1、Designation: D 4921 95 (Reapproved 2006)Standard Test Method forFoaming Tendencies of Engine Coolants at RoomTemperature1This standard is issued under the fixed designation D 4921; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method applies to a simple shake test forevaluating the tendency of an aqueous solution of engine
3、coolant to foam at room temperature.1.2 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limi
4、tations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1176 Practice for Sampling and Preparing Aqueous So-lutions of Engine Coolants or Antirusts for Testing Pur-poses3. Summary of Test Method3.1 A 30 % by volume coolant concentrate solution isprepared in deionized water and shaken in a
5、stoppered gradu-ated cylinder for 30 s. The volume of foam formed in thecylinder is read in millilitres. Preparation of the sample is donein accordance with Test Method D 1176.4. Significance and Use4.1 The test method will generally identify coolants thathave a tendency to foam excessively at room
6、temperature.NOTE 1In use, the foaming tendency of a coolant solution may beincreased by service aging or contamination.5. Apparatus5.1 Graduated Cylinders100-mL graduated cylinderswith plastic stoppers are preferred for ease of handling.35.2 Water BathA water bath or equivalent device capableof main
7、taining temperature at 20 6 1C.6. Reagents6.1 Deionized Water.7. Test Conditions7.1 Test Temperature The test solution shall be main-tained at 20 6 1C for 30 min before shaking.7.2 Shake RateThe graduated cylinder containing the testsolution should be shaken vigorously for 30 s before a readingof th
8、e foam volume is taken.7.3 Number of Tests Each test solution should be tested intriplicate, using a freshly prepared test solution for each test.8. Test Procedure8.1 Prepare three 50-mL samples of a 30 % by volume(15-mL) coolant solution in deionized water. Use 100-mLgraduated cylinders.8.2 The gra
9、duated cylinders should be stoppered and placedin the constant 20 6 1C temperature water bath. Ensure thatthe test solution is submerged below the water level. Allow thetest solutions to equilibrate in the bath for 30 min.8.3 Remove the graduated cylinder from the bath and shakevigorously (using for
10、earm), making a 90 arc for approxi-mately 30 s (use a stopwatch or timing device). To avoidleakage of test contents from the cylinder, the stopper shouldbe held or locked in place.NOTE 2Secure the stopper on the graduated cylinder using thumb,index finger, or suitable locking device.8.4 Place cylind
11、er on a level surface and allow it to standundisturbed for 10 s.8.5 Record the foam volume to the nearest millilitre byreading the top level of foam and subtracting 50 mL to accountfor the liquid level.9. Report9.1 Report foam volumes (to the nearest 1.0 mL) for eachtest as well as the average of th
12、e tests.1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and is the direct responsibility of Subcommittee D15.06 on GlasswarePerformance Tests.Current edition approved April 1, 2006. Published April 2006. Originallyapproved in 1989. Last previous edition approved i
13、n 2000 as D 4921 95(2000).2For referenced ASTM 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.3Kimax or Pyrex brands have been fo
14、und to be suitable.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.10. Precision and Bias10.1 Precision:10.1.1 Repeatability of the results within a given laboratoryis normally within 15 % of the mean.10.1.2 Reproducibility among dif
15、ferent laboratories is nor-mally within 30 % of the mean.10.2 BiasSince there is no accepted reference materialsuitable for determining the bias for the procedure in this testmethod, no statement of bias is being made.11. Keywords11.1 aqueous solutions; engine coolant; foam; foam test;foaming tenden
16、ciesASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights,
17、 are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional sta
18、ndardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Com
19、mittee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 4921 95 (2006)2
