1、Designation: D4683 10D4683 13Standard Test Method forMeasuring Viscosity of New and Used Engine Oils at HighShear Rate and High Temperature by Tapered BearingSimulator Viscometer at 150 C1This standard is issued under the fixed designation D4683; the number immediately following the designation indi
2、cates 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.This standard has been approved for use by agencies of
3、 the Department of Defense.1. Scope*1.1 This test method covers the laboratory determination of the viscosity of engine oils at 150 C and 1.0106 s1 using aviscometer having a slightly tapered rotor and stator called the Tapered Bearing Simulator (TBS) Viscometer.21.2 The Newtonian calibration oils u
4、sed to establish this test method range from approximately 1.2 mPas 1.2 mPas to 7.7mPas at 150 C. The precision has only been determined for the viscosity range 1.47 mPas to 5.09 mPas at 150 C for thematerials listed in the precision section.1.3 The non-Newtonian reference oil used to establish the
5、shear rate of 1.0106 s1 for this test method has a viscosity closelyheld to 3.55 mPas at 150 C.150 C by using the absolute viscometry of the TBS.1.4 Manual, semi-automated, and fully automated TBS viscometers were used in developing the precision statement for this testmethod.1.5 Application to petr
6、oleum products other than engine oils has not been such as base oils and formulated engine oils wasdetermined in preparing the viscometric information for this test method.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.
7、6.1 This test method uses the milliPascalsecond (mPas) as the unit of viscosity. This unit is equivalent to the centipoise (cP).1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish
8、 appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D4741 Test Method for Measuring Viscosity at High Temperature and High Shear Rate by Tapered-Plug ViscometerD5481 Test Method for Measuring Appare
9、nt Viscosity 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 LubricantsD6708 Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Te
10、st Methods that Purportto Measure the Same Property of a Material3. Terminology3.1 Definitions:1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.07 on Flow Properties.Cur
11、rent edition approved Oct. 1, 2010Oct. 1, 2013. Published November 2010November 2013. Originally approved in 1987. Last previous edition approved in 20092010as D4683D4683 10.09. DOI: 10.1520/D4683-10.10.1520/D4683-13.2 The sole source of supply of the apparatus known to the committee at this time is
12、 Tannas Co., 4800 James Savage Rd., Midland, MI 48642. If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technicalcommittee,1 which you may attend.3 For refere
13、ncedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual 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
14、 user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not 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 standar
15、d as published by ASTM is to be considered the official document.*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 States13.1.1 densityapparent viscosity, nmass per unit volume o
16、f the test liquid. In SI, the unit of density is the kilogram per cubicmetre, but, for practical use, a submultiple is more convenient. Thus, gram per cubic centimetre is customarily used and isequivalent to 10viscosity of a non-Newtonian liquid determined by this test method at a particular shear r
17、ate and shearstress.3 kg/m3.3.1.2 Newtonian oil or fluidliquid, noil or liquid that at a given temperature exhibits a constant viscosity at all shear ratesorand shear stresses.3.1.3 non-Newtonian oil or fluidliquid, noil or liquid that exhibits a viscosity that varies with changing shear stress ands
18、hear rate.3.1.4 shear raterate, nvelocity gradient in liquid flow in millimetres per second per millimetre (mm/s per mm). The SI mm)resulting from applied shear stress. The System International (SI) unit for shear rate is reciprocal seconds, s-1.3.1.4.1 DiscussionThe velocity gradient in the tapered
19、 bearing simulator viscometer is constant at any chosen rotor-stator gap and rotor speed.3.1.5 shear stressstress, nforce per unit area causing liquid flow. Theflow over unit area noted is the area over which whereviscous shear is being caused.caused; in SI, the unit of shear stress is the Pascal (P
20、a).3.1.6 viscosityviscosity, nratio of applied shear stress and the resulting rate of shear. It is sometimes called the coefficientof dynamic or absolute viscosity (in contrast to kinematic viscosity). This coefficient viscosity. Viscosity is a measure of theresistance to flow of the liquid. In the
21、SI the liquid at a given temperature. In SI, the unit of viscosity is the Pascalsecond (Pas),often conveniently expressed as milliPascalsecond (mPas), or aswhich has the English system equivalent, equivalent of thecentipoise (cP).3.1.6.1 apparent viscosityviscosity of a non-Newtonian liquid determin
22、ed by this test method at a particular shear rate or shearstress.3.1.6.2 kinematic viscosityratio 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 visco
23、sity values are thusaffected by both the dynamic viscosity (absolute viscosity) of the liquid and its density. In SI, the unit of kinematic viscosity isthe metre squared per second, often conveniently expressed as millimetre squared per second and termed the centiStoke.3.2 Definitions of Terms Speci
24、fic to This Standard:3.2.1 calibration and reference oils2, noils used to establish the viscosity-torque relationship of the TBS Viscometer at150 C from which both appropriate rotor/stator gap and the viscosity of an unknown oil is calculated.3.2.1.1 Newtonian calibration oils2, nNewtonian oils form
25、ulated to span a viscosity range suitable for generating thetorque-viscosity relationship necessary to calculate the viscosity of unknown liquids from their indicated torque values.3.2.1.2 non-Newtonian reference oil2, nNNR-03An oil specially formulated for, and critical to, this test method whichme
26、thod. The reference oil NNR-03 produces a selected value of apparent viscosity at a desired temperature and shear rate or(seeNote 1shear stress.).3.2.1.3 Newtonian reference oil2, nR-400A specially formulated Newtonian oil that has the same viscosity at 150 C asthe non-Newtonian reference oil NNR-03
27、 of 3.2.1.23.2.1.33.2.2 filter2, nspecial filter for removing particles potentially damaging to the rotor-stator interface from the injected testoil that might damage the rotor-stator interface.being injected.3.2.3 idling oil2, noxidatively stable Newtonian oil injected into the operating viscometer
28、 cell when the instrument is likelyto be operating waiting for use and held at operating temperature for more than 20 min and up to two weeks without furtherreplacement.need for replacing the idling oil.3.2.3.1 DiscussionUse of this idling oil prevents formation of stator deposits from the liquid, w
29、hich may begin to decompose after exposure timesgreater than 20 min and rotor deposits of a test oil, which if left for more than 20 min at 150 C in the operating viscometer andinstrument may begin to decompose. The idling oil this permits continuous operation of the TBS viscometer without the need
30、toshut the instrument off.off when not being used for extended periods, such as overnight or over several days, if desired.3.2.4 mechanical or digital micrometermicrometer, nmechanical or electronic device to measure or adjust the position ofthe TBS viscometer rotor in the stator.3.2.4.1 DiscussionD
31、4683 132Mechanical micrometers increase readings with rotor depth. Digital micrometers interact The digital micrometer interacts with theTBS viscometer programs.viscometers program and permits the program to maintain the rotor height at the desired shear rateusing the non-Newton reference oil of 3.2
32、.1.2.3.2.5 reciprocal torque, 1/T1/T, ndetermined value of the inverse of the torque generated by the TBS viscometer whichtorque is indicated on the console or computer depending on whether the viscometer is being used in the manual or automated(programmed) mode.3.2.6 reciprocal torque intersection,
33、 1/Ti, nrotor position on the micrometer defined by the intersection of two straight lines.These are lines generated by the reciprocal indicated torque versus rotor height for both the non-Newtonian NNR-03 and theNewtonian R-400. The intersection indicates the rotor height at which the rotor/stator
34、cell will generate 1.0106 s1 shear rate.3.2.6.1 DiscussionThis technique of accurately establishing the shear rate is called the Reciprocal Torque Intercept Method and requires the absoluteviscometry of the TBS (see 10.1.4 and Annex A2) as well as the use of both the Newtonian reference oil of 3.2.1
35、.3 and thenon-Newtonian reference oil of 3.2.1.2.3.2.7 reciprocal torque intersection, 1/Tjdesired shear rate rotor position indicated by the micrometer at the intersection of twostraight lines generated by the Reciprocal Torque Intercept Method (see 10.1.4 and AnnexA2) using both the Newtonian refe
36、renceoil of 3.2.1.2 and the non-Newtonian reference oil of 3.2.1.3.3.2.7.1 DiscussionA series of reciprocal torque values obtained at several rotor heights on both oils give linear equations whose intersectionestablishes the desired rotor height position for operation at a chosen shear rate. For thi
37、s test method the shear rate is 1.0106 s 1.3.2.7 rotor height (rotor position)position), nvertical position of the rotor relative to the stator and measured by amechanical or electronic micrometer (see 3.2.4) depending on the Model of the TBS.3.2.7.1 DiscussionFor those TBS viscometers equipped with
38、 a mechanical micrometer (Models 400, 450, 500, 600 and SS) the rotor height decreasesall TBS viscometers, the rotor decreases in position and approaches contact with the stator with increasing indicated increasingvalues on the micrometer. For those TBS viscometers equipped with electronic micromete
39、rs (Models 2100 E and 2100 EF) therotor height increases with increasing indicated values.mechanical or electronic micrometers.3.2.8 rubbing contact positionposition, nrotor height determined when the tapered rotor is brought into slipping contactwith the similarly tapered stator.3.2.9 stored positi
40、on of rotor heightheight, nrotor position with the rotor 0.50 mm above the rubbing contact position (see3.2.93.2.8) when the instrument is shut down.3.2.10 test oiloil, nany oil for which the apparent viscosity is to be determined by this test method.4. Summary of Test Method4.1 A motor turns a tape
41、red rotor closely fitted inside a matched tapered stator at a rotor-stator gap found by the ReciprocalTorque Intersection Method (see Annex A2) to provide 1.0106 s1 at 150 C, which are the test conditions of this particular testmethod. When this operating condition is established, test oils are intr
42、oduced into the gap between the spinning rotor and stationarystator either directly by the operator or indirectly by automated injection. When a test liquid is injected, the rotor experiences areactive torque to the liquids resistance to flow (viscous friction) and this torque response level is used
43、 to determine the apparentviscosity.5. Significance and Use5.1 Viscosity values at the shear rate and temperature of this test method have been indicated to be related to the viscosityproviding hydrodynamic lubrication in automotive and heavy duty engines in severe service.45.2 The viscosities of en
44、gine oils under such high temperatures and shear rates are also related to their effects on fuel efficiencyand the importance of high shear rate, high temperature viscosity has been addressed in a number of publications andpresentations.44 For a comprehensive review, see “ The Relationship Between H
45、igh- Temperature Oil Rheology and Engine Operations,” ASTM Data Series Publication 62.D4683 1336. Apparatus6.1 Tapered Bearing Simulator-Viscometer (TBS)2Apatented viscometer consisting of a motor directly connected to a slightlytapered rotor that fits into a matched tapered stator (see Fig. 1). The
46、 reaction torque of the rotor to the liquid in the cell is measuredand used to calculated viscosity. Several models of the TBS Viscometer are in use (see Annex A1 for information and pictures oflater models). All TBS models are capable of analyzing test oils at temperatures from 40 C to 200 C, but e
47、arlier models weremore limited in their upper viscosity range.NOTE 1Regarding the physics of simple flow, fluids are commonly divided into two major classes, Newtonian and non-Newtonian. Newtonian fluidsfollow Newtons equation of flow in which shear rate is directly proportional to shear stress and
48、viscosity does not change with either shear rate or shearstress at constant temperature. In contrast, the shear rate of a non-Newtonian fluid is not directly proportional to shear stress and the viscosity of sucha fluid is not constant with shear rate at a given temperature.Since the shear rate and
49、shear stress of a fluid can be directly measured if desired with the Tapered Bearing Simulator (TBS) Viscometer with nocalibration with reference fluids, the TBS is an absolute viscometer and the shear rate at which it is operating can be determined during operation andadjusted to the desired value as shown in AnnexA2.As such, the TBS provides non-Newtonian reference oils having known viscosities at whatever shearrate and temperature is desired such as the non-Newtonian Reference Oil, NNR-03
