ASTM D1267-2018 Standard Test Method for Gauge Vapor Pressure of Liquefied Petroleum (LP) Gases (LP-Gas Method).pdf

1、Designation: D1267 12D1267 18Standard Test Method forGageGauge Vapor Pressure of Liquefied Petroleum (LP)Gases (LP-Gas Method)1This standard is issued under the fixed designation D1267; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio

2、n, 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. Scope*1.1 This test method covers the determination of the gagegauge vapor pressures of liquefied petroleum gas

3、products(WarningFlammable gas. Harmful when inhaled.) at temperatures of 37.8C (100F)37.8 C (100 F) up to and including a testtemperature of 70C (158F).70 C (158 F). (WarningExtremely flammable gas. May be harmful when inhaled.)NOTE 1An alternative method for measurement of vapor pressure of liquefi

4、ed petroleum gases is Test Method D6897.1.2 The values stated in SI units are to be regarded as the standard.The values given in parentheses are for information only.afterSI units are provided for information only and are not considered standard.1.3 This standard does not purport to address all of t

5、he safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. For specific warning statements, see 1.1

6、and Annex A2.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical B

7、arriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D323 Test Method for Vapor Pressure of Petroleum Products (Reid Method)D1265 Practice for Sampling Liquefied Petroleum (LP) Gases, Manual MethodD6897 Test Method for Vapor Pressure of Liquefied Petroleum Gases (LPG) (Expansi

8、on Method)3. Terminology3.1 Definitions:3.1.1 liquefied petroleum gases, gas (LP gas, LPG), na narrow boiling range hydrocarbon mixtures consisting mainly ofpropane or propylene, or both, and butanes or butylenes, or both, plusmixture of hydrocarbons consisting of propane, propylene,butanes, and but

9、ylenes, individually or in specified combinations, with limited amounts of other hydrocarbons (such as ethane) andnaturally occurring occurring, petroleum-derived non-hydrocarbons.3.1.2 vapor pressure, nthe pressure exerted by the vapor of a liquid when in equilibrium with the liquid.4. Summary of T

10、est Method4.1 The test apparatus, consisting of two interconnected chambers and equipped with a suitable pressure gage,gauge, is purgedwith a portion of the sample which is then discarded. The apparatus is then filled completely with the portion of the sample to betested. Thirty-three and one-third

11、to forty volume percent of the sample content of the apparatus is immediately withdrawn toprovide adequate free space for product expansion. The apparatus is then immersed in a water bath maintained at the standard testtemperature of 37.8C (100F)37.8 C (100 F) or, optionally, at some higher test tem

12、perature up to and including a testtemperature of 70C (158F).70 C (158 F).1 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.H0 on Liquefied Petroleum Gas.Current edition

13、approved Nov. 1, 2012July 1, 2018. Published February 2013August 2018. Originally approved in 1953. Last previous edition approved in 20072012 asD126702(2007).D1267 12. DOI: 10.1520/D1267-12.10.1520/D1267-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer

14、 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 of what changes have been made to the pr

15、evious 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 considered the official document.*A Summary of C

16、hanges section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 The observed gagegauge pressure at equilibrium, after correcting for gagegauge error and correcting to a standardbarometric pressure

17、, is reported as the LPG Vapor Pressure at the selected test temperature.5. Significance and Use5.1 Information on the vapor pressures of liquefied petroleum gas products under temperature conditions from 37.837.8 C to70C (10070 C (100 F to 158F)158 F) is pertinent to selection of properly designed

18、storage vessels, shipping containers, andcustomer utilization equipment to ensure safe handling of these products.5.2 Determination of the vapor pressure of liquefied petroleum gas is important for safety reasons to ensure that the maximumoperating design pressures of storage, handling, and fuel sys

19、tems will not be exceeded under normal operating temperatureconditions.5.3 For liquefied petroleum gases, vapor pressure is an indirect measure of the most extreme low temperature conditions underwhich initial vaporization can be expected to occur. It can be can be considered a semi-quantitative mea

20、sure of the amount of themost volatile material present in the product.product, and this can give an indication of low temperature operability.6. Apparatus6.1 Vapor Pressure Apparatus, constructed as illustrated in Fig. A1.1, and the various items of auxiliary equipment,equipmentare completely descr

21、ibed in Annex A1.6.2 The vapor chamber of Test Method D323, can be interchangeable with the upper chamber of this method. Similarly, theliquid chamber (two-opening type) of Test Method D323 is interchangeable with the B, 20 % lower chamber in A1.1.4 of thismethod. Because of this interchangeability,

22、 the apparatus assembly of Test Method D323 shall pass, as a safety precaution, thehydrostatic test specified in A1.1.6 before using it in testing liquefied petroleum gas.6.3 Water Bath, temperature controlled, of a size suitable for the vapor pressure apparatus. See A1.3.6.4 Temperature Measuring D

23、evice, of verified accuracy and capable of monitoring the desired test temperature in the waterbath in the range of 3535 C to 70C70 C to within 60.1C.60.1 C.6.5 BarometerA pressure measuring device capable of measuring local station pressure with an accuracy of 0.1 kPa (1 mmHg) or better, at the sam

24、e elevation relative to sea level as the apparatus in the laboratory. (WarningDo not take readings fromordinary aneroid barometers, such as those used at weather stations and airports, since these are pre-corrected to give sea levelreadings.)7. Sampling and Sample Handling7.1 Samples shall be obtain

25、ed and stored in accordance with Practice D1265 unless the test samples can be taken directly fromthe source of the material to be tested.7.2 Any method of coupling the vapor pressure apparatus to the sample source may be employed. Tubing, 66 mm to 7 mm (14in.) in diameter, of minimum length, of sui

26、table-working suitable working pressure, and made of material corrosion-resistant tothe products being sampled, is satisfactory for this purpose. A flexible tubing connection of a satisfactory type greatly facilitatesthe purging and sampling operations. The tubing should be a conducting material or

27、constructed with a built-in ground connectionto minimize the effect of static electricity.8. Preparation of Apparatus8.1 If the apparatus has been used for testing products other than the type of product to be tested, disassemble, clean thoroughly,and purge the parts in a stream of dry air.8.2 Assem

28、ble the apparatus with the inlet valve of the lower chamber open, the straight-through valve between the twochambers open, the bleeder valve closed, and with the proper range pressure gagegauge attached.9. Procedure9.1 Safe means for the disposal of vapors and liquids during this operation and in th

29、e subsequent sampling operation shall beprovided.9.2 PurgingWith the assembled apparatus in an upright position, connect the inlet valve of the lower chamber to the samplesource with the sampling connection (7.2). Open the sample source valve to the apparatus. Cautiously open the bleeder valve onthe

30、 upper chamber, permitting the air or vapors, or both, in the apparatus to escape until the apparatus is full of liquid. Close thelower chamber inlet valve and open the bleeder valve to its wide open wide-open position.Allow the contained liquid to evaporateuntil the apparatus is covered with white

31、frost (may require more than one chilling), then invert the assembly, and expel anyresidual material through the bleeder valve. Allow the residual vapors to escape until the pressure in the apparatus is essentiallyatmospheric, then close the bleeder valve.D1267 1829.3 SamplingReturn the apparatus, n

32、ow containing only vapors, to its normal upright position and open the inlet valve. Assoon as the apparatus attains essentially the same pressure as the pressure of the sample source, momentarily open the bleedervalve. If liquid does not promptly emerge, repeat the purging step (9.2). If liquid appe

33、ars immediately, close the bleeder and inletvalves in that order (Note 12). Close the valve on the sample source, and disconnect the sampling line. Immediately close thestraight-through valve between the two chambers and open the inlet valve, with the apparatus in an upright position. Close the inle

34、tvalve as soon as no more liquid escapes, and immediately open the straight-through valve.NOTE 2Transfer of the sample is facilitated by chilling the apparatus with a portion of the material under test.9.3.1 When using the 3313 % lower chamber (A1.1.3), proceed to 9.4.9.3.2 When using the 20 % lower

35、 chamber (Appendix (A1.1.4), close the straight-through valve and again open the inlet topermit expulsion of the lower chamber contents. As soon as no more liquid escapes from the lower chamber, close the inlet valveand immediately open the straight-through valve.9.3.3 The upper chamber, prior to th

36、is operation, is liquid full at some temperature that is normally below the environmentaltemperature. Since any warming of the apparatus would cause expansion of the liquid content of the upper chamber, leading topossible rupture of the chamber, it is necessary that the procedural steps of providing

37、 free space in the apparatus be completedpromptly.9.4 Vapor Pressure Determination:9.4.1 Invert the apparatus and shake it vigorously. Return the apparatus to its normal upright position and immerse it in theconstant-temperature water bath maintained at the test temperature (4.1). The apparatus incl

38、uding the bleeder valve coupling, butnot the pressure gage,gauge, must be immersed. Throughout the determination, the temperature of the water bath shall be checkedperiodically by means of the temperature measuring device.9.4.1.1 At test temperatures from 37.8C (100F)37.8 C (100 F) up to and includi

39、ng 50C (122F),50 C (122 F), maintainthe bath at 60.1C (0.2F).60.1 C (0.2 F). At test temperatures above 50C (122F),50 C (122 F), up to and including 70C(158F),70 C (158 F), maintain the bath at 60.3C (0.5F).60.3 C (0.5 F).9.4.1.2 Observe the apparatus assembly throughout the test period to ensure fr

40、eedom from leaks. Discontinue the test anddiscard the results at any time a leak is detected.9.4.2 After 5 min have elapsed, withdraw the apparatus from the water bath, invert it, shake it vigorously, and then return it tothe bath. Perform the shaking operation quickly to avoid excessive cooling of

41、the apparatus and its contents. Thereafter, at intervalsof not less than 2 min, withdraw the apparatus from the bath, invert, shake it vigorously, and then return it to the bath. Prior toeach removal of the apparatus from the water bath, tap the gagegauge lightly and observe the pressure reading. Th

42、ese operationswill normally require 2020 min to 30 min to ensure equilibrium. After this time, if consecutive observed gagegauge readings areconstant, record the pressure reading as the Uncorrected LP-Gas Vapor Pressure of the sample at the test temperature.9.4.3 If a pressure gagegauge is used that

43、 is not calibrated against a dead-weight tester, it is necessary to determine if agagegauge correction needs to be applied to the pressure gagegauge reading. Without removing the pressure gagegauge from theapparatus or the apparatus from the bath, attach a test gage,gauge, previously calibrated agai

44、nst a dead-weight tester, to the bleedervalve outlet and open the bleeder valve.At the end of 5 min, compare the readings of the two gages.gauges. Record any correctionthus determined as gagegauge correction.9.4.3.1 Alternatively, if a pressure gagegauge is used that has been calibrated against a de

45、ad-weight tester, then the gagegaugecorrection is zero and it is not necessary to determine a gagegauge correction as per 9.4.3, using a second test gagegauge that hasbeen calibrated against a dead-weight tester.10. Calculation10.1 Correct the Uncorrected LP-Gas Vapor Pressure for gagegauge errors (

46、see 9.4.3 and 9.4.3.1).10.2 Convert the corrected vapor pressure = (test gage reading) + (gagegauge reading) + (gauge correction) as calculated in9.4.3 to a standard barometric pressure of 760 mm (29.92 in.) Hg by means of the following equation:10.2.1 LP-Gas Vapor Pressure:5corrected vapor pressure

47、,kPa27602P1!0.1333 (1)5corrected vapor pressure,psi27602P1!0.0193 (2)where:P1 = observed barometric pressure, mm Hg.10.2.2 LP-Gas Vapor Pressure:5corrected vapor pressure,kPa229.922P2!3.3864 (3)5corrected vapor pressure,psi229.922P2!0.4912 (4)where:P2 = observed barometric pressure, in. Hg.D1267 183

48、10.2.3 Conversion Factors:1kPa57.50064 mmHg50.295301 in. Hg (5)1psi551.7151 mmHg52.03603 in. Hg (6)11. Report11.1 Report the LP-Gas vapor pressure test results in terms of kilopascals to the nearest 5 kPa or pounds per square inch, tothe nearest 0.5 psi gage,gauge, the test temperature, and referenc

49、e this test method.12. Precision and Bias12.1 The following shall be used as a basis for judging the acceptability of results (95 % probability).12.1.1 RepeatabilityThe difference between two test results, obtained by the same operator with the same apparatus underconstant operating conditions on identical test materials would, in the normal and correct operation of the test method, exceed thefollowing value only in one case in twenty:20:12 kPa 1.8 psi! (7)12.1.2 ReproducibilityThe difference between two sin