ASTM D2148-2018 Standard Test Methods for Bondable Silicone Rubber Tapes Used for Electrical Insulation.pdf

1、Designation: D2148 13D2148 18Standard Test Methods forBondable Silicone Rubber Tapes Used for ElectricalInsulation1This standard is issued under the fixed designation D2148; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year

2、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. Scope*1.1 These test methods cover tests for bondable silicone rubber tapes which form a sealed structure either with the ap

3、plicationof heat (and pressure if needed) or by the process of auto-adhesion (self-fusing).1.2 The methods appear in the following sections:Test Method SectionAdhesion 3 9Adhesion 3 10Bond Strength 10 17Bond Strength 11 18Dielectric Breakdown Voltage 18 25Dielectric Breakdown Voltage 19 26Hardness 4

4、0Hardness 41Length 32 and 33Length 33 and 34Thickness 26 31Thickness 27 32Width 35 39Width 36 401.3 The values stated in inch-pound units are to be regarded as standard, except for C. The values in parentheses aremathematical conversions to SI units that are provided for information only and are not

5、 considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of reg

6、ulatory limitations prior to use. For a specific hazard statement see 22.1.123.1.1.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides

7、 and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D149 Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials atCommercial Power FrequenciesD374D374/

8、D374M Test Methods for Thickness of Solid Electrical Insulation (Metric) D0374_D0374MD1000 Test Methods for Pressure-Sensitive Adhesive-Coated Tapes Used for Electrical and Electronic ApplicationsD1458 Test Methods for Fully Cured Silicone Rubber-Coated Glass Fabric and Tapes for Electrical Insulati

9、onD2240 Test Method for Rubber PropertyDurometer HardnessD6054 Practice for Conditioning Electrical Insulating Materials for Testing (Withdrawn 2012)31 These methods are under the jurisdiction of ASTM Committee D09 on Electrical and Electronic Insulating Materials and are the direct responsibility o

10、f SubcommitteeD09.07 on Flexible and Rigid Electrical Insulating Materials.Current edition approved Nov. 1, 2013Nov. 1, 2018. Published November 2013December 2018. Originally approved in 1963. Last previous edition approved in 20082013as D2148 02 (2008)D2148 13.1. DOI: 10.1520/D2148-13.10.1520/D2148

11、-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard i

12、s referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends

13、 that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, We

14、st Conshohocken, PA 19428-2959. United States12.2 ASTM Adjuncts:Tack tester (one drawing)4ADHESION3. Scope3.1 This test method covers the determination of the self-adhesion of unsupported, self-fusing silicone rubber rectangular andtaper-edge (Note 1) tape designed for use as electrical insulation.N

15、OTE 1Taper-edge tape includes such cross sections as triangular, lens, etc.3.2 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Rec

16、ommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.4. Hazards4.1 High Voltage:4.1.1 Lethal voltages are a potential hazard during the performance of this test. It is essential that the test apparatus, and allassociated equipment electrically connected to i

17、t, be properly designed and installed for safe operation.4.1.2 Solidly ground all electrically conductive parts which it is possible for a person to contact during the test.4.1.3 Provide means for use at the completion of any test to ground any parts which were at high voltage during the test or hav

18、ethe potential for acquiring an induced charge during the test or retaining a charge even after disconnection of the voltage source.4.1.4 Thoroughly instruct all operators as to the correct procedures for performing tests safely.4.1.5 When making high voltage tests, particularly in compressed gas or

19、 in oil, it is possible for the energy released atbreakdown to be sufficient to result in fire, explosion, or rupture of the test chamber. Design test equipment, test chambers, andtest specimens so as to minimize the possibility of such occurrences and to eliminate the possibility of personal injury

20、. If thepotential for fire exists, have fire suppression equipment available. See 23.15. Significance and Use5.1 Self-adhesion is a primary initial property since it affects layer-to-layer bonding. The integrity of the bond can significantlyaffect the electrical and physical performance of the insul

21、ation system. Therefore, the degree of self-adhesion is directly relatedto apparatus performance.5.2 A high degree of self-adhesion is desirable for most electrical applications. In this test, a short unwinding length indicatesa high degree of self-adhesion.5.3 This test method has been found useful

22、 as a quality control test for lot acceptance.6. Apparatus6.1 Inclined Mandrel Tack Test Fixture A suggested fixture is shown in Fig. 1.4 The mandrel shall consist of a 58-in.(15.9-mm) diameter aluminum rod mounted in low-friction bearings. Good alignment of bearings is necessary for accurate result

23、s.When properly assembled, the mandrel shall turn freely when loaded with a 1-oz (30-g)(28.5-g) weight suspended from a cottonthread wound in a single layer at the center of the mandrel.6.2 Weights, as specified in Section 78 and means for attachment.6.3 Calibrated stopwatch capable of measuring acc

24、urately to one second.7. Test Specimen7.1 Atest specimen shall consist of two pieces of tape 12 to 15 in. (300(305 to 380 mm) long. Divisions spaced 1 in. (25.4 mm)apart shall be marked off on one piece of tape. If tapes contain an interliner, the interliner shall be removed just prior to wrappingth

25、e mandrel. Dirt and other forms of contamination shall be avoided.8. Procedure8.1 WindingHalf lap the unmarked specimen perfectly on the mandrel of the test fixture, using the suggested weight as shownin Table 1. These weights are not critical. However, they are necessary to get intimate contact and

26、 conformability of the tape. Toobtain perfect half lapping, tilt the tack tester at an appropriate angle as shown in Fig. 1. Wrap the tape on the mandrel at a speedof approximately 18 in. (450(460 mm)/min. Using the winding procedure and weights just described, half lap the marked tape4 Available fr

27、om ASTM International Headquarters. Order Adjunct No. ADJD2148. Original adjunct produced in 1965.D2148 182sample on the mandrel over the first piece of tape. With the winding weight attached, return the test fixture to a horizontal positionand allow the tape to bond for 1 min. Remove the winding we

28、ight from the tape and the handle from the fixture and proceed withthe unwinding test.8.2 UnwindingAfter the tape has bonded for 1 min, attach a load of 21 oz (600 g)/in. (25 mm) of the original tape width (Note2). Attach the weight to the free end of the tape by means of a bulldog paper clamp or ot

29、her suitable device. Release the weightand record the length of tape unwound in 3 min. Although the original 1-in. dimensions will elongate due to the unwind weight,consider each division as one unit. While the winding weights are not critical, the use of proper unwinding weights is mandatory.Consis

30、tent and comparable results depend upon accurate width measurements and the use of the proper unwinding weight.NOTE 2Commercial tapes are usually made to a 6116-in. (61.59- mm) tolerance. Therefore a 600-g weight shall be used for tapes varying in widthfrom 1516 to 1116 in. (23.8 to 27 mm); a 750-g

31、weight shall be used for tapes varying in width from 1316 to 1516 in. (30.2 to 33.3 mm) and a 900-g weightshall be used for tapes varying in width from 1716 to 1916 in. (36.5 to 39.7 mm). Tapes with widths outside these ranges shall be tested in accordancewith their width (determined to the nearest

32、116 in. (1.59 mm). For example, a 118-in. (28.6 mm) wide tape shall be tested with a 675-g weight. Theunwinding weights shall be made to a tolerance of 6 2 %.62 %.9. Report9.1 Report the following information:9.1.1 Description of material, type of cross-section, tape width and thickness,FIG. 1 Incli

33、ned Mandrel Tack Test FixtureTABLE 1 Suggested Winding Weights For 1-in. Wide TapesNOTE 1Winding weights are based on cross-sectional area and havebeen selected to produce approximately the same unit stress on allcross-sections. For tapes of dimensions not listed, use a winding weight ofapproximatel

34、y 10.5 oz (300 g)/0.01 in.2 (6.3 mm2)NoteWinding weights are based on cross-sectional area and have beenselected to produce approximately the same unit stress on all cross-sections.For tapes of dimensions not listed, use a winding weight of approximately 10.5oz (300 g)/0.01 in.2 (6.4 mm2).Tape Thick

35、ness, in. (mm) Weight, oz (g)Triangular Rectangular0.020 (0.51) 0.010 (0.25) 10.5 (300)0.030 (0.76) 0.015 (0.38) 15.8 (450)0.040 (1.02) 0.020 (0.51) 21.0 (600)0.050 (1.27) 0.025 (0.64) 26.4 (750)0.050 (1.27) 0.025 (0.64) 26.3 (750)0.060 (1.52) 0.030 (0.76) 31.7 (900)0.060 (1.52) 0.030 (0.76) 31.5 (9

36、00)0.070 (1.78) . 37.0 (1050)0.070 (1.78) . 36.7 (1050)0.080 (2.03) . 42.3 (1200)0.080 (2.03) . 42.0 (1200)D2148 1839.1.2 Winding weight, in grams,9.1.3 Unwinding weight, in grams, and9.1.4 Length of unwind, to the nearest 14 unit.10. Precision and Bias10.1 This test method has been in use for many

37、years, but no information has been presented to ASTM upon which to base astatement of precision. No activity has been planned to develop such information.10.2 This test method has no bias because the value for adhesion is determined solely in terms of this test method itself.BOND STRENGTH11. Termino

38、logy11.1 Definitions of Terms Specific to This Standard:11.1.1 bond strength, of unvulcanized and semivulcanized supported silicone rubber tapesthe strength of chemical linkagesachieved between successive layers of tape under controlled vulcanizing conditions.12. Significance and Use12.1 The bond st

39、rength is an indication of the physical integrity that can be expected under end use conditions in which theinsulating tapes are applied with an overlap.13. Apparatus13.1 Bonding PressA platen press having the following characteristics:13.1.1 A temperature range to 205 C (400 F). 205C (400F).13.1.2

40、A thermostat that will allow a set temperature to be maintained 6 5 C (6 9 F).6 5C (6 9F).13.1.3 A pressure regulator to allow setting and control of the platen pressure.13.1.4 A pressure indicator to show the pressure being exerted between the platen faces.13.1.5 A timer to allow measurement of bon

41、ding time. It is preferred that a controller-type timer be used which will bothindicate bonding time and also cause the platen pressure to be released and the platens separated at the end of the bonding period.13.2 Temperature-Measuring Device(s) to indicate face temperature of the platen(s).13.3 Si

42、licone Rubber Pad, approximately 18 in. (3.20 mm) thick, 60 to 70 ShoreAdurometer hardness, larger in dimension thanthe specimens to be tested. This is used as a pressure-equalizing device, compensating for irregularities in either the specimen orthe platens.13.4 Polytetrafluoroethylene or suitable

43、release film, three sheets, approximately 2 to 4 mils (0.05 to 0.10 mm) thick. One sheetis placed on each side of the specimens as a release sheet, the third sheet being used to separate the ends of the two test specimens.13.5 Testing MachineA power-driven testing machine of either the cross head or

44、 dead-weight pendulum type. The machineshall be equipped with a tension weighing device having a maximum capacity of 50 lb (22.7 kg) graduated to read 0.1 lb (50 g)or less per scale division.14. Test Specimen14.1 The test specimen shall be selected to be representative of the material to be tested.

45、The size of sample shall be sufficientto give six strips at least 1.25 to 1.5 in. (32 to 38 mm) wide and 6 in. (150 mm) long. Care shall be taken to prevent contamination.15. Conditioning15.1 The specimen shall not be exposed to temperatures above 30 C (85 F) 30C (85F) before bonding. The tests shal

46、l beconducted in the Standard Laboratory Atmosphere as described in Practice D6054.16. Procedure16.1 Cut the strips of material to 1.25 to 1.5 in. (32 to 38 mm) 38 mm) wide and at least 6 in. (150 mm) long, the length beingmeasured in the warp or machine direction of the backing.16.2 Remove any inte

47、rliner material.16.3 Superimpose one strip on another, front side to back side, to form a specimen.16.4 Separate the two strips at one end for a distance of about 1 in. (25 mm) and insert a strip of release film.16.5 Preheat the press to 177 C (350 F).177C (350F).16.6 Assemble the test specimens bet

48、ween two sheets of release film. Place the assembly on the unheated silicone rubber padand insert in the press.D2148 18416.7 Close the press and apply 50 psi (345 kPa) pressure to the specimens for 5 min.16.8 Release the pressure, remove the specimens, and allow them to cool for at least 5 min.16.9

49、Remove the release film and trim the specimens to a 1-in. (25-mm) width.16.10 Clamp one separated end in the upper jaw of the testing machine; peel the other separated end back 180 deg 180 andclamp it in the lower jaw.16.11 Adjust the testing machine to provide a jaw separation rate of 20 in. (500(510 mm) per min. If the pendulum-type machineis used, disengage the pawls during the test. Record the average observed force for each specimen using the technique describedfor adhesion strength in Test Methods D1000.17.