ASTM D7961-22

Standard Practice for Calibrating U-tube Density Cells over Large Ranges of Temperature and Pressure

SIGNIFICANCE AND USE
5.1 This practice covers a series of methods offered to aid users in calibrating U-tube density meters to provide a measure of density and an associated expanded uncertainty. The reference density, as obtained from either an equation of state (EOS) or CRM has an uncertainty that arises from the uncertainty of the measurements of temperature, pressure, and also the chemical purity of the substance studied (origin) or for that matter of the certified reference material. This uncertainty results in an additional uncertainty for the density of these samples. Because the measurements made with U-tube density meters are not absolute, the uncertainty with which the instrument calibration is determined is directly related to the uncertainty of the density obtained.
SCOPE
1.1 This practice outlines procedures for the calibration of U-tube density cells. It is applicable to instruments capable of determining fluid density at temperatures in the range –10 °C to 200 °C and pressures from just greater than the saturation pressure to 140 MPa. The practice refers to density cells as they are utilized to make measurements of fluids primarily in the compressed-liquid state. Examples of substances for which the density can be determined with a calibrated U-tube density meter include: crude oils, gasoline and gasoline-oxygenate blends, diesel and jet fuels, hydraulic fluids, and lubricating oils.  
1.2 This practice specifies a procedure for the determination of the expanded uncertainty of the density measurement.  
1.3 This practice pertains to fluids with viscosities  
1.4 4 The values listed in SI units are regarded as the standard, unless otherwise stated. The SI unit for mass density is kilograms per cubic metre (kg·m-3) and can be given as grams per cubic centimetre (g·cm-3).  
1.5 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2022
• ICS: 17.060 - Measurement of volume, mass, density, viscosity
• ICS: 75.180.30 - Volumetric equipment and measurements
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.04.0D - Physical and Chemical Methods

Relations

• Refers: ASTM D7578-20 - Standard Guide for Calibration Requirements for Elemental Analysis of Petroleum Products and Lubricants
• Effective Date: 01-May-2020
• Refers: ASTM D7740-20 - Standard Practice for Optimization, Calibration, and Validation of Atomic Absorption Spectrometry for Metal Analysis of Petroleum Products and Lubricants
• Effective Date: 01-Jul-2020

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D7961 − 22
Standard Practice for
Calibrating U-tube Density Cells over Large Ranges of
1
Temperature and Pressure
This standard is issued under the fixed designation D7961; 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* 2. Referenced Documents
2
2.1 ASTM Standards:
1.1 This practice outlines procedures for the calibration of
U-tube density cells. It is applicable to instruments capable of D1193 Specification for Reagent Water
D4052 Test Method for Density, Relative Density, and API
determining fluid density at temperatures in the range –10 °C
to 200 °C and pressures from just greater than the saturation Gravity of Liquids by Digital Density Meter
D4175 Terminology Relating to Petroleum Products, Liquid
pressure to 140 MPa. The practice refers to density cells as
they are utilized to make measurements of fluids primarily in Fuels, and Lubricants
D5002 Test Method for Density, Relative Density, and API
the compressed-liquid state. Examples of substances for which
the density can be determined with a calibrated U-tube density Gravity of Crude Oils by Digital Density Analyzer
D6792 Practice for Quality Management Systems in Petro-
meter include: crude oils, gasoline and gasoline-oxygenate
blends, diesel and jet fuels, hydraulic fluids, and lubricating leum Products, Liquid Fuels, and Lubricants Testing
Laboratories
oils.
D7483 TestMethodforDeterminationofDynamicViscosity
1.2 This practice specifies a procedure for the determination
and Derived Kinematic Viscosity of Liquids by Oscillat-
of the expanded uncertainty of the density measurement.
ing Piston Viscometer
1.3 This practice pertains to fluids with viscosities < 1 Pa·s
D7578 Guide for Calibration Requirements for Elemental
(1000 centipoise) at ambient conditions.
Analysis of Petroleum Products and Lubricants
D7740 Practice for Optimization, Calibration, and Valida-
1.4 4 The values listed in SI units are regarded as the
tion ofAtomicAbsorption Spectrometry for MetalAnaly-
standard, unless otherwise stated. The SI unit for mass density
-3
sis of Petroleum Products and Lubricants
is kilograms per cubic metre (kg·m ) and can be given as
-3
grams per cubic centimetre (g·cm ).
3. Terminology
1.5 This standard does not purport to address all of the
3.1 Definitions:
safety concerns, if any, associated with its use. It is the
3.1.1 For definitions of terms used in this practice, refer to
responsibility of the user of this standard to establish appro-
Terminology D4175.
priate safety, health, and environmental practices and deter-
3.1.2 calibration, n—set of operations that establishes the
mine the applicability of regulatory limitations prior to use.
relationship between the reference density of standards and the
1.6 This international standard was developed in accor-
corresponding density reading of the instrument. D4052
dance with internationally recognized principles on standard-
3.1.3 certified reference material (CRM), n—reference ma-
ization established in the Decision on Principles for the
terial one or more of whose property values are certified by a
Development of International Standards, Guides and Recom-
technically valid procedure, accompanied by a traceable cer-
mendations issued by the World Trade Organization Technical
tificate or other documentation that is issued by a certifying
Barriers to Trade (TBT) Committee.
body. [D02.94] D6792, [D02.03] D7578
3.1.4 density (ρ), n—mass per unit volume at a specified
temperature. [D02.07] D7483
1
This practice is under the jurisdiction ofASTM Committee D02 on Petroleum
Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcom-
2
mittee D02.04.0D on Physical and Chemical Methods. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Nov. 1, 2022. Published December 2022. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 2015. Last previous edition approved in 2017 as D7961 – 17. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D7961-22. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7961 − 22
3.1.5 standard reference material (SRM), n—trademark for 7. Reagents
reference
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it 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 version
of the standard as published by ASTM is to be considered the official document.
Designation: D7961 − 17 D7961 − 22
Standard Practice for
Calibrating U-tube Density Cells over Large Ranges of
1
Temperature and Pressure
This standard is issued under the fixed designation D7961; 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*
1.1 This practice outlines procedures for the calibration of U-tube density cells. It is applicable to instruments capable of
determining fluid density at temperatures in the range –10 °C to 200 °C and pressures from just greater than the saturation pressure
to 140 MPa. The practice refers to density cells as they are utilized to make measurements of fluids primarily in the
compressed-liquid state. Examples of substances for which the density can be determined with a calibrated U-tube density meter
include: crude oils, gasoline and gasoline-oxygenate blends, diesel and jet fuels, hydraulic fluids, and lubricating oils.
1.2 This practice specifies a procedure for the determination of the expanded uncertainty of the density measurement.
1.3 This practice pertains to fluids with viscosities < 1 Pa·s (1000 centipoise) at ambient conditions.
1.4 4 The values listed in SI units are regarded as the standard, unless otherwise stated. The SI unit for mass density is kilograms
-3 -3
per cubic metre (kg·m ) and can be given as grams per cubic centimetre (g·cm ).
1.5 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 appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2
2.1 ASTM Standards:
D1193 Specification for Reagent Water
D4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density Meter
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
D5002 Test Method for Density, Relative Density, and API Gravity of Crude Oils by Digital Density Analyzer
D6792 Practice for Quality Management Systems in Petroleum Products, Liquid Fuels, and Lubricants Testing Laboratories
D7483 Test Method for Determination of Dynamic Viscosity and Derived Kinematic Viscosity of Liquids by Oscillating Piston
Viscometer
1
This practice is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.04.0D on Physical and Chemical Methods.
Current edition approved Jan. 1, 2017Nov. 1, 2022. Published January 2017December 2022. Originally approved in 2015. Last previous edition approved in 20152017
as D7961 – 15.D7961 – 17. DOI: 10.1520/D7961-17.10.1520/D7961-22.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. 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
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7961 − 22
D7578 Guide for Calibration Requirements for Elemental Analysis of Petroleum Products and Lubricants
D7740 Practice for Optimization, Calibration, and Validation of Atomic Absorption Spectrometry for Metal Analysis of
Petroleum Products and Lubricants
3. Terminology
3.1 Definitions:
3.1.1 For definitions of terms used in this practice, refer to Terminology D4175.
3.1.2 calibration, n—set of operations that establishes the relationship between the reference density of standards and the
corresponding density reading of the instrument. D4052
3.1.3 certified reference material (CRM), n—reference material one or more of whose property values are certified by a technically
valid procedure, accompanied by a traceable certificate or other documentation that is issued by a certifying body. [D02.
...