ASTM D3771-2015 Standard Specification for Rubber Seals Used in Concentrating Solar Collectors《太阳能集中式集热器用橡胶密封件的标准规格》.pdf

1、Designation: D3771 03 (Reapproved 2007)D3771 15Standard Specification forRubber Seals Used in Concentrating Solar Collectors1This standard is issued under the fixed designation D3771; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,

2、 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. Scope1.1 This specification covers the general requirements for materials used in rubber seals of concentrating so

3、lar collectors.Particular applications may necessitate other requirements that would take precedence over these requirements when specified.1.2 Design requirement pertains only to permissible deflections of the rubber during thermal expansion or contraction of the sealin use and the tolerances in di

4、mensions of molded and extruded seals.1.3 This specification does not include requirements pertaining to the fabrication or installation of the seals.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 The following safety

5、 hazards caveat pertains only to the test methods portion, Section 9, of this specification:This standarddoes not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of thisstandard to establish appropriate safety and health practices

6、and determine the applicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C661 Test Method for Indentation Hardness of Elastomeric-Type Sealants by Means of a DurometerC717 Terminology of Building Seals and SealantsC719 Test Method for Adhesion and Cohesion of

7、 Elastomeric Joint Sealants Under Cyclic Movement (Hockman Cycle)D395 Test Methods for Rubber PropertyCompression SetD412 Test Methods for Vulcanized Rubber and Thermoplastic ElastomersTensionD865 Test Method for RubberDeterioration by Heating in Air (Test Tube Enclosure)D1149 Test Methods for Rubbe

8、r DeteriorationCracking in an Ozone Controlled EnvironmentD1229 Test Method for Rubber PropertyCompression Set at Low TemperaturesD1349 Practice for RubberStandard Conditions for TestingD1415 Test Method for Rubber PropertyInternational HardnessD1566 Terminology Relating to RubberD2137 Test Methods

9、for Rubber PropertyBrittleness Point of Flexible Polymers and Coated FabricsD2240 Test Method for Rubber PropertyDurometer HardnessD3182 Practice for RubberMaterials, Equipment, and Procedures for Mixing Standard Compounds and Preparing StandardVulcanized SheetsD3183 Practice for RubberPreparation o

10、f Pieces for Test Purposes from ProductsG7 Practice for Atmospheric Environmental Exposure Testing of Nonmetallic MaterialsG151 Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light SourcesG155 Practice for Operating Xenon Arc Light Apparatus for Exposure

11、of Non-Metallic Materials2.2 Other Standards:RMA Handbook Rubber Products: Molded, Extruded, Lathe Cut, and Cellular33. Terminology3.1 Refer to the definitions of terms in Terminology C717 and Terminology D1566.1 This specification is under the jurisdiction of ASTM Committee D11 on Rubber and is the

12、 direct responsibility of Subcommittee D11.37 on Coated Fabrics, RubberThreads and Seals.Current edition approved Nov. 1, 2007June 1, 2015. Published January 2008August 2015. Originally approved in 1979. Last previous edition approved in 20032007 asD3771 03.D3771 03 (2007). DOI: 10.1520/D3771-03R07.

13、10.1520/D3771-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from the Rubber Manufacturers As

14、sociation (RMA), 444 Madison Ave., New York, NY 10022.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes ac

15、curately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United S

16、tates14. Classification4.1 Types:4.1.1 Type C, intended for use in cold climates (below 10C in winter).4.1.2 Type W, intended for use in warm climates (above 10C in winter).4.2 Grades4.2.1 Grade designations represent differing degrees of hardness in accordance withTest Methods D1415 and D2240 as fo

17、llows:4.2.1.1 Grade 2, hardness of 20 6 5.4.2.1.2 Grade 3, hardness of 30 6 5.4.2.1.3 Grade 4, hardness of 40 6 5.4.2.1.4 Grade 5, hardness of 50 6 5.4.2.1.5 Grade 6, hardness of 60 6 5.4.2.1.6 Grade 7, hardness of 70 6 5.4.2.1.7 Grade 8, hardness of 80 6 5.NOTE 1The grade to be used in a particular

18、 application depends on the design of the seal and must be specified by the designer.4.3 Classes:4.3.1 Seals shall be classified as follows:4.3.1.1 Class PS, preformed rubber seal.4.3.1.2 Class SC, sealing compound.NOTE 2Class SC material should not be used in designs where the seal is under mechani

19、cal stress.5. Materials and Manufacture5.1 Resistance to solar radiation can be determined by one of the following:5.1.1 Desert outdoor exposure, in accordance with recommended Practice G7 using the exposure rack at an angle of 45 forunbacked exposure of the specimens. Desert outdoor exposure shall

20、be for at least six months including at least one monthpreceding and following the summer solstice.5.1.2 Xenon arc laboratory exposure, in accordance with recommended Practice G151 and G155 using daylight filters andoperating conditions as described below:5.1.2.1 The irradiance level shall be mainta

21、ined at 0.55 6 0.02 W/(m2nm) at 340 nm at the control point. For equivalent broadband irradiance levels and tolerances at 300 to 400 nm and 300 to 800 nm, consult the manufacturer of the apparatus.5.1.2.2 The default exposure cycle shall be 102 min light only followed by 18 min light plus either wat

22、er spray on the frontsurface or immersion in water. The water spray temperature is typically 21 6 5C, but may be lower if ambient water temperatureis low andspray water can be fresh or recirculated from a holding tank. The temperature of the spray water is uncontrolled andfor fresh water typically r

23、anges between 16 and 26C. Recirculated spray water can be at a higher temperature. Immersion wateris generally in a holding tank is not used to store purified water. The immersion water is kept at a constant temperature, which shallbe less than 40C.for recirculation. The uncontrolled temperature of

24、the recirculated immersion water during operation of theweathering device typically ranges between 45 and 55C.NOTE 3Water spray and immersion in water are different kinds of moisture exposures and may produce different results.5.1.2.3 The uninsulated black panel temperature (BPT) shall be maintained

25、 at 63 6 2.5C at the control point during the dryperiod of exposure to light. For the equivalent insulated black panel temperature (black standard temperature (BST), consult themanufacturer of the apparatus.5.1.2.4 Relative humidity shall be maintained at 60 6 10 % at the control point during the dr

26、y period of exposure to light inxenon arc apparatus that uses water spray for wetting.5.1.2.5 The chamber air temperature shall be maintained at 48 6 2C at the control point in equipment that uses water sprayfor wetting and provides for adjustment of the chamber air temperature.5.1.2.6 The exposure

27、duration shall be by agreement between the parties concerned. The exposure time shall be at least 1000h, but long enough to produce a substantial change in the property of interest in the least stable formulation of the type of materialbeing evaluated.NOTE 4The specified set point is the target cond

28、ition for the control sensor as programmed by the user. When a Standardstandard calls for a particularset point, the user programs the exact number. The tolerances (maximum allowed operational fluctuations) specified with the set point do not imply thatthe user is allowed to program a set point high

29、er or lower than the exact set point specified. Tolerance is determined by the machine variables. Thetolerance specified is the maximum deviationThe operational fluctuations specified are the maximum deviations allowable from the set point at the controlsensor during equilibrium conditions. The mach

30、ine variables determine the operational fluctuations. If under equilibrium conditions they exceed thoseallowed, stop the test and correct the problem before continuing.5.2 After exposure, slight surface chalking and dulling are permitted. Brittleness, cracking, loss of elongation, tackiness, or othe

31、rdeterioration affecting serviceability shall not be permitted.D3771 1526. Requirements6.1 Class PS material shall conform to the requirements given in Table 1.6.2 Class SC material shall conform to the requirements given in Table 2.7. Dimensions7.1 The design of the seal shall not permit the rubber

32、 to deflect more than 25 % in any direction during thermal expansion andcontraction of the solar collector.NOTE 5If the thermal coefficient of linear expansion for the rubber is not known, a value of 0.0003/K may be assumed for design purposes.7.2 The tolerances in dimensions shall conform to the fo

33、llowing designations in the RMA Handbook:7.2.1 Molded Seals:7.2.1.1 Commercial DimensionsRMA-F3-T.032.7.2.1.2 Critical DimensionsRMA-F3-T.032.7.2.2 Extruded Seals:7.2.2.1 Commercial DimensionsRMA-F3.8. Workmanship, Finish, and Appearance8.1 Class PS seals shall be free of blisters, checks, cracks, a

34、nd other imperfections that can affect their ability to make ormaintain a watertight seal.8.2 Class SC material shall be uniform in composition and be free of defects that may affect serviceability, such as partiallyvulcanized lumps.9. Test Methods9.1 Class PS MaterialPrepare the specimens in accord

35、ance with Practice D3183 and test the specimens in accordance withthe test methods given in Table 1. For control of production, specimens may be taken from standard test sheets prepared inaccordance with Practice D3182, using the same unvulcanized material used to prepare the seals and vulcanizing t

36、he material atthe same temperature used for the seals to an equivalent state of vulcanization.9.2 Class SC MaterialPrepare five sheets approximately 150 by 150 by 2 mm in accordance with the instructions suppliedwith the sealing material. Also, prepare five adhesion specimens in accordance with Test

37、 Method C719. Preferably, prepare eachsheet and adhesion specimen from material in a different container. Condition the sheets and adhesion specimens for 14 days ata temperature of 23C and relative humidity of 50 %. Test the material in accordance with the test methods given in Table 2.9.3 Determine

38、 volatiles lost from the difference in mass of the specimens before and after heating for 166 h at the temperaturegiven in Table 1 or Table 2 and in accordance with Test Method D865.TABLE 1 Requirements for Class PS Material Used to Seal Solar Collectorscolwidth=“1.06in“/COLSPECProperty Grade ASTM3

39、4 5 6 7 8Ultimate elongation, min, % 350 300 250 200 150 100 D412Compression set, max, %:after 70 h at MSTA 30 30 30 30 30 30 D395Bafter 166 h at 10C 60 60 60 60 60 60 D1229CResistance to heating (for 166 h at MSTA ): D865Hardness change, max 10 10 10 10 10 10 D1415 orD2240Ultimate elongation change

40、, max, % 30 30 30 30 30 30 D412Tensile strength change, max, % 20 20 20 20 20 20 D412Volatiles lost, max, % 1 1 1 1 1 1 see 9.3Volatiles condensible, max, % 0.1 0.1 0.1 0.1 0.1 0.1 see 9.4Resistance to ozone, 100 mPa,D for 166 h at40Cno cracking D1149Resistance to low temperature, Type C only,max, C

41、40 40 40 40 40 40 D2137Resistance to Outdoor or Xenon Arc Expo-sure No brittleness, cracking, tackiness, or other deterioration affecting serviceability.G7 or G155A The test temperature is based on the maximum service temperature (MST) which normally occurs when the collector is under stagnation con

42、ditions and is receiving themaximum radiation flux to which it will be exposed. The test temperature listed in Practice D1349 that is between 25 and 49C above the maximum service temperatureis used. These temperatures are: 150, 175, 200, 225, and 250C.B Method B.C Set to be measured at 10 s after re

43、lease. Lubricated plates or polytetrafluoroethylene film is recommended if the rubber adheres to the metal compression plates duringthe test.D 100 mPa of ozone partial pressure is equivalent to 100 pphm at standard atmospheric pressure (100 kPa). See new terminology on ozone content expressions desc

44、ribedin Test Methods D1149.D3771 1539.4 Determine volatiles condensible at 23C from the difference in mass of the outlet tubes before and after heating thespecimens for 166 h at the temperature given in Table 1 or Table 2 and in accordance with Test Method D865. If necessary, coolthe exposed portion

45、 of the outlet tube with a stream of air to maintain a temperature of 23 6 2C. If any volatiles condense onthe inlet tube or other parts of the apparatus, add the mass of this condensed material to the mass of the material on the outlet tube.10. Inspection and Rejection10.1 Class PS MaterialManufact

46、urers of preformed seals may use their quality-control systems for production inspection toensure the seals conform with this specification, provided appropriate records are kept. In case of dispute regarding the quality ofa delivered product, a sample of five seals shall be taken from the lot and t

47、ested for compliance with this specification. If one ofthe five seals does not conform, a second sample of five seals may be taken and tested. If two or more of the ten seals do notconform, the lot may be rejected.10.2 Class SC MaterialManufacturers may use their quality-control systems to ensure pr

48、oduction conforms with thisspecification. In case of dispute regarding the quality of a delivered product, five test sheets and five adhesion specimens shall beprepared, preferably from five different packages, in accordance with the instructions supplied with the sealing material. If one ofthe five

49、 sheets or adhesion specimens does not conform, an additional five sheets or adhesion specimens may be prepared andtested. If two or more of the ten sheets or adhesion specimens do not conform, the lot may be rejected.11. Product Marking11.1 The following information shall be marked either on the seal, packaging, label, or tag:11.1.1 Name, brand, or trademark of the manufacturer,11.1.2 Type and grade,11.1.3 Compliance with Specification D3771, and11.1.4 Other information required by the manufacturer or purchaser.12. Packag