1、Designation:F127702(Reapproved 2009)Standard Test Method forDetermination of Leachable Chloride in Packing andGasketing Materials by Ion-Selective Electrode Technique1This standard is issued under the fixed designation F1277;the number immediately following the designation indicates the year oforigi
2、nal adoption or,in 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.Scope1.1 This test method provides for the measurement ofchloride ion leached fr
3、om flexible graphite,asbestos,or paper-based packing and gasketing materials.Samples containing 7to 6700 g Cl-/g sample can be analyzed with this procedure.The upper concentration limit can be extended by dilution ofthe test solution.1.2 It is the responsibility of the analyst to ensure thevalidity
4、of this test method for other packing or gasketingmaterials.1.3 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresp
5、onsibility 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.A specific warningstatement is given in 8.3.2.Referenced Documents2.1 ASTM Standards:2D512 Test Methods for Chloride Ion In WaterE50 P
6、ractices for Apparatus,Reagents,and Safety Consid-erations for Chemical Analysis of Metals,Ores,andRelated MaterialsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE882 Guide for Accountability and Quality Control in theChemical Analysis Laboratory3.Su
7、mmary of Test Method3.1 Chloride ion leached from packing and gasketing mate-rials is measured potentiometrically using a chloride ion-selective electrode in conjunction with a double junction,sleeve-type reference electrode.Potentials are read using apH/mV meter having 0.1 mV readability.3.2 Acalib
8、ration curve is prepared by plotting the potentialsof known chloride solutions versus the corresponding concen-trations expressed in micrograms per millilitre.The chlorideconcentration of the test solution is determined from thecalibration curve,and this value is used to calculate the amountof chlor
9、ide in parts per million that was leached from thepacking or gasketing material.The calibration and test solu-tions must be measured at the same temperature within 61C(62F).3.3 The calibration and test solutions are diluted with ionicstrength adjustor which also minimizes possible interferencessuch
10、as ammonia,bromide,iodide,cyanide,or sulfide(see TestMethods D512).4.Significance and Use4.1 Chloride ion is highly detrimental to the valves,flanges,piping,etc.of stainless steel and copper-bearing alloys em-ployed in certain types of facilities,such as nuclear andchemical plants.Therefore,the amou
11、nt of chloride ion that canbe leached from packing and gasketing materials used in thesefacilities must be controlled closely for prevention of damage.This test method is suitable for manufacturing control and forverifying that the packing and gasketing material meets speci-fications.4.2 It is assum
12、ed that the users of this test method will beanalysts capable of performing common laboratory proceduresskillfully and safely.It is recommended that the work will beperformed in a properly equipped laboratory under appropriatequality control practices such as those described in GuideE882.5.Interfere
13、nces5.1 There is no interference from up to 500 g/mL ofsulfide,1000 g/mL of bromide or iodide,a one hundred-foldexcess of cyanide over chloride,or 1000 g/mL of ammonia.Ferric,cupric,and permanganate ions do not interfere.Mer-cury must not be present.1This test method is under the jurisdiction of AST
14、M Committee F03 on Gasketsand is the direct responsibility of Subcommittee F03.50 on Analytical Test Methods.Current edition approved Oct.1,2009.Published March 2010.Originallyapproved in 1990.Last previous edition approved in 2002 as F1277 02.DOI:10.1520/F1277-02R09.2For referenced ASTM standards,v
15、isit 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.Uni
16、ted States1 6.Apparatus6.1 Digital pH/mV Meter,with 0.1 mV readability preferred,but 1 mV readability is acceptable.6.2 Chloride Ion-Selective Electrode(Cl-),having a silverchloride(AgCl)membrane.(WarningChloride ion-selectiveelectrodes with a silver chloride/silver sulfide membrane arenot suitable as the sulfide can be oxidized by the ionic strengthadjustor used in this procedure.)6.3 Sleeve-Type Double Junction Reference Electrode.NOTE1Other types of double junction reference electrodes may be
