1、Designation:D275894(Reapproved 2009)Standard Test Method forEngine Coolants by Engine Dynamometer1This standard is issued under the fixed designation D2758;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A n
2、umber 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 a full-scale clean engine testdesigned to evaluate corrosion protection and inhibitor stabilityof engine coolants un
3、der simulated heavy-duty driving condi-tions.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of t
4、he user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.Specific hazardsstatements are given in Section 6.2.Referenced Documents2.1 ASTM Standards:2D1121 Test Method for Reserve Alkalinity of Engine Cool-a
5、nts and AntirustsD1287 Test Method for pH of Engine Coolants andAntirustsD1384 Test Method for Corrosion Test for Engine Coolantsin GlasswareG1 Practice for Preparing,Cleaning,and Evaluating Corro-sion Test Specimens2.2 Federal Standard:3CFR Title 29 OSHA Regulations3.Summary of Test Method3.1 This
6、test method involves the operation of a standardpassenger car engine on a dynamometer stand under constantspeed,load,and coolant temperature conditions for a total of700 h.The performance of the coolant is judged by examina-tion of(1)coolant samples,(2)metal corrosion specimens,and(3)cooling system
7、components.4.Significance and Use4.1 This test method provides a laboratory technique ca-pable of reproducing the complex environmental stresses acoolant encounters under actual engine operating conditions.The test method provides improved discrimination over glass-ware and simulated service tests a
8、nd improved correlation withfield service.Although the test method is particularly valuablefor developing coolants for increased service requirements,itremains that field testing is necessary to evaluate coolantperformance completely.5.Apparatus5.1 Test Engine The test engine shall be a volume pro-d
9、uction passenger car engine of cast iron or aluminum con-struction.Engine speed and brake horsepower should becalculated and adjusted to be equivalent to a 96.5 km/h(60mph)level road load.Aluminum accessories,such as coolantpump and timing chain cover,are optional.The engine shall beequipped with a
10、matching radiator and pressure cap.A coolantoverflow reservoir and closed-system pressure cap areoptional,except when specified by the manufacturer.Assemblethe test components to provide a complete cooling system.Therelative positioning of the radiator and engine should duplicate,as closely as pract
11、icable,the mounting in the automobile withthe fan omitted.All radiator hose lengths should be held to aminimum.The radiator shall be cooled by forced air.5.2 Instrumentation and Control(See Fig.1)Run theengine on a test stand coupled to an engine dynamometer withappropriate accessories for control o
12、f the designated operatingconditions.Measure engine coolant temperature out of theengine at a point immediately adjacent to the coolant outlet.Measure manifold vacuum,oil pressure,and exhaust pressureat appropriate points and monitor them throughout the test inorder to ensure proper engine performan
13、ce.Install a pressuregage in the outlet tank of a crossflow radiator or the top tank ofa downflow radiator to read the gage pressure.5.3 Corrosion Measurements:5.3.1 Evaluate corrosion protection using metal specimens.The specimen arrangement shall be basically that used in TestMethod D1384.The spec
14、imen bundle is shown in Fig.2.1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.10 on Dynamometer and Road Tests.Current edition approved Nov.1,2009.Published December 2009.Originallyapproved in
15、1968 as D2758 68 T.Last previous edition D2758 94(2003).DOI:10.1520/D2758-94R09.2For 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
16、 ASTM website.3Available from the Occupational Safety and Health Administration,200Constitution Ave.,N.W.,Washington,DC 20008.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Preparation,cleaning,and weighing of the metal specimens aredescribed in Test Method D1384 and Practice G1.Eachspecimen bundle shall be held in a canvas-reinforced phenolictube(see Fig.3)which,in turn,is contained in a capsule.Usetwo types of specimen capsules:ful