Designation:E2412−10StandardPracticeforConditionMonitoringofIn-ServiceLubricantsbyTrendAnalysisUsingFourierTransformInfrared(FT-IR)Spectrometry1ThisstandardisissuedunderthefixeddesignationE2412;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1ThispracticecoverstheuseofFT-IRinmonitoringadditivedepletion,contaminantbuildupandbasestockdegra-dationinmachinerylubricants,hydraulicfluidsandotherfluidsusedinnormalmachineryoperation.Contaminantsmonitoredincludewater,soot,ethyleneglycol,fuelsandincorrectoil.Oxidation,nitrationandsulfonationofbasestocksaremoni-toredasevidenceofdegradation.Theobjectiveofthismoni-toringactivityistodiagnosetheoperationalconditionofthemachinebasedonfaultconditionsobservedintheoil.Mea-surementanddatainterpretationparametersarepresentedtoallowoperatorsofdifferentFT-IRspectrometerstocompareresultsbyemployingthesametechniques.1.2Thispracticeisbasedontrendinganddistributionresponseanalysisfrommid-infraredabsorptionmeasurements.Whilecalibrationtogeneratephysicalconcentrationunitsmaybepossible,itisunnecessaryorimpracticalinmanycases.Warningoralarmlimits(thepointwheremaintenanceactiononamachinebeingmonitoredisrecommendedorrequired)canbedeterminedthroughstatisticalanalysis,historyofthesameorsimilarequipment,roundrobintestsorothermethodsinconjunctionwithcorrelationtoequipmentperformance.Thesewarningoralarmlimitscanbeafixedmaximumorminimumvalueforcomparisontoasinglemeasurementorcanalsobebasedonarateofchangeoftheresponsemeasured(1).2Thispracticedescribesdistributionsbutdoesnotprecludeusingrate-of-changewarningsandalarms.NOTE1—Itisnottheintentofthispracticetoestablishorrecommendnormal,cautionary,warningoralertlimitsforanymachinery.Suchlimitsshouldbeestablishedinconjunctionwithadviceandguidancefromthemachinerymanufacturerandmaintenancegroup.1...
