ASTM_D_2155_-_12.pdf

Designation:D215512Standard 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 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 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 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 riskassessment 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 determine 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 darkened 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 temperature 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 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,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-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 ThermocouplesThreecalibrated20-gageiron-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 stopwatch 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 the 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.Originallyapproved 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 you 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 Conshohocken,PA 19428-2959.United States1 FIG.1 Furnace DetailsD2155 122 of 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;