1、Designation:D87801(Reapproved 2006)Standard Test Method forInorganic Chlorides and Sulfates in Insulating Oils1This standard is issued under the fixed designation D878;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last
2、revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been adopted for use by government agencies to replace Method 5703 of Federal Test Method Standard No.791b.This standard
3、has been approved for use by agencies of the Department of Defense.1.Scope1.1 This test method describes the qualitative determinationof inorganic chlorides and sulfates in electrical insulating oils.NOTE1It should be pointed out that if the strong acids,hydrochloricand sulfuric,are present,they wil
4、l give positive results for chlorides andsulfates,respectively.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-b
5、ility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent Water3.Summary of Test Method3.1 Water is used to extract inorganic chlorides and sulfatesfrom a test specimen of insulating oil.A portion of the waterlayer is treated with nitric a
6、cid and silver nitrate to reveal awhite precipitate if chloride is present.A second portion istreated with hydrochloric acid and barium chloride.A whiteprecipitate indicates the presence of sulfate.4.Significance and Use4.1 The presence of inorganic chlorides and sulfates in oil incontact with metal
7、 surfaces in electrical equipment can result incorrosion of transformer components.The deterioration ofmetal surfaces is dependent upon the quantity of the corrosiveagentandtheoperatingenvironment.Althoughnotquantitative,this test method is a means for recognizing thepotential for such a hazard.5.Ap
8、paratus5.1 Separatory Funnel,250-mL and 500-mL capacity.5.2 Beakers,250-mL capacity.5.3 Test Tubes,25-mL capacity.6.Reagents6.1 Purity of ReagentsUse reagent grade chemicals in alltests.Unless otherwise indicated,it is intended that all reagentsshall conform to the specifications of the Committee on
9、Analytical Reagents of the American Chemical Society,wheresuch specifications are available.3Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.6.2 Purity of Water Unless otherw
10、ise indicated,referenceto water shall be understood to mean reagent water conformingto Specification D1193,Type I or Type II.6.3 Barium Chloride Solution(100 g/L)Dissolve 100 g ofbarium chloride(BaCl22H2O)in water and dilute to 1 L.6.4 n-Heptane.6.5 HydrochloricAcid(relativedensity1.19)Concentrated
11、hydrochloric acid(HCl).6.6 Nitric Acid(relative density 1.42)Concentrated nitricacid(HNO3).6.7 Silver Nitrate Solution(100 g/L)Dissolve 100 g ofsilver nitrate(AgNO3)in water and dilute to 1 L.1This test method is under the jurisdiction of ASTM Committee D27 onElectrical Insulating Liquids and Gases
12、and is the direct responsibility of Subcom-mittee D27.06 on Chemical Test.Current edition approved Nov.1,2006.Published January 2007.Originallyapproved in 1946.Last previous edition approved in 2001 as D878 01.DOI:10.1520/D0878-01R06.2For referenced ASTM standards,visit the ASTM website,www.astm.org
13、,orcontact ASTM Customer Service at serviceastm.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
14、 reagents notlisted by the American Chemical 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,We
15、st Conshohocken,PA 19428-2959.United StatesNOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest information17.Procedure7.1 In a 250-mL separatory funnel,shake thoroughly 100mL(100 cm3)of the oil test specime
16、n with 75 mL of water at95C.Allow to separate,then draw off the water layer into a250-mL beaker.D878 01(Reapproved 2006)17.1.1 In case the separated water is not clear,filter it througha 10-cm diameter qualitative filter paper into a 250-mL beaker.The filtrate is then used for tests.As a check on the filter paper,75 mL of hot water,passed through the paper prior to filteringthe separated water,should give negative tests for chloridesand sulfates.7.1.2 In the case of high-viscosity polybutene,dil
