1、Designation: D2709 96 (Reapproved 2011)1Standard Test Method forWater and Sediment in Middle Distillate Fuels by Centrifuge1This standard is issued under the fixed designation D2709; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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.1NOTEAdded part of speech to term in
3、3.1.1 editorially in May 2011.1. Scope1.1 This test method covers the determination of the volumeof free water and sediment in middle distillate fuels havingviscosities at 40C (104F) in the range of 1.0 to 4.1 mm2/s(1.0 to 4.1 cSt) and densities in the range of 770 to 900 kg/m3.NOTE 1Fuels correspon
4、ding to Specification D975 Grades 1D and2D, Specification D2880 Grades 0-GT, 1-GT and 2-GT, and SpecificationD3699 Grades 1-K and 2-K will usually fall in this viscosity and densityrange. Test Method D1796 is intended for higher viscosity fuel oils.1.2 The values stated in SI units are to be regarde
5、d asstandard. The values given in parentheses are for informationonly.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 the
6、 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D396 Specification for Fuel OilsD975 Specification for Diesel Fuel OilsD1796 Test Method for Water and Sediment in Fuel Oils bythe Centrifuge Method (Laboratory Procedure)D2880 Specification for Gas Tur
7、bine Fuel OilsD3699 Specification for KerosineD4057 Practice for Manual Sampling of Petroleum andPetroleum Products3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 distillate fuel, na virgin or cracked or blend of virginand cracked distillate having a flash point greater than 3
8、8C.4. Summary of Test Method4.1 A 100-mL sample of the undiluted fuel is centrifuged ata relative centrifugal force of 800 for 10 min at 21 to 32C (70to 90F) in a centrifuge tube readable to 0.005 mL andmeasurable to 0.01 mL. After centrifugation, the volume ofwater and sediment which has settled in
9、to the tip of thecentrifuge tube is read to the nearest 0.005 mL and reported asthe volumetric percent water and sediment by centrifuge.5. Significance and Use5.1 This test method is used as an indication of water andsediment in middle distillate fuels such as Grade Nos. 1 and 2fuel oil (Specificati
10、on D396), Nos. 1-D and 2-D diesel fuel(Specification D975), and Nos. 0-GT, 1-GT, and 2-GT gasturbine fuels (Specification D2880).5.2 Appreciable amounts of water and sediment in a fuel oiltend to cause fouling of the fuel-handling facilities and to givetrouble in the fuel system of a burner or engin
11、e. An accumu-lation of sediment in storage tanks and on filter screens canobstruct the flow of oil from the tank to the combustor. Waterin middle distillate fuels can cause corrosion of tanks andequipment, and if detergent is present, the water can causeemulsions or a hazy appearance. Water is neces
12、sary to supportmicrobiological growth at fuel water-interfaces in fuel systems.6. Apparatus6.1 Centrifuge, capable of whirling two or more filledcentrifuge tubes at a speed which can be controlled to give arelative centrifugal force (rcf) of 800 6 60 at the tip of thetubes. The revolving head, trunn
13、ion rings, and trunnion cups,including the cushions, are to be soundly constructed towithstand the maximum centrifugal force capable of beingdelivered by the power source. The trunnion cups and cushionsshall support the tubes when the centrifuge is in motion. The1This test method is under the jurisd
14、iction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.14 on Stability and Cleanliness of Liquid Fuels.Current edition approved May 1, 2011. Published August 2011. Originallyapproved in 1968. Last previous edition approved in 2006 as D270
15、996(2006).DOI: 10.1520/D2709-96R11E01.2For 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 onthe ASTM website.1Copyright ASTM Interna
16、tional, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.centrifuge shall be enclosed by a metal shield or case strongenough to eliminate danger if any breakage occurs.6.2 The data in Table 1 can be used to determine thecentrifuge speed setting required for the cen
17、trifuge to meetrelative centrifugal force requirements for this method and wasdeveloped using the following equations:rpm 5 265 =rcf/d (1)where:rcf = relative centrifugal force, andd = diameter of swing, in inches, measured between tipsof opposite tubes when in rotating position orrpm 5 422=rcf/d (2
18、)where:rcf = relative centrifugal force, andd = diameter of swing, in centimetres, measured betweentips of opposite tubes when in rotating position.6.3 Centrifuge Tube, cone-shaped, 100-mL with capillarytip capable of measuring 0.01 mL and readable by estimationto 0.005 %.6.4 Centrifuge Tube, pear-s
19、haped, 100-mL, with tube tiphaving graduations of 0.01 mL over the range 0 to 0.2 mL.7. Sampling7.1 Sampling shall be consistent with the procedures ofPractice D4057.7.2 The sample for a laboratory test will normally be analiquot of a much larger sample taken for full or partialspecification testing
20、. The full sample should have been takenby a procedure consistent with Practice D4057. Allow thesample container and its content to equilbrate between 21 to32C (70 to 90F). In general, the chosen laboratory testtemperature should not be lower than that at which the fuel isstored or used as too low a
21、 temperature may cause free waterhaze to form from additional free water formation.8. Procedure8.1 Temperature ControlAfter the sample container andits contents have equilibrated to laboratory temperature, be-tween 21 to 32C (70 to 90F), agitate the full sample by handor preferably by a mechanical s
22、haker for 10 min to ensurehomogeneity. (WarningFlammable.)8.2 As soon as possible, to prevent losing any water orsediment, fill the centrifuge tube to the 100-mL mark directlyfrom the sample container. Stopper and place in a trunnion cupopposite another filled tube to establish a balanced condition,
23、and whirl 10 min at a speed sufficient to produce a relativecentrifugal force (rcf) of 800 6 60 at the tip of the whirlingtubes. (For the relationship between diameter of swings, rcf,and rpm, see Table 1.) Record the combined water andsediment at the bottom of the tube to the nearest 0.005 mL.9. Rep
24、ort9.1 Report the volume of the combined water and sedimentread from the tube as the percentage of the total sample, sincea 100-mL sample was used. Report results lower than 0.005 %as either 0 or 0.005 volume %.10. Precision and Bias310.1 PrecisionThe precision of the procedure in this testmethod, f
25、or measuring the volume percent amount of com-bined water and sediment in middle distillate fuels by centri-fuge was determined by a round robin test program performedby 6 individuals using 13 samples at a common site.NOTE 2Precision data for this test used pear-shaped tubes.10.1.1 RepeatabilityThe
26、difference between successivemeasured volume percent amounts of combined water andsediment obtained by the same operator using the samecentrifuge and type of pear shaped tube under constantoperating conditions on identical distillate fuel samples at thesame site would, in the long run and in the nor
27、mal and correctoperation of the test method, exceed 0.014 volume % in 1 casein 20.10.1.2 ReproducibilityThe difference between two singleindependent measurements of volume percent amounts ofcombined water and sediment obtained by different operator/centrifuge pairs using the same type of pear shaped
28、 tube onidentical distillate fuel samples at the same site would, in thelong run, in the normal and correct operation of the testmethod, exceed 0.041 volume % in 1 case in 20.10.2 BiasSince there is no accepted reference materialsuitable for determining the bias for this procedure for mea-suring wat
29、er, the bias is not available for this test method.11. Keywords11.1 centrifuge; centrifuge tube; distillate fuel; water andsediment3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1308.TABLE 1 Rotation Speeds Applicable for C
30、entrifugesof Various Diameters of SwingDiameters of SwingARpm at 500rcfRpm at 800rcfin. cm12 30.5 1710 216013 33.0 1650 208014 35.6 1590 200015 38.1 1530 193016 40.6 1480 187017 43.2 1440 182018 45.7 1400 177019 48.3 1360 172020 50.8 1330 168021 53.3 1300 164022 55.9 1270 160023 58.4 1240 156024 61.
31、0 1210 1530AMeasured between tips of opposite tubes when in rotating position.D2709 96 (2011)12ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determina
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34、r comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (sing
35、le or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D2709 96 (2011)13
