1、Designation: F477 10An American National StandardStandard Specification forElastomeric Seals (Gaskets) for Joining Plastic Pipe1This standard is issued under the fixed designation F477; the number immediately following the designation indicates the year of originaladoption or, in the case of revisio
2、n, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This specification covers
3、 elastomeric seals (gaskets)used to seal the joints of plastic pipe used for gravity,low-pressure, and high-pressure applications. This refers topush-on joints which require no internal or external pressure toeffect the initial seal.1.2 Requirements are given for natural or synthetic rubbergaskets,
4、or a combination of both.1.3 The text of this specification references notes, footnotes,and appendixes which provide explanatory material. Thesenotes and footnotes (excluding those in tables and figures) shallnot be considered as requirements of the specification.1.4 The values stated in inch-pound
5、units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 The following precautionary caveat pertains only to thetest method portion, Section 7, of this specification: Thissta
6、ndard 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 consult and establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Docum
7、ents2.1 ASTM Standards:2D395 Test Methods for Rubber PropertyCompression SetD412 Test Methods for Vulcanized Rubber and Thermo-plastic ElastomersTensionD471 Test Method for Rubber PropertyEffect of LiquidsD518 Test Method for Rubber DeteriorationSurfaceCracking3D573 Test Method for RubberDeteriorati
8、on in an AirOvenD883 Terminology Relating to PlasticsD1149 Test Methods for Rubber DeteriorationCrackingin an Ozone Controlled EnvironmentD1229 Test Method for Rubber PropertyCompression Setat Low TemperaturesD1349 Practice for RubberStandard Temperatures forTestingD1414 Test Methods for Rubber O-Ri
9、ngsD1415 Test Method for Rubber PropertyInternationalHardnessD1566 Terminology Relating to RubberD2240 Test Method for Rubber PropertyDurometerHardnessF913 Specification for Thermoplastic Elastomeric Seals(Gaskets) for Joining Plastic Pipe2.2 NSF Standards:Standard No. 14 for Plastic Piping Componen
10、ts and RelatedMaterials4Standard No. 61 for Drinking Water Systems Components-Health Effects43. Terminology3.1 DefinitionsTerms relating to rubber or elastomer shallbe as defined in Terminology D1566. Terms relating to plasticsshall be as defined in Terminology D883.4. Composition and Manufacture4.1
11、 All gaskets shall be extruded or molded in such amanner that any cross section will be dense, homogeneous, andfree of porosity, blisters, pitting, or other defects that makethem unfit for the use intended. The gasket shall be fabricatedfrom a high-grade elastomer material. The basic polymer shallbe
12、 natural rubber, synthetic rubber, a blend of both, or athermoplastic elastomer, meeting the requirements prescribedin Sections 5 and 6.4.2 Where a splice is used in the manufacture of the gasket,the strength shall be such that the gasket shall withstand 100 %1This specification is under the jurisdi
13、ction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.20 on Joining.Current edition approved March 15, 2010. Published May 2010. Originallypublished as approved in 1976. Last previous edition approved in 2008 asF477 08. DOI: 10.1520/F0477-10.2For r
14、eferenced 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.3Withdrawn. The last approved version of this historical standard i
15、s referencedon www.astm.org.4Available from NSF International, P.O. Box 130140, 789 N. Dixboro Rd., AnnArbor, MI 48113-0140, http:/www.nsf.org.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 19
16、428-2959, United States.elongation over the part of the gasket which includes the splicewith no visible separation of the splice. While in a stretchedposition the gasket shall be rotated in the spliced area aminimum of 180 in each direction in order to inspect forseparation. In addition, any portion
17、 of the splice shall becapable of passing a bend test without visible separation. Thebend test for circular gaskets is defined as wrapping the portionof the unstretched gasket containing the splice a minimum of180 and a maximum of 270 around a rod of a diameter equalto the cross section diameter of
18、the gasket.5. Dimensions and Tolerances5.1 When in its final assembled position, the gasket shall notbe stretched more than 30 % of its original circumference.NOTE 1Excessive stretch may have deleterious effect on rubbergaskets, the minimum stretch compatible with the proper performance ofthe gasket
19、 should be used at all times.5.2 The gaskets shall conform to the dimensions specifiedby the manufacturer of the pipe or fittings, with which thegaskets are to be used, with a Rubber Manufacturers Associa-tion Class 3 tolerance on all cross section dimensions, and61 % on all diametrical dimensions,
20、unless otherwise agreedupon by the pipe or fitting manufacturer and the purchaser.5.3 For molded gaskets or gasket material, the permissibleflash shall be a maximum of +0.032 in. (0.80 mm). Maximummold mismatch shall not exceed 0.010 in. (0.25 mm).6. Physical Requirements6.1 Standard Gasket requirem
21、entsThe sealing portion ofthe gaskets shall comply with the physical requirements listedinTable 1 for thermoset elastomers orTable 2 for thermoplasticelastomers, when tested in accordance with the methods inSection 7.6.1.1 Oil resistant gaskets requirementsThe sealing por-tion of the gaskets shall n
22、ot contain less than 50% by volumeoil resistant polymer and shall meet the physical requirementslisted in Table 3, when tested in accordance with the methodsin Section 7.NOTE 2Some gaskets incorporate a high durometer elastomeric ornonelastomeric, that is, metal or plastic material, as a reinforceme
23、nt orretaining feature, or both. These materials do not alter the physicalproperties of the sealing portion of the gasket and should not be tested assuch, or expected to meet the material requirements listed in Table 1.NOTE 3The gasket manufacturer should be assured that materialsused for retaining
24、or reinforcement, or both, do not encroach upon thesealing surfaces of the gasket, and have physical properties which ensureadequate longevity for the anticipated usage.6.1.2 HardnessThe Type A durometer average hardnessspecified by the manufacturer shall be within the range given inTable 1 and Tabl
25、e 3 for thermoset elastomers or Table 2 forthermoplastic elastomers. Gaskets are required to have theType A durometer hardness specified, 6 5 points.TABLE 1 Physical Requirements for Elastomeric Seals forPlastic PipeTestsLow-HeadApplication(Below 150kPa or 50-ftHead)High-HeadApplication(150 kPa or50
26、-ft Headand Above)Original Properties:Tensile strength, min, psi (MPa) 1200 (8.3) 2000 (13.8)AElongation, min, % 325 400Hardness, Type A durometer 40 to 60 40 to 60Low-temperature hardness, Type A duro-meter, max increase, points15 15Compression set, max % 25 20Ozone resistance no cracks no cracksAc
27、celerated Aging (Air Oven Test):Decrease in tensile strength, max % oforignal15 15Decrease in elongation, max % of original 20 20Hardness, Type A durometer, max increase,points88After Water Immersion:Change in volume max % 5 5AFor EPDM and nitrile seals, tensile strength min. psi (MPa) is 1500 (10.3
28、).TABLE 2 Physical Requirements for Thermoplastic ElastomericSeals for Plastic PipeLow-HeadApplication(Below 150kPa or 50-ftHead)High-HeadApplication(150 kPa or50-ft Headand Above)Original Properties:Tensile strength, min, psi (MPa) 435 (3.0) 500 (3.5)100 % modulus, min, psi (MPa) 200 (1.4) 280 (1.9
29、)Elongation, min, % 350 350Hardness, Type A durometer 40 to 70 40 to 70Low-temperature hardness, Type Adurometer, max increase, points10 10Compression set, max % 25 20Ozone resistance no cracks no cracksAccelerated Aging (Air Oven Test):Decrease in tensile strength, max % oforiginal15 15Decrease in
30、elongation, max % of original 15 15Hardness, Type A durometer, max change,points55After Water Immersion:Change in volume max % 4 4Force DecayRemaining stress, min,%40 50TABLE 3 Physical Requirements for Oil Resistant ElastomericSeals for Plastic PipeLow-HeadApplication(Below 150kPa or 50-ftHead)High
31、-HeadApplication(150 kPa or50-ft Headand Above)Original Properties:Tensile strength, min, psi (MPa) 1200 (8.3) 1500 (10.3)Elongation, min, % 325 350Hardness, Type A durometer 40 to 60 40 to 60Low-temperature hardness, Type Adurometer, max increase, points15 15Compression set, max % 25 20Ozone resist
32、ance no cracks no cracksAccelerated Aging (Air Oven Test):Decrease in tensile strength, max % oforiginal15 15Decrease in elongation, max % of original 20 20Hardness, Type A durometer, max change,points88After Water Immersion:Change in volume max % 10 10Liquid immersion IRM 903 Oil Max %volume change
33、50 50F477 1026.2 Elastomer compounds must be non-crazing to pipe. Thegasket in the cured state shall not cause craze marks, pits, orblisters when in contact with the plastic pipe. Staining of theplastic pipe in the area of gasket contact is acceptable. Test inaccordance with 7.9 to qualify elastomer
34、 compound for pipemade from the plastic polymer in question.6.3 Where the particular joint design utilizing a rubbergasket dictates the use of a lubricant to facilitate assembly, thelubricant shall be of such composition which will in no waydamage the gasket or pipe due to prolonged exposure.7. Test
35、 Methods7.1 Perform laboratory tests to determine the physical prop-erties of the gaskets to be furnished under this specification on:(1) the finished product as supplied, ( 2) test specimens takenfrom the finished product, or ( 3) from specimens of fabricationof the same elastomeric compound, and i
36、n accordance with theappropriate ASTM standard. (See Practice D1349.)7.2 Tensile Strength and ElongationDetermine tensilestrength, 100 % modulus, and elongation in accordance withTest Methods D412 or D1414 for O-rings.7.3 HardnessDetermine the durometer, Type A, of thegasket in accordance with Test
37、Method D2240 or Test MethodsD1414 for O-rings. (See Test Method D1415.)7.4 Low-Temperature HardnessMeasure the durometer,Type A, of the gasket in accordance with Test Method D2240or Test Methods D1414 for O-rings after conditioning for 22 hat +14 6 4F (10 6 2C) to determine the change in hardness.7.
38、5 Compression SetDetermine the compression set inaccordance with Method B ofTest Methods D395 or D1414 forO-rings. Test temperature and time shall be 22 h at 158 64F(70 6 2C ), with a 25 % deflection of the test specimens.(See Test Method D1229.)7.6 Accelerated AgingAge specimens for physical test i
39、naccordance with Test Method D573. (See Test Method D518.)7.6.1 Age physical test specimens for 96 h at 158 6 4F (706 2C).7.7 Water ImmersionDetermine the change in volume inaccordance with Test Method D471 or Test Methods D1414 forO-rings.7.7.1 The temperature shall be 1586 4F (70 6 2C), andthe imm
40、ersion period shall be 48 h.7.7.2 Immediately after removal from the water, blot thespecimens, weigh, and calculate the volume increase in accor-dance with Test Method D471.7.8 Oil ImmersionDetermine resistance to oil by calculat-ing % volume change after immersing product specimen inASTM IRM 903 oi
41、l for 212 6 4F(70hat1006 2 C) inaccordance with Test Method D471.7.9 Ozone ResistanceDetermine the gaskets resistance toozone in accordance with Test Method D1149.7.9.1 Conduct test for 70 h in 50 pphm concentration at 1046 4F (40 6 2C) with specimens stressed to 20 % extension.7.10 Determine elasto
42、mer compound effect on pipe (6.2)bythe following procedure:7.10.1 The specimen shall be a gasket or a part of a gasketthat will fit within the test fixture shown in Fig. 1.7.10.2 The fixture for the test shall be as described for thecompression set test in Method B of Test Methods D395 witha plate o
43、f plastic adjoining the interior surfaces of the com-pression plates (see Fig. 1).7.10.3 Make liner bearing plates of plastic with a minimumwall thickness of 0.120 in. (3.0 mm) to fit the interior surfacesof the fixtures compression plates.7.10.3.1 Form the plastic bearing plate from like plasticmat
44、erial by cutting and pressing pipe at a workable stressre-lieving temperature not to exceed that required to form a gasketrace.7.10.4 Set the test apparatus up as in the compression settest in accordance with Method B of Test Methods D395 withthe plastic bearing plate in place.7.10.5 Age the specime
45、ns under load for 96 h at 158 6 4F(70 6 2C).7.10.6 Let the specimens cool in the fixture for 24 h at 70 to77F (21 to 25C).7.10.7 Upon release, inspect the plastic bearing plate sur-face that has been in contact with the elastomeric compoundfor cracks, craze marks, pits, or blisters (6.2).7.11 Force
46、Decay (Stress Relaxation)Determine forcedecay in accordance with thermoplastic elastomer force decaytest as outlined in Specification F913.FIG. 1 Device for Test of Elastomeric Compound Effect on PlasticF477 1038. Rejection8.1 The rubber gaskets shall be subject to rejection when-ever they show surf
47、ace checking, weathering, or other deterio-ration prior to installation.9. Certification9.1 At the option of the purchaser, certified copies of testreports on the elastomer from which the shipment of gasketswas made shall be furnished by the gasket supplier.10. Storage10.1 The rubber gaskets shall b
48、e stored in a cool, clean,shaded place. The preferred temperature is 70F (21C) orlower.11. Marking11.1 The markings shall include the gasket manufacturersname or symbol, gasket size, and manufacturers code todifferentiate between high- and low-head gaskets.11.2 Any additional marking or color design
49、ation shall be asagreed upon by the pipe and gasket manufacturer.12. Keywords12.1 elastomeric; gaskets; plastic pipe; push-on joint; rub-ber; seals; synthetic; thermoplastaic elastomerSUPPLEMENTARY REQUIREMENTSPOTABLE WATER REQUIREMENTThis requirement applies whenever a Regulatory Authority or user calls for product to be used toconvey or to be in contact with potable water.S1. Products intended for contact with potable water shallbe evaluated, tested and certified for conformance with ANSI/NSF Standard No. 61 or the health eff
