ASTM_D_2433_-_07.pdf

Designation:D2433 07Standard Test Methods forRubber Thread1This standard is issued under the fixed designation D2433;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 These test methods cover the testing of both roundextruded latex and rectangular cut rubber thread products inwhich the base material used in manufacture may be naturalrubber or synthetic rubber,alone or in combination.These testsare to be made only on the bare uncovered rubber thread.1.2 Owing to the comparatively small cross section of thematerial and also because of the unusual conditions of serviceof this material,certain special test methods have been devel-oped and take the place of the tests for other rubber products.1.3 Comparisons may only be made on new rubber threadsor those of identical processing histories.In the interpretationof results from threads which have been subjected to spooling,fabrication,or other process,the previous history is important,and what is known of this and any relaxation treatments usedshould be stated.1.4 The test methods appear in the following sections:SectionsDensity7-11Count12-16Metric Yield(Length per Unit Weight)17-19Tensile Strength20-22Elongation at Break23 and 24Stress at Predetermined Elongation25-27Elongation Under Fixed Force(Method A)28-30Elongation Under Fixed Force(Method B)31-34Stress Retention35-391.5 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1566 Terminology Relating to RubberD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesE171 Specification for Atmospheres for Conditioning andTesting Flexible Barrier Materials3.Significance and Use3.1 For adequate service performance,rubber threads mustbe tested by appropriate test methods.This standard gives anumber of test methods that are known to be important inrubber thread technology.4.Interferences4.1 Samples or test specimens shall not be allowed to comeinto contact with copper,manganese,or their compoundsduring sample preparation or testing.5.Sample Preparation5.1 The samples and test specimens derived therefrom shallbe kept in a relaxed state and conditioned for not less than 16h before testing.The test specimen selected should be clean,dry,and free from any visual defects.6.Test Conditions6.1 The test shall be performed in a standard atmospherehaving a temperature of 23 6 1C(73.4 6 1.8F)and a relativehumidity of 50 6 2%,as defined in Specification E171.DENSITY7.Terminology7.1 Definitions of Terms Specific to This Standard:1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.37 on Coated Fabricsand Rubber Thread.Current edition approved May 1,2007.Published June 2007.Originallyapproved in 1965.Last previous edition approved in 2002 as D2433 93(2002).DOI:10.1520/D2433-07.2For 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.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.NOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest information7.1.1 density of a rubber threadthe mass of a unit volumeof thread measured at a temperature of 23 6 1C(73.461.8F)expressed as megagrams per cubic metre.8.Summary of Test Method8.1 The density of a rubber thread is determined by employ-ing two liquids of known density.These liquids are mixedtogether in such a proportion that,during immersion,a testspecimen of the thread under examination remains suspended,that is,neither floats nor sinks.The density of this mixture ismeasured and this value taken as the density of the specimen.9.Apparatus9.1 Glass Cylinder,having a capacity of about 1000 cm3.9.2 Hydrometer or Hydrostatic Balance(0.001 m3),tomeasure the density of the liquids to an accuracy of not lessthan 0.005 Mg/m3.10.Suitable Mixtures10.1 Most of the rubber threads on the market have adensity in the range from 0.90 to 1.11 Mg/m3.Newer threads,both extruded and cut,made from Neoprene(polychloroprene)rubber,generally have a specific gravity of between 1.20 and1.35.It is necessary,therefore,to have a