1、Designation:D128711Standard Test Method forpH of Engine Coolants and Antirusts1This standard is issued under the fixed designation D1287;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parenthese
2、s indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scope1.1 This test method covers the determination of the pH ofunused engine coolants a
3、nd antirusts,and used or unusedaqueous dilutions of the concentrated products.NOTE1Antirusts in solid form are not included in this test method.NOTE2It is believed that this procedure gives all the informationrequired for determining the pH of samples of engine coolant or antirustlikely to be encoun
4、tered.Should additional information on pH determi-nations be needed,reference should be made to Test Method E70.1.2 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
5、 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1176 Practice for Sampling and Preparing Aqueous Solu-tions of Engine Coolants orAntirusts for Testing PurposesE70 Test Method for pH of Aqueous Solutions With the
6、Glass Electrode3.Summary of Test Method3.1 A sample,as received or after dilution with a specifiedvolume of distilled water,is placed in a beaker or sample cupand the pH measured with a pH meter and combinationelectrode or associated glass-saturated calomel electrode pair.NOTE3The readings of the me
7、ter in the case of the concentratedproducts are not pH values according to the accepted definition,but areapparent pH values which are useful in the interpretation of the conditionof the product.4.Significance and Use4.1 pH is a measure of the hydrogen ion concentration andindicates whether an engin
8、e coolant,antirust,or a solution ofthese compounds is acidic,alkaline,or neutral.4.2 The pH range includes values from 0 to 14.Values from0 to 7 represent the acidic half of the scale.Values from 7 to 14represent the alkaline or basic half of the scale.The pH value7 is considered neutral,as it is ne
9、ither acidic nor alkaline.4.3 pH is sometimes used for production quality control.Itis generally desirable that engine coolants have an alkaline pH.4.4 pH is not significant from the standpoint of predictingservice life.The pH of used engine coolants or antirustsolutions is not a dependable indicati
10、on of either existingeffectiveness or remaining life of the solution.5.Apparatus5.1 The pH meter,glass electrode,and calomel electrode,shall be as specified in the Annex.NOTE4In pH operation,the meter may be set up to perform one-,two-or up to five-point standardizations or may be set up to automati
11、callyrecognize U.S.standard(pH 4,7 and 10)buffers,NIST/International(pH1.68,4.01,6.86,9.18 and 12.46)buffers,or a custom user-centered set ofbuffers,or both.6.Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents sh
12、all conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused,provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy
13、 of the determination.6.2 Purity of WaterUnless otherwise indicated,referencesto water shall be understood to mean distilled water or water of1This test method is under the jurisdiction of ASTM Committee D15 on EngineCoolants and Related Fluids and is the direct responsibility of SubcommitteeD15.04
14、on Chemical Properties.Current edition approved Oct.1,2011.Published October 2011.Originallyapproved in 1953 as D1287 53 T.Last previous edition approved in 2009 asD1287 09.DOI:10.1520/D1287-11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serv
15、iceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Reagent Chemicals,American Chemical Society Specifications,AmericanChemical Society,Washington,DC.For suggestions on the testing of reagents notlisted by the American Chem
16、ical Society,see Analar Standards for LaboratoryChemicals,BDH Ltd.,Poole,Dorset,U.K.,and the United States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 equal purity.Distilled water shall be boiled thoroughly,orpurged with carbon dioxide-free air,to remove carbon dioxideand shall be protected with a soda-lime tube or its equivalentwhile cooling a