1、Designation:D598411Standard Test Method forSemi-Quantitative Field Test Method for Base Number inNew and Used Lubricants by Color-Indicator Titration1This standard is issued under the fixed designation D5984;the number immediately following the designation indicates the year oforiginal adoption or,i
2、n the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers a procedure for determining thebasic constituents in petroleum
3、products in the field or labora-tory using a pre-packaged test kit.The test uses a micro-titration resulting in a visual endpoint facilitated by a colorindicator.1.1.1 This test method covers base numbers from 0 to 20.Itcan be extended to higher ranges by diluting the sample or byusing a smaller sam
4、ple size;however,the precision data wereobtained for base numbers up to 20.1.2 This test method can be used to indicate relative changesthat occur in an oil during use under oxidizing conditions.Although the test is performed under closely specified condi-tions with standardized reagents,the test me
5、thod does notmeasure an absolute basic property that can be used to predictperformance of an oil under service conditions.No generalrelationship between bearing corrosion and base number isknown.1.3 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are f
6、or informationonly.1.4This 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 limitations prior to use.
7、2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD2896 Test Method for Base Number of Petroleum Productsby Potentiometric Perchloric Acid TitrationD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum and
8、Petroleum Products3.Terminology3.1 Definitions:3.1.1 base number,nthe quantity of a specified acid,expressed in terms of the equivalent number of milligrams ofpotassium hydroxide per gram of sample,required to titrate asample in a specified solvent to a specified endpoint using aspecified detection
9、system.3.1.1.1 DiscussionThis test method uses fixed amounts ofisooctane and alcoholic hydrochloric acid as the sample solventand the endpoint is defined as the amount of titrant required toreach a yellow endpoint with a methyl red indicator solution.4.Summary of Test Method4.1 To determine the base
10、 number of an oil sample,thesample is dissolved in a fixed amount of iso octane andalcoholic hydrochloric acid.The solution is mixed well with 7mL of sodium chloride solution and the aqueous and organicphases are allowed to separate.The aqueous phase is thendecanted off and a small amount of methyl
11、red indicator isadded.The solution is titrated with a solution of sodiumhydroxide contained in a calibrated 1 mL micro-burette.Whenthe solution changes from magenta to yellow,the titration isstopped and the base number is read off the side of the titrationburette.5.Significance and Use5.1 New and us
12、ed petroleum products can contain basicconstituents that are present as additives or as degradationproducts formed during service.The amount of these additivesin an oil can be determined by titrating against an acid.Thebase number is a measure of the amount of basic substance inthe oil,always under
13、the conditions of the test.A decrease inbase number is often used as a measure of lubricant degrada-tion,but any condemning limits must be empirically estab-lished.5.2 This test method uses reagents that are considered lesshazardous than most reagents used in alternate base number1This test method i
14、s under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.06 on Analysis of Lubricants.Current edition approved May 15,2011.Published July 2011.Originallyapproved in 1996.Last previous edition approved in 2007 as D598497(20
15、07).DOI:10.1520/D5984-11.2For 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.*A Summary of Changes section appears at
16、the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 methods.It uses pre-packaged reagents to facilitate basenumber determinations in the field where scientific equipmentis unavailable and quick results are at a premium.NOTE1Results obtained by this test method3are similar to thoseobtained by Test Method D2896.6.Apparatus46.1 Sampling Syringe,fixed volume of 0.35 mL.6.2 Test Tubes(2),pliable,plastic with threaded to
