1、Designation: D 5949 01e1An American National StandardStandard Test Method forPour Point of Petroleum Products (Automatic PressurePulsing Method)1This standard is issued under the fixed designation D 5949; the number immediately following the designation indicates the year oforiginal adoption or, in
2、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.e1NOTEFootnote 6 was updated editorially in August 2005.INTRODUCTIONThis test method covers an
3、alternative procedure for the determination of pour point of petroleumproducts using an automatic apparatus.1. Scope*1.1 This test method covers the determination of pour pointof petroleum products by an automatic instrument that appliesa controlled burst of nitrogen gas onto the specimen surfacewhi
4、le the specimen is being cooled and detects movement ofthe surface of the test specimen with an optical device.1.2 This test method is designed to cover the range oftemperatures from 57 to +51C. However, the range of tem-peratures included in the 1992 interlaboratory test programonly covered the tem
5、perature range from 39 to +6C and therange of temperatures included in the 1998 interlaboratory testprogram was from 51 to 11C. (see 13.4).1.3 Test results from this test method can be determined at1 or 3C testing intervals.1.4 This test method is not intended for use with crude oils.NOTE 1The appli
6、cability of this test method or residual fuel sampleshas not been verified. For further information on applicability, refer to13.4.1.5 The values stated in SI units are regarded as standard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It i
7、s 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. Referenced Documents2.1 ASTM Standards:D97 Test Method for Pour Point of Petroleum Products2D 4057 Practice for Manual Sam
8、pling of Petroleum andPetroleum Products3D 4177 Practice for Automatic Sampling of Petroleum andPetroleum Products32.2 IP Standard:IP15 Test Method for Pour Point of Petroleum Products43. Terminology3.1 Definitions:3.1.1 pour point, nin petroleum products, the lowesttemperature at which movement of
9、the test specimen isobserved under the prescribed conditions of the test.3.2 Definitions of Terms Specific to This Standard:3.2.1 no-flow point, nin petroleum products, the tempera-ture of the test specimen at which a wax crystal structure orviscosity increase, or both, impedes movement of the surfa
10、ceof the test specimen under the conditions of the test.3.2.1.1 DiscussionThe no-flow point occurs when, uponcooling, the formation of wax crystal structures or viscosityincrease, or both, has progressed to the point where the appliedobservation device no longer detects movement under theconditions
11、of the test. The preceding observation temperature,at which flow of the test specimen is last observed, is the pourpoint.3.2.2 pulse, na controlled burst of nitrogen gas of a fixedpressure and flow rate sufficient to cause movement on thesurface of the test specimen without fracturing the waxstructu
12、re which may be formed in the specimen.3.2.3 Peltier device, na solid-state thermoelectric deviceconstructed with dissimilar semiconductor materials, config-ured in such a way that it will transport heat to or away froma test specimen dependent on the direction of electric currentapplied to the devi
13、ce.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 Dec. 10, 2001. Published February 2002. Originallypublished as D 5949 96. Last previous edition
14、D 5949 96.2Annual Book of ASTM Standards, Vol 05.01.3Annual Book of ASTM Standards, Vol 05.02.4Available from Institute of Petroleum, 61 New Cavendish St., London, EnglandW1M 8AR.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, P
15、O Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 After inserting the test specimen into the automatic pourpoint apparatus, and initiation of the test program, the testspecimen is heated and then cooled by a Peltier device at a rateof 1.5 6 0.1C/min. At tempera
16、ture intervals of 1 or 3C,depending on the selection made by the user, a moving force inthe form of a pressurized pulse of nitrogen gas is imparted ontothe surface of the specimen. Multiple optical detectors are usedin conjunction with a light source to monitor movement of thesurface of the specimen
17、. The lowest temperature at whichmovement of the specimen surface is observed upon applica-tion of a pulse of nitrogen gas is recorded as the pour point,Test Method D 5949.5. Significance and Use5.1 The pour point of a petroleum product is an index of thelowest temperature of its utility for certain
18、 applications. Flowcharacteristics, like pour point, can be critical for the correctoperation of lubricating oil systems, fuel systems, and pipelineoperations.5.2 Petroleum blending operations require precise measure-ment of the pour point.5.3 In most cases, this test method does not require the use
19、of mechanical refrigeration apparatus (see 7.1).5.4 This test method yields a pour point in a format similarto Test Method D97/IP15 when the 3C interval results arereported.NOTE 2Since some users may wish to report their results in a formatsimilar to Test Method D97(in 3C intervals) the precisions w
20、ere derivedfrom the temperatures rounded to the 3 intervals. For statements on biasrelative to Test Method D97, see 13.3.5.5 Test results from this test method can be determined ateither 1 or 3C intervals.5.6 This test method has better repeatability and reproduc-ibility relative to Test Method D97/
21、IP15 as measured in the1992 and 1998 interlaboratory test programs.56. Apparatus6.1 Automatic Apparatus6The automatic pour point appa-ratus described in this test method consists of a microprocessorcontrolled test chamber that is capable of heating and coolingthe test specimen, providing a controlle
22、d pulse of nitrogen gasonto the specimen surface, optically detecting the specimensurface movement, and recording the temperature of thespecimen as described in detail in Annex A1. It is specificallydesigned to detect the lowest temperature at which movementof the surface of the specimen is observed
23、 upon application ofthe pulse.6.2 The apparatus shall be equipped with a specimen cup, anarray of optical detectors, light source, pressure pulsing unit,digital display, Peltier device, and a specimen temperaturemeasuring device.6.3 The pressure pulsing unit consists of a stainless steeltubing, 250
24、6 2 mm long and 1.1 6 0.1 mm inside diameter.This tubing is connected to a constant pressure source at oneend, which serves as an inlet. The other end of the tubing,which serves as the outlet, is bent and positioned such that it ispointing to the center of the specimen at an acute angle. Thedistance
25、 between the outlet and the center of the specimen is 86 2 mm.6.4 The Peltier device shall be capable of heating or coolingthe test specimen at a rate of 1.5 6 0.1C/min.6.5 The temperature measuring device in the specimen cupshall be capable of measuring the temperature of the testspecimen from 80 t
26、o +70C at a resolution of 0.1C.6.6 The apparatus shall be equipped with fittings to permitthe circulation of water or other liquid cooling media to removeheat generated by the Peltier device and other electroniccomponents of the apparatus.6.7 The apparatus shall be equipped with fittings to permitth
27、e delivery of nitrogen gas to the pressure pulsing unit.7. Reagents and Materials7.1 CoolantTap water or other liquid heat exchangemedium sufficient to remove heat generated by the Peltierdevice and other electronic components from the apparatus. Toachieve specimen cooling to 60C, supply circulation
28、 ofliquid cooling medium at +25C or lower to the apparatus.Obtain cooling performance data from the apparatus manufac-turer if lower specimen temperatures are desired or if the tapwater temperature is higher than 25C.7.2 Dry Nitrogen GasNitrogen gas with a dew pointbelow the lowest temperature attai
29、ned by the specimen(WarningCompressed gas.) (WarningInert gas can be anasphyxiant when inhaled.)7.3 Adjustable Volume Pipette,7capable of dispensing0.150 6 0.005 mL of sample.7.4 Cotton Swab,8plastic shaft cotton swabs to clean thesample cup.8. Sampling8.1 Obtain a sample in accordance with Practice
30、 D 4057 orby Practice D 4177.8.2 Samples of very viscous materials may be warmed untilthey are reasonably fluid before they are transferred; however,no sample shall be heated more than is absolutely necessary.5The results of this interlaboratory test program are available from ASTMInternational Head
31、quarters in the form of a research report. Request RR:D02-1312for the 1992 program and RR:D021499 for the 1998 program.6The following instrument has been found suitable for use in this test method:Phase Technology Pour Point Analyzer model series 30, 50, 70, 70V and 70X;available from Phase Technolo
32、gy, 11168 Hammersmith Gate, Richmond, B.C.CanadaV7A5H8. In the 1998 research report, the 70Vwas referred to as the currentmodel; whereas models 30, 50, and 70 were referred to as pre-1998 models. Thevarious model series mentioned above are differentiated by their cooling capacitiesand user interface
33、s; however, all of them are capable of covering the entiretemperature range specified in the scope.This pour point analyzer is covered by a patent. Interested parties are invited tosubmit information regarding the identification of an alternative to this patented itemto the ASTM International Headqu
34、arters. Your comments will receive carefulconsideration at a meeting of the responsible technical committee which you mayattend.7A suitable pipette is the Eppendorf pipette available from Brinkmann Instru-ments Inc., One Cantiague Rd., P.O. Box 1019, Westbury, NY 11590-0207.8Suitable cotton swabs ar
35、e Q-tips available from Cheesebrough Ponds, TrumbullCorp. Park, 55 Merritt Blvd., Trumbull, CT 06611.D594901e12The sample shall not be heated and transferred into the testspecimen cup unless its temperature is 70C or lower.NOTE 3In the event the sample has been heated above this tempera-ture, allow
36、the sample to cool until its temperature is at least 70C beforetransferring.9. Preparation of Apparatus9.1 Install the analyzer for operation in accordance with themanufacturers instructions.9.2 Turn on the liquid cooling medium and ensure itstemperature is appropriate for the specimen being tested
37、inaccordance with manufacturers instructions (see 7.1).9.3 Turn on the nitrogen gas and ensure that it is regulatedto the appropriate pressure in accordance with the manufactur-ers instructions.9.4 Turn on the main power switch of the analyzer.10. Calibration and Standardization10.1 Ensure that all
38、of the manufacturers instructions forcalibrating, checking, and operating the apparatus are fol-lowed.10.2 A sample with a well-documented pour point can beused to verify performance of the apparatus. Alternatively, asample which has been extensively tested in a pour pointinterlaboratory study can b
39、e used.11. Procedure11.1 Open the test chamber lid and clean the specimen cupinside the test chamber with a cotton swab.11.2 Use the pipette to deliver 0.150 6 0.005 mL ofspecimen into the specimen cup. Samples with an expectedpour point above 36C or which appear solid at room tempera-ture can be he
40、ated above 45C, but shall not be heated above70C (see Note 4). Clean the specimen out of the cup by usinga cotton swab. The cup shall be cleaned to the point where novisible droplets of specimen remain in the cup.11.3 Repeat step 11.2.11.4 Carefully measure 0.150 6 0.005 mL of the specimeninto the s
41、pecimen cup.11.5 Close and lock the test chamber lid.11.6 Follow the manufacturers instructions for preheatingthe specimen.11.7 Select the desired pour point testing interval: 1 or 3C.11.8 Start the test program following the manufacturersinstructions. The specimen is first heated as specified in 11
42、.6.Itis then cooled by the Peltier device at a rate of 1.5 60.1C/min. The apparatus will apply a pulse of pressurizednitrogen gas onto the specimen surface every 1 or 3C drop intemperature depending on the testing interval specified in 11.7.The specimen is illuminated by the light source, and themov
43、ement of the specimen surface upon application of a pulseis monitored by an array of optical detectors. The test willcontinue until application of a pulse of nitrogen gas causes noobservable movement on the specimen surface. This is theno-flow point of the specimen. The lowest temperature atwhich mo
44、vement of the specimen surface is observed uponapplication of the pulse of nitrogen gas is recorded as the pourpoint. The pour point value shall be displayed as an integertemperature in multiples of 1 or 3C depending on the selectedtesting interval.11.9 Unlock and open the test chamber lid and clean
45、 thespecimen out of the specimen cup with a cotton swab.12. Report12.1 Report the temperature recorded in 11.8 together withthe testing interval as pour point Test Method D 5949.13. Precision and Bias13.1 PrecisionThe precision of this test method as deter-mined by the statistical examination of the
46、 interlaboratory testresults5is as follows:13.1.1 RepeatabilityThe difference between successivetest results, obtained by the same operator using the sameapparatus under constant operating conditions on identical testmaterial, would in the long run, in the normal and correctoperation of this test me
47、thod, exceed the following values onlyin one case in twenty.1C Test Interval 3C Test IntervalModel 70V61.6C 2.2CModels 30, 50, 7062.9C 4.1C13.1.2 ReproducibilityThe difference between two singleand independent test results, obtained by different operatorsworking in different laboratories on identica
48、l test material,would in the long run, in normal and correct operation of thistest method, exceed the following values only in one case intwenty.1C Test Interval 3C Test IntervalModel 70V63.2C 3.8CModels 30, 50, 7066.2C 6.3C13.2 BiasSince there is no accepted reference materialsuitable for determini
49、ng the bias for the procedure in this testmethod, bias has not been determined.13.3 Relative Bias:13.3.1 Pour points at 3C testing intervals were compared tothe results from Test Method D 97. Relative bias5amongcertain samples was observed; however, the observed bias doesnot appear to be of a systematic nature. Biases relative to TestMethod D 97/IP15 may conceivably occur for sample types notincluded in the 1998 interlaboratory test program.NOTE 4Large differences in results were observed between methodsfor one samp
