1、Designation:D492120Standard Test Method forFoaming Tendencies of Engine Coolants at RoomTemperature1This standard is issued under the fixed designation D4921;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A
2、 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 applies to a simple shake test forevaluating the tendency of an aqueous solution of enginecoolant to foam at room tempera
3、ture.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 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 app
4、ro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDev
5、elopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1176 Practice for Sampling and Preparing Aqueous Solu-tions of Engine Coolants orAntirusts for Testing Purposes3.
6、Summary of Test Method3.1 A 30%by volume coolant concentrate solution isprepared in deionized water and shaken in a 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 Practice D1176.4.Significance
7、 and Use4.1 The test method will generally identify coolants thathave a tendency to foam excessively at room temperature.NOTE1In use,the foaming tendency of a coolant solution may beincreased by service aging or contamination.5.Apparatus5.1 Graduated Cylinders100 mLgraduated cylinders withplastic st
8、oppers are preferred for ease of handling.5.2 Water BathA water bath or equivalent device capableof maintaining temperature at 22.5 C 6 2.5 C.6.Reagents6.1 Deionized Water.7.Test Conditions7.1 Test TemperatureThe test solution shall be maintainedat 22.5 C 6 2.5 C for 30 min before shaking.7.2 Shake
9、RateThe graduated cylinder containing the testsolution should be shaken vigorously for 30 s before a readingof the foam volume is taken.7.3 Number of TestsEach test solution should be tested intriplicate,using a freshly prepared test solution for each test.8.Test Procedure8.1 Prepare three 50 mL sam
10、ples of a 30%by volume(15 mL)coolant solution in deionized water.Use 100 mLgraduated cylinders.8.2 The graduated cylinders should be stoppered and placedin the constant 22.5 C 6 2.5 C temperature water bath.Ensure that the test solution is submerged below the waterlevel.Allow the test solutions to e
11、quilibrate in the bath for 30min.8.3 Remove the graduated cylinder from the bath and shakevigorously(using forearm),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.NOTE2Secure th
12、e stopper on the graduated cylinder using thumb,index finger,or suitable locking device.1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.06 on Glassware Performance Tests.Current edition approve
13、d April 1,2020.Published April 2020.Originallyapproved in 1989.Last previous edition approved in 2012 as D492195(2012).DOI:10.1520/D492120.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume inf
14、ormation,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization e
15、stablished in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.8.4 Place cylinder on a level surface and allow it to standundisturbed for 10 s.8.5 Record the foam volum
16、e 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 the tests.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 different laboratories is nor-mally within 30%of the mean.10.2 BiasSince there is no accepted reference materialsuitable for
