1、Designation: D5293 14D5293 15Standard Test Method forApparent Viscosity of Engine Oils and Base StocksBetween 5 C10 C and 35 C Using Cold-CrankingSimulator1This standard is issued under the fixed designation D5293; the number immediately following the designation indicates the year oforiginal adopti
2、on 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 laboratory determination of apparent viscosit
3、y of engine oils and base stocks by cold crankingsimulator (CCS) at temperatures between 5 C10 C and 35 C at shear stresses of approximately 50 000 Pa to 100 000 Pa andshear rates of approximately 105 to 104 s1 for viscosities of approximately 900 mPas to 25 000 mPas. The range of an instrumentis de
4、pendent on the instrument model and software version installed. Apparent Cranking Viscosity results by this method arerelated to engine-cranking characteristics of engine oils.1.2 A special procedure is provided for measurement of highly viscoelastic oils in manual instruments. See Appendix X2.1.3 P
5、rocedures are provided for both manual and automated determination of the apparent viscosity of engine oils using thecold-cranking simulator.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purpor
6、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 and health practices and determine the applicability of regulatorylimitations prior to use. Specific warning statements are given in Section
7、8.2. Referenced Documents2.1 ASTM Standards:2D2162 Practice for Basic Calibration of Master Viscometers and Viscosity Oil StandardsD2602 Test Method forApparent Viscosity of Engine OilsAt Low Temperature Using the Cold-Cranking Simulator (Withdrawn1993)3D4057 Practice for Manual Sampling of Petroleu
8、m and Petroleum Products2.2 ISO Standard:ISO 17025 General Requirements for the Competence of Testing and Calibration Laboratories43. Terminology3.1 Definitions:3.1.1 Newtonian oil or fluid, none that exhibits a constant viscosity at all shear rates.3.1.2 non-Newtonian oil or fluid, none that exhibi
9、ts a viscosity that varies with changing shear stress or shear rate.3.1.3 viscosity, , nthe property of a fluid that determines its internal resistance to flow under stress, expressed by:5 (1)1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and L
10、ubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved May 1, 2014April 1, 2015. Published June 2014May 2015. Originally approved in 1991. Last previous edition approved in 20102014 asD5293 10D5293 14.1. DOI: 10.1520/D5293-14.10.1520/D5293-15.2 F
11、or referencedASTM 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.3 The last approved version of this historical standard is refer
12、enced on www.astm.org.4 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.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 th
13、e 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 standard as published by ASTM is to be considered the official document.*A Summary
14、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 States1where: = the stress per unit area, and = the rate of shear.3.1.3.1 DiscussionIt is sometimes called the coefficient of dynamic visco
15、sity. This coefficient is thus a measure of the resistance to flow of the liquid.In the SI, the unit of viscosity is the pascal-second; for practical use, a submultiple (millipascal-second) is more convenient andis customarily used. The millipascal second is 1 cP (centipoise).3.2 Definitions of Term
16、s Specific to This Standard:3.2.1 apparent viscosity, nthe viscosity obtained by use of this test method.3.2.1.1 DiscussionSince many engine oils are non-Newtonian at low temperature, apparent viscosity can vary with shear rate.3.2.2 calibration oils, noils with known viscosity and viscosity/tempera
17、ture functionality that are used to define thecalibration relationship between viscosity and cold-cranking simulator rotor speed.3.2.3 check oil, na batch of test oil used to monitor measurement performance.3.2.4 test oil, nany oil for which the apparent viscosity is to be determined by use of this
18、test method.3.2.5 viscoelastic oil, na non-Newtonian oil or fluid that climbs up the rotor shaft during rotation.4. Summary of Test Method4.1 An electric motor drives a rotor that is closely fitted inside a stator. The space between the rotor and stator is filled with oil.Test temperature is measure
19、d near the stator inner wall and maintained by removing heat with a controlled process to maintain aconstant stator temperature during test. The speed of the rotor is calibrated as a function of viscosity. Test oil viscosity isdetermined from this calibration and the measured rotor speed.5. Signific
20、ance and Use5.1 The CCS apparent viscosity of automotive engine oils correlates with low temperature engine cranking. CCS apparentviscosity is not suitable for predicting low temperature flow to the engine oil pump and oil distribution system. Engine crankingdata were measured by the Coordinating Re
21、search Council (CRC) L-495 test with reference oils that had viscosities between600 mPas and 8400 mPas (cP) at 17.8 C and between 2000 mPas and 20 000 mPas (cP) at 28.9 C. The detailed relationshipbetween this engine cranking data and CCS apparent viscosities is inAppendixes X1 and X2 of the 1967 T
22、edition of Test MethodD26026 and CRC Report 409.5 Because the CRC L-49 test is much less precise and standardized than the CCS procedures, CCSapparent viscosity need not accurately predict the engine cranking behavior of an oil in a specific engine. However, the correlationof CCS apparent viscosity
23、with average CRC L-49 engine cranking results is satisfactory.5.2 The correlation between CCS and apparent viscosity and engine cranking was confirmed at temperatures between 1 C and40 C by work on 17 commercial engine oils (SAE grades 5W, 10W, 15W, and 20W). Both synthetic and mineral oil basedprod
24、ucts were evaluated. See ASTM STP 621.75.3 Acorrelation was established in a low temperature engine performance study between light duty engine startability and CCSmeasured apparent viscosity. This study used ten 1990s engines at temperatures ranging from 5 C down to 40 C with sixcommercial engine o
25、ils (SAE 0W, 5W, 10W, 15W, 20W, and 25W).85.4 The measurement of the cranking viscosity of base stocks is typically done to determine their suitability for use in engineoil formulations. A significant number of the calibration oils for this method are base stocks that could be used in engine oilform
26、ulations.6. Apparatus6.1 Two types of apparatus are described for use in this test method: the manual cold-cranking simulator (see Appendix X1)and the automated CCS (see 6.2 and 6.3).5 CRC Report No. 409 “Evaluation of Laboratory Viscometers for Predicting Cranking Characteristics of Engine Oils at
27、-0F and -20F,” April 1968 available from theCoordinating Research Council, Inc., 219 Perimeter Center Parkway, Atlanta, GA 30346.Alpharetta, GA 30022.6 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D02-1402.7 Stewart, R. M., “
28、Engine Pumpability and Crankability Tests on Commercial “W” Grade Engine Oils Compared to Bench Test Results,” ASTM STP 621 ASTM 1967,1968. 1969 Annual Book of ASTM Standards , Part 17 (Also published as SAE Paper 780369 in SAE Publication SP-429.).8 Supporting data have been filed at ASTM Internati
29、onal Headquarters and may be obtained by requesting Research Report RR:D02-1442.D5293 1526.2 Automated CCS,9consisting of a direct current (dc) electric motor that drives a rotor inside a stator; a rotor speed sensor ortachometer that measures rotor speed; a dc ammeter and fine current-control adjus
30、t dial; a stator temperature control system thatmaintains temperature within 0.05 C of set point; and a heat removal system with a temperature control system, a computer,computer interface, and test sample injection pump.6.3 Automatic Automated CCS,9as described in 6.2 with the addition of an automa
31、ted sample table allowing multiple testsamples to be run sequentially under computer control without operator attention.6.4 Calibrated Thermistor,9sensor for insertion in a well near the inside surface of the stator to indicate the test temperature.6.4.1 There must be good thermal contact between th
32、e temperature sensor and the thermal well in the stator; clean this thermalwell periodically and replace the small drop of high-silver-containing heat transfer medium.6.5 Heat Removal System:6.5.1 For stators with coolant contact, a refrigerator for the liquid coolant is needed to maintain coolant t
33、emperature at least10 C below the test temperature. When the coolant temperature is below 30 C a two-stage refrigeration system is likely needed.The length of the tubing connections between the CCS and the refrigerator should be as short as possible (less than 1 m) and wellinsulated.6.5.1.1 Coolant,
34、 Dry MethanolIf contaminated with water from operating under high humidity conditions, replace it with drymethanol to ensure consistent temperature control.6.5.2 For thermoelectric cooled stators, the liquid cooling temperature of the water or other appropriate liquid used in therefrigeration system
35、 (chiller) should be set to approximately 5 C in order to maintain the sample test temperature. The coolantshould contain 10 % glycol to prevent blocking of the flow path by ice formation.6.6 Ultrasonic Bath, Unheated(optional)with an operating frequency between 25 kHz to 60 kHz and a typical power
36、outputof 100 W, of suitable dimensions to hold container(s) placed inside of bath, for use in effectively dissipating and removing airor gas bubbles that can be entrained in viscous sample types prior to analysis. It is permissible to use ultrasonic baths with operatingfrequencies and power outputs
37、outside this range, however it is the responsibility of the laboratory to conduct a data comparisonstudy to confirm that results determined with and without the use of such ultrasonic baths does not materially impact results.7. Reagents and Materials7.1 Calibration OilsLow-cloud point Newtonian oils
38、 shall be certified by a laboratory that has been shown to meet therequirements of ISO 17025 by independent assessment. The calibration oils shall be traceable to master viscometer proceduresdescribed in Test Method D2162. Approximate viscosities at certain temperatures are listed in Table 1, wherea
39、s exact viscositiesare supplied with each standard.8. Hazards8.1 Observe both toxicity and flammability warnings that apply to the use of methanol or glycol.8.2 If methanol is leaking from the apparatus, repair the leak before continuing the test.9. Sampling9.1 To obtain valid results, use an approp
40、riate means of bulk sampling (see Practice D4057) to obtain a representative sampleof test oil free from suspended solid material and water. When the sample in its container is received below the dew pointtemperature of the room, allow the sample to warm to room temperature before opening its contai
41、ner. When the sample containssuspended solid material, use centrifuge to remove particles greater than 5 m in size and decant off the supernate. Filtering is notrecommended. DO NOT shake the sample of test oil. This leads to entrainment of air, and a false viscosity reading.9.2 For some sample types
42、, such as viscous lube oils that are prone to having entrained air or gas bubbles present in the sample,the use of an ultrasonic bath (see 6.6) without the heater turned on (if so equipped), has been found effective in dissipating bubblestypically within 5 min.10. Calibration10.1 On start-up of a ne
43、w instrument or when any part of the viscometric cell or drive component (motor, belt, and so forth)is replaced, set the motor current as described below. Recheck the motor current (as described in 10.3) monthly until the changein motor current in consecutive months is less than 0.005 A and every th
44、ree months thereafter.10.2 Temperature VerificationUsing the temperature verification plugs, verify that the instrument is accurately computing thecorrect temperature. (Only available on newer model instruments.)10.2.1 Unplug thermistor connector from the back panel and insert blue TVP.9 The sole so
45、urce of supply of the apparatus known to the committee at this time is Cannon Instrument Co., State College, PA16804. Website: .If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consideration at a meetingo
46、f the responsible technical committee,1 which you may attend.D5293 15310.2.2 Enter the TVP resistance for the plug inserted in the software screen ServiceCCS Temperature Verification Service, andrecord the difference between the two temperature windows.10.2.3 Repeat with second plug.10.2.4 The recor
47、ded differences should be less that 0.06 C. If they are greater, contact instrument service.10.3 Motor CurrentUse the Set Motor Current option in the software with CL250 (3500 mPas) calibration oil as the sample.This option will cool then soak the sample at test temperature of 20.0 C in the same man
48、ner as for a test sample. For arecalibration proceed with 10.3.1. If rechecking motor current, proceed with 10.3.2.TABLE 1 Calibration OilsCalibration OilApproximateA Viscosity in mPas at:5 C 10 C 15 C 20 C 25 C 30 C 35 CCL080 . . . . . . 900CL090 . . . . . . 1200CL100 (10) . . . . . . 1700CL110 . .
49、 . . . 1550 2500CL120 (12) . . . . 800 1600 3200CL130 . . . . . 2900 4850CL140 (14) . . . . 1600 3250B 7000CCL150 . . . 1700 2700 4600 8050CL160 (16) . . . . 2500 5500 11 000CL170 . . 1450 2250 3700 6300 11 300CL190 (19) . . . 1800 3500B 7400C 17 000CL200 . . 1677 2650 4300 7550 13 700CL220 (22) . . 1300 2500 5100 11 000 .CL240 . . 2250 3600 6000 10 700 19 800CL250 (25) . . 1800 3500B 7400C 17 200 .CL260 . 1750 2700 4400 7500 13 400 .CL280 (28) . 1200 2500 5000 9300 . .CL
