ASTM_D_6896_-_20a.pdf

Designation:D689620aStandard Test Method forDetermination of Yield Stress and Apparent Viscosity ofUsed Engine Oils at Low Temperature1This standard is issued under the fixed designation D6896;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 measurement of the yieldstress and viscosity of engine oils after cooling at controlledrates over a period of 43 h or 45 h to a final test temperature of20 C or 25 C.The precision is stated for test temperatures20 C and 25 C.The viscosity measurements are made at ashear stress of 525 Pa over a shear rate of 0.4 s-1to 15 s-1.Thistest method is suitable for measurement of viscosities rangingfrom 4000 mPas to 400 000 mPas,and is suitable for yieldstress measurements of 7 Pa to 350 Pa.1.2 This test method is applicable for used diesel oils.Theapplicability and precision to other used or unused engine oilsor to petroleum products other than engine oils has not beendetermined.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 ExceptionThis test method uses the SI based unit ofmilliPascal second(mPas)for viscosity which is equivalent tocentiPoise(cP).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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 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:2D3829 Test Method for Predicting the Borderline PumpingTemperature of Engine OilD4684 Test Method for Determination of Yield Stress andApparent Viscosity of Engine Oils at Low TemperatureD5133 Test Method for Low Temperature,Low Shear Rate,Viscosity/Temperature Dependence of Lubricating OilsUsing a Temperature-Scanning TechniqueD8278 Specification for Digital Contact Thermometers forTest Methods Measuring Flow Properties of Fuels andLubricantsE563 Practice for Preparation and Use of an Ice-Point Bathas a Reference Temperature2.2 ISO Standards:3ISO 17025 General requirements for the competence oftesting and calibration laboratoriesISO Guide 34 General requirements for the competence ofreference material producers3.Terminology3.1 Definitions:3.1.1 apparent viscosity,nthe determined viscosity ob-tained by use of this test method.3.1.2 digital contact thermometer(DCT),nan electronicdevice consisting of a digital display and associated tempera-ture sensing probe.3.1.2.1 DiscussionThis device consists of a temperaturesensor connected to a measuring instrument;this instrumentmeasures the temperature-dependent quantity of the sensor,computes the temperature from the measured quantity,and1This 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.1,2020.Published November 2020.Originallyapproved in 2003.Last previous edition approved in 2020 as D6896 20.DOI:10.1520/D6896-20A.2For 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.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*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.1provides a digital output.This digital output goes to a digitaldisplay and/or recording device that may be internal or externalto the device.3.1.2.2 DiscussionThe devices are often referred to as a“digital thermometers,”however the term includes devices thatsense temperature by means other than being in physicalcontact with the media.3.1.2.3 DiscussionPET is an acronym for portable elec-tronic thermometers,a subset of digital contact thermometers(DCT).3.1.3 Newtonian oil or fluid,nan oil