1、Designation: D 7346 07An American National StandardStandard Test Method forNo Flow Point of Petroleum Products1This standard is issued under the fixed designation D 7346; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、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.1. Scope1.1 This test method covers the determination of the no flowpoint temperature of petroleum products using an automaticins
3、trument.1.2 The measuring range of the apparatus is from -95 to45C, however the precision statements were derived onlyfrom samples with no flow point temperatures from -77 to+2C.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationon
4、ly.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 regulatory limitations prior to use.2. Reference
5、d Documents2.1 ASTM Standards:2D97 Test Method for Pour Point of Petroleum ProductsD 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD 6300 Practice for Determination of Precision and BiasData for Use in Tes
6、t Methods for Petroleum Products andLubricants3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 no-flow point, nin petroleum products, the tempera-ture of the test specimen at which a wax crystal structureformation or viscosity increase, or both, is sufficient to impedemovement
7、of the surface of the test specimen under theconditions of the test.3.1.1.1 DiscussionThe no-flow point occurs when, uponcooling, the formation of wax crystal structures or viscosityincrease, or both, have progressed to the point where theapplied observation device no longer detects movement underth
8、e conditions of the test.4. Summary of Test Method4.1 After inserting the test specimen into the automatic noflow point apparatus and initiating the program, the testspecimen is heated, if necessary, to a starting temperature andthen cooled by prescribed rates. The test specimen is continu-ously tes
9、ted for flow characteristics by continuously monitor-ing the air pressure variation inside the test specimen vial.When the specimen is still fluid, its movement will partiallycompensate for the reduction in air pressure in the test chamberabove the test specimen surface. At some temperature thepress
10、ure measuring system detects a pressure decrease due toincapability of the test specimen to flow caused by a crystalstructure formation in the specimen or its viscosity increase, orboth. This temperature is recorded as no flow point with aresolution of 0.1C. The test specimen is then reheated to all
11、owfor removal from the test chamber.5. Significance and Use5.1 The no flow point of a petroleum product is an index ofthe lowest temperature of its utility for some applications. Flowcharacteristics, such as no flow point, can be critical for theproper operation of lubricating systems, fuel systems,
12、 andpipeline operations.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved July 15, 2007. Published August 2007.2For referenced ASTM standards, visit
13、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 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959
14、, United States.5.2 Petroleum blending operations require precise measure-ment of the no flow point.5.3 This test method can determine the temperature of thetest specimen with a resolution of 0.1C at which eithercrystals have formed or viscosity has increased sufficiently, orboth, to impede flow of
15、the petroleum product.6. Apparatus (see Annex A1)6.1 Automatic No Flow Point Apparatus3The apparatusconsists of a microprocessorcontrolled test specimen chamberthat is capable of heating and cooling the test specimen atrequired rate, measuring the pressure inside the test specimenvial, and recording
16、 the temperature of the test specimenchamber. A detailed description of the apparatus is provided inAnnex A1.6.2 The apparatus shall be equipped with a thermostaticallycontrolled specimen chamber, digital display, cooling andheating systems, pressure measuring system, and a specimenchamber temperatu
17、re measuring device.6.3 The temperature measuring device in the specimenchamber shall be capable of measuring the temperature from-105 to 60C at a resolution of 0.1C.7. Reagents and Materials7.1 Specimen VialDisposable, clear glass cylinder withclosed flat bottom, 1 mL capacity.Dimensions:Outer diam
18、eter: 8.0 to 8.3 mmWall thickness: 0.75 to 0.85 mmOuter length: 39.25 to 40.25 mmNOTE 1Standard NWV type vial was found suitable for the applica-tion.7.2 Specimen Vial Stopper Disposable, proprietary de-signed for use in this apparatus.7.3 MicropipetteCapable of delivering 0.5 6 0.1 mL ofsample. Pos
19、itive displacement type micropipette with capillarypiston is preferred for use.Air-displacement type micropipettesare not recommended for viscous samples.8. Sampling8.1 Obtain a sample in accordance with Practice D 4057 orD 4177.8.2 At least 1 mL of sample is required for each test.8.3 Samples of ve
20、ry viscous materials can be warmed untilthey are reasonably fluid before they are transferred; however,no sample shall be heated more than is absolutely necessary.The sample shall not be heated and transferred into the testspecimen cup unless its temperature is 70C or lower.NOTE 2In the event the sa
21、mple has been heated above this tempera-ture, allow the sample to cool until its temperature is below 70C beforetransferring it.9. Preparation of Apparatus9.1 Prepare the apparatus for operation in accordance withthe manufacturers instructions.10. Calibration and Standardization10.1 Ensure that all
22、of the manufacturers instructions forcalibration of the mechanical and electronic systems andoperation of the apparatus are followed.10.2 To verify the performance of the apparatus, a samplefor which extensive data has been obtained by no flow pointtest method may be used. Such verification material
23、s can alsobe prepared from intra-company cross checks.11. Procedure11.1 Draw 0.5 6 0.1 mL of sample into a micropipette andtransfer the specimen into a new clean, dry specimen vial.When necessary, heat the sample in a water bath or oven untilit is just sufficiently fluid to transfer. Samples with an
24、 expectedno flow point above 25C or which appear solid at roomtemperature can be heated above 45C but shall not be heatedabove 70C (see Note 2).NOTE 3Some samples like residual fuels, black oils, and cylinderstock have been known to be sensitive to thermal history. In the casewhere such sample is te
25、sted, refer to Test Method D 97 for sampletreatment prior testing.11.2 Place a new clean, dry specimen vial stopper on thespecimen vial and insert the assembly into the apparatus. Startthe operation of the apparatus according to the manufacturersinstructions. When the expected no flow point of the s
26、pecimenis known, program it in the apparatus as EP (expected point)and start test sequence. From this point up to and including thetermination of the test, recording and reporting of the result, theapparatus automatically controls the procedure.11.3 The apparatus adjusts the specimen chamber to apre
27、selected starting temperature. By default, the preselectedstarting temperature is 25C. Alternatively, the operator canpreprogram a defined starting temperature between 25 and60C, if desired. When the expected no flow point is knownand programmed in the apparatus, the starting temperatureshall be at
28、least 30C warmer. In the event that the preselectedstarting temperature is programmed lower than 30C above theexpected no flow point, the apparatus shall heat the specimenchamber to a starting temperature at least 30C above theexpected no flow point, but not more than 60C.11.4 When the expected no f
29、low point of the specimen is notknown, once the starting temperature is reached (see 11.3) thespecimen chamber is cooled at a rate of 1.5 6 0.15C/min.11.5 At the same time the cooling begins, the pressuremeasurement system is engaged to continuously monitorspecimen behavior. When a decrease in press
30、ure, as determinedby the apparatus, is measured in the specimen vial, whichsignifies that the test specimen has ceased to flow due to acrystal structure formation in the specimen or its viscosityincrease, or both, the temperature of the specimen chamber isrecorded as the no flow point and held on a
31、digital display. Thetest chamber is than reheated and the test sequence is termi-nated.3The sole source of supply of the apparatus known to the committee at this timeis ISL model MPP 5Gs Analyzer, available from ISL, B.P. 70285 14653 Verson,France. If you are aware of alternative suppliers, please p
32、rovide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.D734607211.6 When a no flow point is detected prematurely, asdetermined by the apparatus, the specimen is automatical
33、lyreheated to a higher starting temperature, at least 30C warmerthan the temperature of premature detection, and then cooled asdescribed in 11.4 until the no flow point is detected asdescribed in 11.5.NOTE 4Some typical examples of premature no flow point are: whenthe NFP is detected during the fast
34、 cooling phase or when the NFP isdetected less than 30C from the starting temperature.11.7 When the expected no flow point of the specimen isknown, and programmed into the apparatus, once the startingtemperature (see 11.3) is reached, the specimen chamber iscooled at a rate of 10 6 1C/min until 30C
35、warmer than theprogrammed expected no flow point, then the cooling rate isadjusted to 1.5 6 0.15C/min and the no flow point tempera-ture is detected as described in 11.5.12. Report12.1 Report the temperature recorded in 11.5 with resolu-tion of 0.1C, as the no-flow point in accordance with TestMetho
36、d D 7346.13. Precision and Bias13.1 PrecisionThe precision of this test method as deter-mined by the statistical examination of the interlaboratory4testresults is as follows:13.1.1 RepeatabilityThe difference between two resultsobtained by the same operator with the same apparatus underconstant oper
37、ating conditions on identical test material would,in the long run, in the normal and correct operation of this testmethod, exceed the following only in one case in twenty.1.93C13.1.2 ReproducibilityThe difference between two singleand independent results obtained by different operators work-ing in d
38、ifferent laboratories on identical test material would, inthe long run, in the normal and correct operation of this testmethod, exceed the following only in one case in twenty.2.62C13.2 BiasBecause there are no liquid hydrocarbon mix-tures of known no flow point, bias cannot be established.13.3 The
39、precision statements were derived according toPractice D 6300 from a 2006 interlaboratory cooperative testprogram.4Participants analyzed blind replicates of 38 samplesets comprised of; base oils, formulated engine oils bothmineral and synthetic, various lubricating oils, various aviationfuels, diese
40、l fuels, fuel oils, biodiesel, and biodiesel blend overthe temperature range of 77 to +2C. Thirteen laboratoriesparticipated with the automatic no flow point apparatus. Theprecision statistics were compiled and calculated based on the0.1C resolution results. Information on the types of samplesand th
41、eir respective average no flow point is contained in theresearch report.414. Keywords14.1 no flow point; petroleum productsANNEX(Mandatory Information)A1. AUTOMATIC NO FLOW POINT APPARATUSA1.1 GeneralThe microprocessor controlled test appara-tus, described in A1.2, and illustrated in Figs. A1.1 and
42、A1.2.A1.2 The apparatus shall be equipped with a thermostati-cally controlled specimen chamber, digital display, cooling andheating systems, pressure measuring system, and a specimenchamber temperature measuring device, arranged in a configu-ration as shown in Fig. A1.2.A1.2.1 Specimen ChamberCompri
43、sed of an aluminumblock bored with a hole of 10.0 6 0.2 mm on a length of 35 61 mm. See Fig. A1.1.A1.2.2 Temperature SensorCapable of reading to 0.1Cover the range -105 to 60C with a maximum error of 0.1C.The sensor shall be embedded into the wall of the specimenchamber and located in a position to
44、predict accurately thespecimen temperature.A1.2.3 Cooling SystemAn integral cooling system, ca-pable of controlling the specimen chamber temperature withinthe range of anticipated test temperatures with a 0.1C accu-racy.A1.2.4 Heating SystemCoupled to the specimen chambercapable of controlling the s
45、pecimen chamber temperaturewithin the range of anticipated test temperatures with a 0.1Caccuracy.A1.2.5 Pressure Measuring SystemAn electronic trans-ducer connected to the inner tube of specimen vial stopper andcapable of measuring the variation of air pressure above thetest specimen surface up to 2
46、 kPa with resolution of 1 Pa andaccuracy of 5 Pa.A1.2.6 Apparatus Exterior InterfaceThe exact layoutmay vary. A typical apparatus is shown as an example (see Fig.A1.3).4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D021620.D73
47、46073FIG. A1.1 Specimen ChamberFIG. A1.2 Principle of ApparatusD7346074ASTM 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
48、any such patent rights, 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
49、 invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your 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-
copyright@ 2008-2019 麦多课文库（www.mydoc123.com）网站版权所有
备案/许可证编号：苏ICP备17064731号-1