1、Designation: D 3903 03Standard Specification forRubber Seals Used in Air-Heat Transport of Solar EnergySystems1This standard is issued under the fixed designation D 3903; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、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.1. Scope1.1 This specification covers the general requirements forthe rubber seals used in solar energy systems employingair-heat
3、 transport. Examples are duct and damper seals. Par-ticular applications may necessitate other requirements thatwould take precedence over these requirements when speci-fied.NOTE 1Rubber seals for the collector are covered in SpecificationsD 3667 and D 3771.21.2 Design requirement pertains only to p
4、ermissible deflec-tions of the rubber during thermal expansion or contraction ofthe seal in use and the tolerances in dimensions of molded andextruded seals.1.3 This specification does not include requirements per-taining to the fabrication or installation of the seals.1.4 The values stated in SI un
5、its are to be regarded as thestandard.1.5 The following safety hazards caveat pertains only to thetest methods portion, Section 10, of this specification: Thisstandard does not purport to address the safety concernsassociated with its use. It is the responsibility of the user of thisstandard to esta
6、blish appropriate safety and health practicesand determine the applicability of regulatory limitations priorto use.2. Referenced Documents2.1 ASTM Standards:C 661 Test Method for Indentation Hardness ofElastomeric-Type Sealants By Means of a Durometer3C 717 Terminology of Building Seals and Sealants
7、3C 719 Test Method for Adhesion and Cohesion of Elasto-meric Joint Sealants Under Cyclic Movement (HockmanCycle)3D 395 Test Methods for Rubber PropertyCompressionSet4D 412 Test Methods for Vulcanized Rubber and Thermo-plastic ElastomersTension4D 865 Test Method for RubberDeterioration by Heatingin A
8、ir (Test Tube Enclosure)4D 1149 Test Method for Rubber DeteriorationSurfaceOzone Cracking in a Chamber4D 1229 Test Method for Rubber PropertyCompressionSet at Low Temperatures4D 1349 Practice for RubberStandard Temperatures forTesting4D 1415 Test Method for Rubber PropertyInternationalHardness4D 156
9、6 Terminology Relating to Rubber4D 2137 Test Methods for Rubber PropertyBrittlenessPoint of Flexible Polymers and Coated Fabrics4D 2240 Test Method for Rubber PropertyDurometerHardness4D 3182 Practice for RubberMaterials, Equipment, andProcedures for Mixing Standard Compounds and Prepar-ing Standard
10、 Vulcanized Sheets4D 3183 Practice for RubberPreparation of Pieces for TestPurposes From Products4D 3667 Specification for Rubber Seals Used in Flat-PlateSolar Collectors2D 3771 Specification for Rubber Seals Used in Concentrat-ing Solar Collectors2G 7 Practice for Atmospheric Environment Exposure T
11、est-ing of Nonmetallic Materials5G 151 Practice for Exposing Nonmetallic Materials in Ac-celerated Test Devices that Use Laboratory Light Sources5G 155 Practice for Operating Xenon Arc Light Apparatusfor Exposure of Nonmetallic Materials52.2 Other Standards:RMA HandbookRubber Products: Molded, Extru
12、ded,Lathe Cut, and Cellular (Third Edition)63. Terminology3.1 Definitions Refer to the definitions of terms in Termi-nology C 717 and Terminology D 1566.1This specification is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.36 on Seals.Curre
13、nt edition approved June 10, 2003. Published June 2003. Originallyapproved in 1980. Last previous edition approved in 2000 as D 3903-00.2Annual Book of ASTM Standards, Vol 09.02.3Annual Book of ASTM Standards, Vol 04.07.4Annual Book of ASTM Standards, Vol 09.01.5Annual Book of ASTM Standards, Vol 14
14、.04.6Available from the Rubber Manufacturers Association (RMA), 1901 Pennsyl-vania Ave. N.W., Washington, DC 20006.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Classification4.1 Types:4.1.1 Type C, intended for use in cold clim
15、ates(below 10C in winter).4.1.2 Type W, intended for use in warm climates(above 10C in winter).4.2 GradesGrade designations represent differing degreesof hardness as follows:4.2.1 Grade 2, hardness of 20 6 5.4.2.2 Grade 3, hardness of 30 6 5.4.2.3 Grade 4, hardness of 40 6 5.4.2.4 Grade 5, hardness
16、of 50 6 5.4.2.5 Grade 6, hardness of 60 6 5.4.2.6 Grade 7, hardness of 70 6 5.4.2.7 Grade 8, hardness of 80 6 5.NOTE 2The grade to be used in a particular application depends onthe design of the seal and must be specified by the designer.4.3 ClassesSeals shall be classified as follows:4.3.1 Class PS
17、, preformed rubber seal.4.3.2 Class SC, sealing compound.NOTE 3Class SC material should not be used in designs where theseal is under mechanical stress.5. Ordering Information5.1 Orders for material under this specification shall includethe following information:5.1.1 Type,5.1.2 Grade,5.1.3 Class,5.
18、1.4 Shape and dimensions,5.1.5 Quantity,5.1.6 ASTM designation and year of issue, and5.1.7 Other requirements.6. Materials and Manufacture6.1 Resistance to solar radiation can be determined by oneof the following:6.1.1 Desert outdoor exposure, in accordance with recom-mended Practice G 7 using the e
19、xposure rack at an angle of 45for unbacked exposure of the specimens. Desert outdoorexposure shall be for at least six months including at least onemonth preceding and following the summer solstice.6.1.2 Xenon arc laboratory exposure, in accordance withrecommended Practice G 151 and G 155 using dayl
20、ight filtersand operating conditions as described below:6.1.2.1 The irradiance level shall be maintained at 0.55 60.02 W/(m2nm) at 340 nm at the control point. For equivalentbroad band irradiance levels and tolerances at 300 to 400 nmand 300 to 800 nm, consult the manufacturer of the apparatus.6.1.2
21、.2 The default exposure cycle shall be 102 min lightonly followed by 18 min light plus either water spray on thefront surface or immersion in water. The water spray tempera-ture is typically 21 6 5C, but may be lower if ambient watertemperature is low and a holding tank is not used to storepurified
22、water. The immersion water is kept at a constanttemperature, which shall be less than 40C.NOTE 4Water spray and immersion in water are different kinds ofmoisture exposures and may produce different results.6.1.2.3 The uninsulated black panel temperature (BPT) shallbe maintained at 63 6 2.5C at the c
23、ontrol point during the dryperiod of exposure to light. For the equivalent insulated blackpanel temperature (black standard temperature (BST), consultthe manufacturer of the apparatus.6.1.2.4 Relative humidity shall be maintained at 60 6 10 %at the control point during the dry period of exposure to
24、lightin xenon arc apparatus that uses water spray for wetting.6.1.2.5 The chamber air temperature shall be maintained at48 6 2C at the control point in equipment that uses waterspray for wetting and provides for adjustment of the chamberair temperature.6.1.2.6 The exposure duration shall be by agree
25、ment be-tween the parties concerned. The exposure time shall be at least1000 h, but long enough to produce a substantial change in theproperty of interest in the least stable formulation of the type ofmaterial being evaluated.NOTE 5The set point is the target condition for the control sensor asprogr
26、ammed by the user. When a Standard calls for a particular set point,the user programs the exact number. The tolerances specified with the setpoint do not imply that the user is allowed to program a set point higheror lower than the exact set point specified. Tolerance is determined by themachine var
27、iables. The tolerance specified is the maximum deviationallowable from the set point at the control sensor during equilibriumconditions.6.2 After exposure, slight surface chalking and dulling arepermitted. Brittleness, cracking, loss of elongation, tackiness,or other deterioration affecting servicea
28、bility shall not bepermitted.7. Requirements7.1 Class PS material shall conform to the requirementsgiven in Table 1.7.2 Class SC material shall conform to the requirementsgiven in Table 2.8. Dimensions8.1 The design of the seal shall not permit the rubber todeflect more than 25 % in any direction du
29、ring thermalexpansion and contraction of the solar collector.NOTE 6If the thermal coefficient of linear expansion for the rubber isnot known, a value of 0.0003/K may be assumed for design purposes.8.2 The tolerances in dimensions of molded seals shallconform to the following designations in the RMA
30、Handbook:8.2.1 Molded Seals:8.2.1.1 Commercial DimensionsRMA -F3-T.032.8.2.1.2 Critical DimensionsRMA -F3-T.032.8.2.2 Extended Seals:8.2.2.1 Commercial DimensionsRMA -F3.9. Workmanship, Finish, and Appearance9.1 Class PS seals shall be free of blisters, checks, cracks,and other imperfections that ca
31、n affect their ability to make ormaintain a tight seal.9.2 Class SC material shall be uniform in composition andbe free of defects that may affect serviceability.D390303210. Test Methods10.1 Class PS MaterialPrepare the specimens as pre-scribed in Recommended Practice D 3183 and test the materialin
32、accordance with the test methods given in Table 1. Forcontrol of production, specimens may be taken from standardtest sheets prepared in accordance with Practice D 3182, usingthe same unvulcanized material used to prepare the seals andvulcanizing the material at the same temperature used for theseal
33、s to an equivalent state of vulcanization.10.2 Class SC MaterialPrepare five sheets approximately150 by 150 by 2 mm in accordance with the instructionssupplied with the sealing material. Also, prepare five adhesionspecimens in accordance with Test Method C 719. Preferably,prepare each sheet and adhe
34、sion specimen from material in adifferent container. Condition the sheets and adhesion speci-mens for 14 days at a temperature of 23 6 2C and relativehumidity of 50 6 5 %. Test the material in accordance with thetest methods given in Table 2.10.3 Determine the volatiles lost from the difference in m
35、assof the specimens before and after heating for 166 h at thetemperature given in Table 1 or Table 2 and in accordance withTest Method D 865.11. Inspection and Rejection11.1 Class PS MaterialManufacturers of preformed sealsmay use their quality control systems for production inspectionto assure the
36、seals conform with this specification, providedappropriate records are kept. In case of dispute regarding thequality of a delivered product, a sample of five seals shall betaken from the lot and tested for compliance with this specifi-cation. If one of the five seals does not conform, a secondsample
37、 of five seals may be taken and tested. If two or more ofthe ten seals do not conform, the lot shall be rejected.11.2 Class SC MaterialManufacturers may use their qual-ity control systems to assure production conforms with thisspecification. In case of dispute regarding the quality of adelivered pro
38、duct, five test sheets and five adhesion specimensshall be prepared from five different packages, in accordancewith the instructions supplied with the sealing material. If oneof the five sheets or adhesion specimens does not conform, anadditional five sheets or adhesion specimens may be preparedand
39、tested. If two or more of the ten sheets or adhesionspecimens do not conform, the lot shall be rejected.12. Product Marking12.1 The following information may be marked on eitherthe seal, packaging, label, or tag:12.1.1 Name, brand, or trademark of the manufacturer,12.1.2 Type, grade, and class,12.1.
40、3 Compliance with this standard, Specification D 3903,and12.1.4 Other information required by the manufacturer orthe purchaser.13. Packaging and Package Marking13.1 Material shall be protected by suitable packaging toprevent damage during shipment or storage prior to installationin the solar collect
41、or.TABLE 1 Requirements for Class PS Material Used to Seal Air-Heat Transport SystemsPropertyGradeASTM Method345678Ultimate elongation, min, % 350 300 250 200 150 100 D412Compression set, max, %:after 70 h at 125C 30 30 30 30 30 30 D395Aafter 166 h at 10C 60 60 60 60 60 60 D1229BResistance to heatin
42、g (166 h at 125C):CD865Hardness change, max 10 10 10 10 10 10 D1415 or D2240Ultimate elongation change, max, % 30 30 30 30 30 30 D412Volatiles lost, max, % 222222se10.3Resistance to ozone, 100 mPa,Dfor 166 h at 40C no cracking D1149Resistance to low temperature, D2137Type C only, max, C 40 40 40 40
43、40 40AMethod B.BSet to be measured at 10 s after release. Lubricated plates or polytetrafluoroethylene film is recommended if the rubber adheres to the metal compression plates duringtest.CThe test temperature of 125C should cover most applications in air ducts of solar energy systems. A seal in an
44、air-heat transport system operating at temperaturesabove 100C should be tested at a standard test temperature listed in Practice D 1349 at least 25C above the maximum temperature in service. The higher testtemperatures are: 150, 175, 200, 225, and 250C.D100 mPa of ozone partial pressure is equivalen
45、t to 100 pphm at standard atmospheric pressure (100 kPa). See new terminology on ozone content expressionsdescribed in Test Method D 1149.TABLE 2 Requirements for Class SC Material Used to Seal Flat-Plate Solar CollectorsPropertyGradeASTMMethod234Ultimate elongation, min, % 200 150 100 D412Resistanc
46、e to heating (166 h at100C):D865Hardness change, max 10 10 10 C661Ultimate elongation change,max, %30 30 30 D412Volatiles lost, max, % 2 2 2 see 10.3Resistance to ozone, 100 mPa,Afor 166 h at 40Cno cracking D1149Resistance to low temperature, D2137Type C only, max, C 40 40 40Adhesion loss, max, cm2B
47、9 9 9 C719CA100 mPa of ozone partial pressure is equivalent to 100 pphm at standardatmospheric pressure (100 kPa). See new terminology on ozone content expres-sions described in Test Method D 1149.BThe combined loss in bond and cohesion areas for the three specimens testedshall not exceed 9 cm2.CThe
48、 temperature in 6.3 of Test Method C 719 shall be modified to 100C.D390303314. Keywords14.1 air-heat transport; rubber seals; solar energy systemsASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of
49、 this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will rec
