoashortbearinglife.Theholelocatedinthemiddlepartofthestudperpendiculartothestudcenteraxisisusedforgreasingorlocking3、Whentighteningthenut,thetighteningtorqueshouldnotexceedthevaluesshowninthetableofdimensions.Ifthetighteningtorqueistoolarge,itispossiblethatthethreadedportionofthestudwillbebroken.Whenthereisapossibilityofloosening,aspecialnutsuchasalocknut,springwasher,orselflockingnutshouldbeused.4、InthecaseofSolidEccentricStudTypeCamFollowersandEccentricTypeCamFollowers,theouterringpositioncanbeadjustedappropriatelybyturningthestudwithascrewdriverorhexagonbarwrenchusingthescrewdriverslotorhexagonholeofthestudhead.Thestudisfixedwithanutandaspringwasher,etc.Thetighteningtorqueshouldnotexceedthevaluesofmaximumtighteningtorqueshowninthetableofdimensions.Whenshockloadsareappliedandtheadjustedeccentricityhastobeensured,itisrecommendedtomakeholesinthehousing,studandeccentriccollar,andfixthestudwithadowelpinasshowninfollowing.However,whenthestuddiameterislessthan8mmEccentriccollardiameter11mm,itisdifficulttomakeaholeinthestudbecausethestudisthroughhardened.5、IncaseofEccentricTypeCamFollowersCFE,thelengthofthemountingholeshouldbemorethan0.5mmlongerthanthedimensionofEccentriccollarwidth.6、FormountingEasyMountingTypeCamFollowers,itisrecommendedtofixthefixingscrewfromtheuppersidetothesteppedportionofthestud.InspectionofbearingCleaningofbearingWheninspectingabearingafterremoval,theappearanceofthebearingshouldberecordedfirst.Then,aftertheresidualamountoflubricantischeckedandasampleoflubricantiscollected,thebearingshouldbecleaned.Forcleaning,lightoilorkeroseneiscommonlyused.Cleaningisdividedintoroughcleaningandfinalcleaning,andwiregauzeissetasaraisedbottominacontainertopreventthebearingfromtouchingthebottomofthecontainer.Lubricatinggreaseandadheringsubstancessuchasforeignparticlesareremovedwithabrush,etc.,usingoilforroughcleaning.Careshouldbetakenduringthisprocess,becauseifthebearingisturnedwithforeignparticlesattached,theracewaysurfacesmaybescratched.Finalcleaningiscarriedoutbyturningthebearingincleaningoil.Itisdesirablethatthecleaningoiliskeptcleanbyfiltering.Immediatelyaftercleaning,thebearingmustbeprotectedagainstcorrosion.InspectionandevaluationofbearingThejudgmentastowhethertheremovedbearingisreusabledependsontheinspectionaftercleaning.Conditionsoftheracewaysurfaces,rollingelementsandfittingsurfaces,wearconditionofthecage,increaseofbearingclearance,dimensions,rotationalaccuracy,etc.shouldbecheckedfordamageandabnormalities.Theevaluationisperformedbasedontheexperiencetakingintoconsiderationthedegreeofdamage,machineperformance,importanceofthemachine,operatingconditions,perioduntilthenextinspection,andothersuchfactors.MaintenanceandinspectionMaintenanceandinspectionarecarriedouttomaintaingoodperformanceofbearingsinstalledinthemachine.Maintenanceisperformedbycheckingthemachineoperatingconditions,checkingandreplenishingorreplacingthelubricant,checkingthebearingandrelatedpartsbyperiodicdisassemblyandothersuchprocedures.Itemsforinspectionofarunningbearinginamachineincludethebearingtemperature,noise,vibrationandconditionoflubricant.Damage,causesandcorrectiveactionRollingbearingscangenerallybeusedfullyuptotheirrollingfatiguelifeiftheyareproperlyselected,mounted,operatedandmaintained.However,theymayactuallybedamagedearlierthantheirexpectedlifetimescreatingproblemsoraccidents.Commoncausesofdamageincludeimpropermountingorhandling,insufficientlubricationandpenetrationofforeignparticles.Itmaybedifficulttodeterminetheexactcauseofaproblembycheckingonlythedamagedbearing.Theconditionsofthemachinebeforeandaftertheoccurrenceofthedamage,thelocationandtheoperatingandambientconditionsofthebearing,thestructurearoundthebearing,etc.shouldalsobeexamined.Itthenbecomespossibletoassessthecauseofthedamagebylinkingtheconditionsofthedamagedbearingtotheprobablecausesarisingfromthemachineoperation,andtopreventtherecurrenceofsimilarproblems.