ASTM D1677-17 Standard Methods for Sampling and Testing Untreated Mica Paper Used for Electrical Insulation.pdf

1、Designation: D1677 17Standard Methods forSampling and Testing Untreated Mica Paper Used forElectrical Insulation1This standard is issued under the fixed designation D1677; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of

2、 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 These methods cover procedures for sampling andtesting untreated mica paper to be used as an electricalinsulator or

3、as a constituent of a composite material used forelectrical insulating purposes.1.2 The procedures2appear in the following order:ASTMMethodProcedures Sections ReferencesApparent Density 12 .Aqueous Extract Conductivity 32 and 33 D202Conditioning 4 D685Dielectric Strength 16 19 D149Impregnation Time

4、20 24 D202Moisture Content 26 28 D644Roll Quality 25 .Sampling 3 .Tensile Strength 13 15 D828Thickness 6 10 D374Weight 11 D646Weight Variability 2931 .1.3 The values stated in inch-pound units are to be regardedas the standard.1.4 This standard does not purport to address all of thesafety concerns,

5、if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with intern

6、ationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3D149 T

7、est Method for Dielectric Breakdown Voltage andDielectric Strength of Solid Electrical Insulating Materialsat Commercial Power FrequenciesD202 Test Methods for Sampling and Testing UntreatedPaper Used for Electrical InsulationD374 Test Methods for Thickness of Solid Electrical Insu-lation (Metric) D

8、0374_D0374MD644 Test Method for Moisture Content of Paper andPaperboard by Oven Drying (Withdrawn 2010)4D646 Test Method for Mass Per Unit Area of Paper andPaperboard of Aramid Papers (Basis Weight)D685 Practice for Conditioning Paper and Paper Productsfor TestingD828 Test Method for Tensile Propert

9、ies of Paper andPaperboard Using Constant-Rate-of-ElongationApparatusD1711 Terminology Relating to Electrical Insulation3. Sampling3.1 Sample in accordance with the requirements set forth inTest Methods D202.3.2 Make the tests for physical properties on each sampleinsofar as the specimens are of suf

10、ficient width.3.3 Untreated mica papers are, in general, quite fragile andfriable. At all times during the operations of sampling,conditioning, specimen preparation, and testing, great caremust be taken to prevent flexing and tearing, and to minimizeabrasion of particles from the surfaces. The test

11、values aresignificantly and adversely affected if these precautions are nottaken.1These methods are under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and are the direct responsibility ofSubcommittee D09.01 on Electrical Insulating Products.Current edition

12、approved Nov. 1, 2017. Published December 2017. Originallyapproved in 1959. Last previous edition approved in 2011 as D1677 02 (2011).DOI: 10.1520/D1677-17.2The test methods for other properties will be added in accordance with standardASTM procedures as their need becomes generally desirable.3For r

13、eferenced 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.4The last approved version of this historical standard is reference

14、d onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on sta

15、ndardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14. Conditioning4.1 Condition samples in accordance with Practice D685,except that sampl

16、es shall remain in the conditioned air for notless than 16 h prior to the tests.4.2 The following physical tests shall be made in theconditioned atmosphere: thickness, weight, tensile strength,dielectric strength, and impregnation.5. Precision and Bias5.1 Due to the range of types and grades, and no

17、nuniformnature of commercially available mica papers, no statementcan be made about the precision of these methods when usedon these materials. Neither can a statement about bias be madebecause of the unavailability of standard reference materials.Nevertheless, these methods serve to distinguish bas

18、ic, relativedifferences in properties, and variations in quality among micapapers used in electrical insulation.THICKNESS AND THICKNESS VARIATION6. Terminology Definition6.1 thickness,nof an electrical insulating material, theperpendicular distance between the two surfaces of interest,determined in

19、accordance with a standard method.7. Significance and Use7.1 Accurate determination of thickness is important foridentification purposes. Thickness is related to weight and mustbe known in order to calculate apparent density and thedielectric strength.7.2 Thickness variation affects the quality of r

20、oll windingand is useful in judging the uniformity of mica paper particu-larly with respect to dielectric breakdown voltage, impregna-tion time, and thickness of the end product.8. Test Specimens8.1 Take test specimens from the original samples obtainedin accordance with Section 3 and conditioned as

21、 prescribed inSection 4, and tested under the same conditions.8.2 For all thicknesses of mica paper, the specimen shall bea single sheet.9. Procedure9.1 Determine the thickness in accordance with Test Meth-ods D374. The preferred method shall be Method D with a droprate of 12 6 4 mil/s and a dwell t

22、ime of 3 6 1 s for thicknessof 0.002 to 0.006 in. and 6 6 2 s for + 0.006 in. Method C ofTest Methods D374 is an acceptable alternative.9.2 Take at least five measurements of thickness at regularintervals across the entire width of each specimen, preferablyin a line that is at right angles to the ma

23、chine direction.10. Report10.1 Report in accordance with Test Methods D202 andinclude:10.1.1 Average, minimum, and maximum thickness.WEIGHT11. Procedure11.1 Determine the weight in accordance with Test MethodD646, except sample the material in accordance with Section 3,condition as prescribed in Sec

24、tion 4, and test under the sameconditions. Report the results as weight in grams per squaremetre.APPARENT DENSITY12. Procedure12.1 Determine the apparent density from the thickness(Sections 810), and the weight (Section 11). Make thethickness and weight determinations on the same sample.Calculate th

25、e apparent density as follows:D 5 A/B (1)where:A = basis weight, kg/m2,B = thickness, m, andD = apparent density, g/cm3.TENSILE STRENGTH13. Significance and Use13.1 The results of the test are suitable for acceptance andproduct control. They are also a means of measuring the abilityof mica paper to

26、withstand the tensile stresses encountered inapplication processes.14. Procedure14.1 Determine the tensile strength in accordance with TestMethods D202, except for specimen width and test span.Sample the material in accordance with Section 3 and condi-tion in accordance with Section 4 and test under

27、 the sameconditions. The specimen shall be 1 to 3 in. (25 to 77 mm)wide. The distance between the jaws shall be 5 in. (127 mm).NOTE 1If excessive fractures occur in or at the edge of either jaw, usea cushion of soft kraft paper or other material between the jaws of theclamps and the specimen.15. Rep

28、ort15.1 Report the following information:15.1.1 The thickness of test specimen, and15.1.2 The average, minimum and maximum tensilestrength in pounds-force per inch of width (or newtons permetre of width).DIELECTRIC STRENGTH16. Nomenclature16.1 dielectric strengthRefer to Terminology D1711.17. Signif

29、icance and Use17.1 For mica paper to be used in the untreated state, thistest gives some indication of the electrical strength. For micapaper to be subsequently treated, this test has value as a qualitycontrol test.D1677 17218. Procedure18.1 Determine the dielectric strength in accordance withTest M

30、ethod D149, except sample the material in accordancewith Section 3 and condition in accordance with Section 4, andtest under the same conditions. Make tests in air using 2-in.(50.8-mm) electrodes and the short-time (continuous-rise)method. Determine the average dielectric strength on the basisof ten

31、 dielectric breakdowns.19. Report19.1 Report the following information:19.1.1 Average thickness of the specimen,19.1.2 Average, high, and low breakdown voltage, and19.1.3 Average dielectric strength in volts per mil (orkilovolts per millimetre).IMPREGNATION TIME20. Definition20.1 impregnation time,

32、nof paper, the time in secondsrequired for a liquid of specified composition and viscosity topenetrate completely from one face of a sheet of paper to theother, under certain prescribed conditions.21. Significance and Use21.1 Impregnation time influences the speed and quality ofresin impregnation of

33、 the mica paper.22. Test Specimens22.1 Take test specimens from the original samples obtainedin accordance with Section 3 and conditioned as prescribed inSection 4, and test under the same conditions. Test specimensshall be 3 in. (76 mm) square.23. Procedure23.1 Determine the impregnation time in ac

34、cordance withImpregnation Time of Test Methods D202, except as follows:23.1.1 Use a test solution that is approximately 60 partscastor oil and 40 parts toluene, adjusted to a specific gravity of0.917 6 0.001 at 77F (25C).NOTE 2Use cold pressed castor oil (USP Grade No. 1).23.1.2 Insert a glass plate

35、 between the mica paper and thepaper clamp.23.1.3 The end point is that time at which the paper iscompletely penetrated at a uniform rate of wet out. Particleswhich require substantially longer to wet out will not influencethe determination. Make sure that the penetrated area is 95 to100 % of the su

36、rface. This will vary with the type of micapaper. First make trial tests observing the characteristics of theend point.24. Report24.1 Report the following information:24.1.1 Thickness of the specimen, and24.1.2 Average of five readings.ROLL QUALITY25. Report25.1 Mica paper is chiefly supplied in con

37、tinuous lengths inroll form. Because roll quality determines handling propertiesof the mica paper when it is unwound on combining orimpregnating equipment, the following conditions shall beobserved and reported if they are found to occur in the roll, andto what degree:25.1.1 Sticking of layers to ea

38、ch other,25.1.2 Loose mica platelets,25.1.3 Delamination, separation, or cracking of the micapaper (that is, examine the mica paper for delamination,separation, or cracking when it is unwound and bent back onitself (reverse direction) over a 3-in. diameter mandrel andwhen it is cut across full width

39、 of the roll),25.1.4 Uneven winding tension, loosely wound ends,bagging,25.1.5 Telescoping or coning, indexing of edges,25.1.6 Position of the center of the mica paper with respectto the center of the core on which the mica paper is wound (thatis, does the center of the mica paper coincide with the

40、center ofthe core or is it offset),25.1.7 Shape of roll, for example, degrees of roundness,25.1.8 Crushed roll ends which cause tearing when thematerial is unrolled,25.1.9 Nonlinear edges in which the edge follows a longsine wave, and25.1.10 Any other unusual conditions.MOISTURE CONTENT26. Significa

41、nce and Use26.1 Excessive moisture content will cause raw mica paperto weaken significantly with lengthwise or crosswise tearing,or both, resulting when it is unwound. It has the potential toalso cause polar impregnants, or impregnants that are dissolvedin polar solvents, to impregnate to a higher d

42、egree, or at a fasterrate, or both, than is desired. It has the potential to alsocontribute to blistering of the mica paper when these impreg-nants are dried with heat. It has the potential, in addition, tocause contiguous layers of raw mica paper in the roll to stickto each other, making unwinding

43、difficult or impossible.Excessive moisture will also weaken and soften the cardboardcore upon which the mica paper is customarily rolled. Low-moisture contents are generally not as deleterious in effect,although they can conceivably cause excessive stiffness inthick mica papers.27. Procedure27.1 Det

44、ermine the moisture content in accordance withTest Method D644, except sample the material in accordancewith Section 3. Do not precondition the samples.28. Report28.1 Report the average, minimum, and maximum moisturecontent for all samples tested.D1677 173WEIGHT VARIABILITY29. Significance and Use29

45、.1 The degree of variability of basis weight (mass per unitarea) from point to point on a sheet has an effect on thephysical and electrical properties of which the sheet is acomponent.29.2 In general the variability is greater across the width ofthe sheet than along its length. For this reason, spec

46、imens forthe determination of weight variability must represent theentire width of the material being sampled.30. Procedure30.1 Sample in accordance with Section 3. The sample mustrepresent the entire width of the sheet being evaluated.30.2 Carefully cut ten specimens (see 3.3). The specimensare eit

47、her circular or rectangular, and they shall be as nearlyidentical in size as possible. The area of each specimen shall bebetween 10 and 20 in.2(0.0065 and 0.0130 mm2), and shall beknown for each specimen within 60.5 %.30.3 Space the specimens uniformly across the width of thesample. If the sample is

48、 not of sufficient width to permitspacing across, cut two or more rows of specimens.30.4 Weigh each specimen to the nearest 0.1 mg.31. Report31.1 Report the following information:31.1.1 Identification of the sample,31.1.2 Area of each specimen, or, if the range of areasbetween the smallest and large

49、st specimen differs by less than1%,31.1.3 Basis weight in grams per square metre for eachspecimen,31.1.4 Average basis weight, and31.1.5 Percentage variation of the smallest and largestindividual basis weight values from the average.AQUEOUS EXTRACT CONDUCTIVITY32. Significance and Use32.1 For mica papers that are intended for use in capacitors,the results of this test are indicative of electrical properties ofthe finished capacitor, particularly dissipation factor and insu-lation resistance.33. Procedure and Report33.1 Prepare specimens f