1、Designation: D2155 12Standard Test Method forDetermination of Fire Resistance of Aircraft Hydraulic Fluidsby Autoignition Temperature1This standard is issued under the fixed designation D2155; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、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. Scope1.1 This test method is used for assessing the fire resistanceof hydraulic fluids used for aircraft
3、applications by determina-tion of the autoignition temperature of the hydraulic fluid in airat one atmosphere pressure using hypodermic syringe injec-tion.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units
4、that are provided for information onlyand are not considered standard.1.3 This standard is used to measure and describe theresponse of materials, products, or assemblies to heat andflame under controlled conditions, but does not by itselfincorporate all factors required for fire hazard or fire riska
5、ssessment of the materials, products, or assemblies underactual fire conditions.1.4 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 det
6、ermine the applica-bility of regulatory limitations prior to use.2. Summary of Test Method2.1 A small metered sample of the fluid to be tested isinjected with a hypodermic syringe into a heated 200-mLErlenmeyer borosilicate glass flask containing air. The contentsof the flask are observed in a darke
7、ned room for 5 minfollowing injection of the sample or until autoignition occurs;autoignition is evidenced by the sudden appearance of a flameinside the flask. The lowest flask temperature at which autoi-gnition occurs for a series of prescribed sample volumes istaken to be the autoignition temperat
8、ure of the fluid in air atone atmosphere pressure.3. Apparatus3.1 The apparatus, shown schematically in Figs. 1 and 2,shall conform to the requirements prescribed in 3.2 to 3.6.3.2 FurnaceThe furnace shall consist of a 5-in. (127-mm)internal diameter alundum cylinder, 5 in. long, circumferen-tially
9、wound with an electric heater, a Transite cover ring neckheater, three-neck heater supports, Transite flask guide ring,base heater, and suitable refractory insulating material andretaining shell. Temperature control shall be achieved by theuse of suitable autotransformers or rheostats, thermocouples
10、,and a suitable potentiometer.3.3 Hypodermic SyringeA 0.25 or 1-cm3hypodermicsyringe equipped with a 2-in. (50.8-mm) No. 18 stainless steelneedle and calibrated in units of 0.01 cm3should be used toinject the sample into the heated test flask.3.4 Test FlaskThe test flask in Fig. 3 shall be a commer-
11、cial 200-mL Erlenmeyer borosilicate glass flask.2A new flaskshall be used for tests on each product; should the flask becomevisibly coated with residue before the completion of tests oneach product, the final series of tests should be conducted witha new flask.3.5 ThermocouplesThree calibrated 20-ga
12、ge iron-constantan thermocouples shall be used in determining theflask temperature. These shall be mounted in the furnace so asto contact the walls of the flask 1 and 2 in. (25 to 51 mm) belowthe bottom of the neck heater and under the base of the flasknear its center.3.6 TimerAn electric timer or s
13、topwatch calibrated in 0.1or 0.2-s intervals shall be used to determine the time lag beforeignition (time interval between the instant of sample injectionand that of ignition as evidenced by the appearance of theflame).4. Procedure4.1 Temperature ControlAdjust the temperature of thefurnace so that t
14、he temperatures at the top, center, and bottom1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.N0 on Hydraulic Fluids.Current edition approved July 1, 2012. Published November 2012. Originallyapp
15、roved in 1966. Last previous edition approved in 1976 as D2155-66(1976)which was withdrawn August 1980 and reinstated in July 2012. DOI: 10.1520/D2155-122The sole source of supply of the apparatus known to the committee at this timeis Schott of North America Inc., 555 Taxter Road, Elmsford, NY. If y
16、ou are awareof alternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Co
17、nshohocken, PA 19428-2959. United States1FIG. 1 Furnace DetailsD2155 122of the 200-mL Erlenmeyer test flask are within 2F (1.1C) ofthe desired test temperature.4.2 Sample InjectionInject 0.07 cm3of the sample to betested into the test flask with the hypodermic syringe; quicklywithdraw the syringe.4.
18、3 Time MeasurementStart the timer as the sample isinjected into the test flask.4.4 ObservationsObserve the inside of the test flask in adarkened room by means of a mirror placed at an appropriateangle above the flask. If a flame is not observed in 5 min, thevolume of the sample tested is considered
19、nonflammable at thetemperature of the test flask. Completely flush the flask withclean dry air and stop the timer. Then repeat the test at a higher(about 50F or 30C) temperature. Allow at least 15 min toelapse between tests. If a flame is observed, stop the timer andrecord the time interval between
20、the sample injection and theappearance of the flame to the nearest 0.2 s as the time lag.Lower the test temperature by 5F (3C) and repeat the entireprocedure until autoignition is no longer obtained. Then raisethe test temperature about 50F and repeat the above procedureusing 0.10 cm3of the sample.
21、If the lowest temperature atwhich autoignition is obtained with this quantity of sample(0.10 cm3) is lower than that found in the previous test, repeatFIG. 2 Furnace Heaters and SupportsD2155 123the procedure again using 0.12, then 0.15 cm3, etc., of thesample in 0.02 to 0.03 cm3steps until the mini
22、mum autoigni-tion temperature is obtained. If the lowest temperature at whichautoignition is obtained with 0.10 cm3of the sample is greaterthan that obtained with 0.07 cm3of the sample, repeat theabove procedure with 0.05 then 0.03 cm3instead of 0.12,0.15 cm3, etc.4.5 AutoignitionAutoignition is usu
23、ally evidenced inthese tests by the appearance of a yellow or blue flame.However, pale blue, white, red, and mixed color flames may beobtained in some cases.4.6 DataRecord the test temperature, pressure, quantity ofsample used, and time lag before ignition. A plot of the ignitiontemperature against
24、time lag before ignition may be used todetermine the autoignition temperature, if desired.5. Report5.1 Report as the autoignition temperature the lowest flasktemperature at which autoignition was obtained, rounded to thenearest 5F (3C); report the corresponding time lag beforeignition and barometric
25、 pressure as the time lag and pressure,respectively.FIG. 3 200 mL Erlenmeyer Flask, Narrow NeckD2155 1246. Precision and Bias6.1 The following criteria should be used for judging theacceptability of results (95 percent confidence):6.1.1 RepeatabilityDuplicate results by the same operatorshould be co
26、nsidered suspect if they differ by more than 5Fbelow 600F (316C) and by more than 10F above 600F.6.1.2 ReproducibilityThe result submitted by each of twolaboratories should be considered suspect if the two resultsdiffer by more than 20F below 600F and by more than 40Fabove 600F.7. Keywords7.1 aircra
27、ft hydraulic fluids; autoignition temperature; fireresistanceASTM 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 p
28、atent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited e
29、ither for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fai
30、r hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this sta
31、ndard 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D2155 125
