ASTM_D_76_-_D_76M_-_11.pdf

Designation:D76/D76M11Standard Specification forTensile Testing Machines for Textiles1This standard is issued under the fixed designation D76/D76M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers the operating characteristics ofthree types of tensile testing machines used for the determina-tion of the force-elongation properties of textile materials.These types of tensile testing machines are:1.1.1 Constant-rate-of-extension,CRE.1.1.2 Constant-rate-of-traverse,CRT.1.1.3 Constant-rate-of-loading(force),CRL.1.2 Specifications for tensile testing machines to measureother tensile-related properties of textile materials not coveredby this standard are given in the ASTM standards using thosemachines.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 The following safety hazards caveat pertains only to thetest methods described in this specification:This standard doesnot 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 practicesand determine the applicability of regulatory limitations priorto use.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD2256 Test Method for Tensile Properties of Yarns by theSingle-Strand MethodD4849 Terminology Related to Yarns and FibersE4 Practices for Force Verification of Testing MachinesE74 Practice of Calibration of Force-Measuring Instrumentsfor Verifying the Force Indication of Testing Machines3.Terminology3.1 For terminology related to tensile testing,see Terminol-ogy D4849.3.1.1 The following terms are relevant for this standard:bench marks,calibrate,capacity,clamp,constant-rate-of ex-tension type tensile testing machine(CRE),constant-rate-of-load tensile testing machine(CRL),constant-rate-of-traversetensile testing machine(CRT),effective carriage mass,effec-tive gauge length,grip,jaw face,jaw liner,jaws,least count,nominal gauge length,response time,sensitivity,in electronicsystems,sensitivity,stress,tensile testing machine,test skein,time-to-break,true gauge length.3.1.2 For all other terminology related to textiles,seeTerminology D123.4.Performance Requirements4.1 Individual ASTM methods for tensile testing of textilematerials that prescribe apparatus which conforms to thisspecification shall also include such other detailed specifica-tions as may be necessary to describe the testing machine andits operation completely.4.1.1 This specification shall not be construed as beingintended to preclude the evolution of improved methods oftesting or testing apparatus,which is recognized as being vitalin an advancing technology.4.2 Comparison of results from tensile testing machinesoperating on different principles is not recommended.Whenthese machines are used for comparison testing however,constant time-to-break at 20 6 3 s is the established way ofproducing data,but even then the data may differ significantly.4.2.1 Comparison of test data from machines of the sametype,especially two or more CRT-type or two or moreCRL-type machines,requires consideration of the effect ofindividual machine characteristics;for example,inertia effects,capacity,sensitivity,type of loadcell,etc.,which may causesignificant differences in results even though uniform proce-dures are employed.Data from different CRE-type testingmachines,however,should not be significantly different.4.2.2 In any case,all types of tensile testing machines mustsatisfy the accuracy requirements as given in Section 7.1This specification is under the jurisdiction of ASTM Committee D13 onTextiles and is the direct responsibility of Subcommittee D13.58 on Yarns andFibers.Current edition approved Dec.1,2011.Published December 2011.Originallyapproved in 1920.Last previous edition approved in 2005 as D76 99(2005).DOI:10.1520/D0076_D0076M-11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandardsvolume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.3 While changes in humidity affect the tensile propertiesof many textile materials,changes in humidity normally do notaffect the testing machines themselves.4.4 When machines are moved to different locations,theircalibration shall be verified to make sure that they still meet t