1、Designation: F876 17 An American National StandardStandard Specification forCrosslinked Polyethylene (PEX) Tubing1This standard is issued under the fixed designation F876; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers crosslinked polyethylene(PEX) tubing that incorporates an optional polymeric inner,middle
3、or outer layer and that is outside diameter controlled,made in nominal SDR9 tubing dimension ratios except wherenoted, and pressure rated for water at three temperatures (seeAppendix X1). Included are requirements and test methods formaterial, workmanship, dimensions, burst pressure, hydrostaticsust
4、ained pressure, excessive temperature and pressure, envi-ronmental stress cracking, stabilizer functionality, bent-tubehydrostatic pressure, oxidative stability in potable chlorinatedwater, and degree of crosslinking. Requirements for tubingmarkings are also given. The components covered by thisspec
5、ification are intended for use in, but not limited to,residential and commercial, hot- and cold-potable water distri-bution systems, reclaimed water, fire protection, municipalwater service lines, radiant heating and cooling systems,hydronic distribution systems, snow and ice melting systems,geother
6、mal ground loops, district heating, turf conditioning,compressed air distribution and building services pipe, pro-vided that the PEX tubing covered herein complies withapplicable code requirements.1.2 The text of this specification references notes, footnotes,and appendixes which provide explanatory
7、 material. Thesenotes and footnotes (excluding those in tables and figures) shallnot be considered as requirements of the specification.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided f
8、or information onlyand are not considered standard.1.4 The following safety hazards caveat pertains only to thetest methods portion, Section 7, 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
9、userof this standard to establish appropriate safety, health, andenvironmental practices and determine the applicability ofregulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in th
10、e 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:2D618 Practice for Conditioning Plastics for TestingD792 Test Methods for De
11、nsity and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD1505 Test Method for Density of Plastics by the Density-Gradient TechniqueD1598 Test Method for Time-to-Failure of Plastic PipeUnder Constant Internal PressureD1599 Test Method for Resistance to Short-Time HydraulicPressure o
12、f 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 Content andSwell Ratio
13、of Crosslinked Ethylene PlasticsD2837 Test Method for Obtaining Hydrostatic Design Basisfor Thermoplastic Pipe Materials or Pressure Design Basisfor Thermoplastic Pipe ProductsD3895 Test Method for Oxidative-Induction Time of Poly-olefins by Differential Scanning CalorimetryF412 Terminology Relating
14、 to Plastic Piping SystemsF1281 Specification for Crosslinked Polyethylene/Aluminum/Crosslinked Polyethylene (PEX-AL-PEX)Pressure PipeF2023 Test Method for Evaluating the Oxidative Resistanceof Crosslinked Polyethylene (PEX) Pipe, Tubing andSystems to Hot Chlorinated Water1This specification is unde
15、r the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.26 on OlefinBased Pipe.Current edition approved Aug. 1, 2017. Published September 2017. Originallyapproved in 1984. Last previous edition approved 2015 as F876 15a. DOI:10.1520/F087
16、6-17.2For 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 this historical standard i
17、s referenced onwww.astm.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 princi
18、ples 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.1F2657 Test Method for Outdoor Weathering Exposure ofCrosslinked Polyethylene
19、 (PEX) Tubing2.2 ANSI Standard:B36.10 Standards Dimensions of Steel Pipe (IPS)42.3 Federal Standard:FED-STD-123 Marking for Shipment (Civil Agencies)52.4 Military Standard:MIL-STD-129 Marking for Shipment and Storage52.5 NSF Standard:NSF/ANSI 14 for Plastic Piping Components and RelatedMaterials62.6
20、 ISO Standards:4ISO 1167 Thermoplastics pipes, fittings and assemblies forthe conveyance of fluids - Determination of the resistanceto internal pressure - Part 1: General methodISO 13760 Plastics pipes for the conveyance of fluids underpressure - Miners rule - Calculation method for cumu-lative dama
21、geISO R 161-1690 Pipes of Plastic Materials for the Transportof Fluids (Outside Diameters and Nominal Pressures) Part1, Metric Series2.7 PPI Standard:7PPI TR-3 Policies and Procedures for Developing Hydro-static Design Basis (HDB), Hydrostatic Design Stresses(HDS), Pressure Design Basis (PDB), Stren
22、gth DesignBasis (SDB), Minimum Required Strength (MRS)Ratings, and Categorized Required Strength (CRS) forThermoplastic Piping Materials or PipePPI TR-4 PPI Listing of Hydrostatic Design Basis (HDB),Strength Design Basis (SDB), Pressure Design Basis(PDB) and Minimum Required Strength (MRS) Ratingsfo
23、r Thermoplastic Piping Materials or Pipe3. Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology F412, and abbreviations are in accordance with Termi-nology D1600, unless otherwise specified. The abbreviation forcrosslinked polyethylene is PEX. Plastic tubing denotes aparticular
24、diameter schedule of plastic pipe in which outsidediameter of the tubing is equal to the nominal size plus18 in.Plastic pipe outside diameter schedule conforms to ANSIB36.10.3.2 Definitions of Terms Specific to This Standard:3.2.1 crosslinked polyethylenea polyethylene material thathas undergone a c
25、hange in molecular structure through pro-cessing whereby a majority of the polymer chains are chemi-cally linked.3.2.2 hydrostatic design stress (HDS)the estimated maxi-mum tensile stress the material is capable of withstandingcontinuously with a high degree of certainty that failure of thetube will
26、 not occur. This stress is circumferential when internalhydrostatic water pressure is applied. The HDS is equal to thehydrostatic design basis (HDB) times the design factor (DF)for water. For this standard, the design factor is equal to 0.50.4Available from American National Standards Institute (ANS
27、I), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5DLA Document Services Building 4/D 700 Robbins Avenue Philadelphia, PA19111-5094 http:/quicksearch.dla.mil/6Available from NSF International, P.O. Box 130140, 789 N. Dixboro Rd., AnnArbor, MI 48113-0140, http:/www.nsf.org.7Plastic
28、s Pipe Institute (PPI), 105 Decker Court, Suite 825 Irving TX, 75062.http:/www.plasticpipe.orgTABLE 1 Thermoplastic Tubing Material Designation Code Cells for SDR9 PEXProperty Standard 0 1 2 3 4 5 6 7 8 9ChlorineResistanceF2023 Not testedor rated75 %at 73Fand 25 %at 140FReserved 50 %at 73Fand 50 %at
29、 140FReserved 100 %at 140F. . . .Minimum UVResistanceF2657 Not testedor rated1 month 3 months 6 months . . . . . .HDSfor water at73F. . . . . . . 630 . 800 .Thermoplastic Tubing Material Designation CodeFor example ASTM F876 PEX tubing marked with the material designation code PEX 1106 is a PEX tubi
30、ngmeeting the chlorine resistance requirement for 25% of the time at 140F and 75% of the time at 73F having a Minimum UV resistance of 1 month and having an HDSfor water at 73F of 630psi (HDB of 1250 psi).F876 172HDS 5 HDB 3DF5HDB 30.50 for this standard!3.2.3 hydrostatic design basis (HDB)one of a
31、series ofestablished stress values (specified in Test Method D2837) fora plastic compound obtained by categorizing the long-termhydrostatic strength determined in accordance with TestMethod D2837.3.2.3.1 DiscussionA listing of HDB and HDS values arecontained in PPI publication PPI TR4.3.2.4 pressure
32、 rating (PR)the estimated maximum waterpressure the tube is capable of withstanding continuously witha high degree of certainty that failure of the tube will not occur.3.2.5 relation between dimensions, hydrostatic designstress, and pressure ratingthe following expression, com-monly known as the ISO
33、 equation,8is used in this specificationto relate dimensions, hydrostatic design stress, and pressurerating:2S/P 5 DO/t! 2 1 (1)or2S/P 5 R 2 1where:S = hydrostatic design stress, psi (or MPa),P = pressure rating, psi (or MPa),DO= average outside diameter, in. (or mm),t = minimum wall thickness, in.
34、(or mm), andR = standard dimension ratio, SDR.3.2.6 standard dimension ratio (SDR)the ratio of outsidediameter to wall thickness. For PEX tubing, it is calculated bydividing the average outside diameter of the tubing in inches orin millimetres by the minimum wall thickness in inches ormillimetres. I
35、f the wall thickness calculated by this formula isless than 0.070 in. (1.78 mm) it shall be arbitrarily increased to0.070 in. except for sizes516 in. and smaller, as specified inTable 3. The SDR values shall be rounded to the nearest 0.5.3.2.7 thermoplastic tubing materials designation codeThetubing
36、 material designation code shall consist of the abbrevia-tion for the type of plastic (PEX) followed by four Arabicnumerals two to describe the short-term properties, inaccordance with theASTM standard being referenced, and twoto designate the hydrostatic design stress when tested in waterat 73F (23
37、C) in units of 100 psi, with any decimal figuresdropped. See Table 1.3.2.7.1 DiscussionThe first digit is for chlorine resistancetested in accordance with Test Method F2023.8ISO R161-1690.TABLE 2 Outside Diameters and Tolerances for SDR9 PEX TubingNominal TubingSizeAverage OutsideDiameterTolerances
38、for Average Diameter Out-of-RoundnessAin. (mm) in. (mm) in. (mm)18 0.250 (6.35) 0.003 (0.08) 0.008 (0.20)14 0.375 (9.52) 0.003 (0.08) 0.008 (0.20)516 0.430 (10.92) 0.003 (0.08) 0.008 (0.20)38 0.500 (12.70) 0.003 (0.08) 0.012 (0.32)12 0.625 (15.88) 0.004 (0.10) 0.016 (0.40)58 0.750 (19.05) 0.004 (0.1
39、0) 0.016 (0.40)34 0.875 (22.22) 0.004 (0.10) 0.016 (0.40)1 1.125 (28.58) 0.005 (0.12) 0.020 (0.48)114 1.375 (34.92) 0.005 (0.12) 0.020 (0.48)112 1.625 (41.28) 0.006 (0.16) 0.024 (0.60)2 2.125 (53.98) 0.006 (0.16) 0.030 (0.76)212 2.625 (66.68) 0.007 (0.18) 0.038 (0.95)3 3.125 (79.38) 0.008 (0.20) 0.0
40、45 (1.14)312 3.625 (92.08) 0.008 (0.20) 0.046 (1.16)4 4.125 (104.78) 0.009 (0.23) 0.052 (1.32)412 4.625 (117.48) 0.009 (0.23) 0.059 (1.49)5 5.125 (130.18) 0.010 (0.25) 0.065 (1.65)6 6.125 (155.58) 0.011 (0.28) 0.072 (1.83)AThe Out-of-Roundness specification applies only to tubing prior to coiling.TA
41、BLE 3 Wall Thickness and Tolerances for SDR9 PEX TubingANominal TubingSizeMinimum WallThicknessTolerancein. (mm) in. mm18 0.047B(1.19)B+0.007 (+0.18)14 0.062B(1.57)B+0.010 (+0.25)516 0.064B(1.63)B+0.010 (+0.25)38 0.070B(1.78)B+0.010 (+0.25)12 0.070B(1.78)B+0.010 (+0.25)58 0.083 (2.12) +0.010 (+0.25)
42、34 0.097 (2.47) +0.010 (+0.251 0.125 (3.18) +0.013 (+0.33)114 0.153 (3.88) +0.015 (+0.38112 0.181 (4.59) +0.019 (+0.48)2 0.236 (6.00) +0.024 +0.61)212 0.292 (7.41) +0.030 (+0.76)3 0.347 (8.82) +0.033 (+0.84)312 0.403 (10.23) +0.035 (+0.89)4 0.458 (11.64) +0.040 (+1.02)412 0.514 (13.05) +0.045 (+1.14
43、)5 0.569 (14.46) +0.050 (+1.27)6 0.681 (17.29) +0.060 (+1.52)AThe minimum is the lowest wall thickness of the pipe at any cross section. Themaximum permitted wall thickness, at any cross section, is the minimum wallthickness plus the stated tolerance. All tolerances are on the plus side of theminimu
44、m requirement.BFor nominal tubing sizes of12 and below, wall thickness minimums are notfunctions of SDR.F876 173(1) A digit “0” indicates that the PEX tubing either has notbeen tested for chlorine resistance or that the PEX tubing doesnot meet the minimum requirement for chlorine resistance.(2) A di
45、git “1” indicates the PEX tubing has been testedand meets the requirement of 6.9 for minimum chlorineresistance at the end use condition of 25% at 140F (60C) and75% at 73F (23C).(3) A digit “2” is reserved for future application.(4) A digit “3” indicates that the PEX tubing has beentested and meets
46、the requirement of 6.9 for minimum chlorineresistance at end use condition of 50% at 140F and 50% at73F.(5) A digit “4” is reserved for future application.(6) A digit “5” indicates that the PEX tubing has beentested and meets the requirement of 6.9 for minimum chlorineresistance at end use condition
47、s of 100% of the time at 140F3.2.7.2 DiscussionThe second digit is for demonstratedUV resistance of PEX material when tested in accordance withTest Method F2657. For PEX tubing with the first digit of thematerial designation code equal to 1, 3, or 5 the second digitshall be one of the classification
48、 digits listed in Table 1 for theNominal Exposure Time Period from Table 1 in Test MethodF2657 where the decreased average failure time from 10.3 ofTest Method F2657 is less than or equal to 21%. For PEXtubing with the first digit of the material designation code equalto 0, the second digit shall be
49、 one of the classification digitsfrom Table 1 for the Nominal Exposure Time Period fromTable 1 of Test Method F2657 where the UV-exposed samplesmeet the requirement of 7.10 Stabilizer Functionality, oralternatively using the criteria for potable water piping found inthe preceding sentence of this clause.3.2.7.3 DiscussionPEX tubing is not designed for outdooruse. Data from short-term exposure testing in accordance withthis test method can be used to judge the relative perfor
