1、Designation: F 2263 07e1An American National StandardStandard Test Method forEvaluating the Oxidative Resistance of Polyethylene (PE)Pipe to Chlorinated Water1This standard is issued under the fixed designation F 2263; the number immediately following the designation indicates the year oforiginal ad
2、option or, in the case of revision, the 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.e1NOTEFootnote 6 was editorially corrected in November 2007.1. Scope1.1 This test
3、 method describes the general requirements forevaluating the long-term, chlorinated water, oxidative resis-tance of polyethylene (PE), used in cold water supply orservice systems by exposure to chlorinated water. This testmethod outlines the requirements of a pressurized flow-throughtest system, typ
4、ical test pressures, test-fluid characteristics,failure type, and data analysis.NOTE 1Other known disinfecting systems (chlorine dioxide, ozone,and chloramine) are currently used for protection of potable water;however, free-chlorine is by far the most common system in use today.Disinfecting systems
5、 other than chlorine have not been evaluated by thismethod.1.2 Guidelines and requirements for test temperatures, testhoop stresses, and other test criteria have been established byprior testing of PE pipe. Other related system components thattypically appear in a PE cold water supply or service sys
6、temcan be evaluated with the PE pipe. When testing PE pipe andfittings as a system, it is recommended that the anticipatedend-use fitting type(s) and material(s) be included in the testcircuit since it is known that some fitting types and materialscan impact failure times. Specimens used shall be re
7、presenta-tive of the piping product(s) and material(s) under investiga-tion.NOTE 2The procedures described in this test method (with somemodifications of test temperatures or stresses, or both) have been used toevaluate pipes manufactured from polybutylene (PB), crosslinked poly-ethylene (PEX), poly
8、propylene (PP), multilayer (polymer-metal compos-ite), copper, and stainless steel.1.3 This test method is applicable to PE pipe and systemsused for transport of potable water containing free-chlorine fordisinfecting purposes. The oxidizing potential of the test-fluidspecified in this test method ex
9、ceeds that typically found inpotable water systems across the United States.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are for informa-tion only and are not considered standard.1.5 The following precautionary caveat pertains only to thete
10、st method portion, Section 12, 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 regula
11、tory limita-tions prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1600 Terminology for Abbreviated Terms Relating toPlasticsD 2122 Test Method for Determining Dimensions of Ther-moplastic Pipe and FittingsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a
12、 Test MethodF 412 Terminology Relating to Plastic Piping Systems2.2 ISO Standards:ISO 9080 Thermoplastic Pipe for Transport of FluidsMethods of Extrapolation of Hydrostatic Stress RuptureData to Determine the Long Term Strength of Thermo-plastic Pipe32.3 Plastics Pipe Institute (PPI) Document:TN-16
13、Rate Process Method for Projecting Performance ofPolyethylene Piping Components42.4 American Water Works Association (AWWA) Docu-ment:1This test method is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.40 on TestMethods.Curr
14、ent edition approved March 1, 2007. Published April 2007. Originallyapproved in 2003. Last previous edition approved in 2005 as F 226305.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume i
15、nformation, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.4Available from the Plastics Pipe Institute (PPI), 1825 Connecticut Ave NWSuite 680 Washington, DC 20009.1Copyright A
16、STM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.1996 WATER: STATS Survey53. Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology F 412 and abbreviations are in accordance with Termi-nology D 1600, unless otherwise indicated.
17、3.1.1 brittle failure (Stage II), nfailure in the pipe wallthat is characterized by little or no material deformation in thefailure area and is the result of a single crack emanating fromthe interior of the pipe to the outside surface typically resultingin a pinhole leak, see Fig. 1.3.1.2 cold water
18、 supply or service system, na combinationof components such as pipe, fittings, valves, and so forth, thatwhen installed as a complete system, make up the water supplysystem.3.1.3 ductile failure (Stage I), nfailure in the pipe wallthat is characterized by obvious localized deformation of thematerial
19、 visible with the unaided eye, see Fig. 1. Ductilefailures produced with this test method shall not be used fordata analysis.3.1.4 environmental or oxidative failure (Stage III),nfailure in the pipe wall characterized by a large number ofcracks emanating from the interior surface of the pipe wall, s
20、eeFig. 1.3.1.5 long-term oxidative resistance, nthe extrapolatedtime-to-failure prediction as determined by analysis of time-to-failure test data by multiple linear regression utilizing therate process method of PPI TN-16 or three parameter model ofISO 9080.3.1.6 multiple linear regression, na three
21、 or four coeffi-cient mathematical model used to analyze time-to-failure datafrom different temperatures and stresses to extrapolate pro-jected time-to-failure at selected temperatures or stresses.3.1.7 oxidation reduction potential (ORP), noxidationreduction potential (ORP), n-a measure of the tota
22、l oxidizingpower of a solution by means of a platinum-redox electrode.For a further explanation of ORP see Appendix X2.3.1.8 unaided eye, nobservable without visual enhance-ment beyond correction for normal vision.4. Summary of Test Method4.1 The PE pipe/fitting assemblies are exposed to pressur-ize
23、d test-fluid until failure. All time-to-fail data used foranalysis shall be the result of the same failure mode, either allstage II or all stage III. A minimum number of test temperatureand hoop stress conditions are required to allow accurate dataanalysis and time-to-failure extrapolations. If usin
24、g only stageII failure data, no lifetime extrapolations can be made withoutfurther validation.5. Significance and Use5.1 Environment or oxidative time-to-fail data derived fromthis test method, analyzed in accordance with Section 13, aresuitable for extrapolation to typical end-use temperatures andh
25、oop stresses. The extrapolated value(s) provides a relativeindication of the resistance of the tested PE pipe or system tothe oxidative effects of chlorinated water for conditions equiva-lent to those conditions under which the test data wereobtained. The performance of a material or piping productu
26、nder actual conditions of installation and use is dependentupon a number of factors including installation methods, usepatterns, water quality, nature and magnitude of localizedstresses, and other variables of an actual, operating cold watersupply or service system that are not addressed in this tes
27、tmethod. As such, the extrapolated values do not constitute arepresentation that a PE pipe or system with a given extrapo-lated time-to-failure value will perform for that period of timeunder actual use conditions.5.2 This test method has been generally used for evaluatingoxidative (stage III) failu
28、re data. For some systems being testedaccelerated stage II failures can occur. These failures can alsobe analyzed using the regression analysis outlined in Section13. Extrapolation of this data may need to be validated prior tomaking any lifetime predictions.6. Apparatus6.1 Pressurized Flow-Through
29、Test SystemAsystem com-prised of the necessary pump(s), fittings, piping, heaters,sensors, and meters that is capable of maintaining the requiredtest pressures within the tolerance specified in 9.1.3, therequired test temperatures within the tolerance of 9.1.2, andflow the test-fluid through the spe
30、cimens continually at a flowrate within the tolerance specified in 9.1.4. Cyclic pressurevariations, such as those produced by some pumping systems,shall not produce pressure excursions that exceed the tolerancestated in 9.1.3.6.2 Specimen HoldersTest specimens shall be supportedto minimize or elimi
31、nate externally induced stresses. Speci-mens shall be allowed to freely expand bi-directionally.7. Sampling, Test Specimens, and Test Units7.1 SamplingSelect at random, a sufficient amount of pipeto satisfy the specimen requirements of this test method. Whentesting as a system, randomly select a suf
32、ficient quantity offittings.5Available from American Water Works Association (AWWA), 1401 New YorkAve., NW, Suite 640, Washington, DC 20005.FIG. 1 Pictorial Illustration of Failure TypesF226307e127.2 Test Specimen SizeThe recommended minimum pipesize is12 CTS. The PE pipe specimens shall be 12 to 18
33、 in.(300 to 460 mm) in length between fitting closures or betweenfitting joints.7.2.1 Dimensions MeasurementMeasure and record thecritical dimensions for pipe and fittings. For pipe, measure theaverage outside diameter and wall-thickness in accordancewith Test Method D 2122. For fittings, measure th
34、ose dimen-sions critical to the function of the joint, as well as minimumbody wall thickness.7.3 Testing as a SystemWhen testing PE pipe and relatedsystem components (such as fittings) as a system, the othercomponents shall be attached to the PE pipe in the samemanner as in actual service. For fitti
35、ngs, the particular fittingstyle shall be installed in accordance with the manufacturersinstructions or the ASTM specification when applicable.7.4 Minimum Required Test UnitsA minimum of six testunits is required. A test unit is comprised of two or moreindividual time-to-failure data points at the s
36、ame temperatureand hoop stress condition. Obtaining additional data points ateach temperature/hoop stress condition will benefit statisticalreliability of the analysis of the resultant data.7.4.1 Test Unit DistributionTime-to-failure data pointsshall be obtained at 2 test hoop stresses at each of a
37、minimumof 3 test temperatures for a minimum of 12 data points. As analternate, obtain time-to-failure data for the temperature/hoopstress combinations of the three-temperature matrix of PPITN-16, see Note 3. Hoop stresses shall be separated by a least80 psi (0.55 MPa).NOTE 3When using the PPI TN-16
38、matrix, Temperature T3, whichrequires testing at only one stress, refers to the lowest test temperature.7.4.2 Test Temperature SelectionTemperatures of 90C(194F), 80C (176F), and 70C (158F) have been utilized inprior testing of PE, see Note 4.Adjacent test temperatures shallbe separated by at least
39、18F (10C). Other test temperaturesmay be used, but the maximum test temperature shall notexceed 95C (203F).NOTE 4Prior testing indicates that for the test temperatures stated in7.4.2, hoop stresses to yield Stage II or III failures within reasonabletesting times are between 120 psi (830 kPa) and 480
40、 psi (3.31 MPa). Fora true SDR 9 tube, those hoop stresses correspond to test pressures of 30psig (207 kPa) to 120 psig (830 kPa). If a selected test hoop stressproduces Stage I failures, the stress will need to be reduced to produce allStage II or all Stage III failures at all temperatures.7.4.2.1
41、Relationship of Internal Pressure to Hoop StressThe hoop stress in the pipe wall is calculated by the followingexpression, commonly known as the ISO equation:2S/P 5 DR 2 1 (1)or2S/P 5 Do/t! 2 1 (2)where:S = stress in the circumferential or hoop direction, psi(MPa),P = internal pressure, psig (kPa),t
42、 = minimum wall thickness, in. (mm),DR = dimension ratio, DR, andDo= average outside diameter, in. (mm).8. Calibration and Standardization8.1 Measuring EquipmentAll measuring and testingequipment having an effect on the accuracy or validity of thecalibrations or tests shall be calibrated or verified
43、, or both,before being put into service.9. Test Fluid9.1 Internal Test FluidThe test fluid shall be reverseosmosis (RO) or deionized (DI) water prepared in accordancewith 9.1.1.9.1.1 RO or DI Water Test-Fluid PreparationTest fluidprepared from RO or DI water shall have a pH in the rangefrom 6.5 to 8
44、.0 and contain 2.5 ppm to 5 ppm (milligrams perlitre) of free-chlorine. The chosen pH shall be maintained to 60.2 and the chosen free-chlorine concentration shall be main-tained to 6 0.2 ppm. The pH and free-chlorine concentrationcombination shall yield a minimum ORPof 825 mV for the testfluid.9.1.2
45、 Test Fluid Temperature ControlThe test fluid enter-ing each specimen shall be maintained to 61.8F (61C) ofthe test temperature.9.1.3 Pressure ControlThe pressure of the test fluid shallbe maintained to 63 psig (620.69 kPa).9.1.4 Test Fluid Flow RateThe flow rate of the test fluidshall yield a minim
46、um velocity of 0.12 fps (0.04 mps). For thenominal size12 in., SDR 9 tubing, this corresponds to a flowrate of 0.06 gpm (0.23 LPM). The formula used to calculate theflow rates for other sizes and DRs is as follows:pid/2!2* FPS * 7202315 gpm (3)where:id = measured inside diameter of the tubing, in.9.
47、2 Test Fluid Instrument Accuracy:9.2.1 pHThe pH measurement and control instrumentsshall have an accuracy of 0.1 pH or better.9.2.2 Free-ChlorineFree-chlorine content measurementand control instruments shall have an accuracy of 0.1 ppm orbetter.9.2.3 ORPThe ORP measurement and control instru-ments s
48、hall have an accuracy of 610 mV or better.10. External Environment10.1 The exterior environment shall be air and shall bemaintained at the target temperature of the test fluid tempera-ture 64.5F (62.5C). Direct, forced-air heating of the speci-mens shall not be used.11. Specimen Positioning11.1 The
49、specimens can be positioned vertically or horizon-tally. Horizontal positioning requires special attention to insurethat all entrapped air has been removed prior to starting thetest. For vertically positioned specimens, the test fluid shallflow into the specimens from the lower end.F226307e1312. Procedure12.1 Perform the test procedure in accordance with 12.2-12.4 for the test units specified in 7.4 with a test fluid asspecified in Section 9.12.2 After connecting the specimens to the flow-throughapparatus, purge the specimens of all
