1、Designation:D370021Standard Practice forObtaining LPG Samples Using a Floating Piston Cylinder1This standard is issued under the fixed designation D3700;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A numb
2、er 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 practice covers the equipment and procedures forobtaining a representative sample of liquefied petroleum gas(LPG),such as specified in AS
3、TM Specification D1835,GPA2140,and comparable international standards.It may also beused for other natural gas liquid(NGL)products that arenormally single phase(for example,NGL mix,field butane,and so forth),defined in other industry specifications orcontractual agreements,and for volatile(higher va
4、por pres-sure)crude oils.NOTE1Some floating piston cylinders have such tight piston sealsthat the vapor pressure of some high vapor pressure crude oils may not besufficient to allow sampling without a handle to move the piston.Analternative sampling practice for UN Class 3 liquids(under 300 kPa at52
5、 C)is Practice D8009,which utilizes a Manual Piston Cylinder(MPC)sampler.1.2 This practice is not intended for non-specification prod-ucts that contain significant quantities of undissolved gases(N2,CO2),free water or other separated phases,such as raw orunprocessed gas/liquids mixtures and related
6、materials.Thesame equipment can be used for these purposes,but additionalprecautions are generally needed to obtain representativesamples of multi-phase products(see Appendix X1).1.3 This practice includes recommendations for the locationof a sample point in a line or vessel.It is the responsibility
7、 ofthe user to ensure that the sampling point is located so as toobtain a representative sample.1.4 The values stated in SI units are to be regarded asstandard.1.4.1 ExceptionThe values given in parentheses are forinformation only.1.5 This standard does not purport to address all of thesafety concer
8、ns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices,and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with interna
9、tionally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1265 Pract
10、ice for Sampling Liquefied Petroleum(LP)Gases,Manual MethodD1835 Specification for Liquefied Petroleum(LP)GasesD4175 Terminology Relating to Petroleum Products,LiquidFuels,and LubricantsD8009 Practice for Manual Piston Cylinder Sampling forVolatile Crude Oils,Condensates,and Liquid PetroleumProducts
11、2.2 GPA Midstream Association Standards:3GPA 2140 Liquefied Petroleum Gas Specifications and TestMethodsGPA 2174 Obtaining Liquid Hydrocarbon Samples forAnalysis by Gas Chromatography3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this practice,refer toTerminology D4175.3.1.2 flo
12、ating piston cylinder(FPC),na high pressuresample container,with a free floating internal piston thateffectively divides the container into two separate compart-ments.3.1.2.1 DiscussionA floating piston cylinder is used tocollect a sample of liquid under pressure without the formationof a gaseous ph
13、ase which can result in changes in thecomposition of the liquid sample.3.1.3 maximum fill volume(reduced fill volume),nthevolume of a container that may be safely occupied by the liquidsample,usually expressed as a percentage of the total capacity.1This practice is under the jurisdiction of ASTM Com
14、mittee D02 on PetroleumProducts,Liquid Fuels,and Lubricants and is the direct responsibility of Subcom-mittee D02.H0 on Liquefied Petroleum Gas.Current edition approved Dec.1,2021.Published December 2021.Originallyapproved in 1978.Last previous edition approved in 2016 as D3700 16.DOI:10.1520/D3700-
15、21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from GPA Midstream Association,6526 E.60th St.,Tulsa
16、,OK74145,www.gpaglobal.org*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(T