ASTM_D_5170_-_98_2015.pdf

Designation:D517098(Reapproved 2015)Standard Test Method forPeel Strength(“T”Method)of Hook and Loop TouchFasteners1This standard is issued under the fixed designation D5170;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 test method covers the measurement of the peelstrength of hook and loop touch fasteners using a recordingconstant-rate-of-extension tensile testing machine(CRE).1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety problems,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:2D618 Practice for Conditioning Plastics for Testing3.Significance and Use3.1 This test method gives a measure of a key property ofhook and loop touch fasteners which is of interest to users ofsuch devices.This is a means of determining the resistance toseparation when forces are applied normal to the line ofseparation of the fastener.3.2 The force registered in a peel test is irregular,and as aconsequence,empirical methods have had to be developed toobtain usable values related to peel strength.In spite of theempirical nature of the reported values,it is believed theyreflect comparative performance of similar touch fastenerstested and measured in the same way.3.3 Two optional methods of calculation are provided:integrator average and average of five highest peaks.These testmethods are not equivalent.Generally,the integrator averagewill be lower than the average of the five highest peaks.3.4 The highest peaks which reflect the force required toseparate a hook and loop closure bear no simple relationship tothe average force(integrator average).The average of the fivehighest peaks better reflect performance but the integratorresults may be used to characterize a closure and for qualitycontrol purposes.The integrator average is relatively easy tocalculate given the proper equipment.3.5 In the case of a dispute arising from differences inreported test results when using this test method for acceptancetesting of commercial shipments,the purchaser and the sup-plier should conduct comparative tests to determine if there isa statistical bias between their laboratories.Competent statis-tical assistance is recommended for the investigation of bias.As a minimum,the two parties should take a group of testspecimens which are as homogenous as possible and which arefrom a lot of hook and loop of the type in question.The testspecimens should then be randomly assigned in equal numbersto each laboratory for testing.The average results from the twolaboratories should be compared using Students t-test and anacceptable probability level chosen by the two parties beforethe testing began.If a bias is found,either its cause must befound and corrected or the purchaser and the supplier mustagree to interpret future test results in the light of the knownbias.4.Apparatus4.1 Rollerconsisting of a smooth steel surface,approxi-mately 434in.(121 mm)in diameter,214in.(57 mm)wide,and equipped with a handle,length 418in.(105 mm),forpropelling the roller back and forth without adding additionalweight to the specimen being rolled(See Fig.1).The weight ofthe roller(including the handle)is 11 614lbs.(4994 g 6 114g).4.2 Testing MachineA constant rate of extension(CRE)tensile tester shall be used.The tester shall have two clampswith centers in the same plane,parallel to the direction of themotion of the stressing clamp,and so aligned that they willhold the specimen ends wholly in the same plane;a means ofmoving the stressing clamp at a uniform rate of 12.0 6 0.51This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.54 on Subassemblies.Current edition approved Feb.1,2015.Published April 2015.Originallyapproved in 1991.Last previous edition approved in 2010 as D5170-98(2010).DOI:10.1520/D5170-98R15.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 in./min(305 6 13 mm/min),an autographic device for record-ing the load;and provided with an integrator if the integratoraverage is to be used.4.2.1 The instrument shall be calibrated to