Manual of Petroleum Measurement Standards Chapter 9.3

Standard Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method

THIRD EDITION, DECEMBER 2012

Manual of Petroleum Measurement Standards Chapter 9.3

Standard Test Method for Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method

Measurement Coordination

THIRD EDITION, DECEMBER 2012

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Foreword

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Contents

Page

1. Scope 1

2. Referenced Documents 1

3. Terminology 2

4. Summary of Test Method 2

5. Significance and Use 2

6. Apparatus 3

7. Sampling, Test Specimens, and Test Units 4

8. Apparatus Verification or Certification 4

9. Procedure 4

10. Calculation 7

11. Reports 9

12. Precision and Bias 9

13. Keywords 9

Annex A.1 (Mandatory Information) Apparatus 10

Summary of Changes 10

Figures

1. Typical Thermohydrometer Designs 3

2. Hydrometer Reading for Transparent Fluids 6

3. Hydrometer Reading for Opaque Fluids 7

Tables

1. Density Thermohydrometers 4

2. API Gravity Thermohydrometers 5

3. Limiting Conditions and Test Temperatures 5

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Designation: D6822 − 12b

Manual of Petroleum Measurement Standards (MPMS), Chapter 9.3

Standard Test Method for

Density, Relative Density, and API Gravity of Crude Petroleum and Liquid Petroleum Products by Thermohydrometer Method1

This standard is issued under the fixed designation D6822; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.

1. Scope*

   1. This test method covers the determination, using a glass thermohydrometer in conjunction with a series of calculations, of the density, relative density, or API gravity of crude petroleum, petroleum products, or mixtures of petroleum and nonpetroleum products normally handled as liquids and having a Reid vapor pressures of 101.325 kPa (14.696 psi) or less. Values are determined at existing temperatures and corrected to 15°C or 60°F by means of a series of calculations and international standard tables.

   2. The initial thermohydrometer readings obtained are uncorrected hydrometer readings and not density measure- ments. Readings are measured on a thermohydrometer at either the reference temperature or at another convenient temperature, and readings are corrected for the meniscus effect, the thermal glass expansion effect, alternate calibration tem- perature effects and to the reference temperature by means of calculations and Adjunct to D1250 Guide for Use of the Petroleum Measurement Tables (API MPMS Chapter 11.1).

   3. Readings determined as density, relative density, or API gravity can be converted to equivalent values in the other units or alternate reference temperatures by means of Interconver- sion Procedures (API MPMS Chapter 11.5) or Adjunct to D1250 Guide for Use of the Petroleum Measurement Tables (API MPMS Chapter 11.1), or both, or tables as applicable.

   4. The initial thermohydrometer reading shall be recorded before performing any calculations. The calculations required in Section 9 shall be applied to the initial thermohydrometer

      
      

      1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products and Lubricants and the API Committee on Petroleum Measurement, and is the direct responsibility of Subcommittee D02.02 /COMQ, the joint ASTM-API Committee on Hydrocarbon Measurement for Custody Transfer (Joint ASTM-API).

      Current edition approved June 1, 2012. Published October 2012. Originally approved in 2002. Last previous edition approved in 2012 as D6822-12a. DOI: 10.1520/D6822-12B.

      reading with observations and results reported as required by Section 11 prior to use in a subsequent calculation procedure (measurement ticket calculation, meter factor calculation, or base prover volume determination).

   5. Annex A1 contains a procedure for verifying or certify- ing the equipment of this test method.

   6. The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.

   7. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility 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.

      
      

2. Referenced Documents

   1. ASTM Standards:2

D1250 Guide for Use of the Petroleum Measurement Tables D1298 Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid Petroleum Prod-

ucts by Hydrometer Method

D4057 Practice for Manual Sampling of Petroleum and Petroleum Products

D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products

D5854 Practice for Mixing and Handling of Liquid Samples of Petroleum and Petroleum Products

D6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products and Lubricants

E100 Specification for ASTM Hydrometers

2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website.

*A Summary of Changes section appears at the end of this standard

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