ASTM_D_5018_-_18.pdf

Designation:D501818Standard Test Method forShear Viscosity of Coal-Tar and Petroleum Pitches1This standard is issued under the fixed designation D5018;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 appar-ent shear viscosity of coal-tar and petroleum-based pitcheshaving a Mettler softening point(SP)range of approximately95 C to 120 C(see Test Method D3104).1.2 This test method is applicable only for rotational vis-cometers.1.3 Since this test method is based on theoretical grounds,strict adherence to details of the procedure is necessary tocomply with the theoretical requirements.1.4 The values stated in SI units are to be regarded asstandard.1.4.1 ExceptionThe values stated in conventional units(centipoise)are to be regarded as the standard for viscositymeasurement only.The SI unit is the pascal second(Pas)andone millipascal second(mPas)=one centipoise(cP);centi-poise is in cgs units.1.5 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.Specific hazard statements are given in Section 7.1.6 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:2D3104 Test Method for Softening Point of Pitches(MettlerSoftening Point Method)D4296 Practice for Sampling PitchE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE1953 Practice for Description of Thermal Analysis andRheology ApparatusE2975 Test Method for Calibration or Calibration Verifica-tion of Concentric Cylinder Rotational Viscometers3.Summary of Test Method3.1 The viscosity of a pitch,over the temperature range ofabout 40 C to 100 C above the SP of the material,isdetermined using a rotational viscometer.3.2 The recommended specifications herein are for measur-ing the apparent shear viscosity of binder pitches via aconcentric cylinder viscometer.Apparent shear viscosity is theratio of shear stress to shear rate in a unidirectional simpleshear flow field at steady state conditions.A concentriccylinder viscometer is useful for measuring the apparent shearviscosity,provided the sample temperature is adequatelycontrolled,the“end-effects”are negligible,and the gap be-tween rotor/cup is small and remains constant during the test.The extrapolated value of apparent shear viscosity at“zero”shear rate is called shear viscosity.4.Significance and Use4.1 This test method is useful as one element in establishingthe uniformity of shipments.4.2 Viscosity is also valuable for rheological characteriza-tion of binder pitches.Binder pitch imparts consistency tocarbonaceous mixes and affects their resistance to deformation.Binder pitch viscosity is important for assessing mix consis-tency and for evaluating the ease of mix extrusion or moldinginto artifacts.5.Apparatus5.1 ViscometerArotational viscometer capable of measur-ing viscosity in the range of about 5 mPas(cP)to15 000 mPas(cP);the viscometer should be equipped with theappropriate accessories to allow measurements up to about230 C.The essential instrumentation required providing theminimum rotational viscometer analytical capabilities include(see Practice E1953):1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricantsand is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels,Petroleum Coke and Carbon Material.Current edition approved June 1,2018.Published July 2018.Originally approvedin 1989.Last previous edition approved in 2015 as D5018 89(2015)1.DOI:10.1520/D5018-18.2For 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.*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)Co