1、Designation:D455999(Reapproved 2010)Standard Test Method forVolatile Matter in Silicone Fluid1This standard is issued under the fixed designation D4559;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A numbe
2、r 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 describes a procedure for determiningthe volatile matter in silicone fluids used for electrical insula-tion.1.2 The values stat
3、ed in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of whoever uses this standard to consult andestablish appropriate saf
4、ety and health practices and deter-mine the applicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D923 Practices for Sampling Electrical Insulating LiquidsD5423 Specification for Forced-Convection Laboratory Ov-ens for Evaluation of Electrical Insulation3.Sum
5、mary of Test Method3.1 Specimens are weighed before and after heating for aspecific time in a forced air oven to determine weight loss.4.Significance and Use4.1 High values may indicate contamination of the siliconewith other materials,inadequate removal of volatile compo-nents by the producer,or th
6、e presence of a depolymerizationcatalyst.4.2 The outcome will be affected directly by the presence ofany high vapor pressure material in the sample,such assolvents or low molecular weight silicones.4.3 A high volatile content could also indicate the presenceof a depolymerization catalyst in the flui
7、d.The time andtemperature specified in this test method are ideal for detectingthe effect of such a material,as the depolymerization takesplace at a highly accelerated rate and the low molecular weightcomponents are rapidly evaporated.The result is a verysignificant weight loss during the test perio
8、d.The exact amountdepends on the type and amount of catalyst present.Theconditions specified in the method should not cause measure-able depolymerization of silicone if such a catalyst is notpresent.5.Apparatus5.1 Air-circulating Oven,capable of meeting the require-ments of Specification D5423.5.2 G
9、riffn Pyrex Beakers,50-mL,with the following di-mensions:5.2.1 Outside Diameter42 6 0.6 mm.5.2.2 Wall Thickness0.14 to 0.165 mm.5.3 Analytical Balance,capable of measuring to 1 mg.6.Sampling6.1 Obtain a sample of the silicone fluid to be tested usingappropriateASTM sampling apparatus in accordance w
10、ith TestMethods D923.7.Procedure7.1 Clean two 50-mL beakers by washing in toluene,followed by a rinse in acetone or other appropriate cleaningmethod.7.2 Bake two 50-mL beakers at 150 6 5C for a minimumof 1 h,transfer to a desiccator using clean,dry gloves orcrucible tongs and cool the beakers to amb
11、ient temperatures.Use clean,dry gloves or crucible tongs to handle beakers fromthis point forward.Weigh each beaker to the nearest mg(T).7.3 Weigh a 2.0 6 0.2 g sample to the nearest mg in eachbeaker(W1).7.4 Heat at 150 6 5C in an air circulating oven for 24 60.25 h,cool in a desiccator,and reweigh(
12、W2).8.Calculation and Report8.1 Calculate the volatile matter in silicone fluid as follows:Volatile Matter,%5W12 W2W12 T31001This test method is under the jurisdiction of ASTM Committee D27 onElectrical Insulating Liquids and Gasesand is the direct responsibility of Subcom-mittee D27.07 on Physical
13、Test.Current edition approved May 1,2010.Published May 2010.Originallyapproved in 1986.Last previous edition approved in 2004 as D4559 99(2004).DOI:10.1520/D4559-99R10.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Boo
14、k 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.United States1 where:W1=weight of silicone fluid and beaker,W2=weight of silicone fluid and beaker afte
15、r heating,andT=weight of beaker.8.2 Calculate the volatile matter,as the simple averagepercentage of the two tests.8.3 Report the simple average of the two tests,rounded tothe nearest 0.1%as the volatile matter,%.9.Precision and Bias39.1 RepeatabilityThe difference between results obtainedby the sam
16、e operator with the same apparatus under constantoperating conditions on identical test material would,in thelong run,exceed the value of 0.243 only one case in twenty.9.2 ReproducibilityThe difference between two single andindependent results obtained by different operators working indifferent laboratories on identical test material would,in thelong run,exceed the value of 0.565 only one case in twenty.9.3 BiasAn estimate of bias of-0.032 was obtained forthis test method using the spiked values