1、Designation: F1281 11An 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 a
2、doption 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 com
3、posite 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 polyethyle
4、ne (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 specif
7、ication 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 and healthpractices and determine the applicability of regulatory limita-tions prior to us
9、e.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-Time HydraulicPressure of Plastic Pipe,
10、Tubing, and FittingsD1600 Terminology for Abbreviated Terms Relating toPlasticsD1898 Practice for Sampling of Plastics3D2122 Test Method for Determining Dimensions of Ther-moplastic Pipe and FittingsD2765 Test Methods for Determination of Gel Content andSwell Ratio of Crosslinked Ethylene PlasticsD3
11、350 Specification for Polyethylene Plastics Pipe andFittings MaterialsE8 Test Methods for Tension Testing of Metallic MaterialsF412 Terminology Relating to Plastic Piping SystemsF1282 Specification for Polyethylene/Aluminum/Polyethylene (PE-AL-PE) Composite Pressure PipeF1974 Specification for Metal
12、 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 Effects4Standard No. 14 Plastics Piping System Components an
13、dRelated Materials42.3 Federal Standard:Fed. Std. No. 123 Marking for Shipments (Civil Agencies)51This 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 Sept. 15, 2011. P
14、ublished September 2011. Originallyapproved in 1990. Last previous edition approved in 2007 as F1281 07. DOI:10.1520/F1281-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、 refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from NSF International, P.O. Box 130140, 789 N. Dixboro Rd., AnnArbor, MI 48113-0140, http:/www.nsf.org.5Available from Standardi
16、zation Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5098, Attn: NPODS.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.2.4 Military
17、Standard:MIL-STD-129 Marking for Shipment and Storage52.5 Uniform Classification 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
18、 F412, and abbreviations are in accordance with Termi-nology D1600, unless 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 polye
19、thylene/aluminum/polyethylene bonded together with a melt adhesive and cross-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
20、layers (see 3.2.3.1).3.2.3.1 DiscussionThick walled plastic pipes producedfrom 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, on
21、pressurization, not have a uniform stress distribution throughthe thickness 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 classified
22、by the outside diameter.4.2 Pipe Dimension RatioThe concept of dimension ratiois 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 adhe
23、sive, and twolayers of crosslinked polyethylene. For pipe made to thisspecification 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
24、% and 100 MPa(14 600 psi), respectively. The tests shall be conducted accord-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 t
25、herequirements of this specification shall be virgin resin meetingthe requirements 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 pro
26、tect the pipe from deleterious effects dueto continuous outdoor exposure during 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
27、Melt AdhesiveThe material shall have a density cell of1, 2, or 3; a melt index cell of 1, 2, or 3; and a color code ofA or B, in accordance with Specification D3350.5.5 Rework MaterialThe use of reclaimed, recycled, orrework plastics is not permitted.6. Requirements6.1 GeneralThe requirements and te
28、st methods in thisspecification cover PEX-AL-PEX pipes. Tests on the indi-vidual layers that comprise this 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 P
29、ipe DiameterThe minimum outside diameter andtolerances of the pipe shall meet the requirements given inTable 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.6Available from the Uniform Classif
30、ication Committee, Suite 1106, 222 SouthRiverside 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, A
31、luminum Thickness, and Tolerances for PEX-AL-PEXNominal Pipe Size,mm (in.)Minimum OutsideDiameter, mm (in.)Tolerance on Minimum,mm (in.)Maximum Out-of-Roundness,Amm (in.)Minimum AluminumThickness, mm (in.)Tolerance on Thickness,mm (in.)0912 (38) 12.00 (0.472) +0.30 (0.012) 0.3 (0.012) 0.18 (0.007) +
32、0.09 (+0.0035)1216 (12) 16.00 (0.630) +0.30 (0.012) 0.4 (0.016) 0.18 (0.007) +0.15 (+0.006)1620 (58) 20.00 (0.787) +0.30 (0.012) 0.5 (0.020) 0.23 (0.009) +0.23 (+0.009)2025 (34) 25.00 (0.984) +0.30 (0.012) 0.5 (0.020) 0.23 (0.009) +0.09 (+0.0035)2026 (78) 26.00 (1.022) +0.30 (0.012) 0.5 (0.020) 0.53
33、 (0.021) +0.10 (+0.004)2532 (1) 32.00 (1.260) +0.30 (0.012) 0.5 (0.020) 0.28 (0.011) +0.09 (+0.0035)3240 (114) 39.95 (1.573) +0.30 (0.012) 0.5 (0.020) 0.33 (0.013) .4150 (112) 49.90 (1.964) +0.30 (0.012) 0.5 (0.020) 0.47 (0.018) .5163 (2) 62.90 (2.484) +0.40 (0.016) 0.5 (0.020) 0.57 (0.022) .6075 (2
34、12) 75.10 (2.957) +0.60 (0.024) 1.0 (0.039) 0.67 (0.026) .AThe out-of-roundness specification applies only to tubing prior to coiling.F1281 1126.2.2 Pipe Wall ThicknessThe total pipe wall thicknessshall meet the requirements given in Table 2, when measuredin accordance with 9.1 and 9.1.3. The minimu
35、m wall thicknessat any point of measurement of the pipe shall not be less thanthe value specified in Table 2.6.2.3 Outer Crosslinked Polyethylene Layer ThicknessThe thickness of the outer layer of crosslinked polyethylene inthe PEX-AL-PEX pipe shall have a minimum value andtolerance as specified in
36、Table 2, except for the polyethylenematerial overlaying the weld, which shall have a minimumthickness of half that specified in Table 2. The polyethylenethickness shall be measured in accordance with 9.2.6.2.4 Pipe LengthThe pipe shall be supplied coiled or instraight lengths as agreed upon with the
37、 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 conducted in accordancewith 9.3.1.6.3.2 The adhesion test of the PEX
38、-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 accordance with 9.3.2.6.4 Apparent Tensile Strength of Pipe The pipe rin
39、gs,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 9.5.6.6 Sustained PressureThe PEX-AL-PEX pipe shall notfail, balloo
40、n, 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 content of the inner and outer tubes of crosslinkedpolyethylene shal
41、l 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 indicatingthe degree of crosslinking. The different methods for as
42、sessing 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, foreigninclusions, blisters, and other known injurious defects. Th
43、epipe 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.The number of specimens designated for each test shall betaken fro
44、m 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 thespecification. Sampling and frequency will vary with the specific circum-stanc
45、es.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 diameter away froman end closure.8.3 ConditioningCondition the spec
46、imens 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 ofPractice D618, for those tests where conditioning is required.In cases of disagreement, the tolerances shall be 61C(61.8F) and 62 % relative humidity.8.4 Test ConditionsC
47、onduct the test in the standard labo-ratory atmosphere of 23 6 2C (73.4 6 3.6F) and 50 6 5%relative humidity, unless otherwise specified in the test meth-ods or in this specification. In cases of disagreement, thetolerances shall be 61C (1.8F) and 62 % relative humidity.9. Test Methods9.1 Dimensions
48、 and Tolerances:9.1.1 PipeAny length of the PEX-AL-PEX compositepipe may be used to determine dimensions.9.1.2 Outside DiameterMeasure the outside diameter ofthe PEX-AL-PEX pipe in accordance with Test MethodD2122.9.1.3 Wall ThicknessMake micrometre measurements ofthe wall thickness in accordance wi
49、th Test Method D2122 toTABLE 2 Wall Thickness for PEX-AL-PEX Composite PipeNominal Pipe Size,mm (in.)Total WallThickness, min,mm (in.)WallTolerance(+) mmOuter PEXLayer Thickness,min, mm (in.)Inner PEXLayer Thickness,min, mm (in.)0912 (38) 1.60 (0.063) 0.40 (0.016) 0.40 (0.016) 0.70 (0.028)1216 (12) 1.65 (0.065) 0.65 (0.022) 0.40 (0.016) 0.90 (0.035)1620 (58) 1.90 (0.075) 0.40 (0.016) 0.40 (0.016) 0.96 (0.038)2025 (34) 2.25 (0.089) 0.50 (0.020) 0.40 (0.016) 1.10 (0.043)2026 (78) 3.00 (0.118) 0.33 (0.013) 0.40 (0.016) 1.32 (
