1、Designation: F1281 17 An American National StandardStandard Specification forCrosslinked Polyethylene/Aluminum/CrosslinkedPolyethylene (PEX-AL-PEX) Pressure Pipe1This standard is issued under the fixed designation F1281; the number immediately following the designation indicates the year oforiginal
2、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 covers a coextruded crosslinked poly-ethylene co
3、mposite pressure pipe with a welded aluminum tubereinforcement between the inner and outer layers. The innerand outer crosslinked polyethylene layers are bonded to thealuminum tube by a melt adhesive. Included is a system ofnomenclature for the crosslinked polyethylene-aluminum-crosslinked polyethyl
4、ene (PEX-AL-PEX) pipes, the require-ments and test methods for materials, the dimensions of thecomponent layers and finished pipe, adhesion tests, and theburst and sustained pressure performance. Also given are therequirements and methods of marking. The pipe covered bythis specification is intended
5、 for use in potable water distribu-tion systems for residential and commercial applications, waterservice, underground irrigation systems, and radient panelheating systems, baseboard, snow- and ice-melt systems, andgases that are compatible with the composite pipe and fittings.1.2 This specification
6、 covers only composite pipes incorpo-rating a welded aluminum tube. Pipes consisting of metalliclayers not welded together are outside the scope of thisspecification.1.3 Specifications for connectors for use with pipe meetingthe requirements of this specification are given in Annex A1.1.4 This speci
7、fication excludes polyethylene-aluminum-polyethylene pipes (see Specification F1282).1.5 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.6 The following precautionary caveat pertains only to thetest methods portion, Section 9
8、, of this specification: Thisstandard does not purport to address all of the safety concerns,if any, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety, health andenvironmental practices and determine the applicability ofregulatory limitatio
9、ns 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 by the World Trade Organization Tech
10、nicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1598 Test Method for Time-to-Failure of Plastic PipeUnder Constant Internal PressureD1599 Test Method for Resistance to Short-Tim
11、e HydraulicPressure of Plastic Pipe, Tubing, and FittingsD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD1898 Practice for Sampling of Plastics (Withdrawn 1998)3D2122 Test Method for Determining Dimensions of Ther-moplastic Pipe and FittingsD2765 Test Methods for Determination of Gel Co
12、ntent andSwell Ratio of Crosslinked Ethylene PlasticsD3350 Specification for Polyethylene Plastics Pipe and Fit-tings MaterialsE8 Test Methods for Tension Testing of Metallic MaterialsF412 Terminology Relating to Plastic Piping SystemsF1282 Specification for Polyethylene/Aluminum/Polyethylene (PE-AL
13、-PE) Composite Pressure PipeF1974 Specification for Metal Insert Fittings forPolyethylene/Aluminum/Polyethylene and CrosslinkedPolyethylene/Aluminum/Crosslinked Polyethylene Com-posite Pressure Pipe2.2 National Sanitation Foundation Standard:Standard No. 61 Drinking Water System ComponentsHealth Eff
14、ects41This specification is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.11 onComposite.Current edition approved Aug. 1, 2017. Published August 2017. Originallyapproved in 1990. Last previous edition approved in 2011 as F1
15、281 11. DOI:10.1520/F1281-17.2For 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.3The last approved version of th
16、is historical standard is referenced onwww.astm.org.4Available from NSF International, P.O. Box 130140, 789 N. Dixboro Rd., AnnArbor, MI 48113-0140, http:/www.nsf.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, We
17、st 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 T
18、rade Organization Technical Barriers to Trade (TBT) Committee.1Standard No. 14 Plastics Piping System Components andRelated Materials42.3 Federal Standard:Fed. Std. No. 123 Marking for Shipments (Civil Agencies)52.4 Military Standard:MIL-STD-129 Marking for Shipment and Storage52.5 Uniform Classific
19、ation Committee Standard:Uniform Freight Classification62.6 National Motor Freight Traffc Association Standard:National Motor Freight Classification73. Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology F412, and abbreviations are in accordance with Termi-nology D1600, unless
20、otherwise specified.3.2 Definitions of Terms Specific to This Standard:3.2.1 assemblythe joint between a fitting and a length ofpipe.3.2.2 PEX-AL-PEX pipecomposite pipe produced by co-extrusion or extrusion of layers of polyethylene/aluminum/polyethylene bonded together with a melt adhesive and cros
21、s-linked by irradiation or chemical means in combination heatand moisture.3.2.3 pipe hoop stressfor simplicity the value of the hoopstress quoted assumes a homogeneous wall. Local values ofstress will vary with the different layers (see 3.2.3.1).3.2.3.1 DiscussionThick walled plastic pipes producedf
22、rom one material have hoop stresses that vary through thewall, and are usually described by the Lame Theory. Thecomposite nature of the PEX-AL-PEX pipe, composed ofmaterials with very different Youngs Modulus values, will, onpressurization, not have a uniform stress distribution throughthe thickness
23、 of the wall of the pipe. The PEX-AL-PEX pipeshave a hoop stress distribution that differs substantially fromboth the thick and thin walled pipe cases.4. Pipe Classification4.1 Pipe DiameterThe PEX-AL-PEX pipes are classifiedby the outside diameter.4.2 Pipe Dimension RatioThe concept of dimension ra
24、tiois not relevant to PEX-AL-PEX composite pipes, and cannotbe used to relate pressure rating with total wall thickness.5. Materials5.1 GeneralThe PEX-AL-PEX pipe is composed of onemetallic layer, two layers of polymeric adhesive, and twolayers of crosslinked polyethylene. For pipe made to thisspeci
25、fication the constituent materials must meet the followingrequirements:5.2 AluminumThe aluminum shall have a thickness asspecified in Table 1. The material shall have minimum elon-gations and ultimate tensile strengths of 20 % and 100 MPa(14 600 psi), respectively. The tests shall be conducted accor
26、d-ing to Test Methods E8.5.3 Crosslinked Polyethylene:5.3.1 The polyethylene shall be, in the final finished state inthe pipe, crosslinked as defined in Terminology D883.5.3.2 Polyethylene plastics used to make pipe meeting therequirements of this specification shall be virgin resin meetingthe requi
27、rements of either Grade PE20A, B, or C; GradePE23A, B, or C; Grade PE30A, B, or C; or Grade PE33A, B,or C in accordance with Specification D3350.5.3.3 Class B compounds shall have sufficient ultraviolet(UV) stabilizers to protect the pipe from deleterious effects dueto continuous outdoor exposure du
28、ring storage and shipping.Pipe produced from Class B compounds are not suitable forexposed outdoor application. Class A, B, and C compoundsshall have sufficient antioxidants to meet the requirements inSpecification D3350.5.4 Melt AdhesiveThe material shall have a density cell of1, 2, or 3; a melt in
29、dex cell of 1, 2, or 3; and a color code ofA or B, in accordance with Specification D3350.5Available from DLA Document Services, Building 4/D, 700 Robbins Ave.,Philadelphia, PA 19111-5094, http:/quicksearch.dla.mil.6Available from the Uniform Classification Committee, Suite 1106, 222 SouthRiverside
30、Plaza, Chicago, IL 60606.7Available from the National Motor Freight Traffic Association, Inc., NationalMotor Freight Classification, American Tracking Associations, Inc., Traffic Dept.,1616 P St., NW, Washington, DC 20036.TABLE 1 Outside Diameters, Aluminum Thickness, and Tolerances for PEX-AL-PEXDi
31、ameterNominal(DN)NominalPipe Size(NPS)Minimum OutsideDiameter, mm (in.)Tolerance on Minimum,mm (in.)Maximum Out-of-Roundness,Amm (in.)Minimum AluminumThickness, mm (in.)Tolerance on Thickness,mm (in.)1238 12.00 (0.472) +0.30 (0.012) 0.3 (0.012) 0.18 (0.007) +0.09 (+0.0035)1614 16.00 (0.630) +0.30 (0
32、.012) 0.4 (0.016) 0.18 (0.007) +0.15 (+0.006)2058 20.00 (0.787) +0.30 (0.012) 0.5 (0.020) 0.23 (0.009) +0.23 (+0.009)2534 25.00 (0.984) +0.30 (0.012) 0.5 (0.020) 0.23 (0.009) +0.09 (+0.0035)2678 26.00 (1.022) +0.30 (0.012) 0.5 (0.020) 0.53 (0.021) +0.10 (+0.004)32 1 32.00 (1.260) +0.30 (0.012) 0.5 (
33、0.020) 0.28 (0.011) +0.09 (+0.0035)40 114 39.95 (1.573) +0.30 (0.012) 0.5 (0.020) 0.33 (0.013) .50 112 49.90 (1.964) +0.30 (0.012) 0.5 (0.020) 0.47 (0.018) .63 2 62.90 (2.484) +0.40 (0.016) 0.5 (0.020) 0.57 (0.022) .75 214 75.10 (2.957) +0.60 (0.024) 1.0 (0.039) 0.67 (0.026) .AThe out-of-roundness s
34、pecification applies only to tubing prior to coiling.F1281 1725.5 Rework MaterialThe use of reclaimed, recycled, orrework plastics is not permitted.6. Requirements6.1 GeneralThe requirements and test methods in thisspecification cover PEX-AL-PEX pipes. Tests on the indi-vidual layers that comprise t
35、his composite pipe are outside thescope of this specification. The raw materials used, however,must conform to the requirements as set out in Section 5.6.2 Dimensions and Tolerances of Pipe:6.2.1 Pipe DiameterThe minimum outside diameter andtolerances of the pipe shall meet the requirements given in
36、Table 1, when measured in accordance with 9.1 and 9.1.2.Maximum and minimum (out-of-roundness) tolerances applyonly to measurements made on pipe prior to coiling.6.2.2 Pipe Wall ThicknessThe total pipe wall thicknessshall meet the requirements given in Table 2, when measuredin accordance with 9.1 an
37、d 9.1.3. The minimum wall thicknessat any point of measurement of the pipe shall not be less thanthe value specified in Table 2.6.2.3 Inner and Outer Crosslinked Polyethylene LayerThicknessesThe thicknesses of the inner and outer layers ofcrosslinked polyethylene in the PEX-AL-PEX pipe shall havemin
38、imum values and tolerance as specified in Table 2, exceptfor the polyethylene material in the outer PEX layer overlayingthe weld, which shall have a minimum thickness of half thosespecified in Table 2. The polyethylene thicknesses shall bemeasured in accordance with 9.2.6.2.4 Pipe LengthThe pipe sha
39、ll be supplied coiled or instraight lengths as agreed upon with the purchaser and with anallowable tolerance of 0 mm (0 in.).6.3 Adhesion Test:6.3.1 For Sizes 0912 (38) to 2532 (1) there shall be nodelamination of the PEX andAL, either on the bore side or theoutside (see Fig. 1). The test shall be c
40、onducted in accordancewith 9.3.1.6.3.2 The adhesion test of the PEX-layer to the aluminumfor Sizes 3240 (114) to 6075 (212) is carried out by a separationtest. The minimum adhesive force is specified in Table 3. Theadhesive force shall not fall below these levels. The test shallbe conducted in accor
41、dance with 9.3.2.6.4 Apparent Tensile Strength of PipeThe pipe rings,when tested in accordance with 9.4, shall meet the minimumstrength specifications defined in Table 4.6.5 Burst PressureThe minimum burst pressure for PEX-AL-PEX pipe shall be as given in Table 4, when determined inaccordance with 9
42、.5.6.6 Sustained PressureThe PEX-AL-PEX pipe shall notfail, balloon, burst, or weep, as defined in Test Method D1598,when tested for 10 h at the test at the test pressure given inTable 5 at a temperature of 82C (180F) in accordance with9.6.6.7 Gel ContentWhen tested in accordance with 9.7, thegel co
43、ntent of the inner and outer tubes of crosslinkedpolyethylene shall have minimum values of either 65 % for thefully crosslinked silane material or 60 % for radiation cross-linked polyethylene. Test Methods D2765 defines gel content(see Note 2).NOTE 1The gel test is one of several methods capable of
44、indicatingthe degree of crosslinking. The different methods for assessing degree ofcrosslinking do not necessarily agree, so conformity to this specificationrequires degree of crosslinking to be determined in accordance with 9.7only.7. Workmanship7.1 The pipe shall be free of visible cracks, holes,
45、foreigninclusions, blisters, and other known injurious defects. Thepipe shall be as uniform as practicable in color, opacity,density, and other physical properties.8. Sampling and Conditioning8.1 SamplingTake a sample of the PEX-AL-PEX pipesufficient to determine conformance with this specification.
46、The number of specimens designated for each test shall betaken from pipe selected at random in accordance with therandom sampling plan of Practice D1898.NOTE 2Sample size and testing frequency of lots for quality controlmust be established by the manufacturer to ensure conformance to thespecificatio
47、n. Sampling and frequency will vary with the specific circum-stances.8.2 Test SpecimensNot less than 50 % of the test speci-mens required for any pressure test shall have at least part ofthe marking in their central sections. The central section is thatportion of the pipe that is at least one pipe d
48、iameter away froman end closure.8.3 ConditioningCondition the specimens at 23 6 2C(73.4 6 3.6F) and 50 6 5 % relative humidity for not lessthan 40 h prior to test in accordance with Procedure A ofTABLE 2 Wall Thickness for PEX-AL-PEX Composite PipeDiameter Nominal(DN)Nominal Pipe Size(NPS)Total Wall
49、Thickness, min,mm (in.)WallTolerance(+) mm (in.)Outer PEXLayer Thickness,min, mm (in.)Inner PEXLayer Thickness,min, mm (in.)1238 1.60 (0.063) 0.40 (0.016) 0.40 (0.016) 0.70 (0.028)1614 1.65 (0.065) 0.65 (0.022) 0.40 (0.016) 0.90 (0.035)2058 1.90 (0.075) 0.40 (0.016) 0.40 (0.016) 0.96 (0.038)2534 2.25 (0.089) 0.50 (0.020) 0.40 (0.016) 1.10 (0.043)2678 3.00 (0.118) 0.33 (0.013) 0.40 (0.016) 1.32 (0.052)32 1 2.90 (0.114) 0.60 (0.024) 0.40 (0.016) 1.34 (0.053)40 114 3.40 (0.134) 0.60 (0.024) 0.40 (0.016) 1.45 (0.057)50 112 4.00 (0.15
