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附录英语翻译LUBRICATIONANDJOURNALBEARINGS1INTRODUCTIONABEARINGCANBEDEFINEDASAMEMBERSPECIFICALLYDESIGNEDTOSUPPORTMOVINGMACHINECOMPONENTSTHEMOSTCOMMONBEARINGAPPLICATIONISTHESUPPORTOFAROTATINGSHAFTWHICHISTRANSMITTINGPOWERFROMONELOCATIONTOANOTHER；ONEEXAMPLEISTHECRANKSHAFTBEARINGSOFAUTOMATICENGINE；ANOTHEREXAMPLEISTHESHAFTBEARINGSUSEDALLTYPESOFELECTRICMOTORSSINCETHEREISALWAYSRELATIVEMOTIONBETWEENABEARINGANDITSMATINGSURFACE,FRICTIONISINVOLVEDINMANYINSTANCES,SUCHASTHEDESIGNOFPULLEYS,BRAKESANDCLUTCHES,FRICTIONISDESIRABLEHOWEVER,INTHECASEOFBEARINGS,THEREDUCTIONOFFRICTIONISONEOFPRIMECONSIDERATIONSFRICTIONRESULTSINLOSSOFPOWER,GENERATIONOFHEATANDWEAROFMATINGSURFACESJOURNALANDANTIFRICTIONBEARINGSARETHETWOGENERALTYPESOFBEARINGSEXISTENCEJOURNALBEARINGSOPERATEWITHSLIDINGCONTACT,WHEREASANTIFRICTIONBEARINGSEXPERIENCEPREDOMINANTLYROLLINGCONTACTTHEAMOUNTOFSLIDINGFRICTIONINJOURNALBEARINGSDEPENDSONTHESURFACEFINISHES,MATERIALS,SLIDINGVELOCITIESANDTHETYPEOFLUBRICANTUSEDTHEPRINCIPLEMOTIONRETARDINGEFFECTINANTIFRICTIONBEARINGSISCALLEDROLLINGRESISTANCERATHERTHANROLLINGFRICTIONTHISISSOBECAUSETHERESISTANCEOFMOTIONISESSENTIALLYDUETOTHEDEFORMATIONOFTHEROLLINGELEMENTSAND,HENCE,ITISNOTASLIDINGPHENOMENONANTIFRICTIONBEARINGSWILLBEINCHAPTER14TOREDUCETHEPROBLEMSASSOCIATEDWITHSLIDINGFRICTIONINJOURNALBEARINGS,ALUBRICANTISUSEDINCONJUNCTIONWITHCOMPATIBLEMATINGMATERIALSWHENSELECTINGTHELUBRICANTANDMATINGMATERIALS,ONEMUSTTAKEINTOACCOUNTBEARINGPRESSURES,TEMPERATURESANDRUBBINGVELOCITIESTHEPRINCIPLEFUNCTIONOFTHELUBRICANTINSLIDINGCONTACTBEARINGSISTOPREVENTPHYSICALCONTACTBETWEENTHERUBBINGSURFACESTHUSTHEMAINTENANCEOFANOILFILMUNDERVARYINGLOADS,SPEEDSANDTEMPERATUREISTHEPRIMECONSIDERATIONINSLIDINGCONTACTBEARINGS2THEORYOFFRICTIONFRICTIONISTHERESISTANCEONEPARTEXERTSONASECONDPARTWHENRELATIVESLIDINGMOTIONOCCURSORISATTEMPTEDTHUSFRICTIONTAKESPLACEWHENEVERTWOSURFACESRUBTOGETHERTHECAUSEOFFRICTIONISTHEINEVITABLEINTERLOCKINGOFTHETINYIRREGULARITIESOFTHETWOMATINGSURFACESAFORCEISREQUIREDTODEFORMTHETINYPEAKSANDVALLEYSTOPERMITMOTIONWHENABLOCKOFWEIGHTWRESTSONAHORIZONTALFIXEDSURFACE,AFORCEPISAPPLIEDTOTHEBLOCKINITIALLY,PEQUALSZERO,BUTITSVALUECONSTANTLYINCREASESASAFUNCTIONOFTIMEDUETOFRICTION,AFORCEFISCREATEDBETWEENBLOCKANDFIXEDSURFACETHEDIRECTIONOFTHEFRICTIONALFORCE,F,ISOPPOSITETHATOFP,BECAUSEFRICTIONALWAYSOPPOSESMOTIONORATTEMPTEDMOTIONALSONOTETHATTHENORMALFORCE,N,ACTINGPERPENDICULARTOTHEMATINGSURFACEISEQUALANDOPPOSITETOTHEWEIGHT,W,OFTHEBLOCKROLLINGCONTACTBEARINGSTHECONCERNOFAMACHINEDESIGNERWITHBALLANDROLLERBEARINGSISFIVEFOLDASFOLLOWSALIFEINRELATIONTOLOAD；BSTIFFNESS,IEDEFLECTIONSUNDERLOAD；CFRICTION；DWEAR；ENOISEFORMODERATELOADSANDSPEEDSTHECORRECTSELECTIONOFASTANDARDBEARINGONTHEBASISOFLOADRATINGWILLBECOMEIMPORTANTWHERELOADSAREHIGH,ALTHOUGHTHISISUSUALLYOFLESSMAGNITUDETHANTHATOFTHESHAFTSOROTHERCOMPONENTSASSOCIATEDWITHTHEBEARINGWHERESPEEDSAREHIGHSPECIALCOOLINGARRANGEMENTSBECOMENECESSARYWHICHMAYINCREASEFRICTIONALDRAGWEARISPRIMARILYASSOCIATEDWITHTHEINTRODUCTIONOFCONTAMINANTS,ANDSEALINGARRANGEMENTSMUSTBECHOSENWITHREGARDTOTHEHOSTILITYOFTHEENVIRONMENTBECAUSETHEHIGHQUALITYANDLOWPRICEOFBALLANDROLLERBEARINGSDEPENDSONQUANTITYPRODUCTION,THETASKOFTHEMACHINEDESIGNERBECOMESONEOFSELECTIONRATHERTHANDESIGNROLLINGCONTACTBEARINGSAREGENERALLYMADEWITHSTEELWHICHISTHROUGHHARDENEDTOABOUT900HV,ALTHOUGHINMANYMECHANISMSSPECIALRACESARENOTPROVIDEDANDTHEINTERACTINGSURFACESAREHARDENEDTOABOUT600HVITISNOTSURPRISINGTHAT,OWINGTOTHEHIGHSTRESSESINVOLVED,APREDOMINANTFORMOFFAILURESHOULDBEMETALFATIGUE,ANDAGOODDEALOFWORKISBASEDONACCEPTEDVALUESOFLIFEANDITISGENERALPRACTICEINTHEBEARINGINDUSTRYTODEFINETHELOADCAPACITYOFTHEBEARINGASTHATVALUEBELOWWHICH90PERCENTOFABATCHWILLEXCEEDALIFEOFONEMILLIONREVOLUTIONSNOTWITHSTANDINGTHEFACTTHATRESPONSIBILITYFORTHEBASICDESIGNOFBALLANDROLLERBEARINGSRESTSWITHTHEBEARINGMANUFACTURER,THEMACHINEDESIGNERMUSTFORMACORRECTAPPRECIATIONOFTHEDUTYTOBEPERFORMEDBYTHEBEARINGANDBECONCERNEDNOTONLYWITHBEARINGSELECTIONBUTWITHTHECONDITIONSFORCORRECTINSTALLATIONTHEFITOFTHEBEARINGRACESONTOTHESHAFTORONTOTHEHOUSINGSISOFCRITICALIMPORTANCEBECAUSEOFTHEIRCOMBINEDEFFECTONTHEINTERNALCLEARANCEOFTHEBEARINGASWELLASPRESERVINGTHEDESIREDDEGREEOFINTERFERENCEFITINADEQUATEINTERFERENCECANINDUCESERIOUSTROUBLEFROMFRETTINGCORROSIONTHEINNERRACEISFREQUENTLYLOCATEDAXIALLYBYABUTTINGAGAINSTASHOULDERARADIUSATTHISPOINTISESSENTIALFORTHEAVOIDANCEOFSTRESSCONCENTRATIONANDBALLRACESAREPROVIDEDWITHARADIUSORCHAMFERTOALLOWSPACEFORTHISWHERELIFEISNOTTHEDETERMININGFACTORINDESIGN,ITISUSUALTODETERMINEMAXIMUMLOADINGBYTHEAMOUNTTOWHICHABEARINGWILLDEFLECTUNDERLOADTHUSTHECONCEPTOF“STATICLOADCARRYINGCAPACITY”ISUNDERSTOODTOMEANTHELOADTHATCANBEAPPLIEDTOABEARING,WHICHISEITHERSTATIONARYORSUBJECTTOSLIGHTSWIVELINGMOTIONS,WITHOUTIMPAIRINGITSRUNNINGQUALITIESFORSUBSEQUENTROTATIONALMOTIONTHISHASBEENDETERMINEDBYPRACTICALEXPERIENCEASTHELOADWHICHWHENAPPLIEDTOABEARINGRESULTSINATOTALDEFORMATIONOFTHEROLLINGELEMENTDIAMETERTHISWOULDCORRESPONDTOAPERMANENTDEFORMATIONOF00025MMFORABALL25MMINDIAMETERTHESUCCESSFULFUNCTIONINGOFMANYBEARINGSDEPENDSUPONPROVIDINGTHEMWITHADEQUATEPROTECTIONAGAINSTTHEI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