1、Designation: D2129 05 (Reapproved 2010)Standard Test Method forColor of Clear ElectricalInsulating Liquids (Platinum-Cobalt Scale)1This standard is issued under the fixed designation D2129; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, 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 standard describes a test method for the visualdetermination of the color of clear insulating
3、liquids.1.2 The values stated 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 the user of this standard to establ
4、ish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)D1500 Test Method forASTM Color of
5、Petroleum Products(ASTM Color Scale)3. Summary of Test Method3.1 The color determined by this test method is derived bycomparing the color of the test specimen with that of a seriesof numbered color reference standards using transmitted lightunder prescribed conditions. The procedure described is ba
6、sedon that for measuring the color of water and clear liquidsaccording to the platinum-cobalt scale. This scale is suitablefor measurements over the color range from 5 to 300. The colorof test specimens darker than 300 on the platinum-cobalt scalemust be measured according to the ASTM Color Scale as
7、described in Test Method D1500. The use of the platinum-cobalt scale in this way is primarily of value as an expansionof the lower part of the ASTM Color Scale, especially in therange between 0 and 1.4. Significance and Use4.1 Color is significant chiefly as an indicator of contami-nation in electri
8、cal insulating liquids. Frequently this contami-nation is the result of solvent action in the apparatus involvedor it may indicate possible contamination. No definite relation-ship can be established between color and the physical andelectrical characteristics of the liquid; for that reason color in
9、itself has limited value as a measure of condition. For moreprecise determination of color, Test Method D1209 may beused.5. Apparatus5.1 Color Comparison TubesMatched, tall-form Nesslertubes, graduated at the 50-mL mark, and provided withground-on, optically clear glass caps.5.2 Color ComparatorA co
10、lor comparator constructed topermit visual comparison of light transmitted through tall-formNessler tubes in the direction of their longitudinal axes. Thecomparator should be constructed so that white light is passedthrough or reflected off a white glass plate and directed withequal intensity throug
11、h the tubes, and should be shielded sothat no light enters the tubes from the side.36. Reagents6.1 Purity of ReagentsUse reagent grade chemicals in alltests. Unless otherwise indicated, all reagents will conform tothe specifications of the Committee on Analytical Reagents ofthe American Chemical Soc
12、iety, where such specifications areavailable.4Other grades may be used, provided it is firstascertained that the reagent is of sufficiently high purity topermit its use without lessening the accuracy of the determi-nation.6.2 Purity of WaterUse reagent water conforming toSpecification D1193.6.3 Solv
13、ent, suitable, clear.6.4 Cobaltous Chloride (CoCl26H2O).1This test method is under the jurisdiction of ASTM Committee on D27 onElectrical Insulating Liquids and Gases and is the direct responsibility of Subcom-mittee D27.07 on Physical Test.Current edition approved Nov. 1, 2010. Published November 2
14、010. Originallyapproved in 1962 as D2129 - 62 T. Last previous edition approved in 2005 asD2129 - 05. DOI: 10.1520/D2129-05R10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information
15、, refer to the standards Document Summary page onthe ASTM website.3A unit available from Scientific Glass and Instruments, Inc. P.O. Box 6,Houston, TX 77001, has been found suitable for this purpose.4“Reagent Chemicals, American Chemical Society Specifications,” Am. Chemi-cal Soc., Washington, DC. F
16、or suggestions on the testing of reagents not listed bytheAmerican Chemical Society, see “Reagent Chemicals and Standards,” by JosephRosin, D. Van Nostrand Co., Inc., New York, NY and the “United StatesPharmacopeia.”1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken
17、, PA 19428-2959, United States.6.5 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).6.6 Potassium Chloroplatinate (K2PtCl6).7. Preparation of Color Standards7.1 Platinum-Cobalt Stock SolutionDissolve 1.245 g ofK2PtCl6(containing 0.5 g of platinum) and 1.000 g ofCoCl26H2O (containi
18、ng about 0.25 g of cobalt) in water. Add100 mL of HCl (sp gr 1.19) and dilute to 1 L with water. Thissolution has a color of 500.NOTE 1The color standard stock solution (platinum-cobalt solution)can be purchased with a color of 500 from laboratory supply firms.7.2 Platinum-Cobalt Standards5The unit
19、of color is thatcolor produced by 1 mg of platinum per litre. From the stocksolution, prepare color standards, as given in Table 1,bydiluting the required volumes to 50 mL with water in theNessler tubes. Cap the tubes and seal the caps with shellac ora waterproof cement.8. Procedure8.1 Introduce 50
20、mL of the test specimen into a Nesslertube, passing the sample through a filter if it has any visible testspecimen turbidity. Cap the tube, place in the comparator, andcompare with the standards.8.2 If the recorded color of the test specimen is greater than300, do not use the platinum-cobalt scale.
21、Use Test MethodD1500 to measure color.9. Report9.1 Report which method was used, Test Method D2129 orTest Method D1500.9.2 Report as the color, the number of the standard that mostnearly matches the test specimen. In the event that the colorlies midway between two standards, report the darker of the
22、two.9.3 If, owing to differences in hue between the test specimenand the standards, a definite match cannot be obtained, reportthe range over which an apparent match is obtained, and reportthe test specimen as “off-hue.”10. Precision and Bias10.1 An estimate of the repeatability has been developedba
23、sed on data supplied by a single laboratory. These data arepresented in Appendix X1. These results suggest that anestimate of the 95 % repeatability limit for color by TestMethod D2129 is 15.1 % of the test result or approximately 4.5when the mean color level is 30.10.2 It is not possible to specify
24、 the reproducibility of theprocedure in Test Method D2129 for measuring color of cleardielectric liquids because there is an insufficient number oflaboratories available to participate in an interlaboratory roundrobin program required to produce the necessary data.10.3 No information can be presente
25、d on the bias of theprocedure in Test Method D2129 for measuring the color ofclear dielectric liquids because no material having an acceptedreference value is available.11. Keywords11.1 clear liquids; color; insulating liquids; platinum-cobaltcolor scaleAPPENDIXX1. REPEATABILITY DATA ESTIMATE FOR A
26、SINGLE OPERATOR TEST SERIES OF ANALYSESX1.1 Data are given from a single laboratory, singleoperator analysis for the visual determination of the color ofclear electrical insulating liquids. The test results are from asingle set of test results on a single sample and are presented inTable X1.1. The s
27、tandard deviations and repeatability arecalculated from a sample with a nominal color number of 30and represent variations from that particular color number.5The preparation of these platinum-cobalt standards was originally described byHazen, A., American Chemical Journal, ACJOA, Vol 14, 1982, p. 30
28、0. Thedescription given in this Test Method D2129 is identical with that given in theStandard Methods for the Examination of Water and Sewage, American PublicHealth Assn., Ninth Edition, p. 14. A description is also given by Scott, W. W.,Standard Method of Chemical Analysis, D. Van Nostrand Co., Inc
29、., Fifth Edition,Vol 2, p. 2048.TABLE 1 Platinum-Cobalt Color Standards (for 50-mL Tubes)ColorStandardNumberStockSolution,mLColorStandardNumberStockSolution,mLColorStandardNumberStockSolution,mL5 0.5 35 3.5 150 15.010 1.0 40 4.0 200 20.015 1.5 50 5.0 250 25.020 2.0 60 6.0 300 30.025 2.5 70 7.0 350 3
30、5.030 3.0 100 10.0 400 40.0450 45.0D2129 05 (2010)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent righ
31、ts, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for
32、revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing
33、you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may
34、be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE X1.1 Results of Separate Color DeterminationSample Report13023325435363073839310 30Average 29.5Sr1.58CV, % 5.4r, % 15.1D2129 05 (2010)3
