ASTM_D_3412_-_D_3412M_-_13.pdf

Designation:D3412/D3412M13Standard Test Method forCoefficient of Friction,Yarn to Yarn1This standard is issued under the fixed designation D3412/D3412M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the measurement of frictionalproperties for both continuous filament and spun-staple yarnsunder boundary friction conditions.1.2 This test method has been used with yarns having lineardensities ranging from 1.5 to 400 tex,but may be used withyarns outside these ranges 15 to 3600 denier.NOTE1For coefficient of friction,yarn to metal,see Test MethodD3108/D3108M.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 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:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD1907 Test Method for Linear Density of Yarn(Yarn Num-ber)by the Skein MethodD2258 Practice for Sampling Yarn for TestingD3108/D3108M Test Method for Coefficient of Friction,Yarn to Solid MaterialD4849 Terminology Related to Yarns and Fibers3.Terminology3.1 For all terminology relating to D13.58,Yarns andFibers,refer to Terminology D4849.3.2 For all other terminology related to textiles,refer toTerminology D123.4.Summary of Test Method4.1 A length of yarn is moved at a known speed in contactwith itself or similar yarn at a specified wrap angle.The inputand output tensions are measured and the coefficient of frictioncalculated.Alternatively,apparatus may be used in which theratio of input to output tension is measured allowing thecoefficient of friction to be indicated directly.4.2 Three optional procedures are included.Option 1 isbased on the Twisted Strand Method,using a wrap angle of15.71 rad 900.Option 2 is based on the Capstan Method,using a wrap angle of 3.14 radians 180.Option 3 is based onthe Fixed Yarn-Body Capstan Method,using a wrap angle of3.14 radians 180.NOTE2Editions of Test Method D3412/D3412M prior to the 1986revision incorrectly stated the wrap angle for Option 1 to be 18.85 rad.This is incorrect,since 3 turns of the swivel pulley do not result in a wrapangle of 18.85 radians.This has now been corrected to 15.71 rad.Thisshould be taken into account in comparing with earlier results.5.Significance and Use5.1 This test method for testing yarn-to-yarn friction isbeing used,but is not recommended,for acceptance testing ofcommercial shipments since between-laboratory precision isknown to be poor.5.1.1 In some cases,the purchaser and supplier may have totest a commercial shipment of one or more specific materialsby the best available method even though the method has notbeen recommended for acceptance testing of commercialshipments.In case of a dispute arising from differences inreported test results when using Test Method D3412/D3412Mfor acceptance testing of commercial shipments,the purchaserand the supplier should conduct comparative tests to determineif there is a statistical bias between their laboratories.Compe-tent statistical assistance is recommended for the investigationof bias.As a minimum,the two parties should take a group oftest specimens that are as homogeneous as possible and that arefrom a lot of material 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 forunpaired data and an acceptable probability level chosen by the1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Current edition approved July 1,2013.Published August 2013.Originallyapproved in 1975T.Last previous edition approved in 2007 as D3412 07.DOI:10.1520/D3412_D3412M-13.2For 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 two parties before the testing is begun.If a bias is found,eitherits cause must be found and corrected or the purchaser and t