1、Designation:D324005 Designation: D3240 11An American National StandardStandard Test Method forUndissolved Water In Aviation Turbine Fuels1This standard is issued under the fixed designation D3240; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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.Balloted and approved m
3、aterial has been included editorially, and the year date was changed on March 3, 2011.1. Scope*1.1 This test method covers the measurement of undissolved water in aviation turbine fuels in flowing fuel streams withoutexposing the fuel sample to the atmosphere or to a sample container. The usual rang
4、e of test readings covers from 1 to 60 ppmof free water. This test method does not detect water dissolved in the fuel, and thus test results for comparable fuel streams canvary with fuel temperature and the degree of water solubility in the fuel.1.2 This standard does not purport to address all of t
5、he safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1
6、free waterwater not dissolved in the fuel.3. Summary of Test Method3.1 A measured sample of fuel is passed through as uranine dye-treated filter pad. Undissolved (free) water in the fuel will reactwith the uranine dye. When the pad is subsequently illuminated by ultraviolet (UV) light, the dye previ
7、ously contacted by freewater will fluoresce a bright yellow with the brightness increasing for increasing amounts of free water in the fuel. The UVlight-illuminated pad is compared to a known standard using a photocell comparator, and the free water in the fuel sample is readout in parts per million
8、 by volume. By varying the fuel sample size, the range of the test method can be increased.4. Significance and Use4.1 Undissolved (free) water in aviation fuel can encourage the growth of microorganisms and subsequent corrosion in the tanksof aircraft and can also lead to icing of filters in the fue
9、l system. Control of free water is exercised in ground fueling equipmentby use of filter-coalescers and water separators.5. Apparatus5.1 Test Pad RaterTest Pad Rater (UV Source Device)A device2,3,4for comparing the fluorescence of the test pad to a knownstandard, while both are illuminated by the sa
10、me source of UV light, shall be used. The amount of UV light striking the standardshall be modulated until the total fluorescence of the test pad and the standard are equal; this shall be determined using a photocellbridge circuit null indicator. The light modulating device for controlling the UV li
11、ght striking the standard shall provide a directreading in parts per million by volume of free water.1This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.J0.05on Aviation Fuels.Fuel Cleanliness.Cur
12、rent edition approved Nov. 1, 2005.March 3, 2011. Published November 2005.March 2011. Originally approved in 1973. Last previous edition approved in 20012010as D324091(2001).D324010. DOI: 10.1520/D3240-05.10.1520/D3240-11.2TheAqua-Glo Series II instrument manufactured by Gammon Technical Products, I
13、nc., P.O. Box 400, Manasquan, NJ 08736-0400 was used in the precision test program.The unit is currently available in a Series V configuration, which is changed only in the power supply. All water content measuring components remain of the sameconfiguration as the Series II instrument. Manufacturers
14、 who wish to offer similar products are referred to Committee D02 Equipment Replacement Guidelines.3The sole source of supply of the apparatus known to the committee at this time is Gammon Technical Products Inc., P.O. Box 400, Manasquan, NJ 08736-0400.Ifyouare aware of alternative suppliers, please
15、 provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting ofthe responsible technical committee, which you may attend.3The sole source of supply of the apparatus known to the committee at this time is Gammon Technical Products Inc., P
16、.O. Box 400, Manasquan, NJ 08736-0400.4Aqua-Glo test pads were used in the Precision Test Program.4If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical
17、committee, which you may attend.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recomm
18、ends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C70
19、0, West Conshohocken, PA 19428-2959, United States.5.2 Test Pad Rater (LED Source Device)A device4,5for rating the fluorescence of the test pad directly by illumination by anarrow band light source provided by colored LEDs. The total fluorescence of the test pad is measured directly using a photosen
20、sitive transistor. The intensity of the fluorescence measurement is converted by the device and shall provide a direct readingin parts per million by volume of free water.5.3 Test PadsAbsorbent filter disks of 25-mm diameter shall be coated on one side with uranine (sodium fluorescein) dye ata conce
21、ntration of 0.23 to 0.29 mg per 25 mm pad. The test pads3,6shall be individually packaged in hermetically sealed envelopesor other suitable containers. Fresh, unused test pads shall have an orange color over the dyed surface. Any discoloration,unevenness in dye content, or faded (to a yellow color)
22、appearance shall be cause for rejection.5.35.4 Test Pad Holder3,7and Sampling LineA test pad holder and sampling line shall be used to draw the fuel sample throughthe test pad at a rate of 600 to 800 mL/min. Means shall be provided to flush the test pad sampling line and holder immediatelyprior to u
23、se. The test pad holder shall include an orifice of 1-mm (0.040-in.) diameter upstream of the pad to disperse water dropletsin the fuel.5.45.5 TweezersSuitable clean, dry tweezers shall be used at all times when handling the test pad.5.55.6 Blotting PaperClean, dry, absorbent paper towels, blotters,
24、 etc., shall be provided for blotting the test pad prior to ratingto remove excess fuel. The blotter paper shall neither impart color or stain nor leave any residue on the test pads.5.65.7 Sampling Valve Connection, designed to meet the following requirements: (1) It shall be mounted in the sampling
25、 point andmust incorporate a self-sealing quick action coupling designed to mate with a suitable connection leading to the selector valve ofthe sampling assembly. (2) It must be completely resistant to fuel and be leak proof up to the maximum working pressures to beencountered. (3) It must have a mi
26、nimum of internal recesses which could cause the holdup of contaminant. (4) It must be providedwith a dust cap.5.7Calibrating Standard, calibration of the instrument should be performed using a calibrating standard of known values.5.8 Calibrating Standard (UV Source Device)Field calibration of the i
27、nstrument should be performed using a calibratingstandard of known values.5.9 Calibrating Standard (LED Source Device)Factory calibration of the device shall be performed as prescribed in Section8.5.10 Field Verification (LED Source Device)If the operation of the instrument needs to be verified, an
28、unused pad may beinserted for reading; the value shall be less than 0.5 ppm. A reference target, available from the manufacturer, when inserted intothe device shall read within the limits printed on the rear of the reference target.6. Sampling6.1 The following procedure is applicable for dynamic lin
29、e samples only; that is, taking the fuel sample directly from the testsystem and through the test pad without exposing the sample to the atmosphere or to a sample container. The use of samplecontainers such as bottles or cans for the temporary storage of the sample will result in large errors and is
30、 not recommended.NOTE 1The amount of free water in a sample is very sensitive to the temperature of the sample. The use of sample containers such as bottles or canscan result in large errors due to changes in sample temperature, adsorption of water on container walls, etc.6.2 Attach the test pad hol
31、der assembly to the sampling port on the system.6.3 Flush the test pad holder assembly immediately prior to sampling, displacing the sampling line with at least two volumesof test fuel.6.4 Remove the sampling assembly, open the pad holder, and insert the new test pad using tweezers making sure that
32、the treatedside of the test pad is facing upstream. Installation of a three-way valve immediately upstream of the test pad holder will permitflushing with the test pad in place.NOTE 2Do not remove the test pad from the hermetically sealed package until ready for use. Do not allow any discrete water
33、droplets to come intocontact with the pad (from rain, sneezing, coughing, etc.). Exposure of the test pad to the atmosphere, especially on humid days, will also ruin the padin a matter of minutes.6.5 Pass 500 mL of fuel through the pad, accurately measuring the test sample quantity. Normal sample vo
34、lume is 500 mL oftest fuel, but if the reading is off scale (on high side), sample volumes down to 100 mL in volume may be used. In the latter case,a small graduated cylinder should be used to measure the sample volume.5A test pad holder was used in the Precision Test Program.5The sole source of sup
35、ply of the LED Source Device JF-WA1 instrument known to the committee at this time is manufactured by D-2 Incorporated, 19 Commerce ParkRoad, Pocasset, MA 02559. This instrument was used in a precision test program; reference Research Report RR:D02-1712.6Replacement calibrating standards, but only i
36、f the fluorescing standard for the instrument is returned for comparison rating.6Aqua-Glo test pads were used in the Precision Test Program.7Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D02-1195.7A test pad holder was used in
37、 the Precision Test Program.D3240 1126.6 Measure and record the temperature of the sample.7. Calibration Calibration (UV Source Device)7.1 The calibrating standard3 ,8corresponding to a given undissolved water content is placed in the test pad window. Turn onthe lamp and press the photocell comparat
38、or button. Zero the photocell comparator by adjusting the light modulating lever untilthere is a steady reading for 10 to 15 s. This may take a minute or longer. Always move the light modulating lever in the samedirection when zeroing the photocell comparator in calibration or testing to eliminate e
39、rrors caused by play in the lever. If thereading obtained does not agree with the calibration pad rating, adjust the photocell comparator by removing the plug screw onthe side of the photocell comparator at the 45 bend. Insert a small screwdriver, and adjust as necessary. Repeat the aboveprocedure u
40、ntil the rating obtained agrees with the calibration pad rating. The instrument should be calibrated prior to use eachday, after each hour of use, and when the ultraviolet light battery is replaced or recharged.8.Rating Procedure8.1Remove the test pad from the sampling holder using tweezers and pres
41、s between dry paper blotters or absorbent towels toremove excess fuel. To blot, press firmly (about 5 lb force) 3 or 4 times with heel of hand, moving the pad with tweezers eachtime.8.1.1For maximum accuracy the test pad should be read within 3 min after sampling is initiated. If the test pad is not
42、 readimmediately after sampling, it must be placed in a desiccator to prevent moisture pickup from the air. However, ratings made ondried test pads, that is, not damp with fuel, should be avoided if possible since they will give high and erroneous results.Conversely, rating a pad which has not been
43、well blotted will give a low reading as the excess fuel will absorb part of the UV lightand decrease fluorescence.8.2Using tweezers, put the pad into the pad rating device. Turn on the lamp and press the photocell button. Continuously zerothe photocell comparator by adjusting the light modulating le
44、ver until there is a steady reading for 10 to 15 s. Always move thelight modulating lever in the same direction when zeroing the photocell comparator to eliminate errors caused by backlash. Thismay take a minute or longer. Turn off the instrument light immediately after use to conserve battery power
45、.8.2.1The ultraviolet light must be on to get a reading. This can be checked by moving the light modulating lever from oneextreme to another. The photocell comparator meter needle should swing violently when this is done.8.3Record the instrument reading (estimated to the nearest tenth) and the sampl
46、e volume. Record the temperature of the fuel.8.4Visual observation of the used test pad is often of value. This is easily accomplished by removing the photocell comparatorassembly and viewing the test pad. Free water in fuel is normally well dispersed and will form an even distribution of many, smal
47、lpoints of yellow fluorescence on the test pad when illuminated by ultraviolet light. Large water drops, however, will form a few,large spots of yellow fluorescence on the pad. These large spots may give erroneous readings; the result should be disregarded anda new sample tested.8. Calibration (LED
48、Source Device)8.1 The unit maintains a stable factory calibration for period in excess of 1 year due to the stability of the LED source anddetector. Factory calibration should occur in accordance with the device manual, which is recommended on an annual basis.9. Rating Procedure (UV Source Device)9.
49、1 Remove the test pad from the sampling holder using tweezers and press between dry paper blotters or absorbent towels toremove excess fuel. To blot, press firmly (about 5 lb force) 3 or 4 times with heel of hand, moving the pad with tweezers eachtime.9.1.1 For maximum accuracy the test pad should be read within 3 min after sampling is initiated. If the test pad is not readimmediately after sampling, it must be placed in a desiccator to prevent moisture pickup from the air. However, ratings made ondried test pads, that is, not damp with fuel, should be avoided if possib
