ASTM_D_5481_-_13.pdf

Designation:D548113Standard Test Method forMeasuring Apparent Viscosity at High-Temperature andHigh-Shear Rate by Multicell Capillary Viscometer1This standard is issued under the fixed designation D5481;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.INTRODUCTIONSeveral different configurations of capillary viscometers have been successfully used for measuringthe viscosity of engine oils at the high shear rates and high temperatures that occur in engines.Thistest method covers the use of a single apparatus2at a single temperature and single shear rate toachieve greater uniformity and improved precision.1.Scope*1.1 This test method covers the laboratory determination ofhigh-temperature high-shear(HTHS)viscosity of engine oils ata temperature of 150 C using a multicell capillary viscometercontaining pressure,temperature,and timing instrumentation.The shear rate for this test method corresponds to an apparentshear rate at the wall of 1.4 million reciprocal seconds(1.4 106s1).3This shear rate has been found to decrease thediscrepancy between this test method and other high-temperature high-shear test methods3(Test Methods D4683and D4741)used for engine oil specifications.Viscosities aredetermined directly from calibrations that have been estab-lished with Newtonian oils with nominal viscosities from1.4 mPas to 5.0 mPas at 150 C.The precision has only beendetermined for the viscosity range 1.45 mPas and 5.05 mPasat 150 C for the materials listed in the precision section.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.2.1 The centiPoise(cP)is a non-SI metric unit of viscositythat is numerically equal to the milliPascal-second(mPas).1.2.2 Pounds per square inch(psi)is a non-SI unit ofpressure that is approximately equal to 6.895 kPa.These unitsare provided for information only in 6.1.1,7.3,9.1.2.1,and thetables.1.3 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:4D4683 Test Method for Measuring Viscosity of New andUsed Engine Oils at High Shear Rate and High Tempera-ture by Tapered Bearing Simulator Viscometer at 150 CD4741 Test Method for Measuring Viscosity at High Tem-perature and High Shear Rate by Tapered-Plug ViscometerD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a Material3.Terminology3.1 Definitions:3.1.1 apparent viscosity,nviscosity of a non-Newtonianliquid determined by this test method at a particular shear rateand shear stress.3.1.2 density,nmass per unit volume of the test liquid at agiven temperature.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 Oct.1,2013.Published November 2013.Originallyapproved in 1993.Last previous edition approved in 2010 as D5481 10.DOI:10.1520/D5481-13.2Manning,R.E.,and Lloyd,W.A.,“Multicell High Temperature High-ShearCapillary Viscometer,”SAE Paper 861562.Available from Society of AutomotiveEngineers(SAE),400 Commonwealth Dr.,Warrendale,PA 15096-0001,www.sae-.org.3Girshick,F.,“Non-Newtonian Fluid Dynamics in High Temperature HighShear Capillary Viscometers,”SAE Paper 922288.Available from Society ofAutomotive Engineers(SAE),400 Commonwealth Dr.,Warrendale,PA 15096-0001,www.sae.org.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 States1 3.1.2.1 DiscussionIn SI notation,the unit of density is thekilogram per cubic metre.However,for practical use,gram percubic centimetre is customarily used and is equivalent to103kg/m3.3.1.3 kinematic viscosity,nthe ratio of the viscosity to thedensity of the fluid.3.1.3.1 DiscussionKinematic viscosity is a measure of afluids resistance to flow under the force of gravity.In the SI,the unit of kinematic viscosity is the metre squared per second(m2/s);for practical use,a submultiple(millimetre squared persecond,mm2/s)is more convenient