ASTM_D_3771_-_15.pdf

Designation:D377115Standard 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,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 formaterials used in rubber seals of concentrating solar collectors.Particular applications may necessitate other requirements thatwould take precedence over these requirements when speci-fied.1.2 Design requirement pertains only to permissible 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 units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 The following safety hazards caveat pertains only to thetest methods portion,Section 9,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 regulatory limita-tions 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 Elasto-meric Joint Sealants Under Cyclic Movement(HockmanCycle)D395 Test Methods for Rubber PropertyCompression SetD412 Test Methods for Vulcanized Rubber and Thermoplas-tic ElastomersTensionD865 Test Method for RubberDeterioration by Heating inAir(Test Tube Enclosure)D1149 Test Methods for Rubber DeteriorationCracking inan Ozone Controlled EnvironmentD1229 Test Method for Rubber PropertyCompression Setat Low TemperaturesD1349 Practice for RubberStandard Conditions for Test-ingD1415 Test Method for Rubber PropertyInternationalHardnessD1566 Terminology Relating to RubberD2137 Test Methods for Rubber PropertyBrittleness Pointof Flexible Polymers and Coated FabricsD2240 Test Method for Rubber PropertyDurometer Hard-nessD3182 Practice for RubberMaterials,Equipment,and Pro-cedures for Mixing Standard Compounds and PreparingStandard Vulcanized SheetsD3183 Practice for RubberPreparation of Pieces for TestPurposes from ProductsG7 Practice for Atmospheric Environmental Exposure Test-ing of Nonmetallic MaterialsG151 Practice for Exposing Nonmetallic Materials inAccel-erated Test Devices that Use Laboratory Light SourcesG155 Practice for Operating Xenon Arc Light Apparatus forExposure 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 C717and Terminology D1566.4.Classification4.1 Types:4.1.1 Type C,intended for use in cold climates(be-low 10C in winter).1This specification is under the jurisdiction ofASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.37 on Coated Fabrics,RubberThreads and Seals.Current edition approved June 1,2015.Published August 2015.Originallyapproved in 1979.Last previous edition approved in 2007 as D3771 03(2007).DOI:10.1520/D3771-15.2For 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.3Available from the Rubber Manufacturers Association(RMA),444 MadisonAve.,New York,NY 10022.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.1.2 TypeW,intendedforuseinwarmclimates(above 10C in winter).4.2 Grades4.2.1 Grade designations represent differing degrees ofhardness in accordance with Test Methods D1415 and D2240as follows: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.NOTE1The grade to be used in a particular application depends on thedesign 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.NOTE2Class SC material should not be used in designs where theseal is under mechanical stress.5.Materials and Manufacture5.1 Resistance to solar radiation can be determined by oneof the following:5.1.1 Desert outdoor exposure,in accordance with recom-mended Practice G7 using the exposu