1、Designation: D 3142 05Standard Test Method forSpecific Gravity, API Gravity, or Density of Cutback Asphaltsby Hydrometer Method1This standard is issued under the fixed designation D 3142; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, 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.1. Scope1.1 This test method covers the laboratory determination,using a glass hydrometer, of the density, speci
3、fic gravity, orAPI gravity of cutback asphalts as defined in SpecificationsD 2026, D 2027, and D 2028 (Note 1). Values are measured ona hydrometer at convenient temperatures, readings of density,specific gravity, andAPI gravity being reduced to 15C or 60Fby means of international standard tables. By
4、 means of thesesame tables, values determined in one of the three systems ofmeasurement are convertible to equivalent values in eithersystem so that measurements may be made in the units of localconvenience.NOTE 1This test method is applicable to cutback asphalts and ingeneral follows, but provides
5、more explicit routines than, the procedureoutlined in Test Method D 1298.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This sta
6、ndard 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. Specific precau-tionary st
7、atements are given in Section 7.2. Referenced Documents2.1 ASTM Standards:2C 670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsD 140 Practice for Sampling Bituminous MaterialsD 1250 Guide for Use of the Petroleum MeasurementTablesD 1298 Test Method fo
8、r Density, Relative Density (SpecificGravity), or API Gravity of Crude Petroleum and LiquidPetroleum Products by Hydrometer MethodD 2026 Specification for Cutback Asphalt (Slow-CuringType)D 2027 Specification for Cutback Asphalt (Medium-CuringType)D 2028 Specification for Cutback Asphalt (Rapid-Curi
9、ngType)E1 Specification for ASTM Liquid-in-Glass ThermometersE 100 Specification for ASTM HydrometersE 220 Test Method for Calibration of Thermocouples ByComparison Techniques3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 API gravitya function of specific gravity 60/60F,repre
10、sented by the equation:API 5141.5/SG 60/60F! 131.5No statement of reference temperature is required since 60F isincluded in the definition.3.1.2 densityThe mass of material per unit volume. Whenreporting results, explicitly state the density in units of mass(kilograms) and volume (litres), together
11、with the standardreference temperature.3.1.3 observed valuesvalues observed at temperaturesother than the standard reference temperature. Values observedat other temperatures are only hydrometer readings, and notdensity, relative density (specific gravity), or API gravity.3.1.4 specific gravityThe r
12、atio of mass of a given volumeof a material at a specified temperature to the mass of an equalvolume of pure water measured at the reference temperature.When reporting results, the standard reference temperaturemust be stated.1This test method is under the jurisdiction of ASTM Committee D04 on Roada
13、nd Paving Materials and is the direct responsibility of Subcommittee D04.47 onMiscellaneous Asphalt Tests.Current edition approved June 1, 2005. Published July 2005. Originally approvedin 1972. Last previous edition approved in 1997 as D 3142 97.2For referenced ASTM standards, visit the ASTM website
14、, 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, United States.
15、4. Summary of Test Method4.1 The sample is brought to the testing temperature andtransferred to a hydrometer cylinder at approximately the sametemperature. The cylinder and its contents are placed in aconstant-temperature bath to avoid excessive temperaturevariation during the test. The appropriate
16、hydrometer is low-ered into the sample and allowed to settle. After temperatureequilibrium, the hydrometer is read and the temperature of thesample is noted.4.2 The hydrometer reading is corrected to either 15C or60F by referring to standard tables.5. Significance and Use5.1 Accurate determination o
17、f the density, specific gravity,or API gravity of cutback asphalts is necessary for theconversion of measured volumes to volumes at the standardtemperature of 15C or 60F.5.2 Similarly, accurate determination is necessary for con-verting volumes to mass as required in other ASTM tests oncutback aspha
18、lts.5.3 Values corrected to 15C and 60F will be differentbecause the two temperatures are not equal.6. Apparatus6.1 Hydrometers, glass, graduated in units of specific grav-ity, API gravity, or density as required, as listed in Table 1 andin accordance with Specification E 100.6.2 ThermometersA calib
19、rated ASTM Gravity Thermom-eter, having a range of 20 to 102C or 5 to 215F andconforming to the requirements for Thermometer 12C or 12F,respectively, as prescribed in Specification E1, or an equiva-lent thermometric device that has been calibrated in accordancewith Test Method E 220. If a thermohydr
20、ometer is used, thetemperature scale shall have a range from 20 to 65C or 60 to220F (Designation H).6.3 Hydrometer Cylinder, clear glass, plastic (Note 2), ormetal. For convenience in pouring, the cylinder may have a lipon the rim. The inside diameter of the cylinder shall be at least20 mm (34 in.)
21、greater than the outside diameter of thehydrometer used in it. The height of the cylinder shall be suchthat the hydrometer floats in the sample with at least 25 mm(1 in.) clearance between the bottom of the hydrometer and thebottom of the cylinder.NOTE 2Hydrometer cylinders constructed of plastic ma
22、terials shouldbe resistant to discoloration or attack by oil samples and must not becomeopaque by prolonged exposure to sunlight and oil samples.6.4 Constant-Temperature Bath, capable of maintaining thetesting temperature to 60.5C (1.0F) and of such dimensionsthat the level of the liquid is approxim
23、ately the same as that ofthe sample in the hydrometer cylinder.6.5 Oven, for preheating the sample, and capable of main-taining the selected testing temperature to within 63C (5F).7. Hazards7.1 Materials tested using this procedure may contain vola-tile and flammable hydrocarbons. Heat the sample in
24、 a coveredcontainer to minimize loss of volatile components. Carry outthe test in a well ventilated area, and avoid breathing anyvapors which may be generated. Keep sources of ignition awayfrom materials being tested.8. Sampling8.1 Take samples in accordance with Practice D 140. Thesample shall be f
25、ree of foreign substances.8.2 Thoroughly mix the sample before removing a repre-sentative portion for testing.9. Temperature of Test9.1 Because of differences in viscosity between variousgrades of cutback asphalts, the temperature of the test must beadjusted so that it will provide sufficient fluidi
26、ty to conduct thetest over a reasonable period of time. The recommended testingtemperatures for the various grades shown in Table 2 are basedon a viscosity of approximately 200 to 500 mm2/s (cSt).9.2 When the hydrometer value is to be used to selectmultipliers for correcting volumes to standard temp
27、eratures,the hydrometer reading should be made preferably at atemperature within 63C (5F) of the temperature at which thebulk volume of the oil was measured (Note 3). However, incases when appreciable amounts of light fractions may be lostduring determination at the bulk asphalt temperature, thetemp
28、eratures given in Table 2 should not be exceeded.NOTE 3When metal cylinders are used, accurate reading of thehydrometer can only be ensured if the level of the sample is within 5 mm(14 in.) of the top of the cylinder.10. Procedure10.1 Select the test temperature in accordance with theindications giv
29、en in Section 9. Heat the sample in an oven towithin 3C (5F) of the test temperature but without exceedingit. Cover the container with a loose-fitting cover to preventTABLE 1 Recommended HydrometersHydrometerDesignationMeasurement RangeTotalLength,mmBodyDiameter,mm1H to 4H API Gravity 1 to 41API 325
30、-335 23-2721H to 28H API Gravity 0 to 41API 158-168 12-1585H to 90H Relative Density(SG) 15.6/15.6C0.8 to 1.1 325-335 23-27105H to 108H Relative Density(SG) 15.6/15.6C0.8 to 1.0 250-270 20-24315H to 320H Density at 15C 800-1100 kg/m3325-335 21-27TABLE 2 Recommended Testing Temperatures for VariousGr
31、ades of Cutback AsphaltsGradeTestingTemperature, FTestingTemperature, CMC-30 Room RoomSC-70, MC-70, RC-70 104 40SC-250, MC-250, RC-250 140 60SC-800, MC-800, RC-800 176 80SC-3000, MC-3000, RC-3000 212 100D3142052solvent evaporation. Bring the hydrometer cylinder and ther-mometer to approximately the
32、same temperature as the sampleto be tested.10.2 Transfer the sample to a clean hydrometer cylinder(Note 4) without splashing, to avoid the formation of airbubbles, and to reduce to a minimum the evaporation of thelower boiling constituents of the more volatile samples. Re-move any air bubbles formed
33、, after they have collected on thesurface of the sample, by touching them with a piece of cleanfilter paper before inserting the hydrometer.NOTE 4Volume and density correction tables are based on an averagecoefficient of expansion for a number of typical materials. Since the samecoefficients were us
34、ed in computing both sets of tables, corrections madeover the same temperature interval minimize errors arising from possibledifferences between the coefficients of the material under test and thestandard coefficients. This effect becomes more important as temperaturesdiverge significantly from the
35、standard table temperatures of 15C or 60F.10.3 Place the cylinder containing the sample in theconstant-temperature bath previously brought up to the testtemperature 60.5C (1.0F). Allow sufficient time for thesample to reach the bath temperature 6 0.5C (1.0F) andverify its temperature with the thermo
36、metric device. If athermohydrometer is used, it may be lowered into the sampleat this point instead of the thermometric device. As soon as asteady thermometer reading is obtained, record the temperatureof the sample to the nearest 0.2C (0.5F).10.4 Lower the hydrometer gently into the sample. Takecar
37、e to avoid wetting the stem above the level to which it willbe immersed in the liquid. Allow sufficient time for thehydrometer to become completely stationary and for all airbubbles to come to the surface. This is particularly necessary inthe case of the more viscous samples.10.5 When the hydrometer
38、 has come to rest, floating freelyaway from the walls of the cylinder, read the hydrometer to thenearest scale division. Take the reading by observing with theeye slightly above the plane of the surface of the liquid, thepoint on the hydrometer scale to which the sample rises. Thisreading, at the to
39、p of the meniscus, requires correction sincehydrometers are calibrated to be read at the principal surface ofthe liquid. The corrections for the particular hydrometer in usemay be determined by observing the maximum height abovethe principal surface of the liquid to which oil rises on thehydrometer
40、scale when the hydrometer in question is immersedin a transparent oil having a surface tension similar to that ofthe sample under test. For routine work, determine the heightof the meniscus by sighting across the principal surface of theliquid and estimating the rise of the meniscus on the hydrom-et
41、er scale.10.6 Immediately after observing the hydrometer scalevalue, cautiously stir the sample with the thermometric device.Record the temperature of the sample to the nearest 0.2C(0.5F) (Note 5). Should this temperature differ from theprevious reading by more than 0.5C (1.0F), repeat thehydrometer
42、 and the temperature observations until the tem-perature becomes stable within 0.5C (1.0F).NOTE 5After use at a temperature higher than 40C (100F), allow allhydrometers of the lead shot in wax type to drain and cool in a verticalposition.11. Calculation11.1 Apply any relevant corrections to the obse
43、rved ther-mometer reading (for scale and bulb) and to the hydrometerreading (scale). Make the appropriate correction to the ob-served hydrometer reading. Record the specific gravity to thenearest 0.001, theAPI gravity to the nearest 0.1, or the densityto the nearest 1 kg/m3. After application of any
44、 relevantcorrections, record to the nearest 0.5C (1.0F) the mean of thetemperature values observed immediately before and after thefinal hydrometer reading.11.2 To convert the observed hydrometer reading to densityto standard temperature, use the following guidance to selectthe correct table from Gu
45、ide D 1250 and ASTM D 1250Petroleum Measurement Tables:3,411.2.1 When an API gravity hydrometer has been used, useTable 5A to convert the hydrometer reading to the API gravity.Then, if desired, use Table 3 to obtain the specific gravity60/60F or the density at 15C.11.2.2 When a specific gravity hydr
46、ometer has been used,use Table 23Ato convert the hydrometer reading to the specificgravity 60/60F. Then, if desired, use Table 21 to obtain theAPI gravity at 60F or the density at 15C.11.2.3 When a density scaled hydrometer has been used, useTable 53A to obtain the density at 15C. Then, if desired,
47、useTable 51 to obtain specific gravity 60/60F or API gravity at60F.12. Report12.1 Report the final value as specific gravity 60/60F, ordensity at 15C, kg/m3, or as gravity in degrees API, asapplicable.13. Precision and Bias13.1 Single Operator PrecisionThe single-operator stan-dard deviation for the
48、 specific gravity of cutback asphalts hasbeen found to be 0.00195. Therefore, results of two properlyconducted tests by the same operator on the same materialshould not differ by more than 0.0055 for specific gravity60/60F, 5.5 kg/m3for density at 15C, or 1.1 for API gravityat 60F.13.2 Multilaborato
49、ry PrecisionThe multilaboratory stan-dard deviation for the specific gravity of cutback asphalts hasbeen found to be 0.00276. Therefore, results of two properlyconducted tests by two laboratories on samples of the samematerial should not differ by more than 0.0078 for specificgravity 60/60F, 7.8 kg/m3for density at 15C, or 1.1 for APIgravity at 60F.NOTE 6These numbers represent the 1S and D2S limits as describedin Practice C 670.3Petroleum Measurement Tables, approved by International Standards Orga
