1、Designation: D 3288/D 3288M 08An American National StandardStandard Test Methods forMagnet-Wire Enamels1This standard is issued under the fixed designation D 3288/D 3288M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover testing liquid enamel coatingsused to produce film-insulated magnet wire.1.2 The values st
3、ated in either lbs/gal or SI units are to beregarded separately as standard.1.3 The test methods appear as follows:SectionsDensity 6-10Determined Solids 16-22Effective Solids 31-37Flash Point 11-15Infrared Analysis 42-47Stack Loss 23-30Viscosity 38-411.4 There is no known IEC equivalent document.1.5
4、 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.2. Referenced Docu
5、ments2.1 ASTM Standards:2D29 Test Methods for Sampling and Testing Lac Resins3D56 Test Method for Flash Point by Tag Closed Cup TesterD 476 Classification for Dry Pigmentary Titanium DioxideProductsD 1298 Test Method for Density, Relative Density (SpecificGravity), or API Gravity of Crude Petroleum
6、and LiquidPetroleum Products by Hydrometer MethodD 1475 Test Method For Density of Liquid Coatings, Inks,and Related ProductsD 1638 Methods of Testing Urethane Foam Isocyanate RawMaterials3D 1711 Terminology Relating to Electrical InsulationD 5423 Specification for Forced-Convection LaboratoryOvens
7、for Evaluation of Electrical InsulationE 131 Terminology Relating to Molecular SpectroscopyE 168 Practices for General Techniques of Infrared Quanti-tative AnalysisE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions:3.1.1 For
8、 definitions of terms used in these test methods,refer to Terminology D 1711.3.2 Definitions of terms specific to this standard:3.2.1 For definitions of terms specific to this standard, seethe individual test methods.4. Significance and Use4.1 These tests are useful for specification and controlpurp
9、oses during the manufacture, purchase, and use of themagnet-wire enamels, and for determining uniformity ofbatches.5. Sampling5.1 Take a representative sample of liquid enamel and storefor future testing. Store the sample at room temperature in atightly sealed, nearly full container, unless otherwis
10、e specified.Use a container that is inert and impermeable to the wireenamel. These precautions avoid either the escape of solvent orreaction with the container and atmosphere. Glass and somemetals are suitable materials. Copper, iron, and aluminum areunsatisfactory. After removing test specimens, us
11、e care torestore these storage conditions.DENSITY6. Scope6.1 This test method covers the determination of the densityof magnet-wire enamel in terms of specific gravity or weightper gallon.7. Significance and Use7.1 Density is useful for specification and control purposesduring the manufacture and us
12、e of magnet-wire enamel.1These test methods are under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and are the direct responsibility ofSubcommittee D09.10 on Magnet Wire Insulation.Current edition approved Jan. 1, 2008. Published February 2008. Originallyap
13、proved in 1973. Last previous edition approved in 2003 as D 3288 03.2For 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 onthe ASTM w
14、ebsite.3Withdrawn.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.7.2 The preferred method is Procedure A, hydrometermethod.8. Procedure AHydrometer Method8.1 Determin
15、e the specific gravity of the magnet-wireenamel in accordance with Test Method D 1298 at 25.0 6 0.1C.8.2 If weight per gallon is required, multiply the specificgravity by the weight per gallon of distilled water at the sametemperature (8.31 lb/gal at 25.0 6 0.1 C).9. Procedure BWeight per Gallon Met
16、hod9.1 Determine the weight per gallon of the magnet-wireenamel in accordance with Test Method D 1475 at 25.0 6 0.1C.10. Report10.1 Report the following information:10.1.1 Identification of the magnet-wire enamel, and10.1.2 When using Procedure A, report the specific gravityto the third decimal plac
17、e, or10.1.3 When using Procedure B, report the weight pergallon.FLASH POINT11. Scope11.1 This test method covers the determination of the flashpoint of magnet-wire enamel.12. Terminology12.1 Definitions of Terms Specific to This Test Method:12.2 flash point, of magnet-wire enamel, n the lowesttemper
18、ature at which magnet-wire enamel gives off flammablevapor in sufficient quantity to ignite in air on application of aflame under specified conditions.13. Significance and Use13.1 The flash point reveals the upper temperature limit thatis permissible for storage or use of a magnet-wire enamelwithout
19、 presenting a fire hazard.14. Procedure14.1 Determine the flash point in accordance with TestMethod D56.15. Report15.1 Report the following information:15.1.1 Identification of magnet-wire enamel, and15.1.2 Flash point, degrees Celsius or Fahrenheit, prefer-ably in degrees Fahrenheit.DETERMINED SOLI
20、DS16. Scope16.1 This test method covers the determination of a particu-lar measured value for the solids content in a magnet-wireenamel.17. Terminology17.1 Definitions of Terms Specific to This Test Method:17.2 determined solids, of magnet-wire enamel, ntheportion of a magnet-wire enamel which is no
21、t volatilized whenexposed to specified conditions.18. Significance and Use18.1 Determined solids is one of the critical factors in amagnet-wire enamel that affects film build on a conductor.18.2 The determined solids is also useful for control pur-poses during the manufacture and use of magnet-wire
22、enameland in determining uniformity of batches.18.3 The stack loss (see 27.3) requires the DeterminedSolids value as an input.19. Apparatus19.1 Forced-Convection Oven, capable of maintaining 2006 3 C at the specified specimen location. Refer to Specifica-tion D 5423 Type II for a representative oven
23、.19.2 Weighing Dishes, aluminum, approximately 2 in. (51mm) in diameter, and58 in. (16 mm) height.19.3 Analytical Balance, capable of weighing to 6 0.1 mg.20. Procedure20.1 Preheat dishes to remove oil. Five minutes at 200 6 3C is adequate.20.2 Test a minimum of two specimens.20.3 Place a 2.0 g spec
24、imen (6 0.1 mg) into a taredaluminum dish and weigh immediately.20.4 The weighed specimen must thoroughly cover theentire bottom surface of the weighing dish. Accomplish this bywarming the more viscous materials.20.5 Place the dish and its contents in a 200 6 3Cforced-convection oven for 2 6 0.1 h.2
25、0.6 Remove the dish from the oven and cool to roomtemperature in a desiccator.20.7 Weigh the dish and its contents (6 0.1 mg).21. Report21.1 Report the following information:21.1.1 Ratio of the weight of residue to that of the specimen,expressed as a percentage, as the determined solids content, S,c
26、alculated as follows:S 5Weight of residue/weight of specimen!3100 (1)21.1.2 Number of tests and individual values,21.1.3 Average determined solids of all tests made, and21.1.4 Identification of the magnet-wire enamel.22. Precision and Bias22.1 Precision:22.1.1 The results of all measurements on the
27、sampletypically agree within 6 0.5 %.22.2 Bias:22.2.1 Statements of bias are not applicable in view of theunavailability of a standard reference material for this property.D 3288/D 3288M 082STACK LOSS23. Scope23.1 This test method covers the determination of the stackloss of magnet-wire enamel appli
28、ed toAWG No. 18 (1.02-mm)electrical conductor using an inorganic material as a reference.NOTE 1With other sizes of electrical conductor, expect a variation instack loss. This is particularly true with smaller diameter wire. Expectdifficulty in removing the coating from fine wire.24. Terminology24.1
29、Definitions of Terms Specific to This Test Method:24.2 stack loss, of magnet-wire enamel, n that portion ofthe magnet-wire enamel solids which are lost during theconductor-coating process.25. Significance and Use25.1 The stack loss of magnet-wire enamel will affect theincrease in dimensions, the amo
30、unt of enamel used, the weightincrease, and the economics of applying the enamel to theconductor.26. Apparatus and Reagent26.1 Laboratory Magnet-Wire-Coating Equipment, thatwill duplicate production application conditions and a supplyof bare conductor to be used for the test.26.2 Laboratory Mixer or
31、 Drill Press.26.3 Muffle Furnace, capable of maintaining 600 C.26.4 Oven, forced-convection, capable of maintaining 1106 2.5 C (refer to Specification D 5423 Type II).26.5 Analytical Balance, capable of weighing to the nearest0.1 mg.26.6 Balance, capable of weighing 2 kg (6 1g)26.7 Weighing Bottles,
32、 tall-form cylindrical, glass.26.8 Crucibles, high-form, high-temperature.26.9 Container, at least 2 L in capacity.26.10 Titanium Dioxide (TiO2), meeting the specificationsoutlined in Specification D 476, Type III.27. Procedure27.1 Determine the optimum conditions for applying themagnet-wire enamel
33、using laboratory coating equipment.27.2 Condition the crucible in a muffle furnace maintainedat 600 6 20 C to a constant weight (Note 2), and immediatelyplace it in a desiccator for storage.NOTE 2In practice, crucibles will come to constant weight at 600 C,if held in the muffle furnace for 14 to 16
34、h (overnight).27.3 Measure the determined solids of the magnet-wireenamel in accordance with Sections 16-22, and the ash contentof the solids in accordance with Test Methods D29.27.4 Weigh into the container 1000 6 1 g of the magnet-wire enamel.27.5 Weigh into the container an amount of TiO2equal to
35、the weight (6 1.0 g) of the solids in the 1000-g specimen of themagnet-wire enamel.27.6 Mix the contents in the container until the TiO2iscompletely dispersed in the wire enamel.27.7 Apply this enamel in accordance with 27.1, using thesame conditions and obtaining the same increase in build.Within2h
36、ofapplying the enamel to the conductor, completelystir the enamel to ensure dispersion.27.8 Remove this coating from the wire by snapping andtwisting the wire or by other suitable means. Place the removedcoating in a weighing bottle. For the coatings that are difficultto remove, try chilling the wir
37、e before snapping. In all cases,take care to prevent including any of the metal conductor.27.9 To remove moisture, place the weighing bottle contain-ing the coating in a 110 6 2.5 C forced-convention oven for60 6 2 min.27.10 Remove the weighing bottle and contents from theoven and allow it to cool t
38、o room temperature in a desiccator.27.11 Weigh two conditioned crucibles and weigh into each0.5 to 0.6 g of the dried coating from the weighing bottle. Makeall weighings to the nearest 0.1 mg.27.12 Weigh two conditioned crucibles and weigh into each0.5 to 0.6 g of TiO2.27.13 Place all four crucibles
39、 in the cold muffle furnace.Start the furnace, allowing the temperature to come to 600 Cin1to2h.27.14 Leave the crucibles in the muffle furnace at 600 6 20C until they reach a constant weight (Note 2). Remove thecrucibles and allow them to cool in a desiccator to roomtemperature.27.15 Weigh the cruc
40、ibles.28. Calculation28.1 Calculate the percent stack loss, L, of the magnet-wireenamel as follows:Let F 5 EA!/AB 1 CD! (2)Let R 5 100/F!G F!Then L 5 100 2 Rwhere:A =TiO2mixed with the wire enamel, g,B = percent of TiO2ash, expressed as a decimal,C = solids in the wire-enamel specimen, g,D = percent
41、 ash of the wire-enamel solids, expressed as adecimal,E = weight of ash in the coating specimen, gF = corrected ash weight, g,G = original weight of coating specimen before ashing, g,andR = retention of coating.29. Report29.1 Report the following information:29.1.1 Identification of magnet-wire enam
42、el,29.1.2 Determined solids content of the magnet-wireenamel,29.1.3 Percent ash content of the magnet-wire enamelsolids.29.1.4 Average percent retention of coating to two decimalplaces, and29.1.5 Average percent stack loss to two decimal places.D 3288/D 3288M 08330. Precision and Bias30.1 This test
43、method has been in use for many years, but nostatement of precision has been made and no activity is plannedto develop such a statement.EFFECTIVE SOLIDS31. Scope31.1 This test method covers the determination of thepercentage of liquid enamel that will be retained on the metalconductor in the finishe
44、d product.32. Terminology32.1 Definitions of Terms Specific to This Test Method:32.2 effective solids, of magnet-wire enamel, nthe per-centage of the liquid enamel retained after the removal of thesolvents and the additional oven bakes that simulate the stackloss that occurs during the enameling man
45、ufacturing processfor magnet wire.32.3 evaporative solids, of magnet wire enamels, nthepercentage of liquid enamel that will be retained after removalof the solvents according to step 35.1 of this test procedure.32.4 simulated stack loss, nthe percentage change inevaporative solids after additional
46、lab oven heat exposures asdescribed in step 35.2 of this procedure.33. Significance and Use33.1 In determining the cost of a magnet-wire enamel, onlythat portion of the enamel that is retained on the conductor isof value.34. Procedure34.1 Evaporative Solids:34.1.1 Test a minimum of two specimens.34.
47、1.2 Preheat the aluminum weighing pans to remove oil.Five min at 200 6 3 C is adequate.34.1.3 Remove the pans from the oven and cool to roomtemperature in a desiccator.34.1.4 Measure the tare weight (p) of the dried aluminumpan to an accuracy of 6 0.1 mg.34.1.5 Add 1 6 0.1 grams of liquid magnet wir
48、e enamelinto each tared aluminum weighing pan and measure to anaccuracy of 6 0.1 mg (total of pan and contents = I).34.1.6 Distribute the material evenly over the bottom of thepan.34.1.7 Place the pan and its contents into a forced airconvection laboratory oven for the time and temperaturespecified
49、in Table 1.34.1.8 Remove the pan from the oven and cool to roomtemperature in a desiccator.34.1.9 Weigh the pan and its dried contents (6 0.1 mg).34.1.10 Record these result as W1.34.2 Simulated Stack Loss:34.2.1 Place the pans from 34.1.9 into the additional forcedair convection laboratory ovens for the times and temperaturesspecified in Table 2.NOTE 3When running simulated stack loss, pans do not have to godirectly from one oven to the other. Do not leave the pans in the oven ifyou are changing temperatures.34.2.2 Remove the pans from the oven and
