1、Designation: D1265 11 (Reapproved 2017)1Standard Practice forSampling Liquefied Petroleum (LP) Gases, Manual Method1This standard is issued under the fixed designation D1265; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 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.1NOTESI units formatting was corrected editorially in July 2017.1. Scope1.1 This practice covers equipment and procedures foro
3、btaining a representative sample of specification LiquefiedPetroleum Gas (LPG), such as specified in SpecificationD1835, GPA 2140, and comparable international standards.1.2 This practice is suitable for obtaining representativesamples for all routine tests for LP gases required by Specifi-cation D1
4、835. In the event of a dispute involving sampleintegrity when sampling for testing against SpecificationD1835 requirements, Practice D3700 shall be used as thereferee sampling procedure.1.3 This practice may also be used for other Natural GasLiquid (NGL) products that are normally single phase (NGLm
5、ix, field butane, etc.), defined in other industry specificationsor contractual agreements. It is not intended for non-specification products that contain significant quantities ofundissolved gases (N2,CO2), free water or other separatedphases, such as raw or unprocessed gas/liquids mixtures andrela
6、ted materials. The same equipment can be used for thesepurposes, but additional precautions are generally needed toobtain representative samples of multiphase products (seeAppendix X1 on Sampling Guidelines in Practice D3700).NOTE 1Practice D3700 describes a recommended practice for obtain-ing a rep
7、resentative sample of a light hydrocarbon fluid and the subse-quent preparation of that sample for laboratory analysis when dissolvedgases are present. Use of Practice D1265 will result in a small butpredictable low bias for dissolved gases due to the liquid ventingprocedure to establish the 20 % mi
8、nimum ullage.1.4 This practice includes recommendations for the locationof a sample point in a line or vessel. It is the responsibility ofthe user to ensure that the sampling point is located so as toobtain a representative sample.1.5 The values stated in SI units are to be regarded asstandard.1.5.1
9、 ExceptionNon-SI units are shown in parentheses forinformation only.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the a
10、pplica-bility of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued
11、 by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1835 Specification for Liquefied Petroleum (LP) GasesD3700 Practice for Obtaining LPG Samples Using a Float-ing Piston Cylinder2.2 Other Regulations:Canadian Transportation of Dang
12、erous Goods Regulations3GPA 2140 Gas Processors Association Liquefied PetroleumGas Specifications otherwise, determinations of mercaptans and hydro-gen sulfide, for example, can be misleading. Internal surfaces of samplecontainers and associated lines and fittings may be surface coated toreduce bare
13、 metal surfaces reacting with trace reactive components.6.1.6 Control hydrocarbon vapors vented during samplingto ensure compliance with applicable safety and environmentalregulations.7. Apparatus7.1 High Pressure Sample CylinderUse corrosion resis-tant metal sample containers certified by the autho
14、rity havingjurisdiction for pressure vessels with adequate pressure ratingfor the product being sampled. Suitable materials includestainless steel, Monel, and possibly other materials. Protectiveinternal coatings or surface treatments to render the internalsurface inert are acceptable. The size of t
15、he container dependsupon the amount of sample required for the laboratory tests tobe made. If the container is to be transported, it shall alsoconform to specifications published in transportation legisla-tion such as U.S. CFR 49 or Canadian Transportation ofDangerous Goods Regulations, and their su
16、pplements,reissues, or similar regulations in other jurisdictions.NOTE 3It has been common practice to refer to LPG samplecontainers as “sample bombs.” Use of this term is discouraged because ofobvious misunderstanding by many people. Alternate names such as“pressurized sample container” or “high pr
17、essure sample cylinder” arerecommended.NOTE 4DOT 3E cylinders are exempt from requalification in somejurisdictions. Other cylinders may need to be requalified according to localregulations.7.1.1 The sample container should be fitted with an internaloutage (ullage) tube to permit release of a minimum
18、 20 % ofthe container capacity as a liquid. The end of the containerfitted with the outage (ullage) tube shall be clearly marked.Typical sample containers are shown in Figs. 1 and 2.7.1.2 Sample containers without an internal outage (ullage)tubes are acceptable. Alternative purging and venting proce
19、-dures to obtain a minimum 20 % ullage in the container, asdescribed in 11.2.1, are required.7.1.3 Verify the high pressure sample cylinder and associ-ated valving for gas tightness by leak testing at a minimum of3450 kPa (500 psig) with inert gas prior to first use, wheneverpressure-containing comp
20、onents of the assembly are replaced,or otherwise on an annual basis.7.2 Sample Transfer Line made of stainless steel tubing orother flexible metal hose, impervious to the product beingsampled, is required. The most satisfactory line is one equippedwith two valves on the sample-container end, Fig. 1,
21、asampling valve, A, and a vent valve, B.PROCEDURE8. Purging Sample Transfer Line8.1 Connect the ends of the sample transfer line securely tothe product source and to Valve C (inlet) (Fig. 1)ofthecontainer. Close Valve A (sampling), Valve B (vent), and ValveC (inlet). Open the valve at the product so
22、urce and purge thetransfer line by opening Valve A (sampling) and Valve B (vent).9. Purging the Sample Container9.1 If the history of the sample container contents is notknown, or if traces of the previous product could affect theanalysis to be carried out, or both, use one of the following twopurge
23、 procedures:9.1.1 Ensure that Valve C (Fig. 2) and Valve D on the highpressure sample cylinder are closed. Connect a sample transferline (with closed Valves A and B) to the cylinder at Valve D andto the sample source. Maintain the cylinder in an uprightposition such that Valve C is at the top.D1265
24、11 (2017)129.1.2 Fill sample container by opening Valve A followed byValve C and Valve D until liquid issues from Valve C. At thattime, close Valve C, followed by Valve D and Valve A on thesample transfer line. Vent the sample transfer line by brieflyopening Valve B.9.1.3 Loosen the connection joini
25、ng the sample container tothe sample line and turn container through 180 such that ValveD is at the top. Open Valves C and D and drain out liquid.9.1.4 Return the sample container to position Valve C at thetop. Tighten connection to sample transfer line and repeat thepurging operation at least three
26、 times.9.2 In a flowing system or a suitable sample loop, thesample cylinder may be flushed online by connecting thedip-tube end of the cylinder to the higher pressure point, andthe other end back to the lower pressure point. Keep thecylinder upright with the dip tube end down to maintain liquidfill
27、ed during flushing. Flush the cylinder with at least 10 timesthe cylinder volume in a time of less than 5 min to ensure asufficient flow velocity to obtain turbulent mixing and flushingof the ullage volume area by using the dip tube as a venturimixer. The sample line shall be equipped with a suitabl
28、e flowindicator to ensure an adequate flow rate throughout theflushing period.9.2.1 This procedure is particularly applicable in areaswhere excessive venting of LPG to the atmosphere is notallowed.9.3 If the history of the sample container contents is knownand would not affect the analysis, use the
29、following purgeprocedure:9.3.1 With the container in an upright position, Fig. 1, andits Valve D (outlet) at the top, close Valve B (vent) and ValveC (inlet) and open Valve A (sampling). Open Valve C (inlet)and partly fill the container with sample by slowly opening theValve D (outlet). Close the Va
30、lve A (sampling) and allow partof the sample to escape in the vapor phase through Valve D(outlet). Close Valve D (outlet) and release the remainder of thesample in the liquid phase by opening Valve B (vent). Repeatthe purging operation at least three times.10. Transfer of Sample10.1 Position the sam
31、ple container securely in an uprightposition with Valve D (outlet) at the top (Fig. 1) and bothValves C and D closed.10.1.1 Close Valve B (vent), open Valve A (sampling), openValve C (inlet), and fill container with the sample. Close ValveC (inlet) and the valve at the product source. Open Valve BFI
32、G. 1 Typical Sample Container and Sampling ConnectionsD1265 11 (2017)13(vent). After the pressure is fully reduced, disconnect samplecontainer from the transfer line. Discard the sample if a leakdevelops or if either valve is opened during subsequenthandling of the sample container before performing
33、 the outage(ullage) operations outlined in Section 11.11. Sample Outage (Ullage)11.1 Immediately after obtaining the sample, place thecontainer in an upright position with the outage (ullage) tube atthe top.11.1.1 Open Valve D (outlet) slightly.Allow excess liquid toescape and close the valve at the
34、 first sign of vapor, as indicatedby the first “sputtering” and change in flow behavior of thevented liquid. If no liquid escapes, discard the sample and refillthe container.11.1.1.1 The cylinder shall not be stored/transported beyond80 % of its capacity with sample. Liquid sample shall bevented out
35、 to the required “reduced fill density” (typically80 % or less) prior to transport.NOTE 5Consult the authority having jurisdiction for LPG cylinderullage requirements for transport of LPG sample cylinders. Transportationlegislation such as U.S. CFR 49, Canadian Transportation of DangerousGoods Regul
36、ations, and IATA regulations limit the percent fill ofcontainers used for shipping LPG and may quote this requirement as areduced fill density or maximum fill density (normally 80 % maximumliquid fill at 15 C). A lower percent fill (lower fill density) may berequired if sampling at lower temperature
37、s.NOTE 6Extreme low temperature sampling. LPG has a larger coeffi-cient of thermal expansion than gasoline or distillate fuels. Sampling atextremely low ambient temperatures or from cryogenic sources mayrequire additional precautions to prevent sample cylinders from becomingliquid full (liquid locke
38、d, hydraulically locked) from warming the sampleto high ambient temperature.11.1.1.2 Where immediate venting is not possible, for ex-ample inside hazardous locations or with toxic materials(especially H2S), provisions shall be made to prevent tempera-ture increase prior to venting in a safe location
39、, transfer to alarger cylinder or immediate analysis or other disposition inaccordance with the authority having jurisdiction. It is theresponsibility of the user to establish safe procedures for use inpermitted facilities that are regulated by site permits orequivalent, separate from transportation
40、 regulations.NOTE 7Improperly venting LPG vapor to establish the minimum20 % outage will result in large changes in composition of the remainingliquid due to fractional distillation. It is important that only liquid bevented from the cylinder, and that venting be stopped at the first indicationof va
41、por. Use of proper liquid venting technique will result in only verysmall changes in composition to the remaining liquid which will not affectFIG. 2 Typical Sample Container and Alternate Purging ConnectionsD1265 11 (2017)14product specification results required for compliance with SpecificationD183
42、5.11.2 For sampling containers without an internal ullagetube, the procedure in 11.2.1 may be used.11.2.1 One acceptable alternative procedure to use is weigh-ing the sample container immediately after filling, and creatingthe ullage before analysis. The procedure is to completely fillthe sample con
43、tainer using slight overflow indication to ensurecomplete filling. Without warming the sample, immediatelyweigh the container plus sample on a balance, and record grossweight. Carefully drain off liquid from the bottom of thevertically oriented container in an environmentally-approvedmanner. Then we
44、igh the vented container, and using the tareweight of the container, estimate the ullage of the sample in thecontainer. Repeat the venting and weighing procedures toobtain 22 % 6 2 % ullage of the sample.12. Checking for Leaks12.1 After eliminating the excess liquid sample so that only80 % or less o
45、f the sample remains, immerse in a water bathand check the sample cylinder for leaks. If a leak is detected atany time during the sampling operation, discard the sample.Repair or replace the leaky container before obtaining anothersample. Alternate procedures such as use of soap/water leakdetection
46、fluid, leak detection instruments or recording of totalcylinder weights may also be used to detect leaks.13. Care of Samples and Sample Containers13.1 Place samples in a cool location as soon as possible.Keep them there until all tests have been completed. Discardany samples in containers which deve
47、lop leaks. Protect thevalves on the sample container, either by packing the containerin a crate in an approved manner or by using a protective cap,so that accidental unseating of the valve or tampering with it isavoided.14. Keywords14.1 liquefied petroleum gases; LPG; samplingASTM International take
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49、ponsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Commi
