ASTM_D_3883_-_04_2012.pdf

Designation:D388304(Reapproved 2012)Standard Test Method forYarn Crimp and Yarn Take-up in Woven Fabrics1This standard is issued under the fixed designation D3883;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 determination of the rela-tionship between the length of a piece of fabric and the lengthof the yarn in the fabric by measurement of the yarn crimp andyarn take-up.1.2 This test method applies to woven fabrics.1.3 The values stated in either SI or inch-pound units are tobe regarded separately as standard.Within the text,theinch-pound units are shown in parentheses.The values statedin each system are not exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in nonconformancewith the specification.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 TextilesD2904 Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed Data(With-drawn 2008)3D2906 Practice for Statements on Precision and Bias forTextiles(Withdrawn 2008)3D4849 Terminology Related to Yarns and FibersD4850 Terminology Relating to Fabrics and Fabric TestMethods3.Terminology3.1 For definition of textile terms used in this test method:bench marks,refer to Terminology D4849.3.2 For definitions of textile terms used in this test method:yarn crimp and yarn take-up,refer to Terminology D4850.3.3 For definitions of other textile terms used in this testmethod,refer to Terminology D123.4.Summary of Test Method4.1 Bench marks are placed on a length of a yarn as it liesin a woven fabric.The distance between the bench marks ismeasured.The yarn is removed from the fabric,straightened byapplying suitable tension,and the distance between the benchmarks is remeasured.Yarn crimp is the change in lengthexpressed as a percent and based on the in-fabric distance.Yarntake-up is the change in length expressed as a percent andbased on the out-of-fabric distance.5.Significance and Use5.1 The relationship of the length of a piece of fabric and thelength of yarn in the fabric can be determined accurately onlybe measuring the length of yarn entering the loom and thelength of fabric made from that particular length of yarn.Inmost cases,however,the determination must of necessity bemade on a woven fabric by measuring the length of yarnremoved from a measured length of fabric,thus introducingcertain variations that will influence the accuracy of the test.Yarn removed from the woven fabric contains undulations orwaves that have been introduced by the weaving process.Heat,moisture,and mechanical shrinkage on subsequent finishingoperations may accentuate these undulations,and in allprobability,increase the force to pull them out and straightenthe yarn.In order to accurately measure the length of the yarnafter the removal of the crimp,these undulations must bepulled out without elongating the yarn.In some cases,theminimum force necessary to straighten the yarn will cause acertain amount of the elongation to take place,thus increasingthe length of the yarn.Also,stresses imposed upon the yarnduring the weaving process may have been sufficient to stretchthe yarn beyond its elastic limit,again increasing its length.Itis recognized that determination made by measuring length ofyarn removed from a measured length of fabric may tend togive crimp values that are somewhat higher than the crimp in1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.59 on Fabric Test Methods,General.Current edition approved July 1,2012.Published August 2012.Originallyapproved in 1980.Last previous edition approved in 2008 as D3883 04(2008).DOI:10.1520/D3883-04R12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 the yarn as it lay in the fabric.In the case of fabrics made fromyarns that exhibit differential shrinkage,or yarns of widelydifferent count,or yarns woven at different tensions,the crimpof each type of yarn in th