Designation:D2070−91(Reapproved2010)StandardTestMethodforThermalStabilityofHydraulicOils1ThisstandardisissuedunderthefixeddesignationD2070;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethod2isdesignedprimarilytoevaluatethethermalstabilityofhydrocarbonbasedhydraulicoilsalthoughoxidationmayoccurduringthetest.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:3D4057PracticeforManualSamplingofPetroleumandPetroleumProducts2.2CopperDevelopmentAssociationStandard4UNSC11000ElectrolyticToughPitchCopper2.3AmericanIronandSteelInstituteStandard(AISI)5W-1CarbonToolSteel3.SummaryofTestMethod3.1Abeakercontainingtestoil,copperandironrodsisplacedinanaluminumblockinanelectricgravityconvectionovenfor168hatatesttemperatureof135°C.Atthecompletionofthetest,thecopperandsteelrodsareratedvisuallyfordiscolorationandtheoilisanalyzedforthequantityofsludge.4.SignificanceandUse4.1Thermalstabilitycharacterizesphysicalandchemicalpropertychangeswhichmayadverselyaffectanoil’slubricat-ingperformance.Thistestmethodevaluatesthethermalstabilityofahydraulicoilinthepresenceofcopperandsteelat135°C.Rodcolorsaretheevaluationcriteria.Sludgevaluesarereportedforinformationalpurposes.Nocorrelationofthetesttofieldservicehasbeenmade.5.Apparatus5.1Analuminumblockwithequallyspacedholesisused.AnexampleisdescribedinFig.A1.1ofAnnexA1.5.2Electricgravityconvectionovencapableofmaintainingthealuminumblockatatesttemperatureof135°C61°C.5.2.1Calibratedthermocouple...
