1、Designation: D3241 14a An American National StandardDesignation 323/99Standard Test Method forThermal Oxidation Stability of Aviation Turbine Fuels1This standard is issued under the fixed designation D3241; the number immediately following the designation indicates the year oforiginal adoption or, i
2、n 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope
3、*1.1 This test method covers the procedure for rating thetendencies of gas turbine fuels to deposit decompositionproducts within the fuel system.1.2 The differential pressure values in mm Hg are definedonly in terms of this test method.1.3 The deposition values stated in SI units shall be re-garded
4、as the referee value.1.4 The pressure values stated in SI units are to be regardedas standard. The psi comparison is included for operationalsafety with certain older instruments that cannot report pres-sure in SI units.1.5 No other units of measurement are included in thisstandard.1.6 WARNINGMercur
5、y has been designated by manyregulatory agencies as a hazardous material that can causecentral nervous system, kidney and liver damage. Mercury, orits vapor, may be hazardous to health and corrosive tomaterials. Caution should be taken when handling mercury andmercury containing products. See the ap
6、plicable product Ma-terial Safety Data Sheet (MSDS) for details and EPAswebsitehttp:/www.epa.gov/mercury/faq.htmfor addi-tional information. Users should be aware that selling mercuryand/or mercury containing products into your state or countrymay be prohibited by law.1.7 This standard does not purp
7、ort 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. For specificwarning statements, see 6.1.1, 7.
8、2, 7.2.1, 7.3, 11.1.1, andAnnex A5.2. Referenced Documents2.1 ASTM Standards:2D1655 Specification for Aviation Turbine FuelsD4306 Practice for Aviation Fuel Sample Containers forTests Affected by Trace ContaminationE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practic
9、e for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ISO Standards:3ISO 3274 Geometrical Product Specifications (GPS)Surface Texture: Profile MethodNominal Characteris-tics Of Contact (Stylus) InstrumentsISO 4288 Geometrical Product Specifications (GPS)Surface Text
10、ure: Profile MethodRules And ProceduresFor The Assessment Of Surface Texture2.3 ASTM Adjuncts:4Color Standard for Tube Deposit Rating3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 deposits, noxidative products laid down on the testarea of the heater tube or caught in the test
11、 filter, or both.3.1.1.1 DiscussionFuel deposits will tend to predominateat the hottest portion of the heater tube, which is between the30-mm and 50-mm position.3.1.2 heater tube, nan aluminum coupon controlled atelevated temperature, over which the test fuel is pumped.3.1.2.1 DiscussionThe tube is
12、resistively heated and con-trolled in temperature by a thermocouple positioned inside.The critical test area is the thinner portion, 60 mm in length,1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility o
13、fSubcommittee D02.J0.03 on Combustion and Thermal Properties.Current edition approved Oct. 1, 2014. Published December 2014. Originallyapproved in 1973. Last previous edition approved in 2014 as D3241 14. DOI:10.1520/D3241-14A.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orc
14、ontact 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 Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland,
15、http:/www.iso.org.4Available from ASTM International Headquarters. Order Adjunct No.ADJD3241. Original adjunct produced in 1986.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United
16、States1between the shoulders of the tube. Fuel inlet to the tube is at the0-mm position, and fuel exit is at 60 mm.3.2 Abbreviations:3.2.1 Pdifferential pressure.4. Summary of Test Method4.1 This test method for measuring the high temperaturestability of gas turbine fuels uses an instrument that sub
17、jectsthe test fuel to conditions that can be related to those occurringin gas turbine engine fuel systems. The fuel is pumped at afixed volumetric flow rate through a heater, after which itenters a precision stainless steel filter where fuel degradationproducts may become trapped.4.1.1 The apparatus
18、 uses 450 mL of test fuel ideally duringa 2.5-h test. The essential data derived are the amount ofdeposits on an aluminum heater tube, and the rate of pluggingof a 17 m nominal porosity precision filter located justdownstream of the heater tube.5. Significance and Use5.1 The test results are indicat
19、ive of fuel performanceduring gas turbine operation and can be used to assess the levelof deposits that form when liquid fuel contacts a heated surfacethat is at a specified temperature.6. Apparatus6.1 Aviation Fuel Thermal Oxidation Stability Tester5Eight models of suitable equipment may be used as
20、 indicatedin Table 1.6.1.1 Portions of this test may be automated. Refer to theappropriate user manual for the instrument model to be usedfor a description of detailed procedure. A manual is providedwith each test rig. (WarningNo attempt should be made tooperate the instrument without first becoming
21、 acquainted withall components and the function of each.)6.1.2 Certain operational parameters used with the instru-ment are critically important to achieve consistent and correctresults. These are listed in Table 2.6.2 Heater Tube Deposit Rating Apparatus:6.2.1 Visual Tube Rater (VTR), the tuberator
22、 described inAnnex A1.6.2.2 Interferometric Tube Rater (ITR)the tuberator de-scribed in Annex A2.6.2.3 Ellipsometric Tube Rater (ETR)the tuberator de-scribed in Annex A3.6.3 Because jet fuel thermal oxidation stability is definedonly in terms of this test method, which depends upon, and isinseparabl
23、e from, the specific equipment used, the test methodshall be conducted with the equipment used to develop the testmethod or equivalent equipment.7. Reagents and Materials7.1 Use distilled (preferred) or deionized water in the spentsample reservoir as required for Model 230 and 240 instru-ments.7.2 U
24、se methyl pentane, 2,2,4-trimethylpentane, orn-heptane (technical grade, 95 mol % minimum purity) asgeneral cleaning solvent. This solvent will effectively cleaninternal metal surfaces of apparatus before a test, especiallythose surfaces (before the test section) that contact freshsample. (Warning E
25、xtremely flammable. Harmful if inhaled(see Annex A5).)7.2.1 Use trisolvent (equal mix of acetone (1), toluene (2),and isopropanol (3) as a specific solvent to clean internal(working) surface of test section only. (Warning(1) Ex-tremely flammable, vapors may cause flash fire; (2) and (3)Flammable. Va
26、pors of all three harmful. Irritating to skin, eyes,and mucous membranes.)7.3 Use dry calcium sulfate + cobalt chloride granules (97 +3 mix) in the aeration dryer. This granular material changesgradually from blue to pink color indicating absorption ofwater. (WarningDo not inhale dust or ingest. May
27、 causestomach disorder.)8. Standard Operating Conditions8.1 Standard conditions of the test method are as follows:5The following equipment, as described in Table 1 and RR:D02-1309, was usedto develop this test method. The following equipment, as described in Table 1 anddetermined as equivalent in te
28、sting as detailed in RR:D02-1631, is provided by PAC,8824 Fallbrook Drive, Houston, TX 77064. The following equipment, as describedin Table 1 and determined as equivalent in testing as detailed in RR:D02-1728, isprovided by Falex Corporation, 1020 Airpark Dr., Sugar Grove, IL, 60554-9585.This is not
29、 an endorsement or certification by ASTM International.TABLE 1 Instrument ModelsInstrument Model Pressurize With Principle Differential Pressure by202Anitrogen gear Hg Manometer; No Record203Anitrogen gear Manometer + Graphical Record215Anitrogen gear Transducer + Printed Record230Ahydraulic syringe
30、 Transducer + Printout240Ahydraulic syringe Transducer + Printout230 Mk IIIBhydraulic dual piston (HPLC Type) Transducer + PrintoutF400Chydraulic dual piston (HPLC Type) Transducer + Printout230 Mk IVDhydraulic single piston (HPLC Type) Transducer + PrintoutASee RR:D02-1309.BSee RR:D02-1631.CSee RR:
31、D02-1728.DSee RR:D02-1757.D3241 14a28.1.1 Fuel Quantity, 450-mL minimum for test + about 50mL for system.8.1.2 Fuel Pre-TreatmentFiltration through a single layerof general purpose, retentive, qualitative filter paper followedby a 6-min aeration at 1.5 L/min air flow rate for a maximumof 1000 mL sam
32、ple using a coarse 12-mm borosilicate glassgas dispersion tube.8.1.3 Fuel System Pressure, 3.45 MPa (500 psi) 610 %gauge.8.1.4 Thermocouple Position, at 39 mm.8.1.5 Fuel System Prefilter Element, filter paper of 0.45-mpore size.8.1.6 Heater Tube Control Temperature, preset as specifiedin applicable
33、specification.8.1.7 Fuel Flow Rate, 3.0 mL/min 6 10 %.8.1.8 Minimum Fuel Pumped During Test, 405 mL.8.1.9 Test Duration, 150 6 2 min.8.1.10 Cooling Fluid Flow, approximately 39 L/h, or centerof green range on cooling fluid meter.TABLE 2 Critical Operating Characteristics of D3241 InstrumentsItem Def
34、initionTest apparatus Tube-in-shell heat exchanger as illustrated in Fig. 1.Test coupons:Heater tubeA, B, CSpecially fabricated aluminum tube that produces controlledheated test surface; new one for each test. An electronic recordingdevice, such as a radio-frequency identification device (RFID),may
35、be embedded into the heater tube rivet located at the bottomof the heater tube.Tube identification Each heater tube may be physically identified with a unique serialnumber, identifying the manufacturer and providing traceability tothe original material batch. This data may be stored on an elec-troni
36、c recording device, such as a RFID, embedded into the heatertube.Tube metallurgy 6061-T6 Aluminum, plus the following criteriaa) The Mg:Si ratio shall not exceed 1.9:1b) The Mg2Si percentage shall not exceed1.85 %Tube dimensions: Dimension ToleranceTube length, mm 161.925 0.254Center section length,
37、 mm 60.325 0.051Outside diameters, mmShoulders 4.724 0.025Center section 3.175 0.051Inside diameter, mm 1.651 0.051Total indicator runout, mm, max 0.013Mechanical surface finish, nm, in accordance with ISO 3274and ISO 4288 using the mean of four 1.25measurements5020Test filter5nominal 17-m stainless
38、 steel mesh filter element to trap deposits;new one for each testInstrument parameters:Sample volume 600 mL of sample is aerated, then this aerated fuel is used to fillthe reservoir leaving space for the piston; 450 45 mL may bepumped in a valid testAeration rate 1.5 L/min dry air through spargerFlo
39、w during test 3.0 10 % mL/min (2.7 min to 3.3 max)Pump mechanism positive displacement, gear or piston syringeCooling bus bars fluid cooled to maintain consistent tube temperature pro-fileThermocouple (TC) Type J, fiber braid or Iconel sheathed, or Type K, Iconel sheathedOperating pressure:System 3.
40、45 MPa 10 % on sample by pressurized inert gas (nitrogen) orby hydraulically transmitted force against control valve outlet re-strictionAt test filter differential pressure (P) measured across test filter (by mercurymanometer or by electronic transducer) in mm HgOperating temperature:For test as sta
41、ted in specification for fuelUniformity of run maximum deviation of 2C from specified temperatureCalibration pure tin at 232C (and for Models 230 and 240 only, pure lead at327C for high point and ice + water for low point reference)AThe following equipment, heater tubes, manufactured by PAC, 8824 Fa
42、llbrook Drive, Houston, TX 77064, was used in the development of this test method. This is notan endorsement or certification by ASTM International.BAtest protocol to establish equivalence of heater tubes is on file atASTM International Headquarters and may be obtained by requesting Research Report
43、RR:D02-1550.CThe following equipment, heater tube and filter kits, manufactured by Falex Corporation, 1020Airpark Dr., Sugar Grove, IL, 60554-9585, was run through the test protocolin RR:D02-1550 and determined as equivalent to the equipment used to develop the test method. This test is detailed in
44、RR:D02-1714. This is not an endorsement orcertification by ASTM International.D3241 14a38.1.11 Power Setting, approximately 75 to 100 on non-computer models; internally set for computer models.9. Preparation of Apparatus9.1 Cleaning and Assembly of Heater Test Section:9.1.1 Clean the inside surface
45、of the heater test section usinga nylon brush saturated with trisolvent material to remove alldeposits.9.1.2 Check the heater tube to be used in the test for surfacedefects and straightness by referring to the procedure inAnnexA1.10. Be careful, also, to avoid scratching tube shoulderduring the exam
46、ination, since the tube shoulder must besmooth to ensure a seal under the flow conditions of the test.9.1.3 Assemble the heater section using new items: (1)visually checked heater tube, (2) test filter, and (3) threeO-rings. Inspect insulators to be sure they are undamaged.NOTE 1Heater tubes must no
47、t be reused. Tests indicate that magne-sium migrates to the heater tube surface under normal test conditions.Surface magnesium may reduce adhesion of deposits to reused heatertube.9.1.4 During assembly of heater section, handle tube care-fully so as not to touch center part of tube. IF CENTER OFHEAT
48、ER TUBE IS TOUCHED, REJECT THE TUBE SINCETHE CONTAMINATED SURFACE MAY AFFECT THEDEPOSIT-FORMING CHARACTERISTICS OF THE TUBE.9.2 Cleaning and Assembly of Remainder of Test Compo-nents:9.2.1 Perform the following steps in the order shown priorto running a subsequent test.NOTE 2It is assumed that the a
49、pparatus has been disassembled fromprevious test (see Annex A4 or appropriate user manual for assembly/disassembly details).9.2.2 Inspect and clean components that contact test sampleand replace any seals that are faulty or suspect especially the(1) lip seal on piston, and (2) O-rings on the reservoir cover,lines, and prefilter cover.9.2.3 Install prepared heater section (as described in 9.1.1 9.1.4).9.2.4 Assemble pre-filter with new element and install.9.2.5 Check thermocouple for correct reference position,then lower into standar