ASTM D6897-03a
(Test Method)Standard Test Method for Vapor Pressure of Liquefied Petroleum Gases (LPG) (Expansion Method)
Standard Test Method for Vapor Pressure of Liquefied Petroleum Gases (LPG) (Expansion Method)
SIGNIFICANCE AND USE
Information on the vapor pressures of liquefied petroleum gas is pertinent to selection of properly designed storage vessels, shipping containers, and customer utilization equipment to ensure safe handling of these products.
Determination of the vapor pressure of liquefied petroleum gas is important for safety reasons to ensure that the maximum operating design pressures of storage, handling, and fuel systems will not be exceeded under normal operating temperature conditions.
For liquefied petroleum gases, vapor pressure can be considered a semi-quantitative measure of the amount of the most volatile material present in the product.
This test method uses a small sample volume and excludes any manual handling of a measuring chamber under high pressure.
SCOPE
1.1 This test method covers the use of automatic vapor pressure instruments to determine the vapor pressure of liquefied petroleum gas products at a temperature of 37.8°C, vapor to liquid ratio of 0.5:1, and pressures from 200 to 1550 kPa on a sample volume of 3.33 mL.
1.2 This test method is applicable to the determination of vapor pressures of liquefied petroleum gas products at temperatures from 37.8 to 70°C, vapor to liquid ratios of 0.1:1 to 4:1, and pressures up to 3500 kPa; however, the precision of the test method (see Section 15) has only been determined for a vapor to liquid ratio of 0.5:1, at a temperature of 37.8°C, and a pressure range from 300 to 1500 kPa.
Note 1—This test method is not intended to determine the true vapor pressure of LPG samples, but rather determine and report the vapor pressure of LPG at the 37.8°C temperature and 0.5:1 vapor to liquid ratio as the Test Method D 1267 method.
Note 2—This test method is not a true vapor pressure method and will not measure the full contribution from any dissolved gases such as nitrogen or helium if they are present. The contribution of light gases to the measured vapor pressure is highly dependent on the test temperature, type of gas, and V/L ratio of the test. A task group has been formed to determine or quantify the effect that the contribution of light gases have on the measured vapor pressure of LPG sample types as a function of the test temperature, type of gas, and V/L ratio of the test.
1.3 The values stated in SI units are to be regarded as standard.
1.4 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Appendix X2.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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An American National Standard
Designation: D 6897 – 03a
Standard Test Method for
Vapor Pressure of Liquefied Petroleum Gases (LPG)
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(Expansion Method)
This standard is issued under the fixed designation D 6897; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope* 2. Referenced Documents
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1.1 This test method covers the use of automatic vapor 2.1 ASTM Standards:
pressure instruments to determine the vapor pressure of lique- D 1265 Practice for Sampling Liquefied Petroleum (LP)
fied petroleum gas products at a temperature of 37.8°C, vapor Gases (Manual Method)
to liquid ratio of 0.5:1, and pressures from 200 to 1550 kPa on D 1267 Test Method for Gage Vapor Pressure of Liquefied
a sample volume of 3.33 mL. Petroleum (LP) Gases (LP-Gas Method)
1.2 This test method is applicable to the determination of D 2892 Test Method for Distillation of Crude Petroleum
vapor pressures of liquefied petroleum gas products at tem- (15-Theoretical Plate Column)
peratures from 37.8 to 70°C, vapor to liquid ratios of 0.1:1 to D 3700 Practice for Obtaining LPG Samples Using a Float-
4:1, and pressures up to 3500 kPa; however, the precision of ing Piston Cylinder
the test method (see Section 15) has only been determined for D 5191 Test Method for Vapor Pressure of Petroleum Prod-
a vapor to liquid ratio of 0.5:1, at a temperature of 37.8°C, and ucts (Mini Method)
a pressure range from 300 to 1500 kPa. D 6299 Practice for Applying Statistical Quality Assurance
Techniques to Evaluate Analytical Measurement System
NOTE 1—This test method is not intended to determine the true vapor
Performance
pressure of LPG samples, but rather determine and report the vapor
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2.2 Energy Institute Standards:
pressure of LPG at the 37.8°C temperature and 0.5:1 vapor to liquid ratio
as the Test Method D 1267 method. IP 181 Sampling Petroleum Gases
NOTE 2—This test method is not a true vapor pressure method and will
3. Terminology
not measure the full contribution from any dissolved gases such as
nitrogen or helium if they are present. The contribution of light gases to
3.1 Definitions:
the measured vapor pressure is highly dependent on the test temperature,
3.1.1 liquefied petroleum gases (LPG), n—narrow boiling
type of gas, and V/L ratio of the test. A task group has been formed to
range hydrocarbon mixtures, consisting mainly of propane or
determineorquantifytheeffectthatthecontributionoflightgaseshaveon
propylene,orboth(Warning—Extremelyflammable.Harmful
the measured vapor pressure of LPG sample types as a function of the test
if inhaled), butanes and butylenes, or both; in which the
temperature, type of gas, and V/L ratio of the test.
concentration of hydrocarbon compounds with boiling point
1.3 The values stated in SI units are to be regarded as
greater than 0°C is less than 5 % by liquid volume, and whose
standard.
vapor pressure at 37.8°C (100°F) is not greater than 1550 kPa.
1.4 This standard does not purport to address all of the
3.2 Definitions of Terms Specific to This Standard:
safety concerns, if any, associated with its use. It is the
3.2.1 total pressure (P ), n—the absolute pressure (relative
tot
responsibility of the user of this standard to establish appro-
to vacuum) exerted by the specimen at the specified tempera-
priate safety and health practices and determine the applica-
ture and vapor-liquid ratio.
bility of regulatory limitations prior to use. For specific
warning statements, see Appendix X2.
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For referenced ASTM standards, visit the ASTM website, www.astm.org, or
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This test method is under the jurisdiction of ASTM Committee D02 on contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee Standards volume information, refer to the standard’s Document Summary page on
D02.08 on Volatility. the ASTM website.
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Current edition approved Dec. 1, 2003. Published January 2004. Originally Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,
approved in 2003. Last previous edition approved in 2003 as D 6897–03. U.K.
*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.
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D 6897 – 03a
3.2.2 true vapor pressure, n—the physical property of a tion and expulsion. The piston and the valve combination shall
given liquid which specifies the maximum pressure at which a be at the same temperature as the measuring chamber to avoid
vapor phase
...
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