ASTM D4741-2018 Standard Test Method for Measuring Viscosity at High Temperature and High Shear Rate by Tapered-Plug Viscometer.pdf

1、Designation: D4741 17D4741 18Standard Test Method forMeasuring Viscosity at High Temperature and High ShearRate by Tapered-Plug Viscometer1This standard is issued under the fixed designation D4741; the number immediately following the designation indicates the year oforiginal adoption or, in the cas

2、e 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This

3、 test method2 covers the laboratory determination of the viscosity of oils at 150 C and 1 106 s1 and at 100 C and1 106 s1, using high shear rate tapered-plug viscometer models BE/C or BS/C.1.2 Newtonian calibration oils are used to adjust the working gap and for calibration of the apparatus. These c

4、alibration oilscover a range from approximately 1.4 mPas to 5.9 mPas (cP) at 150 C and 4.2 mPas to 18.9 mPas (cP) at 100 C. This testmethod should not be used for extrapolation to higher viscosities than those of the Newtonian calibration oils used for calibrationof the apparatus. If it is so used,

5、the precision statement will no longer apply. The precision has only been determined for theviscosity range 1.48 mPas to 5.07 mPas at 150 C and from 4.9 mPas to 11.8 mPas at 100 C for the materials listed in theprecision section.1.3 A non-Newtonian reference oil is used to check that the working con

6、ditions are correct. The exact viscosity appropriate toeach batch of this oil is established by testing on a number of instruments in different laboratories. The agreed value for thisreference oil may be obtained from the chairman of the Coordinating European Council (CEC) Surveillance Group for CEC

7、L-36-90, or from the distributor.1.4 Applicability to products other than engine oils has not been determined in preparing this test method.1.5 This test method uses the millipascal seconds, mPas, as the unit of viscosity. For information, the equivalent cgs unit,centipoise, cP, is shown in parenthe

8、ses.The values stated in SI units are to be regarded as standard. No other units of measurementare included in this standard except those noted below.1.5.1 ExceptionThis test method uses the SI unit millipascal-second (mPas) as the unit of viscosity. (1 cP = 1 mPas.)1.6 This standard does not purpor

9、t to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.7 This internationa

10、l standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2

11、. Referenced Documents2.1 ASTM Standards:3D91 Test Method for Precipitation Number of Lubricating OilsD4683 Test Method for MeasuringViscosity of New and Used Engine Oils at High Shear Rate and HighTemperature byTaperedBearing Simulator Viscometer at 150 CD5481 Test Method for Measuring Apparent Vis

12、cosity at High-Temperature and High-Shear Rate by Multicell CapillaryViscometerD6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products and Lubricants1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuel

13、s, and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved Jan. 1, 2017June 1, 2018. Published February 2017July 2018. Originally approved in 1987. Last previous edition approved in 20132017 asD4741 13.D4741 17. DOI: 10.1520/D4741-17.10.1520/

14、D4741-18.2 This test method is technically identical to that described in CEC L-36-90 (under the jurisdiction of the CEC Engine Lubricants Technical Committee) and in IP 370.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For A

15、nnual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not

16、be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end

17、of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D6708 Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methods that Purportto Measure the Same Property of a Material2.2 Coordin

18、ating European Council (CEC) Standard:4CEC L-36-90 The Measurement of Lubricant Dynamic Viscosity under Conditions of High Shear (Ravenfield)4 Available from Coordinating European Council (CEC), Services provided by Kellen Europe,Avenue Jules Bordet 142 - 1140, Brussels, Belgium, http:/www.cectests.

19、org.D4741 1822.3 Energy Institute:5IP370 Test Method for the Measurement of Lubricant Dynamic Viscosity Under Conditions of High Shear Using the RavenfieldViscometer3. Terminology3.1 Definitions:3.1.1 apparent viscosity, nviscosity of a non-Newtonian liquid determined by this test method at a partic

20、ular shear rate andshear stress.3.1.2 density, nmass per unit volume of the test liquid at a given temperature.3.1.2.1 DiscussionIn SI notation, the unit of density is the kilogram per cubic metre. However, for practical use, gram per cubic centimetre iscustomarily used and is equivalent to 103kg/m3

21、.3.1.3 kinematic viscosity, nratio of the viscosity (dynamic, absolute) to the density of the liquid. It is a measure of theresistance to flow of a liquid where the shear stress (force causing flow) is applied by gravity. Kinematic viscosity values are thusaffected by both the dynamic viscosity (abs

22、olute viscosity) of the liquid and its density.3.1.3.1 DiscussionIn SI, the unit of kinematic viscosity is the metre squared per second, often conveniently expressed as millimetre squared persecond and termed the centiStoke.3.1.4 Newtonian oil or liquid, noil or liquid that at a given temperature ex

23、hibits a constant viscosity at all shear rates and shearstresses.3.1.5 non-Newtonian oil or liquid, noil or liquid that exhibits a viscosity that varies with changing shear stress and shear rate.3.1.6 shear rate, nvelocity gradient in liquid flow in millimetres per second per millimetre (mm/s per mm

24、) resulting fromapplied shear stress; the System International (SI) unit for shear rate is reciprocal seconds, s-1.3.1.7 shear stress, nforce per unit area causing liquid flow over the area where viscous shear is being caused; in SI, the unitof shear stress is the Pascal (Pa).3.1.8 viscosity, nratio

25、 of applied shear stress and the resulting rate of shear. It is sometimes called dynamic or absoluteviscosity (in contrast to kinematic viscosity, see 3.1.3). Viscosity is a measure of the resistance to flow of the liquid at a giventemperature.3.1.8.1 DiscussionIn SI, the unit of viscosity It is som

26、etimes called dynamic or absolute viscosity (in contrast to kinematic viscosity, see 3.1.3is thePascalsecond (Pas), often conveniently expressed as milliPascalsecond (mPas), which has the English system equivalent of thecentipoise (cP).). Viscosity is a measure of the resistance to flow of the liqui

27、d at a given temperature.3.2 Definitions of Terms Specific to This Standard:3.2.1 calibration oils, nNewtonian oils used to establish the reference framework of viscosity versus torque in this instrumentfrom which the test oil viscosity is determined.3.2.2 non-Newtonian check oil, nnon-Newtonian oil

28、 used to check that the gap or distance between the rotor and stator willproduce the desired operating shear rate of 1 106 s1.3.2.2.1 DiscussionCheck oil is an acceptable name for non-Newtonian reference oil.3.2.3 test oil, nany oil for which apparent viscosity is to be determined.4. Summary of Test

29、 Method4.1 The lubricant under test fills the annulus between a close-fitting rotor and stator. The rotor and stator have a slight, matchingtaper to allow adjustment of the gap and hence the shear rate. The rotor is spun at a known speed, and the lubricant viscosity isdetermined from measurements of

30、 the reaction torque by reference to a curve prepared using Newtonian calibration oils.5 Available from Energy Institute, 61 New Cavendish St., London, WIGW1G 7AR, U.K.U.K., http:/www.energyinst.org.D4741 1835. Significance and Use5.1 Viscosity measured under the conditions of this test method is co

31、nsidered to be representative of that at the temperaturesand shear rates but not the pressures in the journal bearings of internal combustion engines under operating conditions.5.2 The relevance of these conditions to the measurement of engine-oil viscosity has been discussed in many publications.65

32、.3 The high temperature high shear (HTHS) viscosity at this shear rate can be measured at other temperatures using thisapparatus. This is achieved by the use of a different range of Newtonian calibration fluids. . The precision has not been studiedfor any temperature or viscosity range not noted in

33、the precision section.6. Apparatus6.1 Tapered-Plug High Shear Rate Viscometer, Model BE/C (single speed) or BS/C (multi-speed).7 The viscometer uses arotating tapered plug in a matched stator.NOTE 1Model BE/C has a restricted torque range and may not be capable of measuring higher viscosities at 100

34、 C.6.2 Vacuum Extract Pipe, to ensure constant oil level. The extract pipe is supplied with all current models.6.3 Calibration Weight (supplied with instrument).6.4 Thermostatically Controlled Heating Bath, with fluid circulator. For acceptable temperature control and recovery time, thetemperature d

35、ifference between the bath and measurement head should be targeted at 4 C and shall not exceed 8 C. Thistemperature difference is influenced by the nature and rate of flow of the circulating fluid; the length and bore of the heating pipes;and the viscosity of the bath fluid.NOTE 2Bath oil with kinem

36、atic viscosity not greater than 10 mm2/s at 150 C is recommended.6.5 A means of measuring temperature is not necessary for current instruments since a precision temperature sensor is nowbuilt-in. For older instruments still in the field, a device with a precision not worse than 60.20 C is necessary.

37、6.6 The use of an ultrasonic cleaner is recommended.6.7 The manufacturer offers a package incorporating all the above and including the necessary calibration oils, reference oils,and bath oil.6.8 Vacuum Pump, with suitable liquid trap.7. Materials7.1 Newtonian Calibration Oils8CEC Reference Oils RL

38、102, RL 103, RL 104, RL 105, RL 106, and RL 107. CannonCertified Viscosity Reference Standard HT22 (nominal viscosity of 1.5 mPas at 150 C).7.2 Non-Newtonian Reference Oil8CEC Reference Oil RL 232.7.3 Washing SolventASTM precipitation naphtha as specified in Test Method D91 or a suitable replacement

39、 solvent.(WARNING Extremely flammable. Vapors may cause flash fire. See Annex A1.)7.3 Flushing SolventWhile White mineral spirit or Stoddard solvent.8. Sampling8.1 Test oils that are visually free from haze and particulates need not be filtered before evaluation. A sample shall be free ofparticles l

40、arger than 3 m. If heavy concentration of smaller particles is still visible after filtration through a filter of pore size 3 m,it is recommended to reduce their concentration by further filtration. This will reduce the possibility of the particles wedging inthe measurement gap and so causing erosio

41、n of the rotor/stator or erroneous readings. Do not filter formulated oils through poresizes below 1 m because certain lubricant additives may be removed.8.2 Used oils may also be tested in these instruments, though no precision statement is available for these materials.8.2.1 Filter used oils throu

42、gh a suitable filter such as Whatman GF/C fibreglass filter. The process of filtration is greatlyaccelerated by either warming or applying pressure. Procedures shall be such that all risk of particulate contamination is avoided.NOTE 3Suggestions have been made that the process of filtration may itse

43、lf cause a change of viscosity by the removal of particles. No doubt if thereis a very heavy concentration of particles greater than 3 m, this will be so. It is not expected or intended that this test method will be used for such oils.Evidence to date is that filtration of used oils from normal engi

44、nes in normal periods of use is acceptable. It is, however, advisable to use pressure filtrationrather than vacuum filtration so that volatile components will not be removed. No precision statement is available for used oils.6 For a comprehensive review, see “The Relationship Between High-Temperatur

45、e Oil Rheology and Engine Operation,” ASTM Data Series Publication 62 (out of print).7 The sole source of supply of the apparatus known to the committee at this time is Cannon Instrument Co., State College, PA 16803, http:/.If you are aware of alternative suppliers, please provide this information t

46、oASTM International Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee,1 which you may attend.8 Under the jurisdiction of CEC Engine Lubricants Technical Committee. Ravenfield Designs LimitedCannon Instrument Co. are distributors.D4741 1

47、849. Initial Preparation of Apparatus9.1 These instructions relate to instruments incorporating a computer, in other words, Models BE/C and BS/C. Changes fromearlier editions of this test method are those given in 10.1.5, 10.5.1, 10.5.2, 11.1.2, and 11.1.3 and the use of a vacuum extract pipeto ensu

48、re constant oil level (see 6.2).9.2 Set up the apparatus in accordance with the manufacturers manual. Attach the funnel to the side arm, using the rubbersleeve provided.NOTE 4The funnel has a larger bore than stock funnels in order to increase the rate of flow of oil samples.9.3 It is recommended th

49、at the instrument is NOTmounted in a fume cupboard since this draws in dirt particles. Local extractionover the heating bath is all that is necessary since the manufacturers bath is practically sealed.9.4 When setting up the apparatus, a torque calibration shall be performed following the instructions in the manufacturersmanual.9.5 The instrument is supplied by the manufacturer with all other functions already calibrated and set up. It is recommendedthat these other initial setti