1、Designation: D 2709 96 (Reapproved 2006)An American National StandardStandard Test Method forWater and Sediment in Middle Distillate Fuels by Centrifuge1This standard is issued under the fixed designation D 2709; the number immediately following the designation indicates the year oforiginal adoption
2、 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 Defense.1. Sco
3、pe1.1 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 corresponding to Specification D 975 Grades 1
4、D and2D, Specification D 2880 Grades 0-GT, 1-GT and 2-GT, and SpecificationD 3699 Grades 1-K and 2-K will usually fall in this viscosity and densityrange. Test Method D 1796 is intended for higher viscosity fuel oils.1.2 The values stated in SI units are to be regarded as thestandard. The values giv
5、en 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 applica-bility of regulator
6、y limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 396 Specification for Fuel OilsD 975 Specification for Diesel Fuel OilsD 1796 Test Method for Water and Sediment in Fuel Oils bythe Centrifuge Method (Laboratory Procedure)D 2880 Specification for Gas Turbine Fuel OilsD 3699 Spe
7、cification for KerosineD 4057 Practice for Manual Sampling of Petroleum andPetroleum Products3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 distillate fuela virgin or cracked or blend of virginand cracked distillate having a flash point greater than 38C.4. Summary of Test Met
8、hod4.1 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 into the tip of thecentrifu
9、ge 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 (Specification D 396), Nos. 1-D and 2
10、-D diesel fuel(Specification D 975), and Nos. 0-GT, 1-GT, and 2-GT gasturbine fuels (Specification D 2880).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 engine. An accumu-lation of
11、 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 necessary to supportmicrobi
12、ological 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, trunnion rings, and trunnio
13、n 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. Thecentrifuge shall be enclosed by a metal shield or case stro
14、ngenough to eliminate danger if any breakage occurs.1This test method is under the jurisdiction 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, 2006. Publishe
15、d June 2006. Originallyapproved in 1968. Last previous edition approved in 2001 as D 2709 96 (2001)e1.2For 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
16、Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 The data in Table 1 can be used to determine thecentrifuge speed setting required for the centrifuge to meetrelative centrifugal force requi
17、rements 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)where:rcf = relative centrifugal force, andd =
18、 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-shaped, 100-mL, with tube tiphaving graduations
19、of 0.01 mL over the range 0 to 0.2 mL.7. Sampling7.1 Sampling shall be consistent with the procedures ofPractice D 4057.7.2 The sample for a laboratory test will normally be analiquot of a much larger sample taken for full or partialspecification testing. The full sample should have been takenby a p
20、rocedure consistent with Practice D 4057. 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 temperature may cause free waterhaze to form
21、 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 shaker for 10 min to ensurehomogeneity. (Warni
22、ngFlammable.)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,and whirl 10 min at a speed sufficient to pro
23、duce 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. Report9.1 Report the volume of the combined wate
24、r 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 Bias3,410.1 PrecisionThe precision of the procedure in this testmethod, for measuring the volume percent amount of c
25、om-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.10.1.1 RepeatabilityThe difference between successivemeasured volume percent amounts of combined water andsediment obtained b
26、y 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 normal and correctoperation of the test method, exceed 0.014 volume % in 1 casein 20.10.1.2 Reproducibil
27、ityThe 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 tube onidentical distillate fuel samples at the same site would, in thelong run, in the normal and c
28、orrect 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 water, the bias is not available for this test method.11. Keywords11.1 centrifuge; centrifuge tube; dist
29、illate fuel; water andsediment3Precision data for this test used pear-shaped tubes.4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D02-1308.TABLE 1 Rotation Speeds Applicable for Centrifugesof Various Diameters of SwingDiameter
30、s 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 61.0 1210 1530AMeasured between tips of opposite t
31、ubes when in rotating position.D 2709 96 (2006)2ASTM 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 determination of the validity of any such patent rights,
32、 and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for rev
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34、 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 (single 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).D 2709 96 (2006)3
