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bearinglifeadjustmentfactorsa1,a2anda3,respec-tively.Lna=a1a2a3L10…………………………… (6)where,Lna:Correctedratinglife,106rev. : Lifeadjustmentfactorforreliability: Lifeadjustmentfactorforspeciala1a2bearingproperties a3: Lifeadjustmentfactorforoperat-ingconditionsLifeadjustmentfactorforreliabilitya1Thereliabilityofrollingbearingsisdefinedasthepro-portionofbearingshavingalifeequaltoorgreaterthanacertainspecifiedvaluewhenagroupofidenti-calbearingsareoperatedunderidenticalconditions.Withrespecttoindividualbearings,itreferstotheprobabilityofthelifeofabearingbeingequaltoorgreaterthanacertainspecifiedvalue.Thecorrectedratinglifeforareliabilityof(100-n)%canbeobtainedusingequation(6).Table2showsthevaluesofthelifeadjustmentfactora1forvariousreliabilities.LifeofoscillatingbearingThelifeofanoscillatingbearingcanbeobtainedfromequation(5).bearing,106cycles:thebasicrating Dynamicequivalentload,N2θ: Oscillatingangle,deg.(SeeFig.3)P frequencyn1min-1isTherefore,whentheoscillatinggiven,lifeasrepresentedbytotaloscillatinghourscanbeobtainedbysubstitutingn1forninequation(2)onpageA17.When2θissmall,anoilfilmcannotbeformedeasilybetweenthecontactsurfacesoftheracewayandtherollingelements.Thismaycausefrettingcorrosion.Inthiscase,pleaseconsultIKO.CP()p90θLOC: BasicLOC= ………………………………(5)where, ratinglifeofoscillating2θTable2Lifeadjustmentfactorforreliability a1a1.620.530.440.330.2110Reliability%909596979899LnL10L5L4L3L2L1Lifeadjustmentfactorforspecialbearingpropertiesa2Thebearinglifeisextendedorshortenedaccordingtothequalityofthematerial,themanufacturingtechnol-ogyofthebearinganditsinternaldesign.Forthesespecialbearinglifeproperties,thelifeiscorrectedbythelifeadjustmentfactorforspecialbearingpropertiesa2.ThetableofdimensionsforIKOBearingsshowsthevaluesofthebasicdynamicloadratingwhicharedeterminedthatbearinglifehasbeenextendedbyimprovedqualityofmaterialsandadvancesinmanufacturingtechnolo-gies.Therefore,thebearinglifeiscalculatedusingequation(6)usuallyassuminga2=1.intoconsiderationtakingfacttheFig.3OscillatingmotionCorrectedratinglifeisusedWhenarollingbearinginordinaryapplica-tions,thebasicratinglifecanbecalculatedbyequa-tions(1)and(2)mentionedpreviously.Thisbasicratinglifeappliestobearingswhichrequireareliabilityof90%,haveordinarybearingpropertiesbeingmadeofmaterialsofordinaryqualityforrollingbearings,andareusedunderordinaryoperatingcon-ditions.ittoInsomeapplications,however,obtainaratingtobearingswhichthatappliesrequirehighreliability,havespecialbearingpropertiesorareusedunderspecialoperatingconditions.ThethesespecialcasescanbecorrectedratingobtainedthefollowingequationbyusingisnecessaryfromthelifelifeforA19
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