ASTM_D_6895_-_21.pdf

Designation:D689521Standard Test Method forRotational Viscosity of Heavy Duty Diesel Drain Oils at100 C1This standard is issued under the fixed designation D6895;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.Scope*1.1 This test method covers the determination of the rota-tional viscosity and the shear thinning properties of heavy dutydiesel engine drain oils at 100 C,in the shear rate range ofapproximately 10 s-1to 300 s-1,in the shear stress range ofapproximately 0.1 Pa to 10 Pa and the viscosity range ofapproximately 12 mPas to 35 mPas.Rotational viscosity val-ues can be compared at a shear rate of 100 s-1by this testmethod.2,31.2 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:4D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD5967 Test Method for Evaluation of Diesel Engine Oils inT-8 Diesel EngineD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System Performance3.Terminology3.1 Definitions:3.1.1 shear rate,nthe velocity gradient perpendicular tothe direction of flow.3.1.1.1 DiscussionFor a Newtonian fluid in a concentriccylinder rotary viscometer in which the shear stress is mea-sured at the inner or outer cylinder surface and ignoring anyend effects,the shear rate is given as follows:52Ro2Ro22 Ri2(1)54Ro2tRo22 Ri2!where:=shear rate at the surface of the rotor in reciprocalseconds,s1,=angular velocity,rad/s,Ro=outer radius,mm,Ri=inner radius,mm,andt=time for one revolution of the rotor,s.3.1.1.2 DiscussionFor a fluid in a cone and plate viscom-eter in which the shear stress is measured in a controlled-stressor controlled strain mode of operation,the shear rate is givenas follows:5B(2)where:=shear rate at the surface of the rotor or stator inreciprocal seconds,s-1,=angular velocity,rad/s,B=cone angle,rad.3.1.2 shear stress,nthe force per unit area in the directionof the flow.3.1.2.1 DiscussionFor a Newtonian fluid in a concentriccylinder rotary viscometer in which the shear stress is mea-sured at the inner or outer cylinder surface and ignoring anyend effects,the shear stress is given as follows:1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.07 on Flow Properties.Current edition approved Nov.1,2021.Published November 2021.Originallyapproved in 2003.Last previous edition approved in 2017 as D6895 17.DOI:10.1520/D6895-21.2Selby,K.,“Rheology of Sootthickened Diesel Engine Oils,”SAE 981369,May 1998.3George,H.F.,Bardasz,E.A.,and Soukup,B.,“Understanding SMOT throughDesigned Experimentation Part 3:An Improved approach to Drain Oil ViscosityMeasurementsRotational Rheology,”SAE 97692,May 1997.4For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 5Tr2 Ri2h(3)where:=shear stress at the surface of the rotor or stator,Pa,Tr=torque applied to the moving fixture,Nm,Ri=inner radius,m,andh=height of the rotor,m3.1.2.2 DiscussionFor a fluid in a cone and plate viscom-eter in which the shear stress is measured in a controlled-stressor controlled-strain mode of operation,the shear stress is givenas follows:53Tr2R3(4)where:=shear stress at the surface of the rotor or stator,Pa,Tr=torque applied to the moving fixture,Nm,andR=radius of the cone.3.2 Definitions of Terms Specific to This Standard:3.2.1 maximum point time,ninstrument setting that limitsthe amount of time the instrument will maintain a constantshear stress o