Designation:D4378−13StandardPracticeforIn-ServiceMonitoringofMineralTurbineOilsforSteam,Gas,andCombinedCycleTurbines1ThisstandardisissuedunderthefixeddesignationD4378;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.INTRODUCTIONThein-servicemonitoringofturbineoilshaslongbeenrecognizedbythepower-generationindustryasbeingnecessarytoensurelongtrouble-freeoperationofturbines.Thetwomaintypesofstationaryturbinesusedforpowergenerationaresteamandgasturbines;theturbinescanbeusedasindividualturbines,orcanbeconfiguredascombinecycleturbines.Combinedcycleturbinesareoftwotypes;thefirsttypeconnectsagasturbinewithasteamturbine,withseparatelubricantcircuits,andthesecondtypemountsasteamandagasturbineonthesameshaftandhasacommonlubricantcircuit.Thelubricationrequirementsarequitesimilarbutthereareimportantdifferencesinthatgasturbineoilsaresubjectedtosignificantlyhigherlocalized“hotspot”temperaturesandwatercontaminationislesslikely.Steamturbineoilsarenormallyexpectedtolastformanyyears.Insometurbinesupto20yearsofservicelifehasbeenobtained.Gasturbineoils,bycomparison,haveashorterservicelifefrom2to5yearsdependingonseverityoftheoperatingconditions.Oneofthebenefitsofthegasturbineistheabilitytorespondquicklytoelectricalpowergenerationdispatchingrequirements.Consequently,agrowingpercentageofmoderngasturbinesarebeingusedforpeakingorcyclicduty(frequentunitstopsandstarts)thatsubjectsthelubricanttovariableconditions(veryhighdowntoambienttemperatures),whichputadditionalstressesonthelubricant.Thispracticeisdesignedtoassisttheusertovalidatetheconditionofthelubricantthroughitslifecyclebycarryingoutameaningfulprogramofsamplingandtestingofoilsinservice.Thispracticeisperformedinordertocollectdataandmonitortrendswhichsuggestanysignsoflubricantdeteriorationandtoensureasafe,reliable,andcost-effecti...
