ASTM D5485-2011 Standard Test Method for Determining the Corrosive Effect of Combustion Products Using the Cone Corrosimeter《用锥形腐蚀计测定燃烧制品的腐蚀效应的标准试验方法》.pdf

《ASTM D5485-2011 Standard Test Method for Determining the Corrosive Effect of Combustion Products Using the Cone Corrosimeter《用锥形腐蚀计测定燃烧制品的腐蚀效应的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM D5485-2011 Standard Test Method for Determining the Corrosive Effect of Combustion Products Using the Cone Corrosimeter《用锥形腐蚀计测定燃烧制品的腐蚀效应的标准试验方法》.pdf（16页珍藏版）》请在麦多课文档分享上搜索。

1、Designation:D548510 Designation: D5485 11An American National StandardStandard Test Method forDetermining the Corrosive Effect of Combustion ProductsUsing the Cone Corrosimeter1This standard is issued under the fixed designation D5485; the number immediately following the designation indicates the y

2、ear oforiginal adoption or, in the case of revision, the year 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 This fire-test-response standard measures the corros

3、ive effect by loss of metal from the combustion products of materials,components, or products.1.2 This test method provides corrosion results of product and material specimens limited to a maximum size of 100 by 100mm in area and 50 mm thick.1.3 The results of this test method have not been investig

4、ated with respect to correlation to actual fires.1.4This standard measures and describes the response of materials, products, or assemblies to heat and flame under controlledconditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials,

5、products,or assemblies under actual fire conditions.1.4.1Additional information regarding the targets, the test conditions, and test limitations are provided in the annex.1.5The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. (Se

6、e1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.(See IEEE/ASTM SI-10)1.5 This standard measures and describes the response of materials, products, or assemblies to heat and flame under controlledconditions, but does not b

7、y itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products,or assemblies under actual fire conditions.1.5.1 Additional information regarding the targets, the test conditions, and test limitations are provided in the annex.1.6 Fire testing is inherent

8、ly hazardous. Adequate safeguards for personnel and property shall be employed in conducting thesetests.1.7 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 and

9、health practices and determine the applicability of regulatorylimitations prior to use. For specific hazard statements, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD1711 Terminology Relating to Electrical InsulationD6113 Test Method for

10、 Using a Cone Calorimeter to Determine Fire-Test-Response Characteristics of Insulating MaterialsContained in Electrical or Optical Fiber CablesE176 Terminology of Fire StandardsE1354 Test Method for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen ConsumptionCalorimet

11、erIEEE/ASTM SI-10 Standard for Use of the International System of Units (SI): The Modern Metric System2.2 Other Document:OSHA 191.1450 Occupational Exposure to Hazard Chemicals in Laboratories31This test method is under the jurisdiction of ASTM Committee D09 on Electrical and Electronic Insulating M

12、aterials and is the direct responsibility of SubcommitteeD09.21 on Fire Performance Standards.Current edition approved MarchApril 1, 2010.2011. Published April 2010.2011. Originally approved in 1994. Last previous edition approved in 20092010 asD548509.D548510. DOI: 10.1520/D5485-101.2For referenced

13、ASTM 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.3Available from Occupational Safety and Health Administration (OSHA)/U.S. Dep

14、artmnet of Labor, 200 Constitution Ave., NW, Washington, DC 20210,http:/www.osha.gov.1This 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

15、adequately depict all changes accurately, ASTM recommends 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 standard.Copyright

16、ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method, refer to Terminologies E176 and D1711.3.2 Definitions of Terms Specific to This Standard:3.2.1 cone corrosime

17、ter, nequipment used to determine corrosion in this test method.3.2.2 corrosion-by-metal-loss, nloss of metal of a target expressed as reduction of thickness of the target metal.3.2.3 exposure chamber, nenclosure in which a target is exposed to combustion products.3.2.4 heating flux, nincident power

18、 per unit area that is imposed externally from the heater on the specimen.3.2.4.1 DiscussionThe specimen, once ignited, is also heated by its own flame.3.2.5 sustained flaming, nexistence of flame on or over the surface of the test specimen for periods of4sormore.3.2.5.1 DiscussionFlaming ignition o

19、f less than4sisidentified as transitory flaming or flashing.3.2.6 target, ndetector of known electrical resistance which can lose metal through a process of corrosion when it is exposedto combustion products.3.3 Symbols Specific to This Standard:3.3.1 A0initial corrosion instrument reading.3.3.2 A1c

20、orrosion instrument reading at the end of 1-h exposure to combustion products.3.3.3 A24corrosion instrument reading at the end of 24 h in the environmental chamber.3.3.4 Ccorrosion of a target, nm.3.3.5 C1corrosion at the end of 1-h exposure to combustion products, nm.3.3.6 C24corrosion at the end o

21、f 24 h in the environmental chamber, nm.3.3.7 mspecimen mass, g.3.3.8 mffinal specimen mass, g.3.3.9 miinitial specimen mass, g.3.3.10 m70average 70 % of the total mass loss, g.3.3.11 tdsampling time, s.3.3.12 Tetemperature of the gas in the exposure chamber, C.3.3.13 Vvolumetric sampling rate of co

22、mbustion products, m3/s.4. Summary of Test Method4.1 In this test method, a specimen is subjected to radiant heat. A spark igniter is used to ignite the combustible vapors. Theproducts of decomposition or combustion are channeled through a funnel. A portion of the products continuously flows through

23、an exposure chamber which holds the corrosion targets until the specimen has lost an average 70 % of the total combustible massor for a period of 60 min, whichever is less. The corrosion of the target is determined by exposure of the target to combustionproducts for 1 h, followed by 24-h exposure of

24、 the target to a controlled humidity and temperature environment in a separatechamber. The increase in electrical resistance of each target is monitored, and the reduction in thickness of the metal on the targetis calculated from the increase in electrical resistance. This reduction in thickness is

25、referred to as corrosion-by-metal-loss.4.2 This test method involves the use of a cone corrosimeter as described in Section 7 and shown in Fig. 1.4.3 Alternate equipment found suitable for this test method is the cone calorimeter (see Test Method E1354), with the additionof the gas sampling system d

26、escribed in this test method.5. Significance and Use5.1 The metal loss from corrosion is directly related to the increase in electrical resistance of the target due to the decrease inconductive cross-sectional area.5.2 The relationship between resistance increase of metallic targets used in this tes

27、t method and the amount of metal loss asreported by a uniform loss in thickness has not been determined.5.3 This test method is used to determine the corrosive effect of combustion products from burning electrical insulations orcoverings or their constituent materials or components. Corrosion is det

28、ermined by the reduction of thickness of the metal onstandardized targets, as measured by electrical resistance. These targets are not necessarily representative of the intended end use.5.4 This test method is intended for use in electrical insulations or coverings material and product evaluations,

29、for additionaldata to assist in design of electrical insulations or coverings products, or for development and research of electrical insulations orcoverings products.5.5 A value of the heating flux is selected to be relevant to the fire scenario being investigated (up to 100 kW/m2). Additionalinfor

30、mation for testing is given in A1.2.3.6. Interferences6.1 Discard the test data if any of the following occur:6.1.1 Leakage occurs between the sampling point and the exit of the exposure chamber which could cause a dilution of gases.6.1.2 The specimen swells sufficiently prior to ignition to touch t

31、he spark plug or swells into the plane of the heater base plateduring combustion.D5485 1126.1.3 The specimen drips off the specimen holder or falls out of the specimen holder such that the specimen is not subjectedto the test exposure conditions.6.1.4 There is highly localized corrosion of the targe

32、t, indicating a defective target.6.1.5 There is visual degradation of the reference circuit by the attack of combustion products on or under the protective coating.7. Apparatus7.1 General:7.1.1 This test method uses the cone corrosimeter described in 7.1.3. Alternatively, the cone calorimeter test e

33、quipment isacceptable provided that it is equipped with a gas sampling system as described in 7.8. If the cone calorimeter is used to assessthe fire properties of insulating materials contained in electrical or optical fiber cables, the test shall be conducted in accordancewith Test Method D6113, wh

34、ich was developed specifically for that purpose.7.1.2 The dimensions of the cone corrosimeter specimen holder and additional equipment used in collection of gas samples aregiven in Figs. 1-11 and also stated in the following description.7.1.3 The cone corrosimeter consists of the following main comp

35、onents: conical-shaped radiant electric heater; temperaturecontroller; load cell; electric ignition spark plug; heat-flux gage; exhaust system; specimen holder; and the gas sampling system.FIG. 1 Cone CorrosimeterFIG. 2 Cross-Section View Through the HeaterD5485 113Other essential elements needed to

36、 measure corrosion are a corrosion target and a device to measure corrosion (see 7.9).Ageneralview of the cone corrosimeter is shown in Fig. 1.7.2 Conical Heater:7.2.1 The active element of the heater consists of an electrical heater rod, rated at 5000 W at 240 V, tightly wound into the shapeof a tr

37、uncated cone (Fig. 2). The heater is encased on the outside with a double-wall stainless steel cone, and packed with arefractory fiber material of approximately 100-kg/m3density.7.2.2 The heater is capable of producing heating flux on the surface of the specimen of up to 100 kW/m2with a uniformity o

38、f62 % within the central 50 by 50-mm area of the specimen.7.2.3 The heating flux from the heater is held at a preset level by means of a temperature controller and three Type Kstainless-steel-sheathed thermocouples having an outside diameter of 1.71.5 to 1.6 mm with an unexposed hot junction.Alterna

39、tively, either 3-mm outside diameter sheathed thermocouples with an exposed hot junction, or 1-mm outside diametersheathed thermocouples with an unexposed hot junction are suitable. They are symmetrically disposed and in contact with, but notwelded to, the heater element (see Fig. 2).The thermocoupl

40、es are of equal length and wired in parallel to the temperature controller.FIG. 3 Exhaust SystemFIG. 4 Exploded View of Load Cell and Cone Radiant HeaterD5485 1147.3 Temperature Controller:7.3.1 The temperature controller for the heater is to hold the element temperature steady to within 62C.Asuitab

41、le temperaturecontroller system is a “3-term” controller (proportional, integral, and derivative) with a thyristor unit capable of switching currentsup to 25 A at 240 V.7.3.2 The controller has a temperature input range from 0 to 1000C; a set scale with a resolution of 2C; and automatic coldjunction

42、 compensation.The controller is equipped with a safety feature such that in the event of an open circuit in the thermocoupleline, it will cause the temperature to fall to near the bottom of its range.7.3.3 The temperature controller uses a zero-crossing-type thyristor unit.7.3.4 The heater temperatu

43、re is monitored by a meter with a resolution of 2C.7.4 Exhaust System:7.4.1 The exhaust-gas system consists of a high-temperature centrifugal exhaust blower, a hood, intake and exhaust ducts forthe fan, and an orifice plate flowmeter (Fig. 3).7.4.2 The flow rate is determined by measuring the differ

44、ential pressure across a sharp-edged orifice (57-mm inside diameter)in the exhaust stack, at least 350 mm downstream from the fan.7.4.3 In other details, the geometry of the exhaust system is not critical. Where necessary, small deviations from therecommended dimensions given in Fig. 3 are allowed.

45、For example, it is permissible for the inner diameter of the duct and theorifice plate to be slightly different (tolerance: 62 mm). The location of the fan in Fig. 3 shall be between 900 and 1200 mmdownstream of the hood. Flow through the fan ensures adequate mixing, which is essential to the test.7

46、.5 Load CellThe general arrangement of the load cell with the conical heater is shown in Fig. 4. Use a load cell with anaccuracy of 0.1 g, a measuring range of at least 500 g, and a mechanical tare adjustment range of 3.5 kg.NOTE 1All dimensions are in millimetres.NOTE 2* Indicates a critical dimens

47、ion.FIG. 5 First Specimen HolderD5485 1157.6 Specimen Holder and Mounting:7.6.1 Two specimen holders are described, one in 7.6.2-7.6.4 and one in 7.6.5.7.6.2 The first specimen holder is shown in Fig. 5. The bottom is constructed from 2.4-mm nominal stainless steel and hasoutside dimensions of 106 b

48、y 106 by 25-mm height (62 mm).7.6.2.1Optionally, use an edge frame and a grid. The optional edge frame (7.6.2.1 An open stainless steel square, 59 mm in inside dimensions, shall be spot welded to the underside of the horizontalNOTE 1All dimensions are in millimetres.NOTE 2* Indicates a critical dime

49、nsion.FIG. 6 Optional Edge FrameD5485 116specimen holder to facilitate the centering of the specimen under the cone heater. The leading edge of the open square underneaththe specimen holder, which is the one opposite the handle, is optional. The open square on the bottom of the specimen holder shallbe designed to seat with the sample mount assembly located at the top of the load cell, ensuring that the specimen holder is centeredwith respect to the cone heater.7.6.2.2 Optionally, use an edge frame and a grid. The optional edge frame (Fig. 6)