1、Designation: D1657 12 (Reapproved 2017)Manual of Petroleum Measurement Standards (MPMS), Chapter 9.2Standard Test Method forDensity or Relative Density of Light Hydrocarbons byPressure Hydrometer1This standard is issued under the fixed designation D1657; the number immediately following the designat
2、ion indicates the year oforiginal adoption or, in the case of 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. Scope1.1 This test method covers the determ
3、ination of the densityor relative density of light hydrocarbons including liquefiedpetroleum gases (LPG) having Reid vapor pressures exceeding101.325 kPa (14.696 psi).1.2 The prescribed apparatus should not be used for mate-rials having vapor pressures higher than 1.4 MPa (200 psi) atthe test temper
4、ature. This pressure limit is dictated by the typeof equipment. Higher pressures can apply to other equipmentdesigns.1.3 The initial pressure hydrometer readings obtained areuncorrected hydrometer readings and not density measure-ments. Readings are measured on a hydrometer at either thereference te
5、mperature or at another convenient temperature,and readings are corrected for the meniscus effect, the thermalglass expansion effect, alternate calibration temperature effectsand to the reference temperature by means of calculations andAdjunct to D1250 Guide for Petroleum Measurement Tables(API MPMS
6、 Chapter 11.1) or API MPMS Chapter 11.2.4 (GPATP-27), as applicable.1.4 Values determined as density or relative density can beconverted to equivalent values in the other units or alternativereference temperatures by means of Interconversion Proce-dures API MPMS Chapter 11.5, or Adjunct to D1250 Gui
7、de forPetroleum Measurement Tables (API MPMS Chapter 11.1) orAPI MPMS Chapter 11.2.4 (GPA TP-27), as applicable.1.5 The calculations required in Section 11 shall be appliedto the initial pressure hydrometer reading with observationsand results reported as required by Section 11 prior to use in asubs
8、equent calculation procedure (measurement ticketcalculation, meter factor calculation, or base prover volumedetermination).1.6 Annex A1 contains a procedure for verifying or certify-ing the equipment for this test method.1.7 The values in SI units are to be regarded as the standard.US Customary valu
9、es shown in adjacent parentheses are forinformation only and may not be exactly equivalent. Both SIand customary units have been rounded so that they may not beexactly equivalent.1.8 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is therespon
10、sibility 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.1.9 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established
11、in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1250 Guide for Use of the Petroleum Measurement TablesD1265 Practice
12、for Sampling Liquefied Petroleum (LP)Gases, Manual MethodD1298 Test Method for Density, Relative Density, and APIGravity of Crude Petroleum and Liquid Petroleum Prod-ucts by Hydrometer Method (API MPMS Chapter 9.1)E1 Specification for ASTM Liquid-in-Glass Thermometers1This test method is under the j
13、urisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and the API Committee onPetroleum Measurement, and is the direct responsibility of Subcommittee D02.02/COMQ, the joint ASTM-API Committee on Hydrocarbon Measurement forCustody Transfer (Joint ASTM-API). This test me
14、thod has been approved by thesponsoring committees and accepted by the Cooperating Societies in accordancewith established procedures.Current edition approved July 15, 2017. Published July 2017. Originallyapproved in 1939. Last previous edition approved in 2012 as D1657 12. DOI:10.1520/D1657-12R17.2
15、For 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. Jointly copyrighted by ASTM International, 100 Barr Harbor Dr
16、ive, PO Box C700, West Conshohocken, PA 19428-2959, USA and the American Petroleum Institute (API), 1220 L Street NW, Washington DC 20005, USAThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principle
17、s for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1E100 Specification for ASTM Hydrometers2.2 API Standards:3MPMS Chapter 9.1 Test Method for Density, RelativeDensity, and API Gravity of Crud
18、e Petroleum and LiquidPetroleum Products by Hydrometer Method (ASTM TestMethod D1298)MPMS Chapter 11.1 Temperature and Pressure Volume Cor-rection Factors for Generalized Crude Oils, Refined Prod-ucts and Lubricating Oils (Adjunct to ASTM D1250)MPMS Chapter 11.2.2 Compressibility Factors for Hydro-c
19、arbons: 0.350-0.0637 Relative Density (60F/60F) and-50F to 140F Metering TemperatureMPMS Chapter 11.2.2M Compressibility Factors for Hydro-carbons: 350-637 Kilograms per Cubic Meter Density15C and -46C to 60C Metering TemperaturesMPMSChapter 11.2.4 Temperature Correction for the Vol-ume of NGL and L
20、PG Tables 23E, 24E, 53E, 54E, 59Eand 60E (joint standard with GPA TP-27)MPMS Chapter 11.5 Density/Weight/Volume Intraconver-sion2.3 GPA Standards:4GPA Technical Publication TP-27 Temperature Correctionfor the Volume of NGL and LPG, Tables 23E, 24E, 53E,54E, 59E and 60E (joint standard with API MPMSC
21、hapter 11.2.4)2.4 ASTM Adjuncts:Adjunct to D1250 Guide for Petroleum Measurement Tables(API MPMS Chapter 11.1)53. Terminology3.1 Definitions:3.1.1 density, nthe mass of liquid per unit volume at 15 Cand its saturation pressure with the standard unit of measure-ment being kilograms per cubic metre.3.
22、1.1.1 DiscussionOther reference temperatures, such as20 C may be used for some products or in some locations.Less preferred units of measurement; for example, kg/L org/mL, are still in use.3.1.2 relative density (specific gravity), nthe ratio of themass of a given volume of liquid at a specific temp
23、erature tothe mass of an equal volume of pure water at the same ordifferent temperature. Both reference temperatures shall beexplicitly stated.3.1.2.1 DiscussionCommon reference temperatures in-clude 60/60 F, 20 20 C, 20/4 C. The historic deprecatedterm “specific gravity” may still be found.3.1.3 th
24、ermohydrometer, na glass hydrometer with a self-contained mercury thermometer.4. Summary of Test Method4.1 The apparatus is purged with a portion of the samplebefore filling with the portion to be used for testing. Thepressure cylinder is filled to a level at which the enclosedhydrometer floats free
25、ly, and the cylinder is then placed in aconstant-temperature bath (if needed). When the temperaturehas reached equilibrium, the hydrometer reading and thetemperature of the sample are read. The observed hydrometerreading is corrected for the meniscus effect, alternate calibra-tion temperature effect
26、s and reduced to the reference tempera-ture by means of the volume correction factors or tables asapplicable by use of the appropriate Adjunct to D1250 Guidefor Petroleum Measurement Tables (API MPMS Chapter 11.1)or API MPMS Chapter 11.2.4 (GPA TP-27), as applicable, andobserved temperature from the
27、 thermometer.5. Significance and Use5.1 The density or relative density of light hydrocarbons andliquefied petroleum gases is used in custody transfer quantitycalculations or to satisfy transportation, storage, and regulatoryrequirements.6. Apparatus6.1 Hydrometers, graduated in density with a range
28、 from500 kg m3to 650 kg m3, or in relative density with a rangefrom 0.500 to 0.650, and conforming to the dimensions inSpecification E100.6.1.1 Thermohydrometers, for field applications, thermohy-drometers may be more convenient than hydrometers withseparate thermometers. They shall conform to Speci
29、ficationE100, Thermohydrometer Nos. 101H or 310H.6.1.1.1 Thermohydrometers shall be of suitable range andhave dimensions to float freely within the pressure hydrometercylinder with clearances of 5 mm at the wall and 25 mm at thetop and bottom.6.1.1.2 The test report shall state that a thermohydromet
30、erwas used.6.1.1.3 The user should ascertain that the instruments usedfor this procedure conform to the requirements set out abovewith respect to materials, dimensions, and scale errors. In caseswhere the instrument is provided with a calibration certificateissued by a recognized standardizing body,
31、 the instrument isclassed as certified and the appropriate corrections for themeniscus effect, the thermal glass expansion effect, and alter-native calibration temperature effects shall be applied to theobserved readings prior to corrections. Instruments that satisfythe requirements of this test met
32、hod, but are not provided witha recognized calibration certificate, are classed as uncertifiedand the appropriate corrections for the meniscus effect, thethermal glass expansion effect, and alternative calibrationtemperature effects shall be applied to the observed readingsprior to corrections.6.2 H
33、ydrometer Cylinder, constructed of transparent plastic;for example, poly(methyl methacrylate) or equivalent material,conforming to the design and recommended dimensions givenin Fig. 1. The cylinder shall be of such dimensions that thehydrometer shall float freely within it. The ends shall be tightly
34、sealed with neoprene gaskets and metal end plates as shown inFig. 1.(WarningA protective shield shall be placed aroundthe cylinder. Replace any cylinders that show signs of fogging,crazing, cracking, or etching.)3Available from American Petroleum Institute (API), 1220 L. St., NW,Washington, DC 20005
35、-4070, http:/www.api.org.4Available from Gas Processors Association (GPA), 6526 E. 60th St., Tulsa, OK74145, http:/www.gpaglobal.org.5Available from ASTM International Headquarters. Order Adjunct No.ADJD1250. Original adjunct produced in 1983.D1657 12 (2017)2NOTE 1Certain compounds attack plastics a
36、nd cloud the inner surfaceof the cylinder, making it difficult or impossible to read the hydrometer.Tests showed no attack by ethane, ethene (ethylene), propane, propylene,butane, methylpropane (isobutane), butenes (normal butylenes), methyl-propene (isobutylene), pentane, and methylbutane (isopenta
37、ne), and noattack is expected from butadiene and acetaldehyde. Users are cautioned,however, to clean the cylinder thoroughly after each determination.Ketones and alcohols should not be used for cleaning as they attack andweaken plastics while aromatics also tend to attack the surface of plasticsand
38、should similarly not be used. A light aliphatic hydrocarbon isrecommended for cleaning. (WarningExtremely flammable. Harmful ifinhaled. Vapors may cause flash fire.)FIG. 1 Pressure Hydrometer CylinderD1657 12 (2017)36.2.1 The liquid inlet valve and the liquid outlet valve shallbe tightly connected t
39、o a base plate that shall be bored to giveboth valves a common inlet to the cylinder. The vapor ventvalve shall be similarly connected to the top plate, which shallbe bored to provide a vapor outlet from the pressure cylinder.All valves shall be 6 mm (14 in.) or equivalent needle valves.6.2.2 The cy
40、linder shall not be operated at a gage pressuregreater than 1.4 MPa (200 psi). A hydrostatic test at 2.8 MPa(400 psi) shall be carried out at intervals no greater than12 months.NOTE 2For SafetyThe cylinder should be equipped with appropri-ate safety devices to prevent over-pressure. Consideration sh
41、ould be givento pressure testing the cylinder at 1.25 to 1.5 times its normal maximumoperating pressure on a periodic basis, not to exceed two years.6.3 Thermometers, conforming to ASTM 12C or 12F inSpecification E1. The thermometer shall be held firmly insidethe hydrometer cylinder by a clip in suc
42、h a manner that it doesnot interfere with the free movement of the hydrometer.6.4 Constant-Temperature Bath, of dimensions such that itcan accommodate the hydrometer cylinder with the test portionfully immersed below the test portion liquid surface, and atemperature control system capable of maintai
43、ning the bathtemperature within 0.25 C of the test temperature throughoutthe duration of the test.7. Reference Liquids7.1 The following reference liquids are required for stan-dardization of the hydrometer:7.1.1 Propane, pure grade, having a nominal density of507.6 kg m3at 15 C or a relative density
44、 60/60 F of 0.50699.(WarningExtremely flammable. Harmful if inhaled. Vaporsmay cause flash fire.) The density of the reference liquid usedshall be known.7.1.2 Butane, pure grade, having a nominal density of584.1 kg m3at 15 C or a relative density 60/60 F of 0.5840.(WarningExtremely flammable. Harmfu
45、l if inhaled. Vaporsmay cause flash fire.) The density of the reference liquid usedshall be known.8. Sampling8.1 Unless otherwise specified, samples of liquid hydrocar-bons shall be obtained by the procedures described in PracticeD1265. The procedure for sampling for verification of theapparatus and
46、 for subsequent testing is described as follows.8.1.1 Connect the source of supply of the liquid to be testedto the inlet valve by suitable fittings so that a representativesample can be introduced into the cylinder.Ascertain that theseconnections are free of leaks. Open the outlet and vent valvesan
47、d purge the sampling connections by opening the inlet valveslightly, permitting the product to flow through the outlet valveat the bottom of the cylinder and the vent valve at the top of thecylinder.8.1.2 When the connections have been purged, close theoutlet and vent valves and open the inlet valve
48、, permitting theliquid to enter the cylinder until it is full. If necessary, the ventvalve may be opened slightly to permit complete filling of thecylinder after which it shall be closed. At no time shall thepressure in the cylinder be allowed to rise above a gagepressure of 1.4 MPa (200 psi).8.1.3
49、When the cylinder has been filled, close the inlet valveand open the outlet and vent valves, permitting the contents ofthe cylinder to be withdrawn completely and the pressureinside the cylinder to be returned to atmospheric pressure.8.1.4 Close the outlet and vent valves and open the inletvalve, filling the cylinder to a level at which the enclosedhydrometer floats freely. If it is necessary to accomplish thisfilling by venting vapor through the vent valve, repeat thepurging to cool the cylinder sufficiently to permit its beingfilled without ve
