1、Designation: D5133 05 (Reapproved 2011)Standard Test Method forLow Temperature, Low Shear Rate, Viscosity/TemperatureDependence of Lubricating Oils Using a Temperature-Scanning Technique1This standard is issued under the fixed designation D5133; the number immediately following the designation indic
2、ates 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. Scope1.1 This test method covers the measurement of
3、the appar-ent viscosity of engine oil at low temperatures.1.2 A shear rate of approximately 0.2 s-1is produced atshear stresses below 100 Pa. Apparent viscosity is measuredcontinuously as the sample is cooled at a rate of 1C/h over therange 5 to 40C, or to the temperature at which the viscosityexcee
4、ds 40 000 mPas (cP).1.3 The measurements resulting from this test method areviscosity, the maximum rate of viscosity increase (GelationIndex), and the temperature at which the Gelation Indexoccurs.1.4 Applicability to petroleum products other than engineoils has not been determined in preparing this
5、 test method.1.5 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.6 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
6、establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D341 Practice for Viscosity-Temperature Charts for LiquidPetroleum ProductsD3829 Test Method for Predicting the Borderline PumpingTemp
7、erature of Engine OilD4684 Test Method for Determination of Yield Stress andApparent Viscosity of Engine Oils at Low Temperature3. Terminology3.1 Definitions:3.1.1 apparent viscosity, nthe viscosity obtained by use ofthis test method.3.1.1.1 DiscussionSee 3.1.6 for definition of viscosity andunits.3
8、.1.2 Newtonian oil, nan oil that, at a given temperature,exhibits a constant viscosity at all shear rates or shear stresses.3.1.3 non-Newtonian oil, nan oil that, at a given tempera-ture, exhibits a viscosity that varies with shear stress or shearrate.3.1.4 shear rate, nvelocity gradient perpendicul
9、ar to thedirection of flow.3.1.4.1 DiscussionThe SI unit for shear rate is the recip-rocal second (1/s; also s-1).3.1.5 shear stress, nforce per unit area in the direction offlow.3.1.5.1 DiscussionThe SI unit for shear stress is thePascal (Pa).3.1.6 viscosity, nthat property of a fluid which resists
10、flow.3.1.6.1 DiscussionViscosity is defined as the ratio of theapplied shear stress (force causing flow) and the shear rate(resultant velocity of flow per unit distance from a stationarysurface wet by the fluid). Mathematically expressed:viscosity 5 shear stress/shear rate or, symbolically, h5t/G (1
11、)in which the symbols in the second portion of Eq 1 are defined by theterms in the first portion of the equation. The SI unit for viscosity usedherein is milliPascal seconds (mPas).3.2 Definitions of Terms Specific to This Test Method:31This test method is under the jurisdiction of ASTM Committee D0
12、2 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved Jan. 1, 2011. Published February 2011. Originallyapproved in 1990. Last previous edition approved in 2005 as D5133 05. DOI:10.1520/D5133-05R11.2For referenced ASTM
13、 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.3The sole source of supply of the equipment and materials known to thecommittee a
14、t this time is Tannas Co., 4800 James Savage Rd., Midland, MI 48642.If you are aware of alternative suppliers, please provide this information to ASTMInternational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.
15、1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.1 air-binding oilsthose engine oils whose borderlinepumping temperatures are determined by a combination ofgelation and viscous flow.3.2.2 borderline pumping temperature, nthat temp
16、eratureat which an engine oil may have such poor flow characteristicsthat the engine oil pump may not be capable of supplyingsufficient lubricant to the engine.3.2.3 calibration oil, nNewtonian oils developed andused to calibrate the viscometer drive module over the viscos-ity range required for thi
17、s test method.3.2.3.1 Discussionthese calibration oils are speciallyblended to give sufficient sensitivity and range for the specialviscometer head used.3.2.4 computer-programmed automated analysis, nuse ofmodern techniques for acquiring analog data, converting theseto digital values and using this
18、information to automaticallyrecord and analyze torque output from the viscometer drivemodule and to render this information into tabular data andplotted relationships.3.2.4.1 analog-to-digital (A-D) converter, na device forconverting continuously produced electrical signals into dis-crete numerical
19、values capable of being analyzed by computertechnology.3.2.5 critical pumpability temperature, nthe temperaturein the viscometer bath at which an oil reaches a chosen criticalpumpability viscosity (see 3.2.6).3.2.6 critical pumpability viscosity, nthat apparent viscos-ity believed to cause pumpabili
20、ty problems in an engine. Thisapparent viscosity is chosen to test an oil for its criticalpumpability temperature.3.2.7 flow-limited oils, nthose oils whose borderlinepumping temperatures are determined by viscous flow.3.2.8 gelation, na rheological condition of an oil charac-terized by a marked inc
21、rease in the flow resistance over andabove the normal exponential increase of viscosity withdecreasing temperature, particularly at lower shear stresses andtemperatures.3.2.8.1 DiscussionGelation has been attributed to a pro-cess of nucleation and crystallization of components of theengine oil and t
22、he formation of a structure.43.2.9 Gelation Index, nthe maximum value of the incre-mental ratio21log log h1!2log log h2!/log T12 log T2!# (2)(in which h is dynamic viscosity and T is in degrees Kelvin)over the temperature range scanned when the incrementaldecrease in temperature is 1 K.3.2.9.1 Discu
23、ssionThe technique of deriving GelationIndex was first developed and practiced5collecting informationfrom a strip-chart recording and applying the empiricalMacCoull-Walther-Wright equation (Test Method D341). Forfurther information, see Appendix X1.3.2.10 Gelation Index reference oils, nnon-Newtonia
24、noils chosen to give certain levels of Gelation Index as a checkon instrument performance3.3.2.11 Gelation Index temperature, nthe temperature (t2in Eq 2) in degrees Celsius at which the Gelation Index occurs.3.2.12 pre-treatment sample heating bath, na water or airbath to heat the samples for 1.5 t
25、o 2.0 h at 90 6 2C beforetesting.3.2.13 programmable liquid cold bath, na liquid bathhaving a temperature controller capable of being programmedto run the calibration and the analysis portions of the testmethod.3.2.14 temperature controller, na programmable devicewhich, when properly programmed, ram
26、ps the temperatureupward or downward at a chosen rate or series of steps whilesimultaneously controlling temperature excursions.3.2.14.1 calibration program, na program to run therequired series of temperatures at which the torque valuesnecessary to calibrate the viscometer drive module are col-lect
27、ed and analyzed.3.2.14.2 test program, na program to run the test oilanalysis at 1C/h temperature decrease.3.2.14.3 hold program, na program to reach and hold theprogrammable liquid cold bath at 5C.3.2.15 test cell, nthe combination of the rotor and stator.Critical elements of the test cell are sket
28、ched in Fig. 1.3.2.15.1 rotor, na titanium rotor sized to give a compro-mise of sensitivity and range to the determination of viscosityand gelation using this test method.(1) stator, na precision-bore borosilicate glass tube, towhich a measured amount of oil is added for the test and withinwhich the
29、 specially-made rotor turns.(2) stator collar, na clamp for the stator which alsopositions it on the test cell alignment device.4Symposium on Low Temperature Lubricant Rheology Measurement and Rel-evance to Engine Operation, ASTM STP 1143, Rhodes, R. B., ed., ASTM, 1992.5Selby, T.W., “The Use of the
30、 Scanning Brookfield Technique to Study theCritical Degree of Gelation of Lubricants at Low Temperatures”, SAE Paper910746, Society of Automotive Engineers, 1991.FIG. 1 Test CellD5133 05 (2011)23.2.16 test cell alignment device6, na special device usedto support the viscometer drive module while mai
31、ntaining thestator and the rotor coaxial and vertical in regard to theviscometer driveshaft. Later designs permit dry gas into thecell to prevent moisture and frost buildup.3.2.17 test oil, nany oil for which apparent viscosity is tobe determined using the procedure described by this testmethod.3.2.
32、18 viscometer drive module, nthe rotor drive andtorque-sensing component of a rotational viscometer.3.2.19 viscometer module support, na part of the test cellalignment device supporting the viscometer drive module.4. Summary of Test Method4.1 After pre-heating approximately 20 mL of the test oil ina
33、 glass stator at 90C for 1.5 to 2.0 h., the test cell containingthe test oil is attached to a suitable viscometer drive moduleand the test cell immersed in a liquid cold bath and cooled at1C/h over the temperature range of 5 to 40C. Data fromthe viscometer drive module is collected and fed to a comp
34、ut-erized data assimilation program to determine the GelationIndex, Gelation Index temperature, and Critical Pumpabilitytemperature for a selected viscosity such as 30 000 or 40 000mPas (cP).5. Significance and Use5.1 Significance of Low-Temperature, Low Shear Rate, En-gine Oil RheologyThe low-tempe
35、rature, low-shear viscomet-ric behavior of an engine oil determines whether the oil willflow to the sump inlet screen, then to the oil pump, then to thesites in the engine requiring lubrication in sufficient quantity toprevent engine damage immediately or ultimately after coldtemperature starting.5.
36、1.1 Two forms of flow problems have been identified,4flow-limited and air-binding behavior. The first form of flowrestriction, flow-limited behavior, is associated with the oilsviscosity; the second, air-binding behavior, is associated withgelation.5.2 Significance of the Test MethodThe temperature-
37、scanning technique employed by this test method was designedto determine the susceptibility of the engine oil to flow-limitedand air-binding response to slow cooling conditions by provid-ing continuous information on the rheological condition of theoil over the temperature range of use.4,5,7In this
38、way, bothviscometric and gelation response are obtained in one test.NOTE 1This test method is one of three related to pumpability relatedproblems. Measurement of low-temperature viscosity by the two otherpumpability Test Methods D3829 and D4684, hold the sample in aquiescent state and generate the a
39、pparent viscosity of the sample at shearrates ranging up to 15 sec-1and shear stresses up to 525 Pa at a previouslyselected temperature. Such difference in test parameters (shear rate, shearstress, sample motion, temperature scanning, and so forth) can lead todifferences in the measured apparent vis
40、cosity among these test methodswith some test oils, particularly when other rheological factors associatedwith gelation are present. In addition, the three methods differ consider-ably in cooling rates.5.3 Gelation Index and Gelation Index TemperatureThistest method has been further developed to yie
41、ld parameterscalled the Gelation Index and Gelation Index temperature. Thefirst parameter is a measure of the maximum rate of torqueincrease caused by the rheological response of the oil as the oilis cooled slowly. The second parameter is the temperature atwhich the Gelation Index occurs.6. Apparatu
42、s36.1 Test Cell, shown in Fig. 1, consisting of a matched rotorand a stator of the following critical dimensions:6.1.1 Rotor dimensions for: critical length is 65.5 mm (60.1mm) and critical diameter is 18.40 mm (60.02 mm).6.1.2 Stator dimensions for: critical diameter is 22.05 mm(60.02 mm) at whatev
43、er length will satisfy the immersiondepth when the upper oil level is a minimum of 15 mm belowthe cooling liquid level over the entire temperature range.6.2 Viscometer Drive Modules, rotational viscometer drivemodules capable of producing an analog signal to an analog-to-digital converter or other a
44、nalog signal data processor suchas a strip-chart recorder.6.2.1 With the rotor and stator described in 6.1.1 and 6.1.2,the viscometer drive module shall be capable of measuring toat least 45 000 mPas (cP).6.3 Test Cell Alignment Device, simultaneously maintains avertical axial alignment and reasonab
45、ly consistent positioningof the rotor in the stator to give repeatable torque readout fromtest to test when setting up the apparatus for analysis.6.3.1 Viscometer Support, supports the viscometer drivemodule and aligns it vertically.6.3.2 Stator Collar, clamps the stator and supports it whenthe stat
46、or collar is attached to the viscometer support.6.4 Ameans of providing a dry gas atmosphere over the topof the test sample is necessary to prevent condensation andfreezing of water on the oil surface.6.5 Programmable Liquid Cooling Bath, liquid bath ca-pable of running either the calibration or the
47、 testing programwith temperature control of 60.1C over the temperature rangedesired at 1C/h.6.5.1 Temperature Controller, is set up to operate accordingto two programs, the Calibration program and the test program.At any temperature the controller modulates temperaturewithin 0.1C of the desired valu
48、e.6.6 Computer, Analog-to-Digital Converter, and AnalysisProgram, means of receiving data from the viscometer drivemodule and converting this data into the desired information.6.7 Sample Pre-treatment Water or Air Bath, a program-mable water or air bath for both precise control of the test oilsat 90
49、 6 2C and immersion time after the sample reachespre-treatment temperature.6.8 Calibrated Partial-Immersion Mercury Thermometer, anASTM 34C thermometer, calibrated at 90C and reading to60.2C.6The test cell alignment device is covered by patents. Interested parties areinvited to submit information regarding the identification of alternatives to thispatented item to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee, whichyou may atte
