1、Designation: D5133 13D5133 15Standard 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 indicates the y
2、ear 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 appar
3、ent viscosity of engine oil at low temperatures.1.2 Ashear rate of approximately 0.2 s0.2 s-1 is produced at shear stresses below 100 Pa. 100 Pa.Apparent viscosity is measuredcontinuously as the sample is cooled at a rate of 1C/h1 Ch over the range 55 C to 40C,40 C, or to the temperature atwhich the
4、 viscosity exceeds 40 000 mPas 40 000 mPas (cP).1.3 The measurements resulting from this test method are viscosity, the maximum rate of viscosity increase (Gelation Index),and the temperature at which the Gelation Index occurs.1.4 Applicability to petroleum products other than engine oils has not be
5、en determined in preparing this test method.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilit
6、yof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D341 Practice for Viscosity-Temperature Charts for Liquid Petroleum ProductsD3829 Test Method for Predic
7、ting the Borderline Pumping Temperature of Engine OilD4684 Test Method for Determination of Yield Stress and Apparent Viscosity of Engine Oils at Low Temperature3. Terminology3.1 Definitions:3.1.1 apparent viscosity, nthe viscosity obtained by use of this test method.3.1.1.1 DiscussionSee 3.1.63.1.6
8、for definition of viscosity and units.3.1.2 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 temperature, exhibits a viscosity that varies with shear stress or shear rate.3.1.4 sh
9、ear rate, nvelocity gradient perpendicular to the direction of flow.3.1.4.1 Discussion1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approv
10、ed Sept. 1, 2013June 1, 2015. Published September 2013June 2015. Originally approved in 1990. Last previous edition approved in 20122013 asD5133 12.D5133 13. DOI: 10.1520/D5133-13.10.1520/D5133-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at
11、 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 user of an ASTM standard an indication of what changes have been made to the previous vers
12、ion. 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 standard as published by ASTM is to be considered the official document.*A Summary of Changes sect
13、ion appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1The SI unit for shear rate is the reciprocal second (1/s; also s-1).3.1.5 shear stress, nforce per unit area in the direction of flow.3.1.5.1 Discu
14、ssionThe SI unit for shear stress is the Pascal (Pa).3.1.6 viscosity, nthat property of a fluid which resists flow.3.1.6.1 DiscussionViscosity is defined as the ratio of the applied shear stress (force causing flow) and the shear rate (resultant velocity of flow perunit distance from a stationary su
15、rface wet by the fluid). Mathematically expressed:viscosity5shear stress/shear rate or,symbolically, 5/ (1)in which the symbols in the second portion of Eq 1 are defined by the terms in the first portion of the equation. The SIunit for viscosity used herein is milliPascal seconds (mPas).3.2 Definiti
16、ons of Terms Specific to This Standard:33.2.1 air-binding oilsthose engine oils whose borderline pumping temperatures are determined by a combination of gelationand viscous flow.3.2.2 borderline pumping temperature, nthat temperature at which an engine oil may have such poor flow characteristics tha
17、tthe engine oil pump may not be capable of supplying sufficient lubricant to the engine.3.2.3 calibration oil, nNewtonian oils developed and used to calibrate the viscometer drive module over the viscosity rangerequired for this test method.3.2.3.1 Discussionthese calibration oils are specially blen
18、ded to give sufficient sensitivity and range for the special viscometer head used.3.2.4 computer-programmed automated analysis, nuse of modern techniques for acquiring analog data, converting these todigital values and using this information to automatically record and analyze torque output from the
19、 viscometer drive module andto render this information into tabular data and plotted relationships.3.2.4.1 analog-to-digital (A-D) converter, na device for converting continuously produced electrical signals into discretenumerical values capable of being analyzed by computer technology.3.2.5 critica
20、l pumpability temperature, nthe temperature in the viscometer bath at which an oil reaches a chosen criticalpumpability viscosity (see 3.2.6).3.2.6 critical pumpability viscosity, nthat apparent viscosity believed to cause pumpability problems in an engine. Thisapparent viscosity is chosen to test a
21、n oil for its critical pumpability temperature.3.2.7 digital contact thermometer (DCT), nan electronic device consisting of a digital display and associated temperaturesensing probe.3.2.7.1 DiscussionThis device consists of a temperature sensor connected to a measuring instrument; this instrument me
22、asures the temperature-dependent quantity of the sensor, computes the temperature from the measured quantity, and provides a digital output. This digitaloutput goes to a digital display and/or recording device that may be internal or external to the device. These devices are sometimesreferred to as
23、a “digital thermometer.”3.2.7.2 DiscussionPortable electronic thermometers (PET) is an acronym sometimes used to refer to a subset of the devices covered by this definition.3.2.8 flow-limited oils, nthose oils whose borderline pumping temperatures are determined by viscous flow.3 The sole source of
24、supply of the equipment and materials known to the committee at this time is Tannas Co., 4800 James Savage Rd., Midland, MI 48642. If you areaware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeti
25、ng of theresponsible technical committee,1 which you may attend.D5133 1523.2.9 gelation, na rheological condition of an oil characterized by a marked increase in the flow resistance over and abovethe normal exponential increase of viscosity with decreasing temperature, particularly at lower shear st
26、resses and temperatures.3.2.9.1 DiscussionGelation has been attributed to a process of nucleation and crystallization of components of the engine oil and the formation ofa structure.43.2.10 Gelation Index, nthe maximum value of the incremental ratio2log log1!2log log2!#/log T12log T2! (2)(in which i
27、s dynamic viscosity and T is in degrees Kelvin) over the temperature range scanned when the incremental de-crease in temperature is 1 K.3.2.10.1 DiscussionThe technique of deriving Gelation Index was first developed and practiced5 collecting information from a strip-chart recordingand applying the e
28、mpirical MacCoull-Walther-Wright equation (Test Method D341). For further information, see Appendix X1.3.2.11 Gelation Index reference oils, nnon-Newtonian oils chosen to give certain levels of Gelation Index as a check oninstrument performance3.3.2.12 Gelation Index temperature, nthe temperature (t
29、2 in Eq 2) in degrees Celsius at which the Gelation Index occurs.3.2.13 pre-treatment sample heating bath, na water or air bath to heat the samples for 1.51.5 h to 2.0 h 2.0 h at 9090 C 62C2 C before testing.3.2.14 programmable cold bath, na liquid or dry block (referred to as direct cooling) bath h
30、aving a temperature controllercapable of being programmed to run the calibration and the analysis portions of the test method within the temperature toleranceslisted.3.2.15 temperature controller, na programmable device which, when properly programmed, ramps the temperature upwardor downward at a ch
31、osen rate or series of steps while simultaneously controlling temperature excursions.3.2.15.1 calibration program, na program to run the required series of temperatures at which the torque values necessary tocalibrate the viscometer drive module are collected and analyzed.3.2.15.2 test program, na p
32、rogram to run the test oil analysis at 1C/h1 Ch temperature decrease.3.2.15.3 hold program, na program to reach and hold the programmable liquid cold bath at 5C.5 C.3.2.16 test cell, nthe combination of the rotor and stator. Critical elements of the test cell are sketched in Fig. 1.3.2.16.1 rotor, n
33、a titanium rotor sized to give a compromise of sensitivity and range to the determination of viscosity andgelation using this test method.(1) stator, na precision-bore borosilicate glass or stainless steel tube, to which a measured amount of oil is added for the testand within which the specially-ma
34、de rotor turns.(2) stator collar, na clamp for the stator which also positions it on the test cell alignment device.3.2.17 test cell alignment device6, na special device used to support the viscometer drive module while maintaining the statorand the rotor coaxial and vertical in regard to the viscom
35、eter driveshaft. Later designs permit dry gas into the cell to preventmoisture and frost buildup.3.2.18 test oil, nany oil for which apparent viscosity is to be determined using the procedure described by this test method.3.2.19 viscometer drive module, nthe rotor drive and torque-sensing component
36、of a rotational viscometer.3.2.20 viscometer module support, na part of the test cell alignment device supporting the viscometer drive module.4. Summary of Test Method4.1 After pre-heating approximately 20 mL 20 mL of the test oil in a glass stator at 90C90 C for 1.51.5 h to 2.0 h., 2.0 h, thetest c
37、ell containing the test oil is attached to a suitable viscometer drive module and the test cell immersed in a liquid cold bathand cooled at 1C/h1 Ch over the temperature range of 55 C to 40C.40 C. Data from the viscometer drive module is4 Symposium on Low Temperature Lubricant Rheology Measurement a
38、nd Relevance to Engine Operation, ASTM STP 1143, Rhodes, R. B., ed., ASTM, 1992.5 Selby, T.W., “The Use of the Scanning Brookfield Technique to Study the Critical Degree of Gelation of Lubricants at Low Temperatures”, SAE Paper 910746, Societyof Automotive Engineers, 1991.6 The test cell alignment d
39、evice is covered by patents. Interested parties are invited to submit information regarding the identification of alternatives to this patented itemto ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may
40、attend.D5133 153collected and fed to a computerized data assimilation program to determine the Gelation Index, Gelation Index temperature, andCritical Pumpability temperature for a selected viscosity such as 30 000 or 40 000 mPas 30 000 mPas or 40 000 mPas (cP).5. Significance and Use5.1 Significanc
41、e of Low-Temperature, Low Shear Rate, Engine Oil RheologyThe low-temperature, low-shear viscometricbehavior of an engine oil determines whether the oil will flow to the sump inlet screen, then to the oil pump, then to the sites inthe engine requiring lubrication in sufficient quantity to prevent eng
42、ine damage immediately or ultimately after cold temperaturestarting.5.1.1 Two forms of flow problems have been identified,4 flow-limited and air-binding behavior. The first form of flowrestriction, flow-limited behavior, is associated with the oils viscosity; the second, air-binding behavior, is ass
43、ociated withgelation.5.2 Significance of the Test MethodThe temperature-scanning technique employed by this test method was designed todetermine the susceptibility of the engine oil to flow-limited and air-binding response to slow cooling conditions by providingcontinuous information on the rheologi
44、cal condition of the oil over the temperature range of use.4 ,5,7 In this way, both viscometricand gelation response are obtained in one test.NOTE 1This test method is one of three related to pumpability related problems. Measurement of low-temperature viscosity by the two otherpumpability Test Meth
45、ods D3829 and D4684, hold the sample in a quiescent state and generate the apparent viscosity of the sample at shear rates rangingup to 15 sec15 sec-1 and shear stresses up to 525 Pa 525 Pa at a previously selected temperature. Such difference in test parameters (shear rate, shear stress,sample moti
46、on, temperature scanning, and so forth) can lead to differences in the measured apparent viscosity among these test methods with some testoils, particularly when other rheological factors associated with gelation are present. In addition, the three methods differ considerably in cooling rates.5.3 Ge
47、lation Index and Gelation Index TemperatureThis test method has been further developed to yield parameters calledthe Gelation Index and Gelation Index temperature. The first parameter is a measure of the maximum rate of torque increase causedby the rheological response of the oil as the oil is coole
48、d slowly. The second parameter is the temperature at which the GelationIndex occurs.6. Apparatus36.1 Test Cell, shown in Fig. 1, consisting of a matched rotor and a stator of the following critical dimensions:6.1.1 Rotor dimensions for: critical length is 65.5 mm (60.1 mm) 65.5 mm (60.1 mm) and crit
49、ical diameter is 18.40 mm(60.02 mm).18.40 mm (60.02 mm).7 Shaub, H., “A History of ASTM Accomplishments in Low Temperature Engine Oil Rheology,” Symposium on Low Temperature Lubricant Rheology Measurement andRelevance to Engine Operation, ASTM STP 1143, Rhodes, R. B., ed., ASTM, 1992, pp. 1-19.Shaub, H., “A History of ASTM Accomplishments in Low Temperature EngineOil Rheology,” Symposium on Low Temperature Lubricant Rheology Measurement and Relevance to Engine Operation, ASTM STP 1
