1、Designation: D6194 10An American National StandardStandard Test Method forGlow-Wire Ignition of Materials1This standard is issued under the fixed designation D6194; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. 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 This test method covers the minimum temperaturerequired to ignite insulating materials using a glowing heatsource. In a pre
3、liminary 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 This
4、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 he
5、at 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 asstandard. No other units of measurement
6、 are included in thisstandard. (See IEEE/ASTM SI-10 for 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
7、the applica-bility of regulatory limitations prior to use. For specificprecautionary statements, see Section 9.1.7 Fire testing is inherently hazardous. Adequate safe-guards for personnel and property shall be employed inconducting these tests.NOTE 1Although this test method and IEC 60695-2-13 diffe
8、r inapproach and in detail, data obtained using either are technically equiva-lent.2. Referenced Documents2.1 ASTM Standards:2D1711 Terminology Relating to Electrical InsulationE176 Terminology of Fire StandardsE220 Test Method for Calibration of Thermocouples ByComparison TechniquesE230 Specificati
9、on and Temperature-Electromotive Force(EMF) Tables for Standardized ThermocouplesIEEE/ASTM SI-10 International System of Units (SI), TheModernized Metric System2.2 IEC Standard:IEC 60695-4 Fire Hazard TestingPart 4: TerminologyConcerning Fire Tests3IEC 60695-2-12 Fire Hazard TestingPart 212: Glowing
10、/Hot-Wire Based Test MethodsGlow-Wire FlammabilityTest Method for Materials3IEC 60695-2-13 Fire Hazard TestingSection 20:Glowing/Hot-Wire Based Test MethodsGlow-Wire CoilIgnitability Test Method for Materials32.3 ISO Standard:ISO 13943 Fire SafetyVocabulary43. Terminology3.1 Definitions:3.1.1 Use Te
11、rminology E176, ISO 13943, and IEC 60695-4for definitions of terms used in this test method and associatedwith fire issues. Where differences exist in definitions, thosecontained in Terminology E176 shall be used. Use Terminol-ogy D1711 for definitions of terms used in this test method andassociated
12、 with electrical insulation materials.3.2 Definitions of Terms Specific to 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.1This test method
13、 is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.21 on Fire Performance Standards.Current edition approved March 1, 2010. Published April 2010. Originallyapproved in 1997. Last previous edition appro
14、ved in 2008 as D619408. DOI:10.1520/D6194-10.2For 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 website.3Available from
15、International Electrotechnical Commission (IEC), 3 rue deVaremb, Case postale 131, CH-1211, Geneva 20, Switzerland, http:/www.iec.ch.4Use undyed, soft, strong, lightweight tissue paper weighing between 12 and 30g/m2.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM In
16、ternational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.2 glow-wire flammability index (GWFI), nthe highesttest temperature, during three subsequent tests for a testspecimen of a given thickness, at which one of the followingconditions are fulfilled: a) f
17、lames or glowing of the testspecimen extinguish within 30 s after removal of the glow-wireand there is no ignition of the wrapping tissue placed under-neath the test specimen; b) there is no ignition of the testspecimen.3.2.3 glow-wire ignition temperature (GWIT), nthe tem-perature which is 25 C (30
18、 C between 900 and 960 C)higher than the GWFI.3.2.4 ignition, ninitiation of combustion.3.2.4.1 DiscussionIgnition is deemed to have taken placewhen the first of the following occurs: sustained flaming on thetest specimen surface for over5sorfalling particles causingthe appearance of flames on a tis
19、sue paper placed underneaththe test specimen.4. Summary of Test Method4.1 In this test method, a standardized test specimen (eithersquare or round), is supported vertically and is exposed toelectrical heating from a glow-wire set at pre-determinedtemperatures. The minimum temperature for glow-wire i
20、gni-tion is assessed through testing at incremental temperatures.5. Significance and Use5.1 During operation of electrical equipment, includingwires, resistors, and other conductors, it is possible for over-heating to occur under certain conditions of operation, or whenmalfunctions occur. When this
21、happens, a possible result isignition of the adjacent insulation material.5.2 This test method assesses the susceptibility of electricalinsulating materials to ignition as a result of exposure to aglowing wire.5.3 This test method determines the minimum temperaturerequired to ignite a material by th
22、e effect of a glowing heatsource, under the specified conditions of test.5.4 This method is suitable, subject to the appropriatelimitations of an expected precision of 615 %, to categorizematerials.5.5 In this procedure, the specimens are subjected to one ormore specific sets of laboratory condition
23、s. If different testconditions are substituted or the end-use conditions arechanged, it is not always possible by or from this test to predictchanges in the fire-test-response characteristics measured.Therefore, the results are valid only for the fire test exposureconditions described in this proced
24、ure.6. Apparatus6.1 Glow-WireThe glow-wire shall be a Nichrome(Nickel-Chrome) wire, that is iron free, with the followingnominal properties: a wire composition of 20 % chromium-80 % nickel, a diameter of 4 mm, and it shall be formed to thedimensions shown in Fig. 1.NOTE 1All dimensions in millimetre
25、s.FIG. 1 Glow-Wire and Positioning of the ThermocoupleD6194 1026.2 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 welded point located inside the sheath, for measuringt
26、he 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 sheathtemperatures of at least 1050 C. Arrange the thermoc
27、ouple 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 thesheathed thermocouple in place. Ensure that the thermocouplefollows the movement of the tip of the glow-wire resul
28、tingfrom elongation caused by thermal heating.6.3 Temperature IndicatorUse a temperature indicator forType K thermocouples capable of reading up to 1000 C.Calibrate the combination thermocouple and temperature indi-cator in accordance with the general procedures outlined inTest Method E220. The init
29、ial calibration tolerance is definedin the tables of Specification and Temperature-ElectromotiveForce (EMF) Tables E230.6.4 Supply CircuitThe supply circuit shall be capable ofsupplying up to 150 A at 2.1V, with smooth continuousadjustment of voltage to provide the required current as neededto maint
30、ain 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 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
31、 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 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
32、 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 positivelyvented to the outside of the test facility before and after the test,but it shall remain closed and unvented during the test. Thechamber shall b
33、e equipped with an observation window.7. Test Specimen7.1 Prepare square specimens that are approximately 60 360 mm or round specimens that are approximately 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
34、this test method. Generally, ten specimens willsuffice to complete the procedure specified in Section 9.8. Conditioning8.1 Condition specimens, test board and tissue paper at 236 2 C and 50 6 5 % relative humidity for at least 40 h priorto testing.FIG. 2 Test Apparatus (Example)D6194 1039. Safety Pr
35、ecautions9.1 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 ofcombustion and exhaust them from the test chamber after eachrun.9.2 Take precautions to safeguard the health of pers
36、onnelagainst 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. Procedure10.1 Before each test, clean the tip of the glow-wire with awire brush to remove any residue left from
37、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 isvertical and any heat losses to the supporting means areinsignificant. Adjust the equipment so the depth of penetrationis limited to 7 mm below the surface
38、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 heat the glow-wire to the pre-determined temperature. Use the calibrated thermocouple torecord the glow-wire temperature. Maintain the pre-selectedglo
39、w-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 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
40、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 flaming 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 place
41、d underneath the apparatusexhibits flames caused by particles falling from the testspecimen.10.5.1 If ignition occurs, repeat the test with a new testspecimen, and at a temperature 50 C lower than that usedduring the previous test. If the resulting temperature hasalready been used, do not retest at
42、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 previous test. If the resulting temperature hasalready been used, do not retest at that temperature.10.6 When a maximum temperature has been determined
43、,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 maximum test temperature whichwill not cause ignition during three consecutive tests.10.7 The glow-wire ignition temperature is that temperaturethat is
44、 25 C higher than the highest temperature at which thetip of the glow-wire does not cause ignition during threeconsecutive tests.10.8 The glow-wire flammability index (GWFI) is thehighest test temperature, during three subsequent tests for a testspecimen of a given thickness, at which one of the fol
45、lowingconditions are fulfilled:10.8.1 Flames or glowing of the test specimen extinguishwithin 30 s after removal of the glow wire and there is noignition of the wrapping tissue placed underneath the testspecimen.10.8.2 There is no ignition of the test specimen.11. Report11.1 Report the following inf
46、ormation:11.1.1 Complete identification of the material tested includ-ing type, source, and manufacturers code number,11.1.2 Thickness of specimens tested,11.1.3 The glow-wire ignition temperature, and11.1.4 The glow-wire flammability index.12. Precision and Bias12.1 PrecisionIt is not possible to s
47、pecify the precision ofthe 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 measuri
48、ng the glow-wireignition 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 materialsD6194 104SUMMARY OF CHANGESCommittee D09 has identified the locati
49、on of selected changes to this test method since the last issue,D619408, that may impact the use of this test method. (Approved March 1, 2010)(1) Revised 1.7.ASTM International takes no position respecting the validity of any patent rights asserted 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
