Designation:D2783−03(Reapproved2014)StandardTestMethodforMeasurementofExtreme-PressurePropertiesofLubricatingFluids(Four-BallMethod)1ThisstandardisissuedunderthefixeddesignationD2783;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoftheload-carryingpropertiesoflubricatingfluids.Thefollowingtwodeterminationsaremade:1.1.1Load-wearindex(formerlyMean-Hertzload).1.1.2Weldpointbymeansofthefour-ballextreme-pressure(EP)tester.1.2Forthedeterminationoftheload-carryingpropertiesoflubricatinggreases,seeTestMethodD2596.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.1.4ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.2.ReferencedDocuments2.1ASTMStandards:2D2596TestMethodforMeasurementofExtreme-PressurePropertiesofLubricatingGrease(Four-BallMethod)2.2ANSIStandard:B3.12MetalBalls33.Terminology3.1Definitions:3.1.1compensationline—alineofplotonlogarithmicpaper,asshowninFig.1,wherethecoordinatesarescardiameterinmillimetresandappliedloadinkilograms-force(ornewtons),obtainedunderdynamicconditions.3.1.1.1Discussion—CoordinatesforthecompensationlinearefoundinTable1,Columns1and3.3.1.1.2Discussion—Somelubricantsgivecoordinateswhichareabovethecompensationline.Knownexamplesofsuchfluidsaremethylphenylsilicone,chlorinatedmethylphenylsilicone,silphenylene,phenylether,andsomemixturesofpetroleumoilandchlorinatedparaffins.3.1.2compensationscardiameter—theaveragediameter,inmillimetres,ofthewearscaronthestationaryballscausedbytherotatingballunderanappliedloadinthepresenceofalubricant,butwithoutcausi...
