1、Designation: D4052 11D4052 15Standard Test Method forDensity, Relative Density, and API Gravity of Liquids byDigital Density Meter1This standard is issued under the fixed designation D4052; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This test me
3、thod covers the determination of the density, relative density, and API Gravity of petroleum distillates andviscous oils that can be handled in a normal fashion as liquids at the temperature of test, utilizing either manual or automatedsample injection equipment. Its application is restricted to liq
4、uids with total vapor pressures (see Test Method D5191) typicallybelow 100 kPa 100 kPa and viscosities (see Test Method D445 or D7042) typically below about 15 000 mm15 000 mm2/s at thetemperature of test. The total vapor pressure limitation however can be extended to 100 kPa 100 kPa provided that i
5、t is firstascertained that no bubbles form in the U-shaped, oscillating tube, which can affect the density determination. Some examples ofproducts that may be tested by this procedure include: gasoline and gasoline-oxygenate blends, diesel, jet, basestocks, waxes, andlubricating oils.1.1.1 Waxes and
6、 highly viscous samples were not included in the 1999 interlaboratory study (ILS) sample set that was used todetermine the current precision statements of the method, since all samples evaluated at the time were analyzed at a testtemperature of 15C.15 C. Wax and highly viscous samples require a temp
7、erature cell operated at elevated temperatures necessaryto ensure a liquid test specimen is introduced for analysis. Consult instrument manufacturer instructions for appropriate guidanceand precautions when attempting to analyze wax or highly viscous samples. Refer to the Precision and Bias section
8、of the methodand Note 8 for more detailed information about the 1999 ILS that was conducted.1.2 In cases of dispute, the referee method is the one where samples are introduced manually as in 6.3 or 6.4, as appropriatefor sample type.1.3 This test method should not be applied to samples so dark in co
9、lor that the absence of air bubbles in the sample cell cannotbe established with certainty. For the determination of density in crude oil samples use Test Method D5002.1.4 The values stated in SI units are regarded as the standard, unless stated otherwise, such as the “torr” units of pressure inothe
10、rwise. Eq 1. The accepted units of measure for density are grams per millilitre (g/mL) or kilograms per cubic metre (kg/m3).1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish app
11、ropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For specific warning statements, see 7.4, 7.5, and 10.3.2. Referenced Documents2.1 ASTM Standards:2D287 Test Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method
12、)D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)D1193 Specification for Reagent WaterD1250 Guide for Use of the Petroleum Measurement TablesD1298 Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid
13、Petroleum Products byHydrometer MethodD4057 Practice for Manual Sampling of Petroleum and Petroleum Products1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.04.0D on Phy
14、sical and Chemical Methods.Current edition approved Oct. 15, 2011Dec. 15, 2015. Published December 2011February 2016. Originally approved in 1981. Last previous edition approved in 20092011as D4052D4052 11.09. DOI: 10.1520/D4052-11.10.1520/D4052-15.2 For referencedASTM standards, visit theASTM websi
15、te, 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 not an ASTM standard and is intended only to provide the user of an ASTM standard an indication
16、 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 appropriate. In all cases only the current versionof the standard as published by ASTM is to be conside
17、red 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 States1D4177 Practice for Automatic Sampling of Petroleum and Petroleum ProductsD4377 Test Method for
18、Water in Crude Oils by Potentiometric Karl Fischer TitrationD5002 Test Method for Density and Relative Density of Crude Oils by Digital Density AnalyzerD5191 Test Method for Vapor Pressure of Petroleum Products (Mini Method)D7042 Test Method for Dynamic Viscosity and Density of Liquids by Stabinger
19、Viscometer (and the Calculation of KinematicViscosity)3. Terminology3.1 Definitions:3.1.1 density, nmass per unit volume at a specified temperature.3.1.2 relative density, nthe ratio of the density of a material at a stated temperature to the density of water at a statedtemperature.3.2 Definitions o
20、f Terms Specific to This Standard:3.2.1 adjustment, vthe operation of bringing the instrument to a state of performance suitable for its use, by setting oradjusting the density meter constants.3.2.1.1 DiscussionOn some digital density analyzer instruments, an adjustment may be made rather than calib
21、rating the instrument. The adjustmentprocedure uses air and redistilled, freshly boiled reagent water (WarningHandling water at boiling or near boiling temperaturecan present a safety hazard. Wear appropriate personal protective equipment.) as standards to establish the linearity ofmeasurements over
22、 a range of operating temperatures.3.2.2 calibration, vset of operations that establishes the relationship between the reference density of standards and thecorresponding density reading of the instrument.4. Summary of Test Method4.1 A small volume (approximately 1 to 2 mL) volume, approximately 1 m
23、L to 2 mL, of liquid sample is introduced into anoscillating sample tube and the change in oscillating frequency caused by the change in the mass of the tube is used in conjunctionwith calibration data to determine the density, relative density, orAPI Gravity of the sample. Both manual and automated
24、 injectiontechniques are described.5. Significance and Use5.1 Density is a fundamental physical property that can be used in conjunction with other properties to characterize both thelight and heavy fractions of petroleum and petroleum products.5.2 Determination of the density or relative density of
25、 petroleum and its products is necessary for the conversion of measuredvolumes to volumes at the standard temperature of 15C.15 C.6. Apparatus6.1 Digital Density AnalyzerA digital analyzer consisting of a U-shaped, oscillating sample tube and a system for electronicexcitation, frequency counting, an
26、d display. The analyzer shall accommodate the accurate measurement of the sample temperatureduring measurement or shall control the sample temperature as described in 6.2. The instrument shall be capable of meeting theprecision requirements described in this test method.6.2 Circulating Constant-Temp
27、erature Bath, (optional), capable of maintaining the temperature of the circulating liquid constantto 60.05C60.05 C in the desired range. Temperature control can be maintained as part of the density analyzer instrumentpackage.6.3 Syringes, for use primarily in manual injections, at least 2 mL 2 mL i
28、n volume with a tip or an adapter tip that will fit theopening of the oscillating tube.6.4 Flow-Through or Pressure Adapter, for use as an alternative means of introducing the sample into the density analyzer eitherby a pump, by pressure, or by vacuum.NOTE 1It is highly recommended that a vacuum not
29、 be applied to samples prone to light-end loss, as it can easily lead to the formation of bubbles.It is recommended to fabricate a special cap or stopper for sample containers so that air, such as from a squeeze pump, is used to displace a test specimento the U-tube measuring cell by the flow-throug
30、h method.6.5 Autosampler, required for use in automated injection analyses. The autosampler shall be designed to ensure the integrity ofthe test specimen prior to and during the analysis and be equipped to transfer a representative portion of test specimen to the digitaldensity analyzer.D4052 1526.6
31、 Temperature Sensing Device (TSD), capable of monitoring the observed test temperature to within an accuracy of6 0.05C.6 0.05 C. If a liquid-in-glass thermometer is used as the TSD, it shall be calibrated and graduated to 0.1C,0.1 C, andhave a holder that can be attached to the instrument for settin
32、g and observing the test temperature. In calibrating the thermometer,the ice point and bore connections should be estimated to the nearest 0.05C.0.05 C. For non-mercurial thermometers, the TSDdevice shall be calibrated at least annually against a certified and traceable standard.6.7 Ultrasonic Bath,
33、 Unheated, (optional), of suitable dimensions to hold container(s) placed inside of bath, for use ineffectively dissipating and removing air or gas bubbles that may be entrained in viscous sample types prior to analysis.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall be
34、used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, wheresuch specifications are available.3 Other grades may be used, provided it is first ascertained that the re
35、agent is of sufficiently highpurity to permit its use without lessening the accuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean reagent water as defined byType II of Specification D1193 or higher.7.3 Water, redistilled, reagent
36、 water, freshly boiled (toWarningHandling water at boiling or near boiling temperature canpresent a safety hazard. Wear appropriate personal protective equipment.) reagent water for use as a remove dissolved gasses, foruse as primary calibration standard. (WarningHandling water at boiling or near bo
37、iling temperature can present a safety hazard.Wear appropriate personal protective equipment.)7.4 Cleaning Solvent, such as petroleum naphtha4 (WarningPetroleum naphtha is extremely flammable), or other materialsthat are capable of flushing and removing samples entirely from the sample tube.7.5 Acet
38、one, for flushing and drying the sample tube. (WarningExtremely flammable.)7.6 Dry Air, for drying the oscillator tube.8. Sampling, Test Specimens, and Test Units8.1 Sampling is defined as all the steps required to obtain an aliquot of the contents of any pipe, tank, or other system, and toplace the
39、 sample into the laboratory test container. The laboratory test container and sample volume shall be of sufficient capacityto mix the sample and obtain a homogeneous sample for analysis.8.2 Laboratory SampleUse only representative samples obtained as specified in Practices D4057 or D4177 for this te
40、stmethod.8.3 Test SpecimenA portion or volume of sample obtained from the laboratory sample and delivered to the density analyzersample tube. The test specimen is obtained as follows:8.3.1 Mix the sample if required to homogenize taking care to avoid the introduction of air bubbles. The mixing may b
41、eaccomplished as described in Practice D4177 or Test Method D4377. Mixing at room temperature in an open container can resultin the loss of volatile material from certain sample types (for example, gasoline samples), so mixing in closed, pressurizedcontainers or at least 10C10 C below ambient temper
42、ature is required for such sample types where loss of volatile material isa potential concern. For some sample types, such as viscous lube oils that are prone to having entrained air or gas bubbles presentin the sample, the use of an ultrasonic bath (see 6.7) without the heater turned on (if so equi
43、pped), has been found effective indissipating bubbles typically within 10 min.10 min.NOTE 2When mixing samples with volatile components, consider the sample properties in relation to both ambient temperature and pressure.8.3.2 For manual injections, draw the test specimen from a properly mixed labor
44、atory sample using an appropriate syringe. Ifthe proper density analyzer attachments and connecting tubes are used, as described in 6.4, then the test specimen can be delivereddirectly to the analyzers sample tube from the mixing container. For automated injections, it is necessary to first transfer
45、 a portionof sample by appropriate means from a properly mixed laboratory sample to the autosampler vials, and take the necessary stepsto ensure the integrity of the test specimen prior to and during the analysis. Sample vials for the autosampler shall be sealedimmediately after filling up to 8080 %
46、 6 5%5 % and shall be kept closed until the auto sampler transfers the test specimen intothe measuring cell. For highly volatile samples, cool the sample prior to measurement. Follow the manufacturers instructions.NOTE 3Overfilled sample vials can result in cross-contamination between sample vials.3
47、 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmaco
48、peia and NationalFormulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville, MD.4 Suitable solvent naphthas are marketed under various designations such as “Petroleum Ether,” “Ligroine,” or “Precipitation Naphtha.”D4052 1539. Preparation of Apparatus9.1 Set up the density analyzer (including
49、the constant temperature bath and related attachments, if necessary) following themanufacturers instructions. Adjust the bath or internal temperature control so that the desired test temperature is established andmaintained in the sample compartment of the analyzer. Calibrate the instrument at the same temperature at which the density orrelative density of the sample is to be measured or perform an adjustment (see 3.2.1Discussion) in preparation of analyzingsamples. (WarningPrecise setting and control of the test temperature in the sample tu
