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1、胼锥想翘但猿抿镡蛾懑逊附录衲争戏灸从脓刹蜉獠回爆英语翻译色觋豹缦衫斋扃迦底说匪LUBRICATIONANDJOURNALBEARINGS夼躺柒玺嘤秭寤耘剩丶淳1Introduction鎏博痉林雠镯褰畏墩叨傥Abearingcanbedefinedasamemberspecificallydesignedtosupportmovingmachinecomponents.Themostcommonbearingapplicationisthesupportofarotatingshaftwhichistransmittingp
2、owerfromonelocationtoanother;oneexampleisthecrankshaftbearingsofautomaticengine;anotherexampleistheshaftbearingsusedalltypesofelectricmotors.Sincethereisalwaysrelativemotionbetweenabearinganditsmatingsurface,frictionisinvolved.Inmanyinstances,suchasthedesignofpull
3、eys,brakesandclutches,frictionisdesirable.However,inthecaseofbearings,thereductionoffrictionisoneofprimeconsiderations:frictionresultsinlossofpower,generationofheatandwearofmatingsurfaces.尚迮派绦遂海銮雹蝮栎冠Journalandantifrictionbearingsarethetwogeneraltypesofbearingsexis
4、tence.Journalbearingsoperatewithslidingcontact,whereasantifrictionbearingsexperiencepredominantlyrollingcontact.Theamountofslidingfrictioninjournalbearingsdependsonthesurfacefinishes,materials,slidingvelocitiesandthetypeoflubricantused.Theprinciplemotion-retarding
5、effectinantifrictionbearingsiscalledrollingresistanceratherthanrollingfriction.Thisissobecausetheresistanceofmotionisessentiallyduetothedeformationoftherollingelementsand,hence,itisnotaslidingphenomenon.Antifrictionbearingswillbeinchapter1.4.龙赓尼嘣鸣酞纨碟哨秃氲Toreducethe
6、problemsassociatedwithslidingfrictioninjournalbearings,alubricantisusedinconjunctionwithcompatiblematingmaterials.Whenselectingthelubricantandmatingmaterials,onemusttakeintoaccountbearingpressures,temperaturesandrubbingvelocities.Theprinciplefunctionofthelubricant
7、inslidingcontactbearingsistopreventphysicalcontactbetweentherubbingsurfaces.Thusthemaintenanceofanoilfilmundervaryingloads,speedsandtemperatureistheprimeconsiderationinslidingcontactbearings.抉馈咧管禀银坤速柢拮陌2TheoryofFriction氨缲徂汪樵桌庵擒捷赁孤Frictionistheresistanceonepartexer
8、tsonasecondpartwhenrelativeslidingmotionoccursorisattempted.Thusfrictiontakesplacewhenevertwosurfacesrubtogether.Thecauseoffrictionistheinevitableinterl