1、Designation: F1924 12 An American National StandardStandard Specification forPlastic Mechanical Fittings for Use on Outside DiameterControlled Polyethylene Gas Distribution Pipe and Tubing1This standard is issued under the fixed designation F1924; the number immediately following the designation ind
2、icates the year oforiginal adoption or, in the case of revision, 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 specification describes requirement
3、s and test meth-ods for the qualification of plastic bodied mechanical fittingsfor use with outside diameter controlled polyethylene (PE) gasdistribution pipe, nominal 2 pipe size (IPS) and smallercomplying with Specification D2513. In addition, it specifiesgeneral requirements of the material from
4、which these fittingsare made.1.2 The test methods described in this specification are notintended to be used as routine quality control tests.1.3 This specification covers the types of mechanical fittingsdescribed in 3.2.1.4 The values stated in inch-pound units are to be regardedas standard. The va
5、lues given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 The following safety hazards caveat pertains only to thetest method portion, Section 7, of this specification. Thisstandard does not purport to address all of t
6、he safety concerns,if any, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.1.6 The text of this specification references notes andfootnotes, which
7、 provide explanatory material.These notes andfootnotes (excluding those in tables and figures) shall not beconsidered as requirements of this specification.2. Referenced Documents2.1 ASTM Standards:2D638 Test Method for Tensile Properties of PlasticsD1598 Test Method for Time-to-Failure of Plastic P
8、ipeUnder Constant Internal PressureD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD2513 Specification for Polyethylene (PE) Gas PressurePipe, Tubing, and FittingsD2837 Test Method for Obtaining Hydrostatic Design Basisfor Thermoplastic Pipe Materials or Pressure Design Basisfor Thermopl
9、astic Pipe ProductsF412 Terminology Relating to Plastic Piping SystemsF1588 Test Method for Constant Tensile Load Joint Test(CTLJT)F2897 Specification for Tracking and Traceability EncodingSystem of Natural Gas Distribution Components (Pipe,Tubing, Fittings, Valves, and Appurtenances)2.2 ASME Standa
10、rd:ASME B31.8 Gas Transmission and Distribution PipingSystems32.3 Federal Standard:CFR, Title 49, Part 192 Pipeline Safety Regulations42.4 Plastics Pipe Institute Standard:PPI TR-4 Recommended Hydrostatic Strengths and DesignStresses for Thermoplastic Pipe and Fittings Compounds53. Terminology3.1 De
11、finitionsDefinitions of terms used in this specifica-tion are in accordance withTerminology F412 unless otherwisespecified. Abbreviations are in accordance with TerminologyD1600 unless otherwise specified.3.1.1 The Gas Industry terminology used in this specifica-tion is in accordance with ASME B31.8
12、 or CFR, Title 49, Part192 unless otherwise indicated.3.1.2 The term “pipe” used herein refers to both “pipe” and“tubing” unless specifically stated otherwise.The term “fitting”refers to a mechanical connecting device as described in 3.1.4and 3.1.6.1This specification is under the jurisdiction of AS
13、TM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.60 on Gas.Current edition approved April 1, 2012. Published May 2012. Originallyapproved in 1998. Last previous edition approved in 2011 as F192405(2011). DOI:10.1520/F1924-12.2For referenced ASTM standard
14、s, 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 American Society of Mechanical Engineers (ASME), ASMEInternational Headqua
15、rters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.5Available from Plastics Pipe Institute (PPI), 105 Decker Court, Suite 825,Irv
16、ing, TX 75062, http:/www.plasticpipe.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 reco
17、gnized 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 (TBT) Committee.13.1.3 joint, nthe location at which two pieces of pipe, or apip
18、e and a fitting are connected together, for example, aninstalled coupling has two joints.3.1.4 joint, mechanical, na connection between pipingcomponents employing physical force to develop a seal orproduce alignment.3.1.5 long-term strength (LTS), nthe estimated tensilestress that when applied conti
19、nuously will cause failure at100 000 h. This is the intercept of the stress regression linewith the 100 000 h coordinate.3.1.6 mechanical fitting, nfitting for making a mechanicaljoint to provide for pressure integrity, leak tightness, anddepending on category, as defined in this specification, resi
20、s-tance to end loads.3.1.6.1 category 1 mechanical fitting, nfitting for assem-bling pipes, which includes a compression zone(s) to providefor pressure integrity, leak tightness, and resistance to endloads sufficient to cause no less than 25 % elongation of the PEpiping as described in this specific
21、ation.3.1.6.2 category 2 mechanical fitting, nfitting for assem-bling pipes, which includes a compression zone(s) to providefor pressure integrity and leak tightness only. Category 2fittings do not provide for resistance to end loads.3.1.7 MAOP, nthe Maximum Allowable Operating Pres-sure of the fuel
22、 gas piping system, in psig, as determined inaccordance with CFR, Title 49, Part 192.121 and as repre-sented in the following:MAOP 5 P 5 2 3 S/R 2 1! 3 fD(1)where:S = the PE materials HDB as published in PPI TR-4.R = the pipes dimension ratio determined by dividing thepipes specified nominal outside
23、 diameter by the pipesspecified nominal wall thickness; and,fD= the design (derating) factor for thermoplastic fuel gaspiping as set by the authority having jurisdiction. Inthe United States the design factor is cited in CFR,Title 49 Part 192.121.3.2 Types of Mechanical Fittings:3.2.1 in-line fittin
24、g, nmechanical fitting used to make amechanical joint where the bore axis of the compression andsealing zones of the fitting is essentially the same as theconnected piping, for example, couplings, ells, and tees.3.2.2 mechanical saddle fitting, nmechanical fitting usedto make a mechanical joint that
25、 allows a lateral connection toan existing main in which a portion of the fitting is contouredto match the O.D. of the pipe to which it is attached. Hereinreferred to as the saddle fitting mating pipe.4. Materials and Manufacture Requirements4.1 Plastic pressure containing materials subject to conti
26、nu-ous stress, either hoop or axial, shall have an ASTM materialspecification, and the materials long-term strength, such as thelong-term hydrostatic strength, determined in accordance withTest Method D2837, excepting that failure data can be obtainedfrom specimens such as the following: tensile bar
27、s, planestrain, or actual fitting samples. A material listing in PPI TR-4document is evidence of compliance with this paragraph forthird party certifying and listing agencies.4.2 The physical properties of each material used to producethe fitting shall be available from the fitting manufacturer upon
28、request.4.3 Specifications outlining all the physical properties andeffects of environmental conditions for materials of manufac-ture shall be available from the fitting manufacturer uponrequest.NOTE 1Materials in long-term contact with natural gas of line qualityand LP gas vapor should be demonstra
29、ted not to adversely affect theperformance of the fitting.NOTE 2Materials should have a demonstrated resistance to environ-mental stress cracking when exposed, under stress, to chemical com-pounds encountered in, or external to gas piping systems, and a demon-strated resistance to bacteriological de
30、composition. Such compoundsinclude, but are not limited to, ice thawing chemicals, fertilizers,insecticides, herbicides, leak detection fluids, acids, bases and antifreezesolutions used to thaw frozen lines. The effects of liquid environments,such as antifreeze agents, odorants, and hydrocarbons are
31、 known to bedeleterious to some plastics, particularly when under service conditions.5. Dimensions5.1 The dimensions and tolerances shall be determined bythe manufacturer.6. Qualification Requirements6.1 GeneralUnless otherwise specified, each nominal sizeof fitting shall be tested. Testing of the t
32、hickest wall pipe thatthe fitting is designed to be used with qualifies the use of thatfitting with pipe of lesser wall thickness.6.1.1 Mechanical joint qualifications shall be performed onassembled joints using the fitting manufacturers joining pro-cedure. All mechanical fittings offered by the man
33、ufacturershall be capable of meeting the requirements of this standardwhen connecting polyethylene gas piping complying withSpecification D2513. To verify the structural integrity of thefitting body, representative samples shall be subjected to therequirements of 6.2.1. It is not the intent of this
34、specification torequire testing of all fitting configurations, that is, tees, ells,etc., but each mechanical joint design in each size.6.1.2 All mechanical fittings described in 3.2 shall have aninternal pipe reinforcing tubular insert stiffener that extends atleast under the seal and gripping devic
35、e, where used. Thesaddle portion of saddle-type fittings do not require an internaltubular stiffener due to the nature of the connection.6.2 Performance Requirements:6.2.1 Elevated Temperature Sustained PressureThefitting, joint or pipe in the area affected by the fitting shall notfail as defined in
36、 Test Method D1598, when tested in accor-dance with 7.2.The fitting or joint meets this requirement whentested in accordance with any one of the three conditions (A, B,or C) listed in 7.2.6.2.2 Tensile StrengthThe pipe joint shall accommodatethe tensile loadings when tested in accordance with 7.3.6.
37、2.2.1 In-Line Fittings, Category 1The joint shall pro-vide resistance to a force on the pipe joint equal to or greaterF1924 122than that which will cause no less than 25 % elongation of pipe,or the pipe fails outside the joint area when tested in accor-dance with 7.3.6.2.2.2 In-Line Fittings, Catego
38、ry 2A joint design thatprovides a seal only. A mechanical joint designed for thiscategory excludes any provisions in the design of the joint toresist any axial pullout forces; therefore, tensile tests are notrequired.6.2.2.3 Mechanical Saddle FittingsThe joint between thesaddle and mating pipe shall
39、 not fail by rotation or leakagewhen tested in accordance with 7.6.6.2.2.4 Joint restraint capabilities less than as defined aboveshall constitute failure of the test.6.2.3 Temperature Cycling TestThe mechanical joint shallprovide a pressure seal after 10 cycles of the temperaturecycling test when t
40、ested in accordance with 7.4.6.2.4 Constant Tensile Load Joint Test The joint shall notfail by leakage or pullout when loaded to an axial tensile stressof 1320 psi (9.1 MPa) and tested in accordance with 7.5.7. Test Methods7.1 GeneralThe test methods in this specification covermechanical joint desig
41、ns.Test methods that are applicable fromother specifications will be referenced in the section pertainingto that particular test.7.1.1 ConditioningUnless otherwise specified, conditionthe specimens (pipe and fittings) prior to joining at 73.4 6 3.6F (23 6 2 C) for not less than 16 h.7.1.2 Test Condi
42、tionsConduct the tests at the standardlaboratory temperature of 73.4 6 3.6 F (23 6 2 C) unlessotherwise specified.7.1.3 Test SpecimensTest joints shall be prepared with theappropriate size PE pipe, complying with the dimensionalrequirements of Specification D2513, in accordance with themanufacturers
43、 joining procedures.7.2 Elevated Temperature Sustained Pressure Test:7.2.1 The apparatus and report shall be as specified in TestMethod D1598. Test six joints assembled in accordance with6.1.1.7.2.2 The assembled joints shall be tested in accordancewith Test Method D1598 with the exception that it i
44、s notrequired that 12 in. or five times the nominal outside diameterof the pipe used in conducting the test be placed on each sideof the fitting being tested. The test shall be conducted at one ofthe time/temperature/hoop stress combinations shown in Table1 with the test pressure calculated using Eq
45、 2. If ductile failureoccurs in the pipe at 176F (80C)/670 psi (4.6 MPa) hoopstress, retest at 176F (80C)/580 psi (4.0 MPa) hoop stress.P 52SDR 2 1(2)where:P = test pressure, psig,S = hoop stress from Table 1, andDR = dimension ratio (OD/wall).7.2.3 Failure of two of the six specimens tested shallco
46、nstitute failure in the test. Failure of one of the six specimenstested is cause for retest of six additional specimens. Failure ofone of the six specimens in retest shall constitute failure of thetest. Evidence of failure of the pipe shall be as defined in TestMethod D1598.7.3 Tensile Strength Test
47、:7.3.1 Test specimens shall be prepared so that the minimumlength of unreinforced pipe is equal to five times the nominaloutside diameter of the pipe being tested. It is permissible totest multiple joints together provided the minimum length ofunreinforced pipe (as stated above) exists on at least o
48、ne joint.7.3.2 In-line fittings shall be tested with the apparatus andreported as specified in Test Method D638. Test six joints.7.3.3 The test shall be conducted at 73.4 6 3.6F (23 62C).7.3.4 The speed of the testing shall be 0.2 in. (5 mm)/min625 %.7.3.5 Failure of any sample shall constitute fail
49、ure of thetest.7.4 Temperature Cycling Test:7.4.1 Tests shall be conducted on six of the smallest and sixof the largest nominal pipe sizes of each mechanical jointdesign and assembled in accordance with 6.1.1.7.4.2 Leak test specimens at ambient at 7 6 3 psig and aminimum of 1.5 MAOP.7.4.3 Cool specimens to a temperature of 20 6 3.6F (296 2C) and maintain for a minimum of 2.5 h.7.4.4 Condition specimens to a temperature of 140 6 3.6F(60 6 2C) and maintain for a minimum of 2.5 h.7.4.5 Repeat 7.4.3 and 7.4.4 for a total of 10 cycles.7.
