1、Designation: D 6194 04An American National StandardStandard Test Method forGlow-Wire Ignition of Materials1This standard is issued under the fixed designation D 6194; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 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. Scope1.1 This test method covers the minimum temperaturerequired to ignite insulating materials using a glowing heatsource. In a p
3、reliminary fashion, this test method differentiatesbetween the susceptibilities of different materials with respectto their resistance to ignition due to an electrically-heatedsource.1.2 This test method applies to molded or sheet materialsavailable in thicknesses ranging from 0.25 to 6.4 mm.1.3 Thi
4、s test method is not valid for determining the ignitionbehavior of complete electrotechnical equipment, since thedesign of the electrotechnical product influences the heattransfer between adjacent parts.1.4 This test method measures and describes the response ormaterials, products, or assemblies to
5、heat and flame undercontrolled conditions, but does not by itself incorporate allfactors required for fire hazard or fire risk assessment of thematerials, products, or assemblies under actual fire conditions.1.5 The values stated in SI units are to be regarded as thestandard. (See IEEE/ASTM SI-10 fo
6、r further details.)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
7、use. For specificprecautionary statements, see Section 9.1.7 Fire testing of products and materials is inherentlyhazardous, and adequate safeguards for personnel and propertyshall be employed in conducting these tests. Fire testinginvolves hazardous materials, operations, and equipment.NOTE 1Althoug
8、h this test method and IEC 60695-2-13 differ inapproach and in detail, data obtained using either are technically equiva-lent.2. Referenced Documents2.1 ASTM Standards:2D 1711 Terminology Relating to Electrical InsulationE 176 Terminology of Fire StandardsE 220 Test Method for Calibration of Thermoc
9、ouples byComparison TechniquesE 230 Specification and Temperature-Electromotive Force(EMF) Tables for Standardized ThermocouplesIEEE/ASTM SI-10 International System of Units (SI), TheModernized Metric System2.2 IEC Standard:IEC 60695-2-13: Fire Hazard TestingSection 20:Glowing/Hot-Wire Based Test Me
10、thodsGlow-Wire CoilIgnitability Test Method for Materials3IEC 60695-4: Fire Hazard TestingPart 4: TerminologyConcerning Fire Tests32.3 ISO Standard:ISO 13943: Fire SafetyVocabulary43. Terminology3.1 Definitions:3.1.1 Use Terminology E 176, ISO 13943, and IEC 60695-4for definitions of terms used in t
11、his test method and associatedwith fire issues. Where differences exist in definitions, thosecontained in Terminology E 176 shall be used. Use Terminol-ogy D 1711 for definitions of terms used in this test method andassociated with electrical insulation materials.3.2 Definitions of Terms Specific to
12、 This Standard:3.2.1 glow wire, na wire of specified dimensions that canbe controllably-heated electrically to determine ignitability of amaterial.3.2.1.1 DiscussionFig. 1 shows a glow wire and itspositioning.3.2.2 ignition, ninitiation of combustion.1This test method is under the jurisdiction of AS
13、TM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.21 on Fire Performance Standards.Current edition approved Sept. 1, 2004. Published September 2004. Originallyapproved in 1997. Last previous edition approved in 2003 as D 6194 03.2Fo
14、r 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 website.3Available from International Electrotechnical Commission (IEC),
15、 3 Rue deVarembe, Geneva, Switzerland.4Use undyed, soft, strong, lightweight tissue paper weighing between 12 and 30g/m2.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.2.1 DiscussionIgnition is deemed to have taken placewhen the
16、 first of the following occurs: sustained flaming on thetest specimen surface for over5sorfalling particles causingthe appearance of flames on a tissue paper placed underneaththe test specimen.4. Summary of Test Method4.1 In this test method, a standardized test specimen (eithersquare or round), is
17、supported vertically and is exposed toelectrical heating from a glow-wire set at pre-determinedtemperatures. The minimum temperature for glow-wire igni-tion is assessed through testing at incremental temperatures.5. Significance and Use5.1 During operation of electrical equipment, includingwires, re
18、sistors, and other conductors, it is possible for over-heating to occur under certain conditions of operation, or whenmalfunctions occur. When this happens, a possible result isignition of the adjacent insulation material.5.2 This test method assesses the susceptibility of electricalinsulating mater
19、ials to ignition as a result of exposure to aglowing wire.5.3 This test method determines the minimum temperaturerequired to ignite a material by the effect of a glowing heatsource, under the specified conditions of test.5.4 This method is suitable, subject to the appropriatelimitations of an expect
20、ed precision of 615 %, to categorizematerials.5.5 In this procedure, the specimens are subjected to one ormore specific sets of laboratory conditions. If different testconditions are substituted or the end-use conditions arechanged, it is not always possible by or from this test to predictchanges in
21、 the fire-test-response characteristics measured.Therefore, the results are valid only for the fire test exposureconditions described in this procedure.6. Apparatus6.1 Glow-WireThe glow-wire shall be a Nichrome(Nickel-Chrome) wire, that is iron free, with the followingnominal properties: a wire comp
22、osition of 20 % chromium-80 % nickel, a diameter of 4 mm, and it shall be formed to thedimensions shown in Fig. 1.6.2 ThermocoupleUse Type K sheathed fine-wire thermo-couple, having an overall diameter of 1.0 mm max, and wiressuitable for continuous operation at temperatures up to 960 C,with the wel
23、ded point located inside the sheath, for measuringthe temperature of the glow-wire. Examples of suitable wirecompositions are Nickel-Chromium (NiCr) and Nickel-Aluminum (NiAl).6.2.1 Construct the thermocouple sheath of a metal that willallow the thermocouple to perform its function in air at sheatht
24、emperatures of at least 1050 C. Arrange the thermocouple isarranged in a pocket hole, drilled in the tip of the glow-wire, asshown in Fig. 1. Maintain the thermal contact between thewalls of the bored hole in the glow-wire by pinning theNOTE 1All dimensions in millimetres.FIG. 1 Glow-Wire and Positi
25、oning of the ThermocoupleD6194042sheathed thermocouple in place. Ensure that the thermocouplefollows the movement of the tip of the glow-wire resultingfrom elongation caused by thermal heating.6.3 Temperature IndicatorUse a temperature indicator forType K thermocouples capable of reading up to 1000
26、C.Calibrate the combination thermocouple and temperature indi-cator in accordance with the general procedures outlined inTest Method E 220. The initial calibration tolerance is definedin the tables of Specification and Temperature-ElectromotiveForce (EMF) Tables E 230.6.4 Supply CircuitThe supply ci
27、rcuit shall be capable ofsupplying up to 150 A at 2.1V, with smooth continuousadjustment of voltage to provide the required current as neededto maintain the desired glow-wire tip temperature.6.5 Test FixtureAs shown in Fig. 2, the test fixture shallbe capable of holding the glow-wire in a horizontal
28、 plane andmoving it against the vertical test specimen, maintaining aforce of 1.0 6 0.2 N over a distance of at least 7 mm.NOTE 2A weight of 100 6 20 g, as shown in Fig. 2, will provide therequired force.6.6 Indicator BoardUse as indicator a flat pine woodboard with a smooth finish, approximately 10
29、 mm thick, and inclose contact with a single layer of tissue paper,4located at adistance of 200 6 5 mm below the glow-wire tip.6.7 Test ChamberUse as a test chamber a closed draft-freechamber that permits observation of the specimen and has avolume of at least 0.3 m3. The test chamber shall be posit
30、ivelyvented to the outside of the test facility before and after the test,but it shall remain closed and unvented during the test. Thechamber shall be equipped with an observation window.7. Test Specimen7.1 Prepare square specimens that are approximately 60 360 mm or round specimens that are approxi
31、mately 60 mm indiameter, and of a thickness commonly encountered in prac-tice. Thicknesses less than 0.25 mm or greater than 6.4 mm arenot valid for this test method. Generally, ten specimens willsuffice to complete the procedure specified in Section 9.8. Conditioning8.1 Condition specimens, test bo
32、ard and tissue paper at 236 2 C and 50 6 5 % relative humidity for at least 40 h priorto testing.9. Safety Precautions9.1 It is possible that fumes and products of incompletecombustion are liberated from the specimen when conductingthis test. Avoid the inhalation of such fumes and products ofcombust
33、ion and exhaust them from the test chamber after eachrun.9.2 Take precautions to safeguard the health of personnelagainst the risk of explosion or fire, the inhalation of smoke, orother products of combustion, or the exposure to the residuespotentially remaining on the specimen after testing.10. Pro
34、cedure10.1 Before each test, clean the tip of the glow-wire with awire brush to remove any residue left from previously testedmaterials.10.2 Mount the specimen in the test fixture so that thesurface that comes in contact with the tip of the glow-wire isFIG. 2 Test Apparatus (Example)D6194043vertical
35、 and any heat losses to the supporting means areinsignificant. Adjust the equipment so the depth of penetrationis limited to 7 mm below the surface of the specimen. Shieldthe specimen during the heating of the glow-wire.10.3 Close the chamber vents and doors, making the testchamber draft free and he
36、at the glow-wire to the pre-determined temperature. Use the calibrated thermocouple torecord the glow-wire temperature. Maintain the pre-selectedglow-wire temperature for at least 60 s prior to conducting thetest.10.4 Bring the specimen in contact with the tip of theglow-wire at an applied force of
37、1.0 6 0.2 N for 30 6 1s.NOTE 3The glow-wire temperature will decrease when the tip con-tacts the test specimen.10.5 Observe to see whether ignition occurs during theapplication of the glow-wire (see 3.2.1). For the purposes ofthis test, ignition will be deemed to have occurred if eithersustained fla
38、ming occurs (appearance of a flame on the surfaceof the test specimen which lasts for more than 5 s) or the tissuepaper on the indicator board placed underneath the apparatusexhibits flames caused by particles falling from the testspecimen.10.5.1 If ignition occurs, repeat the test with a new testsp
39、ecimen, and at a temperature 50 C lower than that usedduring the previous test. If the resulting temperature hasalready been used, do not retest at that temperature.10.5.2 If ignition does not occur, repeat the test with a newtest specimen, and at a temperature 50 higher than that usedduring the pre
40、vious test. If the resulting temperature hasalready been used, do not retest at that temperature.10.6 When a maximum temperature has been determined,following the procedure in 10.5, repeat the test with a new testspecimen with a temperature interval of 25 C, in the finalapproach to determine the max
41、imum test temperature whichwill not cause ignition during three consecutive tests.10.7 The glow-wire ignition temperature is that temperaturethat is 25 C higher than the highest temperature at which thetip of the glow-wire does not cause ignition during threeconsecutive tests.11. Report11.1 Report t
42、he following information:11.1.1 Complete identification of the material tested includ-ing type, source, and manufacturers code number,11.1.2 Thickness of specimens tested, and11.1.3 The glow-wire ignition temperature.12. Precision and Bias12.1 PrecisionIt is not possible to specify the precision oft
43、he procedure in this test method for measuring the glow-wireignition temperature because insufficient data has been devel-oped and compiled for a reliable statistical analysis.12.2 BiasNo information can be presented on the bias ofthe procedure in this test method for measuring the glow-wireignition
44、 temperature because no material having an acceptablereference value is available.13. Keywords13.1 electrically heated sources; flame; glow-wire; ignitabil-ity; ignition; plastic electrical insulating materialsASTM International takes no position respecting the validity of any patent rights asserted
45、 in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the
46、 responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive c
47、areful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM Internati
48、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may 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).D6194044
