1、Designation: D1480 12Standard Test Method forDensity and Relative Density (Specific Gravity) of ViscousMaterials by Bingham Pycnometer1This standard is issued under the fixed designation D1480; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 revision, the year of last 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*1.1 This test method covers two procedures for the mea-surement of the density of materials which
3、are fluid at thedesired test temperature. Its application is restricted to liquidsof vapor pressures below 600 mm Hg (80 kPa) and viscositiesbelow 40 000 cSt (mm2/s) at the test temperature. The methodis designed for use at any temperature between 20 and 100C.It can be used at higher temperatures; h
4、owever, in this case theprecision section does not apply.NOTE 1For the determination of density of materials which are fluidat normal temperatures, see Test Method D1217.1.2 This test method provides a calculation procedure forconverting density to specific gravity.1.3 The values stated in SI units
5、are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 WARNINGMercury has been designated by manyregulatory agencies as a hazardous material that can causecentral nervous system, kidney and liver damage. Mercury, orits vapor, may be hazardous to health and corr
6、osive tomaterials. Caution should be taken when handling mercury andmercury containing products. See the applicable product Ma-terial Safety Data Sheet (MSDS) for details and EPAswebsitehttp:/www.epa.gov/mercury/faq.htmfor addi-tional information. Users should be aware that selling mercuryand/or mer
7、cury containing products into your state or countrymay be prohibited by law.1.5 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 determi
8、ne the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1217 Test Method for Density and Relative Density (Spe-cific Gravity) of Liquids by Bingham PycnometerD4052 Test Method for Density, Relative Density, and APIGravity of Liquids by Digital Density
9、 MeterE1 Specification for ASTM Liquid-in-Glass Thermometers3. Terminology3.1 Definitions:3.1.1 density, nmass per unit volume at a specifiedtemperature. D40523.1.2 relative density, nthe ratio of the density of amaterial at a stated temperature to the density of water at astated temperature. D40524
10、. Summary of Test Method4.1 The liquid sample is introduced into the pycnometer,equilibrated to the desired temperature, and weighed. Thedensity or specific gravity is then calculated from this weightand the previously determined calibration factor, and a correc-tion is applied for the buoyancy of a
11、ir.5. Significance and Use5.1 Density is a fundamental physical property that can beused in conjunction with other properties to characterize boththe light and heavy fractions of petroleum and to assess thequality of crude oils.5.2 Determination of the density or relative density ofpetroleum and its
12、 products is necessary for the conversion ofmeasured volumes to volumes at the standard temperatures of15C.5.3 The determination of densities at the elevated tempera-tures of 40 and 100C is particularly useful in providing thedata needed for the conversion of kinematic viscosities in1This test metho
13、d is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.04.0D on Physical and Chemical Methods.Current edition approved Nov. 1, 2012. Published December 2012. Originallyapproved in 1957. Last previous edition approved
14、in 2007 as D148007. DOI:10.1520/D1480-12.2For 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 Document Summary page onthe ASTM website.*A Summary of Change
15、s section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1centistokes (mm2/s) to the corresponding dynamic viscositiesin centipoises (mPas).6. Apparatus6.1 Pycnometer,3Bingham-type of 10-mL capacity
16、(asshown in Fig. 1), constructed of heat-resistant4glass.NOTE 2Pycnometers having capacities of 2 to 25 mLare available buthave not been cooperatively evaluated.6.2 Constant-Temperature Bath, provided with suitable py-cnometer holders and means for maintaining temperaturesconstant to 60.01C in the d
17、esired range. Water-glycerinmixtures can be used for temperatures up to 100C.6.3 Bath Thermometer, graduated in 0.1C subdivisions andstandardized for the range of use to the nearest 0.01C (ASTMSaybolt Viscosity Thermometers 17C to 22C, conforming tothe requirements in Specification E1, are recommend
18、ed). Formost hydrocarbons the density coefficient is about 0.0008units/C, and therefore an error of 60.013C would cause anerror of 60.00001 in density. A standardized platinum resis-tance thermometer may also be used, and it offers the bestmeans for observing temperature changes in the bath.6.4 Ther
19、mal Shields, as shown in Fig. 2, to hold thepycnometer and syringe during the filling procedure, con-structed of two aluminum shells with suitably spaced viewingports, the upper bored to hold a 30-mLhypodermic syringe andthe lower bored to hold a 25-mL Bingham pycnometer. Awinding of No. 26 Chromel
20、“A” wire, insulated from theshields with mica, covered with insulating tape, and havingresistances connected in series of 25 on the upper shield and35 on the lower produces controlled heat to the shields bymeans of a variable transformer.Astand is necessary to supportthe shields in such a manner tha
21、t the center of the wells may bealigned, and the upper shield raised 180 to 200 mm and swungthrough 45.6.5 Hypodermic Syringes, 2 to 30-mL capacity, of chemi-cally resistant glass, equipped with a 170-mm, 16-gage (0.065in.) filling needle made from stainless-steel tubing, as shown inFig. 3.6.6 Draw-
22、off Needle, made of stainless-steel tubing, asshown in Fig. 3.6.7 Solvent Cleaning Assembly, as shown in Fig. 4.6.8 Chromic Acid Cleaning Apparatus, similar to thatshown in Fig. 5.3There is more than one supplier. If you cannot find a supplier, then contactSubcommittee D02.04.0D on Physical and Chem
23、ical Methods for possible suppli-ers.4Borosilicate glass has been found satisfactory for this purpose.FIG. 1 Bingham-Type PycnometerMetric Equivalentsin. mm in. mm in. mm in. mm18 3.258 15.9 114 31.8 4 10214 6.434 19.1 1716 36.5 434 121716 11.1 1132 26.2 178 47.6 538 13612 12.7 118 28.6 2 50.8 638 1
24、62714 184NOTE 1Cover shields with mica or insulating cement. Wind with No.26 gage Chromel “A” wire: Upper block 60 in. (1.52 m) (25.4), lowerblock 85 in. (2.16 m) (35.0) wound vertically. Cover with insulating tapeor insulating cement and connect heaters in series. Insulate shields fromstand with14-
25、in. Transite.FIG. 2 Details of Thermal Shields for 30-mL Syringe and 25-mLPycnometerD1480 1226.9 Balance, capable of reproducing weighings within 0.1mg when carrying a load of 30 g. The balance shall be locatedin a room shielded from drafts and fumes and in which thetemperature changes between relat
26、ed weighings (empty andfilled pycnometer) do not cause a significant change in the ratioof the balance arms. The same balance shall be used for allrelated weighings.6.10 Weights, whose relative values are known to thenearest 0.05 mg or better. Use the same set of weights for thecalibration of the py
27、cnometer and the determination of densi-ties.7. Reagents and Materials7.1 Acetone(WarningExtremely flammable. Use ad-equate ventilation.)7.2 Isopentane(WarningExtremely flammable. Avoidbuild up of vapors and remove all sources of ignition, espe-cially non-explosion proof electrical apparatus.)7.3 Ch
28、romic Acid (Potassium Dichromate/Conc. SulfuricAcid)(WarningCauses severe burns. A recognized car-cinogen. Do not get in eyes, on skin or clothing.)8. Preparation of Apparatus8.1 Clean the pycnometer thoroughly with hot chromic acidcleaning solution by means of the assembly shown in Fig. 5(WarningSe
29、e 7.3.) Chromic acid solution is the mosteffective cleansing agent. However, surfactant cleansing fluidshave also been used successfully. Mount the apparatus firmlyand connect the trap to the vacuum. Warm the necessaryamount of cleaning acid in the beaker, place the pycnometer onthe ground joint, an
30、d evacuate by opening the stopcock tovacuum. Fill the pycnometer with acid by turning the stop-cock, and either repeat several times, or remove the filledpycnometer and allow it to stand for several hours at 50 to60C. Remove the acid from the pycnometer by evacuation,empty the acid from the trap, an
31、d flush the pycnometer withdistilled water. Clean in this manner whenever the pycnometeris to be calibrated or whenever liquid fails to drain cleanly fromthe walls of the pycnometer or its capillary. Ordinarily, thepycnometer may be cleaned between determinations by wash-ing with a suitable solvent,
32、 rinsing with pure, dry acetone,followed by isopentane, and vacuum drying. (WarningSee7.1 and 7.2.)8.2 Transfer the pycnometer to the cleaner assembly shownin Fig. 4, with vacuum line and trap attached to the side tubeas indicated. Place the pycnometer on the cleaner with theupper hypodermic needle
33、extending upward into thepycnometer, and press the edge of the ground joint on therubber stopper until the vacuum holds it in place. Draw out allthe liquid or sample. Immerse the lower end of the hypodermicFIG. 3 Accessories for Bingham-Type PycnometerD1480 123tube in a suitable solvent and draw 20
34、to 25 mL through thepycnometer. Leaving the pycnometer in place, draw air throughit until it is dry. Clean the hypodermic syringe with the sameapparatus.9. Calibration of Pycnometers9.1 Weigh the clean, dry pycnometer to 0.1 mg and recordthe weight.FIG. 4 Cleaner Assembly for Bingham-Type Pycnometer
35、FIG. 5 All-Glass Pycnometer Cleaner Assembly for Use with Hot Chromic Acid Cleaning SolutionD1480 124NOTE 3It is convenient to use the lightest of a set of pycnometers asa tare. For best results the treatment and environment of both pycnometerand tare should be identical for some time prior to weigh
36、ing.9.2 With a syringe of suitable size, transfer freshly boiledand cooled distilled water to the pycnometer through the fillingneedle (Note 6). Avoid trapping air bubbles in the bulb orcapillary of the pycnometer, removing bubbles, as they form,with the syringe, when possible. Also remove any water
37、 abovethe calibration mark and dry the overflow chamber andcapillary with a cotton-fiber pipe cleaner or cotton swab whichhas been moistened slightly with acetone. Do not touch theplunger of the syringe or hypodermic needle with fingers asminute quantities of oil transferred this way would cause fau
38、ltydrainage in the capillary neck of the pycnometer.9.3 Close the pycnometer with the glass stopper and im-merse it to a point above the calibration mark in the constant-temperature bath adjusted to a constancy of 60.01C at thedesired temperature (Note 4). Periodically, or before the liquidexpands i
39、nto the overflow chamber, remove the stopper, raisethe pycnometer sufficiently to expose the calibration mark toview, and readjust the liquid level to the mark by withdrawingliquid through the steel draw-off needle until expansion hasstopped, indicating that the liquid has reached the temperatureof
40、the thermostat. To minimize errors caused by faultydrainage, do not allow the liquid to expand more than 10 mmabove the calibration mark at any time. Allow the contents toequilibrate an additional 10 min and draw the level downexactly to the calibration line, avoiding parallax and using amagnifier,
41、if necessary, to obtain good visibility. Remove anyliquid adhering to the walls above the calibration mark, withthe draw-off needle or pipe cleaner, depending upon thevolatility of the sample. Portions in the overflow bulb can beremoved with a cotton swab moistened with acetone.NOTE 4For temperature
42、s above 80C calculate the volume from thecoefficient of expansion of the glass observed from calibrations made at60, 70, and 80C.9.4 Replace the glass stopper, remove the pycnometer fromthe bath, wash the outside surface with acetone, and drythoroughly with a chemically clean, lint-free, slightly da
43、mpcloth. Place the pycnometer in or near the balance case for 20min and weigh to the nearest 0.1 mg.NOTE 5In atmospheres of low humidity (60 % or lower), drying thepycnometer by rubbing with a dry cotton cloth will induce static chargesequivalent to a loss of about 1 mg in the weight of the pycnomet
44、er. Thischarge may not be completely dissipated in less than 30 min. The use ofabout 0.1 mg of radium bromide- or polonium-coated foil in the balancecase, or maintaining the relative humidity at 60 percent or higher, aids inreducing weighing difficulties due to static charges.9.5 Calculate the pycno
45、meter calibration factor, Ft, from theequation:Ft5 density of water at tC!/ (1)weight of water in pycnometer at tC!See Table 2 for the density of water between 0 and 100C.9.6 Duplicate determinations should not show a variationgreater than 60.2 mg in the net weight of the water in thepycnometer.10.
46、Procedure for Viscous Liquids10.1 Weigh the pycnometer as directed in Section 8.10.2 Warm, in an oven or convenient warming chamber, thepycnometer, syringe with needle, and sample to a convenientworking temperature consistent with the fluidity and volatilityof sample. Draw the requisite amount of sa
47、mple into thesyringe and immediately fill the warmed pycnometer takingcare to avoid occluding air bubbles in the pycnometer bulb orcapillary. Continue the addition of sample, withdrawing thefilling needle gradually so that the tip remains immersed in thesample, until the sample has been added to a d
48、epth of 10 or 20mm in the expansion chamber above the capillary, dependingupon the amount of contraction expected.10.3 Immerse the pycnometer bulb in the constant-temperature bath. As the sample contracts continue sampleaddition before the level recedes into the capillary or until asufficient amount
49、 has been added to maintain the meniscusslightly above the calibration mark at the reference tempera-ture. Allow to equilibrate to reference temperature.TABLE 1 Vacuum Corrections to be Applied to DensitiesObserved in Air of Various DensitiesNOTE 1Interpolate linearly for intermediate sample densities.NOTE 2For air densities outside this table the vacuum correction shallbe calculated from the equation C=da1(FtWt), dabeing the densityof the air in the balance case in grams per millilitre. See Section 10 of TestMet
