Designation:D4741−21StandardTestMethodforMeasuringViscosityatHighTemperatureandHighShearRatebyTapered-PlugViscometer1ThisstandardisissuedunderthefixeddesignationD4741;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thistestmethod2coversthelaboratorydeterminationoftheviscosityofoilsat150°Cand1×106s–1andat100°Cand1×106s–1,usinghighshearratetapered-plugviscometermodelsBE/CorBS/C.1.2Newtoniancalibrationoilsareusedtoadjustthework-inggapandforcalibrationoftheapparatus.Thesecalibrationoilscoverarangefromapproximately1.4mPa·sto5.9mPa·s(cP)at150°Cand4.2mPa·sto18.9mPa·s(cP)at100°C.ThistestmethodshouldnotbeusedforextrapolationtohigherviscositiesthanthoseoftheNewtoniancalibrationoilsusedforcalibrationoftheapparatus.Ifitissoused,theprecisionstatementwillnolongerapply.Theprecisionhasonlybeendeterminedfortheviscosityrange1.48mPa·sto5.07mPa·sat150°Candfrom4.9mPa·sto11.8mPa·sat100°Cforthematerialslistedintheprecisionsection.1.3Anon-Newtonianreferenceoilisusedtocheckthattheworkingconditionsarecorrect.Theexactviscosityappropriatetoeachbatchofthisoilisestablishedbytestingonanumberofinstrumentsindifferentlaboratories.TheagreedvalueforthisreferenceoilmaybeobtainedfromthechairmanoftheCoordinatingEuropeanCouncil(CEC)SurveillanceGroupforCECL-36-90,orfromthedistributor.1.4Applicabilitytoproductsotherthanengineoilshasnotbeendeterminedinpreparingthistestmethod.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandardexceptthosenotedbelow.1.5.1Exception—ThistestmethodusestheSIunitmillipascal-second(mPa·s)astheunitofviscosity.(1cP=1mPa·s.)1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistherespons...
