ASTM_D_7098_-_08_2015.pdf

Designation:D709808(Reapproved 2015)Standard Test Method forOxidation Stability of Lubricants by Thin-Film OxygenUptake(TFOUT)Catalyst B1,2This standard is issued under the fixed designation D7098;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1This test method covers the oxidation stability oflubricants by thin-film oxygen uptake(TFOUT)Catalyst B.This test method evaluates the oxidation stability of petroleumproducts,and it was originally developed as a screening test toindicate whether a given re-refined base stock could beformulated for use as automotive engine oil3(see Test MethodD4742).The test is run at 160 C in a pressure vessel underoxygen pressure,and the sample contains a metal catalystpackage,a fuel catalyst,and water to partially simulate oilconditions in an operating engine.In addition,the test methodhas since been found broadly useful as an oxidation test ofpetroleum products.41.2 The applicable range of the induction time is from a fewminutes up to several hundred minutes or more.However,therange of induction times used for developing the precisionstatements in this test method was from 40 min to 280 min.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3.1 ExceptionPressure units are provided in psig,anddimensions are provided in inches in AnnexA1 and AnnexA2,because these are the industry accepted standard and theapparatus is built according to the figures shown.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:5A314 Specification for Stainless Steel Billets and Bars forForgingB211 Specification for Aluminum and Aluminum-AlloyRolled or Cold Finished Bar,Rod,and WireD664 Test Method for Acid Number of Petroleum Productsby Potentiometric TitrationD1193 Specification for Reagent WaterD2272 Test Method for Oxidation Stability of Steam Tur-bine Oils by Rotating Pressure VesselD4742 Test Method for Oxidation Stability of GasolineAutomotive Engine Oils by Thin-Film Oxygen Uptake(TFOUT)E1 Specification for ASTM Liquid-in-Glass ThermometersE144 Practice for Safe Use of Oxygen Combustion Vessels3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 break pointthe precise point of time at which rapidoxidation of the oil begins.3.1.2 oxidation induction timethe time until the oil beginsto oxidize at a relatively rapid rate as indicated by the decreaseof oxygen pressure.3.1.3 oxygen uptakeoxygen absorbed by oil as a result ofoil oxidation.4.Summary of Test Method4.1 The test oil is mixed in a glass container with four otherliquids used to simulate engine conditions:(1)an oxidized/nitrated fuel component(Annex A3),(2)a mixture of soluble1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.09.0G on Oxidation Testing of Engine Oils.Current edition approved Oct.1,2015.Published December 2015.Originallyapproved in 2005.Last previous edition approved in 2008 as D7098 081.DOI:10.1520/D7098-08R15.2While Catalyst B can be used for testing oxidation stability of many lubricanttypes,the mixture of fuel,nitro-paraffin,and catalyst components used in this testmethod simulates the Sequence IIIE Engine Test.Test results on several ASTMreference oils have been found to correlate with Sequence IIIE engine tests in hoursfor a 375%viscosity increase.(See Ku,Chia-Soon,Pei,Patrick T.,and Hsu,Stephen M.,“A Modified Thin-Film Oxygen Uptake Test(TFOUT)for theEvaluation of Lubricant Stability in ASTM Sequence IIIE Test,SAE TechnicalPaper Series 902121,Tulsa,OK,Oct.22-25,1990.)3Ku,C.S.and Hsu,S.M.,“A Thin Film Uptake Test for the Evaluation ofAutomotive Lubricants,”Lubrication Engineering,40,2,1984,pp.7583.4Selby,Theodore W.,“Oxidation Studies with a Modified Thin-Film OxygenUptake Test”,SAE Technical Paper Series 872127,Toronto,Ontario,Nov.2-5,1987.5For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 metal naphthenates(lead,iron,manganese,and tin naphthen-ates(AnnexA4),(3)a nitro-paraffinic compound,and(4)TypeI reagent water.4.2 The glass container holding the oil mixture is placed ina pressure vessel equipped with a pressur