1、Designation: D3944 88 (Reapproved 2005)D3944 12Standard Test Method forSolidification Point of Petroleum Wax1This standard is issued under the fixed designation D3944; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This test method covers a procedure for rapidly determining the solidification point of petroleum wax.NOTE 1This t
3、est method is also applicable to similar materials such as synthetic waxes but the precision may vary.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 This standard does not purport to address all of the safety problem
4、s, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D87 Test Method for Melting Point of Petroleu
5、m Wax (Cooling Curve)D127 Test Method for Drop Melting Point of Petroleum Wax, Including PetrolatumD938 Test Method for Congealing Point of Petroleum Waxes, Including PetrolatumE1 Specification for ASTM Liquid-in-Glass Thermometers3. Terminology3.1 Definitions: Related to This Standard:3.1 Definitio
6、ns of Terms Specific to This Standard:3.1.1 solidification point of petroleum wax, nthat temperature in the cooling curve of the wax where the slope of the curvefirst changes significantly as the wax sample changes from a liquid to a solid state.3.2 solidification point of petroleum waxthat temperat
7、ure in the cooling curve of the wax where the slope of the curve firstchanges significantly as the wax sample changes from a liquid to a solid state.4. Summary of Test Method4.1 A 50-mg sample of wax is placed in a test tube at ambient temperature and heated above the solidification point of the wax
8、sample. A thermocouple probe, attached to a recorder, is inserted into the wax sample, which is allowed to cool at roomtemperature. The thermocouple response of the cooling wax traces a curve on the chart paper of the recorder. The first significantchange in the slope of the curve is the solidificat
9、ion point.5. Significance and Use5.1 The related methods of determining the melt point of petroleum wax are relatively time-consuming. This method endeavorsto reduce the duration of testing significantly and at the same time maintain a reasonable precision. This method can be useful forquality contr
10、ol of petroleum waxes as well as research and product development work on these waxes.5.2 For methods used for testing melt points of petroleum waxes, see Tests Method D87, D127, including Petrolatum and TestMethod D938.1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum
11、Products and Lubricants and is the direct responsibility of Subcommittee D02.10.0Aon Physical/Chemical Properties.Current edition approved May 1, 2005Dec. 1, 2012. Published May 2005February 2013. Originally approved in 1980. Last previous edition approved in 20002005 asD3944 88 (2000).D394488 (2005
12、). DOI: 10.1520/D3944-88R05.10.1520/D3944-12.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is
13、 not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropr
14、iate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
15、16. Apparatus6.1 Thermocouple, with an iron-constantan junction.36.2 Recorder, capable of recording voltage and equipped with a time-base module. The recorder should have the followingminimum specifications:6.2.1 Span, 0 to 10 mV or other suitable ranges.6.2.2 Accuracy, 0.25 % of full scale.6.2.3 St
16、ep Response Time, 1-s full scale, 3-s full scale is also appropriate.6.2.4 Zero Junction/Reference Junction/Temperature Compensated JunctionMust be included.6.3 TFE-Fluorocarbon Holder AdapterSee Fig. 1 and Fig. 2.46.4 TFE-Fluorocarbon Disk Centering GuideSee Fig. 1 and Fig. 2.46.5 Test Tubes, 6 by
17、50-mm.6.6 Vial, 25 by 52-mm.6.7 Apparatus for Calibrating Temperature Recorder:6.7.1 Stainless Steel Beaker, 1000-mL.6.7.2 Heating Mantle, to fit 6.7.1.6.7.3 Autotransformer to control heat to 6.7.2.6.7.4 Variable-Speed-Stirrer.6.7.5 Thermometer, Thermometer, ASTM No. 61C or 61F, 79-mm immersion.or
18、other temperature measuring device, asspecified in A1.1.6.8 Methods for Heating Specimen:6.8.1 Hot Air Blower at 1000 W, 1200 W, or other suitable power. This could be a laboratory or a household hair dryer type.3 Suitable thermocouples are available from: Claud S. Gordon Co., 5710 Kenosha St., Rich
19、mond, IL 60071, (815) 678-2211. For “J” (iron-constantan) junction thefollowing is suitable: Xactpak Type MM Assembly, Catalog No. 402-1101.Junction: grounded (G)Transition fitting: TH 2780-020Thermocouple wire: J30-1-305L (length of metal sheath)E (lead length): specify length desired.4 Not commerc
20、ially available and hence must be made in a machine shop or elsewhere.FIG. 1 Solidification Point ApparatusD3944 1226.8.2 Aluminum Heating Block, about 50 by 50 by 50 mm. In the center of one face of the block, a hole is made 7 mm indiameter and 37 mm deep to accommodate a 6 by 50-mm test tube and a
21、nother hole adjacent to it to accommodate a 110-V, 30-Wcartridge heater, about 9 by 38 mm, commercially available (see Fig. 2).6.8.2.1 Autotransformer, to control heat in 6.8.2.7. Procedure7.1 Calibrate the recorder at least every 60 days when in frequent use (see Annex A1).7.2 Obtain a wax sample r
22、epresentative of the material to be tested.7.3 Using a balance accurate to at least 1 mg, weight 50 + 5weigh 50 6 5 mg of sample by putting a few tiny pieces of solidwax into a tared 6- by 50-mm test tube.7.4 Start the temperature recorder. A horizontal pen speed of about 150 mm (5 in.)/10 min for a
23、 X-Y recorder or a chart speedof about 150 mm (5 in.)/10 min for a strip chart recorder is usually appropriate.7.5 Heat the sample by any convenient method, such as by use of:7.5.1 A hot air blower.7.5.2 An aluminum heating block.7.6 When using any method of heating a sample, note that the wax absor
24、bs heat slowly. Hence caution must be used not tooverheat the surface near the heating medium. Overheated wax can degrade. A minute amount of degradation affects results.7.7 When the sample melts, insert the thermocouple probe into the melted wax.7.8 Let the wax sample temperature rise 10 to 15C abo
25、ve the expected solidification point.7.9 Transfer the 6- by 50-mm test tube, together with its heated specimen, from the heating medium to a 25- by 52-mm vialwhich acts as a cooling chamber (See Fig. 1).7.10 Let the specimen cool until the curve traced by the cooling wax on the recorder chart paper
26、levels off.7.11 Determine the point in the curve which shows the first significant change in the slope of the curve (see Fig. 3). This is thesolidification point.8. Report8.1 Report the solidification point to the nearest 0.1C.9. Precision and Bias59.1 The precision of this test method as determined
27、 by statistical examination of interlaboratory results is as follows:5 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D02-1133.FIG. 2 Apparatus for Heating Wax SampleD3944 1239.1.1 RepeatabilityThe difference between two test r
28、esults, obtained by the same operator with the same apparatus underconstant operating conditions on identical material, would in the long run, in the normal and correct operation of the test method,exceed the following values only in one case in twenty:Distillate waxes 0.6 C (1.0 F)Residual waxes 0.
29、7 C (1.3 F)9.1.2 ReproducibilityThe difference between two single and independent results obtained by different operators working indifferent laboratories on identical test material would, in the long run, in the normal and correct operation of the test method,exceed the following values only in one
30、 case in twenty:Distillate waxes 1.2 C (2.2 F)Residual waxes 2.4 C (4.3 F)9.2 The precision data were obtained in an interlaboratory study involving five laboratories in which solidification points of fivedistillate waxes (51 to 69 C/123 to 155 F) and five residual waxes (53 to 85 C/128 to 185 F) we
31、re determined.9.3 BiasThe procedure in this test method has no bias because the value of solidification point can be defined only in termsof a test method.10. Keywords10.1 petroleum wax; solidification print; waxANNEX(Mandatory Information)A1. CALIBRATION OF RECORDERA1.1 Set up a calibration assembl
32、y consisting of a 1000 mL-beaker, with the thermocouple probe suspended in the center and witha thermometer or other thermometric device with equal or better accuracy suspended in a closely adjacent position at the properimmersion level. The thermometer thermometric device should have a range as sho
33、wn below and cover a range of 32 to 127C(90 to 260F). If used, mercury-in-glass thermometers shall conform to the requirements as prescribed in Specification E1, or inSpecifications for IP Standard Thermometers:Thermometer Range Thermometer Number32 to 127C90 to 260F61C61F32 to 127C 61C90 to 260F 61
34、FA1.2 Place hot water which is near boiling at about 95C in the beaker and stir thoroughly with a variable speed stirrer. Start theFIG. 3 A Typical CurveD3944 124recorder. As the water cools, record the exact thermometertemperature reading and the recorder pen reading (in millivolts), takinga series
35、 of readings at intervals of even 5C on the thermometer 5C intervals until the bath cools to 50C.A1.3 Plot a calibration curve, showing the pen reading on the abscissa (X-axis) and the corrected value (certified thermometerthermometric device readings) on the ordinate (Y-axis). Use this plot for obt
36、aining corrected solidification points.SUMMARY OF CHANGESSubcommittee D02.10 has identified the location of selected changes to this standard since the last issue(D394488 (2005) that may impact the use of this standard.(1) Revised 6.7.5.(2) Corrected 7.3.(3) Revised A1.1-A1.3.ASTM International take
37、s 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, and the riskof infringement of such rights, are entirely their own res
38、ponsibility.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 revision of this standard or for additional standardsand should be addresse
39、d 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
40、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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D3944 125
