1、Designation: D5950 12Standard Test Method forPour Point of Petroleum Products (Automatic Tilt Method)1This standard is issued under the fixed designation D5950; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. 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 automatic app
3、aratus.1. Scope*1.1 This test method covers the determination of pour pointof petroleum products by an automatic instrument that tilts thetest jar during cooling and detects movement of the surface ofthe test specimen with an optical device.1.2 This test method is designed to cover the range oftempe
4、ratures from 66 to +51C; however, the range oftemperatures included in the 1992 interlaboratory test programonly covered the temperature range from 39 to +6C, and therange of temperatures included in the 1998 interlaboratory testprogram was 51 to 11C. (See Section 13.)1.3 Test results from this test
5、 method can be determined at1 or 3C intervals.1.4 This test method is not intended for use with crude oils.NOTE 1The applicability of this test method on residual fuel sampleshas not been verified. For further information on applicability, refer to13.4.1.5 The values stated in SI units are to be reg
6、arded 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 theresponsibility of the user of this standard to establish appro-priate safety and health practices and determ
7、ine 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 Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6
8、708 Practice for StatisticalAssessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a Material2.2 Energy Institute Standard:3IP 15 Test Method for Pour Point of Petroleum Products3. Terminology3.1 Definitions:3.1.1 pour point, nin petroleu
9、m products, the lowesttemperature at which movement of the test specimen isobserved under the prescribed conditions of this test method.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 structu
10、re 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 structures or the viscosityincrease, or both, has progressed to the point where the applie
11、dobservation device no longer detects movement under theconditions of the test. The preceding observation temperature,at which flow of the test specimen is last observed, is the pourpoint.3.2.2 tiltingtechnique of movement where the test jar in avertical position is moved towards a horizontal positi
12、on toinduce specimen movement.3.2.2.1 DiscussionWhen the test jar is tilted and held in ahorizontal position for 5 s without detection of specimenmovement, this is the no-flow point and the test is complete.4. Summary of Test Method4.1 After preliminary heating, the test specimen is insertedinto the
13、 automatic pour point apparatus. After starting the1This 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 April 15, 2012. Published August 2012. Originall
14、yapproved in 1996. Last previous edition approved in 2007 as D595002(2007).DOI: 10.1520/D5950-12.2For 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 Docum
15、ent Summary page onthe ASTM website.3Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K., http:/www.energyinst.org.uk.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 194
16、28-2959, United States.program, the specimen is cooled according to the coolingprofile listed in Table 1 and examined at either 1 or 3Cintervals. The lowest temperature at which movement ofspecimen is detected, by the automatic equipment, is displayedas the pour point.NOTE 2If the automatic pour app
17、aratuss preheat option is utilized,place the test specimen into the apparatus. After starting the program, theapparatus will automatically carry out the preliminary heating.5. Significance and Use5.1 The pour point of a petroleum product is an index of thelowest temperature of its utility for certai
18、n 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 This test method can determine the pour point of the te
19、stspecimen with a resolution of 1.0C.5.4 Test results from this test method can be determined ateither 1 or 3C intervals.5.5 This test method yields a pour point in a format similarto Test Method D97/IP 15 when the 3C interval results arereported.NOTE 3Since some users may wish to report their resul
20、ts in a formatsimilar to Test Method D97 (in 3C intervals) the precisions were derivedfor the temperatures rounded to the 3C intervals. For statements on biasrelative to Test Method D97, see 13.3.5.6 This test method has better repeatability and reproduc-ibility relative to Test Method D97/IP 15 as
21、measured in the1998 interlaboratory test program. (See Section 13.)6. Apparatus6.1 Optical Automatic Pour Point Apparatus4The auto-matic pour point apparatus described in this test methodconsists of a microprocessor controller that is capable ofcontrolling one or more independent test cells. The app
22、aratusshall include provisions for independently controlling thetemperature of each cell according to the specified coolingprofile, monitoring continuously the specimen temperature,and detecting any movement of the specimen during tilting (seeFig. 1). The instrument shall be operated according to th
23、emanufacturers instructions.6.2 Temperature Probe, IEC 751 Class A: D T=6(0.15 + 0.002 |T|), capable of measurement from +70 down to80C. The temperature probe shall be in the center of the testjar and the top of the platinum tip immersed 3 mm below thesurface of the oil.6.3 Test Jar, clear cylindric
24、al glass, flat bottom, 34 60.5-mm outside diameter, 1.4 6 0.15-mm wall thickness, 1206 0.5-mm height, thickness of the bottom 2.0 6 0.5-mm,marked with a line to indicate the sample height 54 6 0.5-mmabove the inside bottom.6.4 Jacket, brass, cylindrical, flat bottom, 113 60.2-mm indepth, 45 +0, 0.1-
25、mm inside diameter. It shall be cooledaccording to the cooling profile specified.6.5 Cooling System, either an external system equipped witha circulating pump and capable of maintaining a temperature atleast 10C below the last required jacket temperature level (seeTable 1 and Fig. 2), or an internal
26、 system capable of maintain-ing the required jacket temperatures (see Table 1 and Fig. 2).6.6 Cork Disk,66 0.2 mm thick to fit loosely inside thejacket. Felt may be used but special attention must be paid toavoid moisture in the felt disk. The felt disk must be driedbefore each test.6.7 Cork Ring, t
27、o fit snugly around the outside of the test jarand loosely inside the test cell. Its purpose is to prevent the testjar from touching the cooling jacket.4The sole source of supply of the ISL Model CPP97-6, CPP97-2, and CPP-5Gsknown to the committee at this time is ISL SA, BP 40, 14790 Verson, France.
28、 If youare aware of alternative suppliers, please provide this information to ASTMInternational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.TABLE 1 Jacket and Specimen Temperature Cooling ProfileSpecimen Temp
29、erature, C Jacket Temperature, C+27=ST+9 06 0.5+9=ST6 186 0.56=ST24 336 0.524=ST42 516 0.542=ST60 696 0.560=ST78 876 0.5FIG. 1 Optical Detection SystemD5950 1227. Reagents and Materials7.1 Methyl Alcohol, Anhydrous, for use as cooling mediumin circulating bath system, when used.7.2 Cleaning Solvents
30、, suitable for cleaning and drying thetest jar and test head, such as petroleum naphtha and hexane.(Warning: Flammable. Liquid causes eye burns. Vapor harm-ful. May be fatal or cause blindness if swallowed or inhaled.)8. Sampling8.1 Obtain a sample in accordance with Practice D4057 orPractice D4177.
31、8.2 Samples of very 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 jar unless its temperature is 70C or lower.NOTE 4In
32、 the event the sample has been heated above this tempera-ture, allow the sample to cool until its temperature is at least 70C beforetransferring.9. Preparation of Apparatus9.1 Prepare the instrument for operation in accordance withthe manufacturers instructions.9.2 Clean and dry the test head and te
33、st jar using suitablesolvents as prescribed by the manufacturer.9.3 Adjust the set-point of the cooling system, when neces-sary, to the appropriate temperature to cool the jackets to therequired temperatures (see Table 1).NOTE 5For most applications, when using an external cooling sys-tem, the recir
34、culating cooler will be set at its lowest operating temperature.10. Calibration and Standardization10.1 Ensure that all of the manufacturers instructions forcalibrating, checking, and operating the apparatus are fol-lowed.10.1.1 A test head simulator, Part No. V02306, is used tocalibrate the equipme
35、nt. The test head simulator uses precisionresistors in place of the PT 100 temperature probe to calibratethe jacket and specimen temperature electronics. Follow themanufacturers calibration instructions.10.2 A sample with a well documented pour point can beused to verify performance of the apparatus
36、. Alternatively, asample which has been extensively tested in a pour pointinterlaboratory study can be used.11. Procedure11.1 Pour the sample into the test specimen jar to the scribedmark. When necessary, heat the sample in a water bath or ovenuntil it is just sufficiently fluid to pour the sample i
37、nto the testspecimen jar. Samples with an expected pour point above 36Cor samples which appear solid at room temperature can beheated above 45C, but should not be heated above 70C (seeNote 4).11.2 Subject the test specimen to the following preliminarytreatment or use the instruments automatic prehea
38、t option.NOTE 6Residual fuels have been known to be sensitive to thermalhistory. In the case where a residual fuel sample is tested, refer to TestMethod D97 for sample treatment.11.2.1 When the expected pour point (EP) is known to be#33C, heat the test specimen to 45C in a bath or ovenmaintained at
39、48C.11.2.2 When the expected pour point (EP) is known to be33C, heat the test specimen to EP + 9C, or at least to 45Cbut no higher than 70C (see Note 4).11.3 Place a cork disk at the bottom of the jacket in therequired cell and fit a cork ring to the test jar. The cork ringshould be 25 6 3 mm above
40、the bottom of the test jar.11.4 Place the test jar in the selected test cell. Attach thedetector head according to the manufacturers instructions.11.5 Select the desired testing interval (1 or 3C).11.6 Enter the expected pour point (EP). If 3C testingintervals are chosen (11.5) you must enter an exp
41、ected pourpoint that is a multiple of 3C.11.7 Start the test in accordance with the manufacturersinstructions.11.8 At this point, the instrument shall monitor the testspecimen with the optical detector, adjusting the jacket tem-perature to the first temperature level (according to Table 1)and measur
42、ing the specimen temperature. The instrument shallautomatically change the jacket temperature in accordancewith the specimen temperature (according toTable 1).The timeto move the jacket temperature from one level to the next lowerlevel shall not exceed 200 s, for jacket temperatures down to52C. The
43、instrument shall start tilting the specimen (withoutremoving it from the jacket) in the prescribed manner when thetemperature of the test specimen is at 9C higher than theexpected pour point. If the specimen flows during the tiltingmovement, the no-flow point is not reached and the jacketreturns to
44、the waiting vertical position for the next test. The testFIG. 2 Test Jar Cooling Chamber and Cooling SystemD5950 123will continue until the jacket is in a complete horizontalposition and the detector does not detect any movement of thespecimen for 5 s. This temperature, the no-flow point, plus 1 or3
45、C (depending on the test interval selected) is the pour pointof the oil (see Fig. 1). When the pour point is determined, theinstrument shall display the pour point result and start to reheatthe test specimen.NOTE 7For lower jacket temperatures, the time to move from onejacket temperature level to th
46、e next jacket temperature should not exceed300 s. Maintain cooling system temperatures as low as possible to attainthese jacket temperatures in the shortest time period possible and utilizecooling system with cooling capacity capable to achieve the lowesttemperature of application.11.9 If the instru
47、ment detects the no-flow point on the firsttilting cycle (EP + 9C), disregard the result and start with 11.1using a higher expected pour point.11.10 Record the result as the pour point without anycorrection.NOTE 8Residual fuels have been known to be sensitive to thermalhistory. In the case where a r
48、esidual fuel sample is tested, refer to TestMethod D97 for sample treatment.12. Report12.1 Report the temperature recorded in 11.10 together withthe model and testing interval as pour point in accordance withTest Method D5950.13. Precision and Bias13.1 PrecisionThe precision of this test method as d
49、eter-mined by the statistical examination of the interlaboratory testresults is as follows:13.1.1 Pour Point at 3C Testing Intervals:13.1.1.1 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 method, exceed the following, only in onecase in twenty.3.9C13.1.1.2 ReproducibilityThe difference between twosing
