1、Designation: D3241 11aDesignation 323/99An American National StandardStandard 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, in
2、 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 Department of Defense.1. Scope*1.1 T
3、his 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 values stated in SI units are to be regarded asstandard. No ot
4、her units of measurement are included in thisstandard.1.4 WARNINGMercury 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
5、 taken when handling mercury andmercury containing products. See the applicable 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 s
6、tate or countrymay be prohibited by law.1.5 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
7、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:2D1655 Specification for Aviation Turbine FuelsD4306 Practice for Aviation Fuel Sample Containers forTests Affected by Trace ContaminationE177 Practice
8、for Use of the Terms Precision and Bias inASTM Test MethodsE691 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 Characteris-tics Of Contact (Stylus) I
9、nstrumentsISO 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 Standard:3.1.1 depositsoxidative product
10、s 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 controlled at el-evated temperature
11、, 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 the tube is at the0-mm position, an
12、d 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 an instrument that subjects1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Product
13、s and Lubricants and is the direct responsibility of SubcommitteeD02.J0.03 on Combustion and Thermal Properties.Current edition approved Oct. 1, 2011. Published October 2011. Originallyapproved in 1973. Last previous edition approved in 2011 as D324111. DOI:10.1520/D3241-11A.2For referenced ASTM sta
14、ndards, 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 (ISO), 1, ch. dela Voi
15、e-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.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 Barr Harbor Drive, PO
16、Box C700, West Conshohocken, PA 19428-2959, United States.the 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 degra
17、dationproducts may become trapped.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 filter located justdownstream of the heater tube.5.
18、 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. Apparatus6.1 Aviation Fuel Thermal Oxidation Stability Tes
19、ter5Sixmodels 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 instrument model to be usedfor a description of detailed procedure. A manual is providedwith each test rig. (WarningNo attempt should be ma
20、de tooperate the instrument without first becoming 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 Appa
21、ratus: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 isinseparable from, the specific equipment used, the test methodshall be conducted with the equipment used to develo
22、p 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 Use methyl pentane, 2,2,4-trimethylpentane, orn-heptane (technical grade, 95 mol % minimum purity) asgene
23、ral cleaning solvent. This solvent will effectively cleaninternal metal surfaces of apparatus before a test, especiallythose surfaces (before the test section) that contact freshsample. (WarningExtremely flammable. Harmful if inhaled(see Annex A3).)7.2.1 Use trisolvent (equal mix of acetone (1), tol
24、uene (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. Vapors of all three harmful. Irritating to skin, eyes,and mucous membranes.)7.3 Use dry calcium sulfate + c
25、obalt 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 causestomach disorder.)8. Standard Operating Conditions8.1 Standard conditions of the test method are as
26、 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 followedby a 6-min aeration at 1.5 L/min air flow rate for a maximumof 1000 mL sample using a coarse 12-mm bo
27、rosilicate 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 size.8.1.6 Heater Tube Control Temperature, preset as specifiedin applicable specification.8.1.7 Fuel Flow
28、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.8.1.11 Power Setting, approximately 75 to 100 on non-computer models; internally set for computer mod
29、els.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 testing as detailed in RR:D02-1631, is provided byPAC, 8824 Fallbrook Drive, Houston, TX 77064. The following eq
30、uipment, asdescribed in Table 1 and determined as equivalent in testing as detailed inRR:D02-1728, is provided by Falex Corporation, 1020 Airpark Dr., Sugar Grove,IL, 60554-9585. This is not an endorsement or certification by ASTM International.TABLE 1 Instrument ModelsInstrument Model Pressurize Wi
31、th Principle Differential Pressure by202Anitrogen gear Hg Manometer; No Record203Anitrogen gear Manometer + Graphical Record215Anitrogen gear Transducer + Printed Record230Ahydraulic syringe Transducer + Printout240Ahydraulic syringe Transducer + Printout230 Mk IIIBhydraulic dual piston (HPLC Type)
32、Transducer + PrintoutF400Chydraulic dual piston (HPLC Type) Transducer + PrintoutASee RR:D02-1309.BSee RR:D02-1631.CSee RR:D02-1728.D3241 11a29. 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 satur
33、ated 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 in AnnexA1.10. Be careful, also, to avoid scratching tube shoulderduring the examination, since the tube shoulder must besmooth to
34、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.TABLE 2 Critical Operating Characteristics of D3241 InstrumentsItem Definiti
35、onTest apparatus Tube-in-shell heat exchanger as illustrated in Fig. 1.Test couponsHeater tubeA,B,CSpecially fabricated aluminum tube that produces controlled heated testsurface; new one for each testTube identification Each heater tube may be physically identified with a unique serialnumber, identi
36、fying 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, mm 161.925 60.254Center s
37、ection 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 1.25mmmeasurements50 6 20Test filter5nomin
38、al 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 rate 1.5 L/min dry air
39、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, Iconel sheathedOperating
40、 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) in mm HgOperating tempera
41、tureFor 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, heater tubes, manufact
42、ured by PAC, 8824 Fallbrook Drive, Houston, TX 77064, was used in the development of this test method. This isnot an endorsement or certification by ASTM International.BA test protocol to establish equivalence of heater tubes is on file at ASTM International Headquarters and may be obtained by reque
43、sting Research ReportRR:D02-1550.CThe following equipment, heater tube and filter kits, manufactured by Falex Corporation, 1020 Airpark Dr., Sugar Grove, IL, 60554-9585, was run through the testprotocol in RR:D02-1550 and determined as equivalent to the equipment used to develop the test method. Thi
44、s test is detailed in RR:D02-1714. This is notanendorsement or certification by ASTM International.FIG. 1 Standard Heater Section, Essential to All D3241 TestInstrumentsD3241 11a3NOTE 1Heater tubes must not be reused. Tests indicate that magne-sium migrates to the heater tube surface under normal te
45、st 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 OFHEATER TUBE IS TOUCHED, REJECT THE TUBE SINCETHE CONTAMINATED SURFACE MAY AFFECT THEDEPOSIT-FORMING
46、 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 apparatus has been disassembled fromprevious test (see Annex A2 or appropriate user manual for a
47、ssembly/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.
48、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 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
49、components 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 yearor 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 1
