1、Designation: D 3241 08aDesignation 323/99An American National StandardStandard Test Method forThermal Oxidation Stability of Aviation Turbine Fuels(JFTOT Procedure)1This standard is issued under the fixed designation D 3241; the number immediately following the designation indicates the year oforigi
2、nal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of De
3、fense.1. Scope*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 values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly. The differentia
4、l pressure values in mm Hg are definedonly in terms of this test method.1.3 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 t
5、he applica-bility of regulatory limitations prior to use. For specificwarning statements, see 6.1.1, 7.2, 7.2.1, 7.3, 11.1.1, andAnnex A3.2. Referenced Documents2.1 ASTM Standards:2D 1655 Specification for Aviation Turbine FuelsD 4306 Practice for Aviation Fuel Sample Containers forTests Affected by
6、 Trace ContaminationE 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 691 Practice 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 Ch
7、aracteris-tics Of Contact (Stylus) InstrumentsISO 4288 Geometrical Product Specifications (GPS)Surface Texture: 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 Stan
8、dard:3.1.1 depositsoxidative products laid down on the testarea of the heater tube or caught in the test 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 tubean aluminum coupon
9、 controlled at el-evated temperature, over which the test fuel is pumped.3.1.2.1 DiscussionThe tube is resistively heated and con-trolled in temperature by a thermocouple positioned inside.The critical test area is the thinner portion, 60 mm in length,between the shoulders of the tube. Fuel inlet to
10、 the tube is at the0-mm position, and fuel exit is at 60 mm.3.2 Abbreviations:3.2.1 DPdifferential pressure.4. Summary of Test Method4.1 This test method for measuring the high temperaturestability of gas turbine fuels uses the Jet Fuel ThermalOxidation Tester (JFTOT) that subjects the test fuel to
11、condi-tions that can be related to those occurring in gas turbineengine fuel systems. The fuel is pumped at a fixed volumetricflow rate through a heater, after which it enters a precisionstainless steel filter where fuel degradation products maybecome trapped.1This test method is under the jurisdict
12、ion of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.J0.03 on Combustion and Thermal Properties.Current edition approved March 1, 2008. Published April 2008. Originallyapproved in 1973. Last previous edition approved in 2008 as D 324108.2F
13、or 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 International Organization for Standardization
14、(ISO), 1 rue deVaremb, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.4Available from ASTM International Headquarters. Order Adjunct No.ADJD3241. Original adjunct produced in 1986.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100
15、 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.1.1 The apparatus 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 filt
16、er located justdownstream of the heater tube.5. Significance and Use5.1 The test results are indicative 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.
17、1 Jet Fuel Thermal Oxidation Tester5(JFTOT)Fivemodels of suitable equipment may be used as indicated inTable 1.6.1.1 Portions of this test may be automated. Refer to theappropriate user manual for the model JFTOT to be used for adescription of detailed procedure. A manual is provided witheach test r
18、ig, and the latest version of each manual is on file atASTM as a Research Report.5(WarningNo attempt shouldbe made to operate the JFTOT without first becoming ac-quainted with all components and the function of each.)6.1.2 Certain operational parameters used with the JFTOTinstrument are critically i
19、mportant to achieve consistent andcorrect results. These are listed in Table 2.6.2 Heater Tube Deposit Rating Apparatus:6.2.1 Visual Tube Rater, the tuberator described in AnnexA1.6.3 Because jet fuel thermal oxidation stability is definedonly in terms of this test method, which depends upon, and is
20、inseparable 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 JFTOTs.7
21、.2 Use 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. (Warni
22、ngExtremely flammable. Harmful if inhaled(see Annex A3).)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.
23、 Vapors 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.
24、May causestomach disorder.)8. Standard Operating Conditions8.1 Standard conditions of the test method are as follows:8.1.1 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 f
25、ollowedby a 6-min aeration at 1.5 L/min air flow rate for a maximumof 1000 mL sample 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,at39mm.8.1.5 Fuel System Prefilter Element, filter paper of 0.45-mpore
26、 size.8.1.6 Heater Tube Control Temperature, preset as specifiedin applicable 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
27、 meter.8.1.11 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 of the heater test section usinga nylon brush saturated with trisolvent material
28、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 in AnnexA1.10. Be careful, also, to avoid scratching tube shoulderduring the examination, since the tube shoulder must besmooth to ensure a seal under the flow c
29、onditions 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.5The following equipment (JFTOT) as described in Table 1 and RR: D021395,RR: D021396, and RR: D021397, was
30、 used to develop this test method, asprovided by Alcor Petroleum Instruments, 919 Isom, San Antonio, TX 78216. Thisis not an endorsement or certification by ASTM International.TABLE 1 Models of JFTOTJFTOTModelUserManualPressurizeWithPumpPrincipleDifferential Pressure By202 202/203Anitrogen gear Hg M
31、anometer; No Record203 202/203Anitrogen gear Manometer + GraphicalRecord215 215Bnitrogen gear Transducer + PrintedRecord230 230/240Chydraulic syringe Transducer + Printout240 230/240Chydraulic syringe Transducer + Printout230 Mk III 230 Mk IIIDhydraulic dual piston(HPLCType)Transducer + PrintoutAAva
32、ilable from ASTM International Headquarters. Request RR:D021395.BAvailable from ASTM International Headquarters. Request RR:D021396.CAvailable from ASTM International Headquarters. Request RR:D021397.DAvailable from ASTM International Headquarters. Request RR:D021631.D 3241 08a2NOTE 1Heater tubes mu
33、st not 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 O
34、FHEATER 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
35、the apparatus has been disassembled fromprevious test (see Annex A2 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 theTABLE 2 Critical Operating Characteristics of JFT
36、OT InstrumentsItem DefinitionTest apparatus tube-in-shell heat exchanger as illustrated in Fig. 1.Test couponsHeater tubeA,Bspecially fabricated aluminum tube that produces controlled heated testsurface; new one for each testTube identification Each JFTOT tube may be physically identified with a uni
37、que serialnumber, identifying the manufacturer and providing traceability to theoriginal material batchTube 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, m
38、m 161.925 60.254Center section length,mm60.325 60.051Outside diameters, mmShoulders 4.724 60.025Center section 3.175 60.051Inside diameter, mm 1.651 60.051Total indicator runout,mm, max0.013Mechanical surface finish, nm, inaccordance with ISO 3274and ISO 4288 using the mean offour 1.25mmmeasurements
39、50 6 20Test filter5nominal 17-m stainless steel mesh filter element to trap deposits; newone for each testInstrument parametersSample volume 600 mL of sample is aerated, then this aerated fuel is used to fill thereservoir leaving space for the piston; 450 6 45 mL may be pumped in avalid testAeration
40、 rate 1.5 L/min dry air through spargerFlow during test 3.0 6 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 profileThermocouple (TC) Type J, fiber braid or Iconel sheathed, or Type K,
41、Iconel sheathedOperating pressureSystem 3.45 MPa 6 10 % on sample by pressurized inert gas (nitrogen) or byhydraulically transmitted force against control valve outlet restrictionAt test filter differential pressure (DP) measured across test filter (by mercurymanometer or by electronic transducer) i
42、n mm HgOperating temperatureFor test as stated in specification for fuelUniformity of run maximum deviation of 62C from specified temperatureCalibration pure tin at 232C (and for Models 230 and 240 only, pure lead at 327Cfor high point and ice + water for low point reference)AThe following equipment
43、, heater tubes, manufactured by Alcor Petroleum Instruments, 919 Isom, San Antonio, TX 78216, was used in the development of this testmethod. This is not an endorsement or certification by ASTM International.BA test protocol to establish equivalence of heater tubes is on file at ASTM International H
44、eadquarters and may be obtained by requesting Research Report RR:D021550.FIG. 1 Standard Heater Section, Essential to All JFTOTInstrumentsD 3241 08a3(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-
45、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 standard operating position.9.2.6 On Models 230 and 240, make sure the water beakeris empty.10. Calibration and Standardization Procedure10.1 Perform checks of key co
46、mponents at the frequencyindicated in the following (see Annexes or user manual fordetails).10.1.1 ThermocoupleCalibrate a thermocouple when firstinstalled and then normally every 30 to 50 tests thereafter, butat least every 6 months (see A2.2.8).10.1.2 Differential Pressure CellStandardize once a y
47、earor when installing a new cell (see A2.2.6).10.1.3 Aeration DryerCheck at least monthly and changeif color indicates significant absorption of water (see 7.3).10.1.4 Metering PumpPerform two checks of flow ratefor each test as described in Section 11.10.1.5 Filter Bypass ValveFor Models 202, 203,
48、and 215,check for leakage at least once a year (see X1.6).11. Procedure11.1 Preparation of Fuel Test Sample:11.1.1 Filter and aerate sample using standard operatingconditions (see A2.2.9). (WarningAll jet fuels must beconsidered flammable except JP5 and JP7. Vapors are harmful(see A3.3, A3.6, and A3
49、.7).)NOTE 3Before operating, see Warning in 6.1.1.NOTE 4Test method results are known to be sensitive to tracecontamination from sampling containers. For recommended containers,refer to Practice D 4306.11.1.2 Maintain temperature of sample between 15C and32C during aeration. Put reservoir containing sample into hotor cold water bath to change temperature, if necessary.11.1.3 Allow no more than1htoelapse between the end ofaeration and the start of the heating of the sample.11.2 Final Assembly:11.2.1 Assemble the reservoir section (see User
