ASTM D176-2007 Standard Test Methods for Solid Filling and Treating Compounds Used for Electrical Insulation《电气绝缘用固体充填和处理混合物的标准试验方法》.pdf

1、Designation: D 176 07An American National StandardStandard Test Methods forSolid Filling and Treating Compounds Used for ElectricalInsulation1This standard is issued under the fixed designation D 176; the number immediately following the designation indicates the year oforiginal adoption or, in the

2、case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover physical and electrical testsfor solid filling and treating c

3、ompounds used for electricalinsulation which are fusible to a liquid without significantchemical reaction. Compounds that are converted to the solidstate by polymerization, condensation, or other chemical reac-tion are not included in these test methods.1.2 These test methods are designed primarily

4、for asphalticor bituminous compounds, waxes, and fusible resins, or mix-tures thereof, although some of these methods are applicable tosemisolid types such as petrolatums. Special methods moresuitable for hydrocarbon waxes are contained in Test MethodsD 1168.1.3 Provide adequate ventilation when the

5、se tests involveheating.1.4 The test methods appear in the following sections:Test Method SectionsElectrical Tests:A-C Loss Characteristics and Permittivity (Dielectric Constant) 51-54Dielectric Strength 42-45Volume Resistivity-Temperature Characteristics 46-49Physical Tests:Coefficient of Expansion

6、 or Contraction 22-41Flash and Fire Points 9 and 10Loss on Heating 11 and 12Melting Point 5 and 6Penetration 15 and 16Softening Point 7 and 8Specific Gravity 17-21Viscosity 13 and 141.5 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informati

7、ononly.1.6 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For spe

8、cific hazardstatements, see 12.1 and 31.5.NOTE 1There is no similar or equivalent IEC or ISO standard.2. Referenced Documents2.1 ASTM Standards:2D5 Test Method for Penetration of Bituminous MaterialsD6 Test Method for Loss on Heating of Oil and AsphalticCompoundsD70 Test Method for Density of Semi-S

9、olid BituminousMaterials (Pycnometer Method)D71 Test Method for Relative Density of Solid Pitch andAsphalt (Displacement Method)D88 Test Method for Saybolt ViscosityD92 Test Method for Flash and Fire Points by ClevelandOpen Cup TesterD 127 Test Method for Drop Melting Point of PetroleumWax, Includin

10、g PetrolatumD 149 Test Method for Dielectric Breakdown Voltage andDielectric Strength of Solid Electrical Insulating Materialsat Commercial Power FrequenciesD 150 Test Methods for AC Loss Characteristics and Per-mittivity (Dielectric Constant) of Solid Electrical Insula-tionD 257 Test Methods for DC

11、 Resistance or Conductance ofInsulating MaterialsD 937 Test Method for Cone Penetration of PetrolatumD 1168 Test Methods for Hydrocarbon Waxes Used forElectrical InsulationD 1711 Terminology Relating to Electrical InsulationE28 Test Methods for Softening Point of Resins Derivedfrom Naval Stores by R

12、ing-and-Ball ApparatusE 102 Test Method for Saybolt Furol Viscosity of Bitumi-nous Materials at High Temperatures3. Terminology3.1 Definitions:3.1.1 dielectric strength, nthe voltage gradient at whichdielectric failure of the insulating material occurs under spe-cific conditions of test.1These metho

13、ds of testing are under the jurisdiction of ASTM Committee D09on Electrical and Electronic Insulating Materials and are the direct responsibility ofSubcommittee D09.01 on Electrical Insulating Varnishes, Powders and Encapsulat-ing Compounds.Current edition approved May 1, 2007. Published June 2007.

14、Originallyapproved in 1923. Last previous edition approved in 2000 as D 176 00.2For 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 o

15、nthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.2 For definitions of other terms relating to electricalinsulation see Terminology D 1711.3.2 Defi

16、nitions of Terms Specific to This Standard:3.2.1 loss on heating, nof filling or treating compound,the change in weight of a compound when heated underprescribed conditions at a standard temperature for a specifiedtime.3.2.2 melting point, nof filling or treating compound, thetemperature at which th

17、e compound becomes sufficiently fluidto drop from the thermometer used in making the determina-tion under prescribed conditions.3.2.3 penetration, nof filling or treating compound, thedistance traveled by a standard needle (or cone) as it pierces aspecimen under specified conditions of load, time an

18、d tempera-ture.3.2.4 softening point, nof filling or treating compound,the temperature at which the central portion of a disk of thecompound held within a horizontal ring of specified dimen-sions has sagged or flowed downward a distance of 25 mm (1in.) under the weight of a 10-mm (38-in.) diameter s

19、teel ball asthe sample is heated at a prescribed rate in a water or glycerinbath.4. Sampling and Conditioning4.1 Due to the diverse nature of the compounds and thevarious forms and packages commercially available, no stan-dard methods of sampling have been established. When thesample is in the form

20、of cakes or ingots, a representativesample is usually secured by breaking or cutting a transversesection from the middle of the cake or ingot. When the materialis shipped in pails or drums, a sample is removed with a cleanknife, hatchet, auger or other cutting tool, discarding the top 50or 75 mm (2

21、or 3 in.) of the compound. Melting of thecompound should be avoided unless it can be poured directlyinto the testing container.Amelting and pouring temperature of50 C (90 F) above the softening point is recommended forfilling testing containers with asphaltic compounds. Take carenot to overheat the

22、compound nor to entrap air.4.2 With certain materials that tend to entrap gasses due tohigh viscosity at pouring temperatures, or to froth on heating,it is necessary to degas the material prior to testing in order thatconsistent results are secured (unless the particular test in-cludes such procedur

23、e). If degassing is required, perform byheating the material in a vacuum oven. Ensure the temperatureand vacuum are high enough, and the time long enough todrive off the mechanically entrapped gasses, but not so high todecompose the material. A temperature 50 C (90 F) higherthan the softening point

24、of the compound, an absolute pressureof 7 to 21 kPa (1 to 3 psi), and a time of 30 to 45 min arerecommended for asphaltic compounds. Pour the sample intothe testing container.PHYSICAL TESTSMELTING POINT5. Significance and Use5.1 The melting point is useful in selecting a filling ortreating compound

25、that will not flow at the operating tempera-ture of the device in which it will be used. It is also essentialthat it shall not be so high as to injure the insulation at the timeof pouring. This test method is suitable for specification,classification, and for control of product uniformity.6. Procedu

26、re6.1 Determine the melting point of petrolatums, waxes, andsimilar compounds of a relatively sharp melting point by TestMethod D 127.NOTE 2This method should not be used for asphalts and other typeswith a prolonged melting range.SOFTENING POINT7. Significance and Use7.1 The softening point is usefu

27、l in selecting a filling ortreating compound that will not flow at the operating tempera-ture of the device in which it is used. It is also an indication ofthe pouring temperature, which should not be so high as toinjure the insulation of a device. This test method is used, whenthe compound has no d

28、efinite melting point, for purposes ofspecification, classification, and control of product uniformity.8. Procedure8.1 Determine the softening point in accordance with TestMethod E28.FLASH AND FIRE POINTS9. Significance and Use9.1 The flash and fire points must be high enough so that thepossibility

29、of an explosion or fire is at a minimum when thecompounds are being heated and poured. A flash point at least35 C (63 F) above the pouring temperature is usuallyconsidered necessary for safe operations. An unusually lowflash point for a given compound indicates a mixture orcontamination with a volat

30、ile material. This test method isuseful for purposes of specification, classification, and controlof product uniformity.10. Procedure10.1 Determine the flash and fire points of all compounds inaccordance with Test Method D92.10.2 In the case of certain compounds containing chlorine,the flash has the

31、 potential to be indefinite and no fire pointexists. Report this fact.LOSS ON HEATING11. Significance and Use11.1 Loss on heating includes loss of moisture and volatileconstituents less any weight gain due to oxidization. It is usefulD176072for control of product uniformity and as an indication of p

32、ot ortank life if the test is performed at the appropriate temperature.This test method shall not be used to compare compounds ofdifferent basic chemical compositions.12. Procedure12.1 Determine the loss on heating of asphaltic and certainother types of compounds by Test Method D6.NOTE 3The reproduc

33、ibility of this test method has the potential to bepoor due to insufficient control of the air circulation over the specimensand to weight gain from oxidation of some compounds. With certaincompounds it is desirable to conduct the test at a lower temperature thanthe specified temperature of 163 C (3

34、25 F).WarningWhen compounds of low flash point and highvolatility are tested, the oven shall have low-temperatureheating elements and a safety door latch to relieve pressure incase of an explosion.VISCOSITY13. Significance and Use13.1 The Saybolt viscosity is nearly proportional to thekinematic visc

35、osity of filling and treating compounds andhence, it is an indication of whether or not the material willflow readily under its own weight at a prescribed temperature.It is also satisfactory for control of product uniformity and forspecification purposes.14. Procedure14.1 For waxes, petrolatums, and

36、 other low-viscosity-typecompounds determine the viscosity as Saybolt Universal vis-cosity by Test Method D88. The standard temperatures fortesting are: 21, 38, 54, or 99 C (70, 100, 130, or 210 F).14.2 For asphaltic and other high-viscosity compounds,determine the Saybolt Furol viscosity. The stand

37、ard tempera-tures for testing Furol viscosity are: 25, 38, 50, 60, 82, and 99C (77, 100, 122, 140, 180, 210 F).14.3 For higher temperatures, special techniques and ther-mometers are required. The standard temperatures are 121,149, 177, 204, and 232 C (250, 300, 350, 400, 450 F). Inthese cases determ

38、ine the viscosity by Test Method E 102.NOTE 4For testing waxes and petrolatums, the standard temperaturefor comparison purposes is 99 C (210 F), and Saybolt Universalviscosity is used. For estimation of the properties of asphaltic and othercompounds of high viscosity, it is desirable to measure the

39、viscosity at anumber of standard temperatures above the softening point. A curve isplotted on log-log paper and the temperature at which the Saybolt Furolviscosity is 470 s is determined. This viscosity corresponds approximatelyto a kinematic viscosity of 1000 centistokes, and is a viscosity at whic

40、h thecompound is conveniently poured from the container. With pottingcompounds, it is also desirable to know the temperature at which theSaybolt Furol viscosity is 100 s, since this viscosity is low enough forproduction potting operations.PENETRATION15. Significance and Use15.1 Penetration is an ind

41、ication of the softness or indent-ability of a compound. Penetration values are used as a basisfor classification, specification, and control of product unifor-mity.16. Procedure16.1 Determine penetration in accordance with Test MethodD5. This test method is applicable to all compounds exceptvery so

42、ft materials and petrolatums. Unless specified other-wise, the standard conditions of test are:Weight, g Time, sAt 25 C (77 F) 100 5Other standard conditions are:Weight, g Time, sAt0C(32F)At 46 C (115 F)2005060516.2 For very soft materials, such as petrolatums, use TestMethod D 937.SPECIFIC GRAVITY1

43、7. Significance and Use17.1 Specific gravity is useful for indicating product unifor-mity and for calculating the weight of a given volume ofmaterial. In some instances it is useful in estimating the amountof mineral fillers in a compound. If specific gravity is known atseveral temperatures, the coe

44、fficient of expansion is calculated.If the specific gravity of a compound is determined before andafter degassing, it is possible to calculate the volume ofentrapped gasses.17.2 Displacement tests are used to determine the specificgravity of both untreated and degassed compounds. Conven-tional metho

45、ds are used for the solid state, and plummetdisplacement for the liquid state. The values obtained have thepotential to be used to compute the approximate coefficient ofcubical expansion by Test Method C (see Sections 34-36).WATER DISPLACEMENT METHODS18. Procedure18.1 Determine the specific gravity

46、by Test Method D70orTest Method D71.PLUMMET DISPLACEMENT METHOD19. Scope19.1 The specific gravity of the material at the desiredtemperature is calculated from the weight of the compounddisplaced by a calibrated aluminum plummet.20. Apparatus20.1 BalanceAn analytical balance equipped with panstraddle

47、.20.2 PlummetAn aluminum plummet of suitable shapeweighing 5 to 10 g.20.3 BeakerA 400-mL heat-resistant glass beakerwrapped with a suitable thermal insulation.20.4 ThermometerA thermometer of suitable range.20.5 WireTwo pieces of fine copper wire.21. Procedure21.1 Calibration of PlummetMake the foll

48、owing weightdeterminations of the plummet to the nearest 1 mg as follows:D176073a 2 b 5 weight of water displacement in grams at 25 C 77 F!(1)where:a = weight in air, g, andb = weight suspended in water, g, at 25 C (77 F).21.2 Correct the value of the plummet displacement (Dtp)interms of grams of wa

49、ter at 25 C (77 F) to the pouringtemperature, tp, in degrees Celsius, by means of the followingequationDtp5 0.000076tp2 25!a 2 b! 1 a 2 b! (2)NOTE 5The factor 0.000076 is the coefficient of cubical expansionper degree Celsius.21.3 Testing of the SampleCarefully melt the sample inthe beaker and raise the temperature to approximately 15 C(27 F) above the desired test temperature. Place the beaker onthe straddle and suspend the plummet in the compound by thefine copper wire. (The weight of the wire should be tared.)21.4 Balance the sc