1、Designation: D5949 16Standard Test Method forPour Point of Petroleum Products (Automatic PressurePulsing Method)1This standard is issued under the fixed designation D5949; 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 () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis test method covers an alternative procedure for the determination of pour point of petroleumproducts using an au
3、tomatic 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 surfacewhile the specimen is being cooled and detects movement ofthe surface of the test specimen wi
4、th an optical device.1.2 This test method is designed to cover the range oftemperatures from 57 C to +51 C. However, the range oftemperatures included in the 1992 interlaboratory test programonly covered the temperature range from 39 C to +6 C andthe range of temperatures included in the 1998 interl
5、aboratorytest program was from 51 C to 11 C. (see 13.4).1.3 Test results from this test method can be determined at1 C or 3 C testing intervals.1.4 This test method is not intended for use with crude oils.NOTE 1The applicability of this test method or residual fuel sampleshas not been verified. For
6、further information on applicability, refer to13.4.1.5 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibi
7、lity 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:2D97 Test Method for Pour Point of Petroleum ProductsD4057 Practice for Manual Sampling of Petrole
8、um andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a Material2.2 Energy Institute Standard:IP 15 Test Metho
9、d for Pour Point of Petroleum Products33. Terminology3.1 Definitions:3.1.1 pour point, nin petroleum products, the lowesttemperature at which movement of 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, n
10、in petroleum products, the tempera-ture of the test specimen at which a wax crystal structure orviscosity increase, or both, impedes movement of the surfaceof 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
11、 structures or viscosityincrease, or both, has progressed to the point where the appliedobservation device no longer detects movement under the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubco
12、mmittee D02.07 on Flow Properties.Current edition approved April 1, 2016. Published May 2016. Originallyapproved in 1996. Last previous edition approved in 2014 as D5949 14. DOI:10.1520/D5949-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at
13、serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K., http:/www.energyinst.org.uk.*A Summary of Changes section appears at the end of this sta
14、ndardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1conditions 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
15、of a fixedpressure and flow rate sufficient to cause movement on thesurface of the test specimen without fracturing the waxstructure 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
16、a way that it will transport heat to or away froma test specimen dependent on the direction of electric currentapplied to the device.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 a
17、nd then cooled by a Peltier device at a rateof 1.5 Cmin 6 0.1 Cmin. At temperature intervals of 1 Cor 3 C, depending on the selection made by the user, a movingforce in the form of a pressurized pulse of compressed gas isimparted onto the surface of the specimen. Multiple opticaldetectors are used i
18、n conjunction with a light source to monitormovement of the surface of the specimen. The lowest tempera-ture at which movement of the specimen surface is observedupon application of a pulse of compressed gas is recorded asthe pour point, Test Method D5949.5. Significance and Use5.1 The pour point of
19、 a petroleum product is an index of thelowest temperature of its utility for certain 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
20、-ment of the pour point.5.3 In most cases, this test method does not require the useof mechanical refrigeration apparatus (see 7.1).5.4 This test method yields a pour point in a format similarto Test Method D97/IP 15 when the 3 C interval results arereported.NOTE 2Since some users may wish to report
21、 their results in a formatsimilar to Test Method D97 (in 3 C intervals) the precisions were 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 C or 3 C intervals.5.6
22、This test method has better repeatability and reproduc-ibility relative to Test Method D97/IP 15 as measured in the1992 and 1998 interlaboratory test programs.46. Apparatus6.1 Automatic Apparatus5The automatic pour point appa-ratus described in this test method consists of a microprocessorcontrolled
23、 test chamber that is capable of heating and coolingthe test specimen, providing a controlled pulse of compressedgas onto the specimen surface, optically detecting the specimensurface movement, and recording the temperature of thespecimen as described in detail in Annex A1. It is specificallydesigne
24、d to detect the lowest temperature at which movementof the surface of the specimen is observed 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 tempe
25、raturemeasuring device.6.3 The pressure pulsing unit consists of a stainless steeltubing, 250 mm 6 2 mm long and 1.1 mm 6 0.1 mm insidediameter. This tubing is connected to a constant pressuresource at one end, which serves as an inlet.The other end of thetubing, which serves as the outlet, is bent
26、and positioned suchthat it is pointing to the center of the specimen at an acuteangle. The distance between the outlet and the center of thespecimen is 8 mm 6 2 mm.6.4 The Peltier device shall be capable of heating or coolingthe test specimen at a rate of 1.5 Cmin 6 0.1 Cmin.6.5 The temperature meas
27、uring device in the specimen cupshall be capable of measuring the temperature of the testspecimen from 80 C to +70 C at a resolution of 0.1 C.6.6 The apparatus, if required,5shall be equipped withfittings to permit the circulation of water or other liquid coolingmedia to remove heat generated by the
28、 Peltier device and otherelectronic components of the apparatus. Newer models5haveinternal sources of liquid cooling media and do not requiresuch fittings.6.7 The apparatus shall be equipped with fittings to permitthe delivery of nitrogen gas to the pressure pulsing unit. Newermodels5have internal s
29、ources of compressed gas and do notrequire such fittings.6.8 Ultrasonic Bath, Unheated(optional)with an oper-ating frequency between 25 kHz to 60 kHz and a typical poweroutput of 100 W, of suitable dimensions to hold container(s)4The results of this interlaboratory test program are available from AS
30、TMInternational Headquarters in the form of a research report. Request RR:D02-1312for the 1992 program and RR:D02-1499 for the 1998 program.5The 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;availabl
31、e from Phase Technology, 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 capacit
32、iesand user interfaces; however, all of them are capable of covering the entiretemperature range specified in the scope.Model series 30, 50, 70, and 70V require external sources of coolant andcompressed gas (dry nitrogen). Model series 70X has built-in internal sources ofcoolant and compressed gas.T
33、his 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 Headquarters. Your comments will receive carefulconsideration at a meeting of the responsible technical co
34、mmittee which you mayattend.D5949 162placed inside of bath, for use in effectively dissipating andremoving air or gas bubbles that can be entrained in viscoussample types prior to analysis. It is permissible to use ultra-sonic baths with operating frequencies and power outputsoutside this range, how
35、ever it is the responsibility of thelaboratory to conduct a data comparison study to confirm thatresults determined with and without the use of such ultrasonicbaths does not materially impact results.7. Reagents and Materials7.1 CoolantTap water or other liquid heat exchange me-dium sufficient to re
36、move heat generated by the Peltier deviceand other electronic components from the apparatus. Toachieve specimen cooling to 60 C, supply circulation ofliquid cooling medium at +25 C or lower, if required,5to theapparatus. Obtain cooling performance data from the apparatusmanufacturer if lower specime
37、n temperatures are desired or ifthe tap water temperature is higher than 25 C.7.2 Dry Nitrogen GasNitrogen gas with a dew pointbelow the lowest temperature attained by the specimen(WarningCompressed gas.)(WarningInert gas can be anasphyxiant when inhaled.) Newer models5have internalsources of compre
38、ssed gas and do not require external drynitrogen gas.7.3 Precision Volume-Dispensing Device, capable of dis-pensing 0.150 mL 6 0.005 mL of sample.7.4 Cotton Swab, plastic shaft cotton swabs to clean thesample cup.8. Sampling8.1 Obtain a sample in accordance with Practice D4057 orby Practice D4177.8.
39、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.The sample shall not be heated and transferred into the testspecimen cup unless its temperature is 70 C or lower.NOTE 3In
40、the event the sample has been heated above thistemperature, allow the sample to cool until its temperature is at least 70 Cbefore transferring.8.3 For some sample types, such as viscous lube oils that areprone to having entrained air or gas bubbles present in thesample, the use of an ultrasonic bath
41、 (see 6.8) without theheater turned on (if so equipped), has been found effective indissipating bubbles typically within 1 min.9. Preparation of Apparatus9.1 Install the analyzer for operation in accordance with themanufacturers instructions.9.2 Turn on the liquid cooling medium, if required,5andens
42、ure its temperature is appropriate for the specimen beingtested in accordance with manufacturers instructions (see 7.1).9.3 Turn on the nitrogen gas, if required,5and ensure that itis regulated to the appropriate pressure in accordance with themanufacturers instructions.9.4 Turn on the main power sw
43、itch of the analyzer.10. Calibration and Standardization10.1 Ensure that all 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
44、 which has been extensively tested in a pour pointinterlaboratory study can be used.11. Procedure11.1 Inspect the specimen cup to ensure that it is clean anddry. If needed, clean the cup in accordance with 11.3.11.2 Deliver 0.150 mL 6 0.005 mL of specimen into thespecimen cup. Pipettes, syringes, or
45、 precision positive-displacement devices are suitable for use in delivering thespecimen. Samples with an expected pour point above 36 C orwhich appear solid at room temperature may be heated above45 C, but shall not be heated above 70 C (see Note 4).11.3 Clean the specimen out of the cup. The cup sh
46、all becleaned to the point where no visible droplets of specimenremain in the cup. Non-abrasive absorbent materials, such ascotton swabs, are suitable for use in cleaning the specimen cup.Cleaning solvents able to clean the specimen and compatiblewith the components of the apparatus may also be used
47、.Naphtha, hexane, and heptane are suitable as cleaning solvents.11.4 Repeat steps 11.2 and 11.3.11.5 Carefully measure 0.150 mL 6 0.005 mL of thespecimen into the specimen cup.11.6 Close and lock the test chamber lid.11.7 Follow the manufacturers instructions for preheatingthe specimen.11.8 Select t
48、he desired pour point testing interval: 1 C or3 C.11.9 Start the test program following the manufacturersinstructions. The specimen is first heated as specified in 11.7.Itis then cooled by the Peltier device at a rate of 1.5 Cmin 60.1 Cmin. The apparatus will apply a pulse of compressedgas onto the
49、specimen surface every 1 C or 3 C drop intemperature depending on the testing interval specified in 11.8.The specimen is illuminated by the light source, and themovement 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 compressed gas causesno observable movement on the specimen surface. This is theno-flow point of the specimen. The lowest temperature atwhich movement of the specimen surface is observed uponappli
