1、Designation: D3948 11An American National StandardStandard Test Method forDetermining Water Separation Characteristics of AviationTurbine Fuels by Portable Separometer1This standard is issued under the fixed designation D3948; the number immediately following the designation indicates the year ofori
2、ginal 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.This standard has been approved for use by agencies of the Department of D
3、efense.1. Scope*1.1 This test method covers a rapid portable means for fieldand laboratory use to rate the ability of aviation turbine fuels torelease entrained or emulsified water when passed throughfiberglass coalescing material.1.2 The procedure section of this test method contains twodifferent m
4、odes of test equipment operation. The primarydifference between the modes of operation is the rate of fuelflow through the fiberglass coalescing material. Test methodselection is dependent on the particular fuel to be tested.1.3 The values stated in SI units are to be regarded as thestandard. The va
5、lues given in parentheses are for informationonly.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 r
6、egulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1655 Specification for Aviation Turbine FuelsD2550 Method of Test for Water Separation Characteristicsof Aviation Turbine Fuels3D3602 Test Method for Water Separation Characteristics ofAviation Turbine Fuels3D4306 Practic
7、e for Aviation Fuel Sample Containers forTests Affected by Trace Contamination2.2 Military Standards:4MIL-T-5624 Turbine Fuel, Aviation Grades JP-4, JP-5, andJP-5/JP-8 STMIL-T-38219 Turbine Fuel, Low Volatility, JP-7MIL-T-83133 Turbine Fuel, Aviation, Kerosene Types,NATO F34 (JP-8), NATO F-35, and J
8、P-8+1003. Terminology3.1 Definitions:3.1.1 Micro-Separometer rating (MSEP rating), nin theaviation fuel industry, a numerical value indicating the ease ofseparating emulsified water from aviation (jet) fuel by coales-cence as affected by the presence of surface active materials(also known as surface
9、 active agents or surfactants).3.1.1.1 DiscussionMSEP ratings obtained using Test Aand Test B are termed MSEP-A and MSEP-B, respectively.3.1.1.2 DiscussionMSEP ratings are only valid within therange of 50 to 100, with ratings at the upper end of the rangeindicating a clean fuel with little or no con
10、tamination bysurfactants, which is expected to show good water-separatingproperties when passed through a filter-separator (coalescing-type filter) in actual service.3.1.2 reference fluid, nin MSEP and DSEP diesel sepa-rability water separability tests, a reference fluid base towhich a prescribed qu
11、antity of a known surface active agenthas been added.3.1.2.1 DiscussionThe known surface active agent istypically bis-2-ethylhexyl sodium sulfosuccinate, commonlyreferred to as AOT, dissolved in toluene.3.1.3 surfactant, nin petroleum fuels, surface active ma-terial (or surface active agent) that co
12、uld disarm (deactivate)filter separator (coalescing) elements so that free water is notremoved from the fuel in actual service.3.1.3.1 DiscussionTechnically, surfactants affect the in-terfacial tension between water and fuel which affects thetendency of water to coalesce into droplets.3.2 Definition
13、s of Terms Specific to This Standard:1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.J0.05 on Fuel Cleanliness.Current edition approved Oct. 1, 2011. Published November 2011. Originallyapproved
14、in 1980. Last previous edition approved in 2008 as D394808. DOI:10.1520/D3948-11.2For 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
15、 onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.1*A Summary of Changes section appears at the end of t
16、his standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.1 reference fluid base, nin aviation MSEP waterseparability tests, jet fuel that has been cleaned in a prescribedmanner to remove all surface-active contaminants (agents
17、), andhaving a minimum MSEP rating of 97.4. Summary of Test Method4.1 A water/fuel sample emulsion is created in a syringeusing a high-speed mixer. The emulsion is then expelled fromthe syringe at a programmed rate through a standard fiberglasscoalescer and the effluent is analyzed for uncoalesced w
18、ater bya light transmission measurement. The results are reported ona 0-to-100 scale to the nearest whole number. High ratingsindicate the water is easily coalesced, implying that the fuel isrelatively free of surfactant materials. A test can be performedin 5 to 10 min.5. Significance and Use5.1 Thi
19、s test method provides a measure of the presence ofsurfactants in aviation turbine fuels. Like Test Methods D2550and D3602, this test method can detect carryover traces ofrefinery treating residues in fuel as produced. They can alsodetect surface active substances added to or picked up by thefuel du
20、ring handling from point of production to point of use.Certain additives can also have an adverse effect on the rating.Some of these substances affect the ability of filter separatorsto separate free water from the fuel.5.2 The Micro-Separometer has a measurement range from50 to 100. Values obtained
21、 outside of those limits are undefinedand invalid. In the event a value greater than 100 is obtained,there is a good probability that light transmittance was reducedby material contained in the fuel used to set the 100 referencelevel. The material was subsequently removed during thecoalescing portio
22、n of the test, thus, the processed fuel had ahigher light transmittance than the fuel sample used to obtainthe 100 reference level resulting in the final rating measuring inexcess of 100.5.3 Test Mode A function of the separometer will giveapproximately the same rating for Jet A, Jet A-1, MIL JP-5,M
23、IL JP-7, and MIL JP-8 fuels as Test Methods D2550 andD3602. Using Mode A water separation characteristic ratingsof Jet B and MIL JP-4 fuels will not necessarily be equivalentto Test Method D2550 but will give approximately the samerating as Test Method D3602. All Micro-Separometers haveTest Mode A c
24、apability.5.4 The Test Mode B option is used to determine waterseparation ratings for MIL JP-4 fuels containing fuel systemcorrosion and icing inhibitors. These ratings are approximatelythe same as those obtained using Test Method D2550.5.5 Selection of Mode A or Mode B depends on the specificfuel a
25、nd specification requirement. Table 1 identifies therecommended test method for various fuels.5.6 The basic difference between ModesAand B is the flowrate at which the water/fuel emulsion is forced through thestandard fiberglass coalescer cell. The lapsed time required toforce the emulsion through t
26、he coalescer cell in Mode A is 456 2 s, whereas, Mode B requires 25 6 1s.6. Apparatus6.1 A Micro-Separometer5,6is used to perform the test. Theunit is completely portable and self-contained, capable ofoperating on an internal rechargeable battery pack or beingconnected to an ac power source using po
27、wer cords which areavailable for various voltages. Connection to an ac powersource will provide power to the unit and affect batteryrecharge. The accessories as well as the expendable materialsfor six tests can be packed in the cover of the lockable case.NOTE 1An extensive study was performed to ver
28、ify that the Mark XMicro-Separometer gives equivalent results to the Mark V DeluxeMicro-Separometer. See Research Report RR:D02-1647.7NOTE 2The Mark X has a universal power supply and requires onlyone power cord as compared to the Mark V Deluxe that requires individualpower cords for different volta
29、ges.6.2 The Micro-Separometer Mark V Deluxe and Mark Xand associated control panel are shown in Fig. 1 and Fig. 2,respectively. The emulsifier is on the right side of the raisedpanel and the syringe drive mechanism is on the left side. Thecontrol panel containing the operating controls is mounted on
30、the fixed panel in the left side of the case. Table 2 lists themanual and audio operating characteristics of the instruments.6.2.1 All of the controls are located in a pushbutton array onthe control panel. The pushbuttons illuminate when depressedthus indicating operational status. A circuit breaker
31、 located onthe control panel provides protection for the ac power circuit.6.2.2 The Mark X has an LCD display on the control panelthat provides information to the operator during the test. Theinformation includes test status and an error code that definesa malfunction in the Micro-Separometer.6.2.3
32、The turbidimeter is located under the main controlpanel and consists of a well in which the sample vial is placed,a light source, and a photocell.6.2.4 By depressing the ON pushbutton, the electroniccircuits are energized. The ON pushbutton pulses on and offwhen the instruments are being operated by
33、 an ac source andconstantly remains on when the battery (dc) pack is used. The5The sole source of supply of the apparatus, the Model 1140 Micro-SeparometerMark V Deluxe and Mark X, known to the committee at this time is EmceeElectronics, Inc., 520 CypressAve., Venice, FL 34285, www.emcee-. If you ar
34、e aware of alternative suppliers, please provide this information to ASTMInternational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.6The Model 1140 Micro-Separometers Mark III and Mark V Standard versionsmay a
35、lso be used, but they are no longer supported by the manufacturer. Foroperating procedures using these instruments, the user is referred to D394887.7Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1647.TABLE 1 Applicable Test
36、 Mode for Various FuelsAvailable Test Mode(s)Fuel Applicable Test ModeJet A AJet A-1 AJet B AMIL JP-5 AMIL JP-7 AMIL JP-8 AMIL JP-4 BD3948 112lettered pushbuttons will sequentially illuminate on and offindicating READY operational status.NOTE 3Of the lettered (A-G) pushbuttons on the control panel o
37、f theMark V Deluxe, only the A and B pushbuttons are applicable to this testmethod. Of the lettered (Jet A Diesel) pushbuttons on the control panelof the Mark X, only the Jet A and Jet B pushbuttons are applicable to thistest method.6.2.5 The RESET pushbutton can be depressed at any timeto cancel th
38、e test in progress and restore the program to theinitial start mode. The lettered pushbuttons commence tosequentially illuminate, thus indicating a READY operationalstatus enabling test mode selection.6.2.6 Mark V Operation:6.2.6.1 Selection of Test Mode A or Test Mode B programsis accomplished by d
39、epressing either the A or B letteredpushbutton. The depressed pushbutton illuminates and thesequential illumination of the other lettered pushbuttonsceases. The START pushbutton also illuminates.6.2.6.2 The START pushbutton, when depressed initially,initiates the CLEAN cycle causing the syringe driv
40、e mecha-nism to travel to the UP position and the emulsifier motor tooperate for the cleaning operation.6.2.6.3 The START pushbutton, when depressed after theCLEAN cycle, initiates the automatic program sequence caus-ing the read indicator and the two ARROWED pushbuttons toilluminate, indicating tha
41、t a full-scale adjustment period is ineffect. A numerical value also appears on the meter.6.2.6.4 By depressing the appropriate ARROWED pushbut-ton, the displayed value on the meter can be increased ordecreased, as required, to attain the 100 reference level for thevial of fuel sample in the turbidi
42、meter.6.2.7 Mark X Operation:6.2.7.1 Selection of Test ModeAor Test Mode B program isaccomplished by depressing either the Jet A or Jet B letteredpushbutton. The depressed pushbutton illuminates and thesequential illumination of the other lettered pushbuttonsceases. The CLEAN 1 pushbutton also illum
43、inates.6.2.7.2 The first and second clean cycles are initiated bydepressing the CLEAN 1 and CLEAN 2 pushbuttons. TheRUN pushbutton will illuminate at the end of the second cleancycle.6.2.7.3 The automatic portion of the test sequence is initi-ated by depressing the RUN pushbutton.6.2.7.4 The 100 ref
44、erence level for the vial of fuel in theturbidimeter is set automatically and does not require anyadjustment. If the turbidimeter could not auto adjust to 100, theerror alert indicator illuminates and an ERR-04 is displayed.6.3 Accessory equipment and expendable materials neededto perform the test a
45、re shown in Fig. 3 and consist of thefollowing:6.3.1 Syringe Plug, (A)A plastic plug used to stopper thesyringe during the CLEAN and EMULSION cycles.6.3.2 Syringe, (Barrel (B) and Plunger (C)A disposableplastic syringe.6.3.2.1 Use of syringes other than those demonstrated to befree of surfactant con
46、tamination in a precision program such asdescribed in Section 12 will render test results invalid.FIG. 1 Micro-Separometer Mark V Deluxe and Associated Control PanelFIG. 2 Micro-Separometer Mark X and Associated Control PanelD3948 1136.3.3 Vials,(D), 25-mm outside diameter vial premarked forproper a
47、lignment in the turbidimeter well.6.3.4 Alumicel,8Coalescer (E), is an expendable, precali-brated aluminum coalescer cell with a tapered end to fit thesyringe. The coalescer has three labels as follows: AlumicelD3948JET FUEL.6.3.5 Pipet, (G) with Plastic Tip (F)An automatic handpipet with a disposab
48、le plastic tip.Apipet is supplied with eachMicro-Separometer.6.3.6 Water Container (H)A clean container of distilledwater (supplied with each six pack).6.3.7 Beaker, Catch Pan, or Plastic ContainerSuppliedwith each Micro-Separometer may be used to receive the wastefuel during the coalescence period
49、of the test (not shown).6.4 A new syringe, pipet tip, test sample vials, syringe plug,Alumicel coalescer, and distilled water are used in each test.These expendable materials are available in a kit, termedMicro-Separometer Six Pack, containing supplies for six tests(Fig. 4).97. Reagents7.1 Aerosol OT, solid (100 % dry) bis-2-ethylhexyl sodiumsulfosuccinate.7.2 Toluene, ACS reagent grade. (WarningFlammable.Vapor harmful.).7.3 Dispersing AgentToluene solution (WarningFlammable. Vapor harmful.) containing 1 mg of Aerosol OTper millilitre of to
