1、Designation: F 2138 01e1An American National StandardStandard Specification forExcess Flow Valves for Natural Gas Service1This standard is issued under the fixed designation F 2138; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.e1NOTESection 15 was added editorially revised in December 2002.1. Scope1.1 This specification covers requirements and
3、 test methodsfor excess flow valves for use in thermoplastic natural gaspiping systems. However, it is expected that excess flow valvesmanufactured to the requirements of this specification may alsobe used in other natural gas piping systems.1.2 Excess flow valves covered by this specification arede
4、signed for insertion into components for natural gas systemssuch as pipe, tubing, or fittings in sizes from 1/2 CTS to 2 IPS.1.3 The tests required by this specification are intended todetermine the performance characteristics of an excess flowvalve installed in a straight piece of pipe. An excess f
5、low valvecould possibly be installed in a straight piece of pipe, in aservice tee outlet, as part of a mechanical coupling, or in otherconfigurations. The performance characteristics of the excessflow valve may be significantly different for each installedconfiguration. Users should conduct their ow
6、n tests to deter-mine the installed performance characteristics or contact theEFV manufacturer for test data for the installed configuration.Additional guidance on selection and installation of excessflow valves is included in Appendix X1.1.4 The tests required by this specification are not intended
7、to be routine quality control tests.1.5 The values given in parentheses are for informationalpurposes 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 a
8、nd health practices and determine the applica-bility of regulatory requirements prior to use.2. Referenced Documents2.1 ASTM Standards:D 1600 Terminology for Abbreviated Terms Relating toPlastics2F 412 Terminology Relating to Plastic Piping Systems3F 1802 Test Method For Performance Testing of Exces
9、sFlow Valves33. Terminology3.1 Definitions of Terms:3.1.1 Definitions are in accordance with Terminology F 412,unless otherwise specified. Abbreviations are in accordancewith Terminology D 1600.3.1.2 bypass flow, nan intentional rate of passage ofnatural gas through an EFVB after trip, which will al
10、lowupstream and downstream pressure to equalize across thedevice to automatically reset to the open position after removalof a fault condition.3.1.3 excess flow valve, EFV, na device installed in anatural gas piping system to automatically stop or limit thepassage of natural gas when the rate of pas
11、sage of natural gasthrough the device exceeds a predetermined level.3.1.4 excess flow valve bypass, EFVB, nan EFV designedto limit the flow of gas after trip to a small predetermined leveland to reset automatically after the pressure is equalized acrossthe valve.3.1.5 excess flow valve non-bypass, E
12、FVNB, nan EFVdesigned to stop the flow of gas after trip and to be resetmanually.3.1.6 leak rate, nthe flow of natural gas through anEFVNB after trip.3.1.7 maximum inlet pressure, nthe maximum pressure,as stated by the EFV manufacturer, at which an EFV isdesigned to function.3.1.8 minimum inlet pres
13、sure, nthe minimum pressure, asstated by the EFV manufacturer, at which an EFV is designedto function.3.1.9 pipe, nrefers to both pipe and tubing.3.1.10 reset, vchanging an EFV from a closed position toan open position.3.1.11 temperature rating, nthe temperature range, asstated by the EFV manufactur
14、er, within which an EFV isdesigned to function.1This specification is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.60 on Gas.Current edition approved Sept. 10, 2001. Published October 2001.2Annual Book of ASTM Standards, V
15、ol 08.01.3Annual Book of ASTM Standards, Vol 08.04.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.12 trip, nclosure of an EFV.3.1.13 trip flow, nthe rate of passage of natural gasthrough an EFV that will cause the EFV to stop or
16、 limit thepassage of natural gas.4. Ordering Information4.1 Purchasers should consider specifying the followingcharacteristics when ordering an EFV:4.1.1 EFVB or EFVNB,4.1.2 Trip flow (see 9.1.1),4.1.3 Maximum inlet pressure (see Section 7),4.1.4 Temperature rating range (see Section 8),4.1.5 Minimu
17、m inlet pressure, and4.1.6 Special considerations for insertion of EFV.5. Materials and Manufacture5.1 The physical properties of each material used to producean EFV shall be available from the EFV manufacturer uponrequest.NOTE 1Materials in long-term contact with natural gas of line qualityshould b
18、e demonstrated to not adversely affect the performance of theEFV.NOTE 2Materials should have a demonstrated resistance to environ-mental stress cracking when exposed, under stress, to chemical com-pounds encountered in natural gas piping systems. Such compoundsinclude, but are not limited to, antifr
19、eeze solutions used to thaw frozenlines. The effects of liquid environments such as antifreeze agents,odorants, and hydrocarbons are known to be deleterious to some plastics,particularly when under service conditions.6. Dimensions6.1 The EFV shall be of appropriate dimensions for the pipeor fitting
20、in which it is intended to be inserted.7. Maximum Inlet Pressure7.1 EFVs manufactured under this specification shall have amaximum inlet pressure of at least 125 psig.8. Temperature Rating Range8.1 EFVs manufactured under this specification shall have atemperature rating range of -20 to 140F (-29 to
21、 60C).9. Design Qualification Requirements9.1 Performance Requirements:9.1.1 Trip FlowThe trip flow shall not be less than theminimum trip flow stated by the EFV manufacturer and shallnot exceed 1.5 times the minimum trip flow stated by the EFVmanufacturer at any given pressure between the minimum a
22、ndmaximum inlet pressures, when tested in accordance with 12.2.9.1.2 Leak RateThe leak rate of an EFVNB shall notexceed 0.40 standard ft3/h (0.011 m3/h) when operating be-tween the minimum and maximum inlet pressures, when testedin accordance with 12.3.9.1.3 Bypass FlowThe bypass flow of an EFVB sha
23、ll notexceed 20 standard ft3/h (0.566 m3/h) at a 10 psig (0.07 MPa)inlet pressure, when tested in accordance with 12.4. At all otherpressures between the minimum and maximum inlet pressures,the bypass flow of an EFVB shall not exceed the EFVmanufacturers stated value when tested in accordance with12
24、.4.9.1.4 Pressure DropThe pressure drop across the EFVshall not exceed the maximum pressure drop stated by the EFVmanufacturer at each flow rate listed in Test Method F 1802,section 4.2.3, Pressure Drop at Flow Rates Less than Closure,and at all inlet pressures between the minimum and maximuminlet p
25、ressures, when tested in accordance with 12.5.9.1.5 ResetThe EFV shall reset within the parametersstated by the EFV manufacturer at all inlet pressures betweenthe minimum and maximum inlet pressures, when tested inaccordance with 12.6.9.1.6 Snap Acting LoadsThe EFV shall not close whentested in acco
26、rdance with 12.7.9.1.7 Cycle TestingAfter the cycle testing described in12.8, the EFV shall meet the requirements of 9.1.1 and 9.1.2 or9.1.3.10. Samples10.1 The minimum sample size for testing against theperformance requirements of 9.1.1-9.1.5 shall be 25. Theminimum sample size for testing against
27、the performancerequirements of 9.1.6 and 9.1.7 shall be 6.11. Specimen Preparation11.1 The tests required by this specification shall be per-formed on an EFV inserted in a straight section of pipe. TheEFV shall be centered between the pipe ends. There shall be atleast five diameters of straight pipe
28、 on each side of the EFV, butthe total length of the straight section of pipe shall not exceed18 in. (45.7 cm).12. Test Methods12.1 General:12.1.1 EFV testing shall be done in accordance with TestMethod F 1802, unless otherwise specified.12.1.2 EFV testing at temperatures other than those listed inT
29、est Method F 1802 may be necessary to establish the EFVtemperature rating.12.2 Trip flow shall be determined as described in TestMethod F 1802, section 10.3, on Trip Flow.12.3 Leak rate for an EFVNB shall be determined asdescribed in Test Method F 1802, section 10.4, Bypass Test orLeak Rate Test.12.
30、4 Bypass flow for an EFVB shall be determined asdescribed in F 1802, section 10.4, Bypass Test or Leak RateTest.12.5 Pressure Drop:12.5.1 The pressure drop testing shall be done as describedin Test Method F 1802, section 4.2.3, Pressure Drop at FlowRates Less than Closure.12.5.2 The pressure drop sh
31、all be calculated based on testresults obtained from the tests described in Test MethodF 1802. In Test Method F 1802, section 10.6.1, System Pres-sure Drop, the EFV is replaced by an equivalent length of 1 in.(25.4 mm) IPS pipe. However, when using Test Method F 1802to determine the pressure drop ac
32、ross an EFV, the EFV shall bereplaced with the same size and length of pipe without the EFV.To calculate the pressure drop, subtract the system pressuredrop in Test Method F 1802, section 10.6.2, System PressureF213801e12Drop, from the total pressure drop in Test Method F 1802,section 10.5.7, Total
33、Pressure Drop.12.6 Reset of an EFVB shall be tested as described in TestMethod F 1802, section 10.7, Reset.12.7 Snap Acting Load TestA test apparatus shall beassembled consisting of the following components in order:inlet supply pressure connection to EFV, no more than 60 ft(18.3 m) of 1 in. (2.54 c
34、m) NPS pipe, full port14 turn ballvalve, no more than 2 ft (.61 m) of 1 in. (2.54 cm) NPS pipe,a flow control valve, no more than 4 ft (1.2 m) of 1 in. (2.54cm) NPS pipe, and a flowmeter venting to atmosphere. Inletpressure shall be 10 psig (0.07 MPa). With the ball valve open,set the flow control v
35、alve so that the flowmeter indicates 75 %of the published EFV minimum trip flow. Completely close theball valve; then reopen the ball valve completely taking nomore than 0.5 s to open.12.8 Cycle TestingThis test shall be performed after allother tests in Section 12 have been completed. The EFV shall
36、be tripped and reset a minimum of 1000 times at the inletpressure of 125 psi. The EFV shall then be tested in accordancewith 12.2 and 12.3 or 12.4.13. Product Marking13.1 If the EFV manufacturer intends to sell the EFV toothers, the outer surface of the EFV shall be marked with thefollowing:13.1.1 A
37、STM F 2138,13.1.2 Manufacturers name or trademark, and13.1.3 Coding that will enable the manufacturer to deter-mine the EFV model as well as the date and location ofmanufacture.13.2 If the EFV manufacturer inserts the EFV into pipe or apiping component prior to shipment to a customer, the mark-ings
38、shown below shall be placed on the outer surface of thepipe or piping component:13.2.1 ASTM F 2138,13.2.2 Manufacturers name or trademark,13.2.3 Type of EFV: Bypass (EFVB) or Non By-Pass(EFVNB),13.2.4 Flow direction arrow,13.2.5 Nominal pipe size, and13.2.6 Coding that will enable the manufacturer t
39、o deter-mine the EFV model as well as the date and location ofmanufacture.13.3 If the EFV manufacturer supplies the EFV componentto another manufacturer for assembly into other products, theEFV manufacturer shall supply the information required by13.2 in an agreed upon format such that it can be pla
40、ced on theouter surface of the final pipe or piping component by the othermanufacturer.14. Production Testing14.1 The manufacturer shall test each EFV prior to ship-ment.14.2 The following tests shall be performed on each EFV:14.2.1 Trip flow,14.2.2 Leak rate for EFVNBs,14.2.3 Bypass flow for EFVBs,
41、 and14.2.4 Reset testing.14.3 EFVs that do not meet the manufacturers publishedperformance requirements for the above tests shall be rejected.15. Quality Assurance15.1 When the product is marked with this designation,F 2138, the manufacturer affirms that the product was manu-factured, inspected, sam
42、pled, and tested in accordance with thisspecification and has been found to meet the requirements ofthis specification.16. Keywords16.1 excess flow valve;(EVF)APPENDIX(Nonmandatory Information)X1. GUIDANCE ON EFV SELECTION AND INSTALLATIONX1.1 GeneralThis appendix is intended to assist ownersof natu
43、ral gas systems in the selection of the appropriate EFVfor inclusion in a pipeline system and to determine the effectsof the EFV installation on the performance of the pipelinesystem.X1.2 EFV SelectionAn EFV should be selected with atrip flow, at the distribution system minimum pressure, abovethe ma
44、ximum customer load, and above the meter capacity.X1.3 Determining Service Line ConfigurationA basicunderstanding of the method for designing service lines isessential to understanding the effects of EFVs on service linedesign. These effects are discussed in X1.4.X1.3.1 Service Line ConfigurationThi
45、s term includes allfactors that affect the flow and cause pressure drop along thelength of a service line. These factors include:X1.3.1.1 Main tap and outlet piping,X1.3.1.2 Service line pipe diameter, wall thickness, androughness, andX1.3.1.3 Fittings, couplings, and valves.X1.3.2 Service Line Flow
46、 and Maximum LengthMaximum service line length is typically determined bygraphing flow versus service line length for a given service lineconfiguration. A longer service line will have decreased flowdue to the increased friction along the inside diameter of thepipeline. This increased friction also
47、results in an increasedF213801e13pressure drop. When the pressure drop along the length of theservice reaches the maximum acceptable value determined bythe operator, the graph ends and the maximum service linelength for the service line configuration is established. Themaximum service line length fo
48、r 1/2 CTS pipe with the sametap, fittings, couplings, and valves for one company may bedifferent from another company due to different maximumacceptable pressure drops. A typical graph is shown in Fig.X1.1.X1.3.3 Service Line Configuration SelectionOwners ofgas distribution systems will typically ha
49、ve a graph, like theone shown in Fig. X1.1, for each service line configuration. Acustomer will have a known maximum load and requiredservice line length. The service line configuration is selected byidentifying the least cost configuration that will meet themaximum customer load at the required service line length.X1.4 EFV Installation Effects on Service LinesThe inclu-sion of an EFV in a service line may cause a change in thegraph of flow versus length. The EFV may add pressure dropand restrict flow through the service line. Fig. X1.2 shows atypica
