ASTM_D_4976_-_12a.pdf

Designation:D497612aStandard Specification forPolyethylene Plastics Molding and Extrusion Materials1This standard is issued under the fixed designation D4976;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.This standard has been approved for use by agencies of the Department of Defense.INTRODUCTIONThis specification is not intended for the selection of materials,but only as a means to call outplastic materials to be used for the manufacture of parts.The selection of these materials is to be madeby personnel with expertise in the plastics field where the environment,inherent properties of thematerials,performance of the parts,part design,manufacturing process,and economics areconsidered.This specification does not specify the source of the resin to be used for the fabricationof any given article.1.Scope*1.1 This specification provides for the identification ofpolyethylene plastics molding and extrusion materials in sucha manner that the supplier and the user can agree on theacceptability of different commercial lots or shipments.Thetests involved in this specification are intended to provideinformation for identifying materials in accordance with thegroups,classes,and grades covered.It is not the function ofthis specification to provide specific engineering data fordesign purposes.1.2 Other requirements necessary to identify particular char-acteristics important to specialized applications shall be agreedupon between the user and the supplier,by using the suffixesgiven in Section 1.3.1.3 Ethylene plastic materials,being thermoplastic,arereprocessable and recyclable(see Note 1).This specificationallows for the use of those ethylene plastic materials,providedthat any specific requirements as governed by the producer andthe end user are met.NOTE1See Guide D7209 for information and definitions related torecycled plastics.1.4 The values stated in SI units are regarded as standard.1.5 The following precautionary caveat pertains to the testmethod portion only,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 regulatory limita-tions prior to use.1.6 For information regarding plastic pipe materials seeSpecification D3350.For information regarding wire and cablematerials,see Specification D1248.NOTE2There is no known ISO equivalent to this standard.2.Referenced Documents2.1 ASTM Standards:2D257 Test Methods for DC Resistance or Conductance ofInsulating MaterialsD568 Method of Test for Burning and/or Extent and Time ofBurning of Flexible Plastics in a Vertical Position(With-drawn 1991)3D618 Practice for Conditioning Plastics for TestingD635 Test Method for Rate of Burning and/or Extent andTime of Burning of Plastics in a Horizontal PositionD638 Test Method for Tensile Properties of PlasticsD790 Test Methods for Flexural Properties of Unreinforcedand Reinforced Plastics and Electrical Insulating Materi-alsD792 Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by DisplacementD883 Terminology Relating to Plastics1This specification is under the jurisdiction of ASTM Committee D20 onPlastics and is the direct responsibility of Subcommittee D20.15 on ThermoplasticMaterials.Current edition approved Aug.1,2012.Published September 2012.Originallyapproved in 1995.Last previous edition approved in 2006 as D4976-06.DOI:10.1520/D4976-12.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 D1238 Test Method for Melt Flow Rates of Thermoplasticsby Extrusion PlastometerD1248 Specification for Polyethylene Plastics ExtrusionMaterials for Wire and CableD1499 Practice for Filtered Open-Flame Carbon-Arc Expo-sures of PlasticsD1505 Test Method for Density of Plastics by the Density-Gradient TechniqueD1531 Test Methods for Relative Permittivity(DielectricConstant)and Dissipation Factor by Fluid DisplacementProceduresD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD1693 Test Method for Environmental Stress-Cracking ofEthylene PlasticsD2565 Practice for Xenon-Arc Exposure of Plastics In-tended for Outdoor ApplicationsD2839 Practice for Use of a Melt Index Strand for Deter-mining Density of PolyethyleneD2951 Test Met