1、Designation:D4724/D4724M21Standard Test Method forEntanglements in Filament Yarns by Needle Insertion1This standard is issued under the fixed designation D4724/D4724M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last r
2、evision.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 two options for the measure-ment of entanglements in filament yarns using needle insertionoptions for ins
3、trument(Option 1)(Option 2)techniques.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system are not necessarily exact equivalents;therefore,toensure conformance with the standard,each system shall beused independently of
4、 the other,and values from the twosystems shall not be combined.1.3 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,health,and environmental practices and deter-mi
5、ne the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations
6、issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD2258 Practice for Sampling Yarn for TestingD4849 Terminology Related to Yarns and Fibers
7、3.Terminology3.1 Definitions:3.1.1 For definitions of terms relating to yarns and fibers,refer to Terminology D4849.3.1.1.1 The following terms are relevant to this standard:entanglement,filament yarn.3.2 For definitions of other textile terms used in this testmethod,refer to Terminology D123.4.Summ
8、ary of Test Method4.1 A summary of each option is in the section for thatoption.5.Significance and Use5.1 Option 1 of this test method is for the determination ofthe degree of filament yarn entanglement,as measured instru-mentally.It is used for acceptance testing of commercialshipments;however,caut
9、ion is advised because information onbetween-laboratory precision is lacking.Comparative tests,asdirected in 5.1.1,may be advisable.5.1.1 If there are differences of practical significance be-tween the reported test results for two or more laboratories,comparative tests should be performed by those
10、laboratories todetermine if there is a statistical bias between them,usingcompetent statistical assistance.As a minimum,samples usedfor each comparative test should be as homogeneous aspossible,drawn from the same lot of material as the samplesthat results in disparate results during initial testing
11、,andrandomly assigned in equal numbers to each laboratory.Otherfabrics with established test values may be used for thispurpose.The test results from the laboratories involved shouldbe compared statistically.If a bias is found,either its causemust be found and corrected or future test results must b
12、eadjusted in consideration of the known bias.5.2 Option 2 for this test method is intended for use whenthe supply of yarn is limited.5.3 The instrumental option of this test method,Option 1,isbased on the total randomization of the entanglements in theyarn;therefore,the distance measured between the
13、 point ofinsertion of a pin in the middle of the yarn and the point atwhich an entanglement is encountered,by movement of theyarn or the pin until it is stopped at a preset level of force,isrepresentative of the distance between two entanglements atsome location in the yarn.5.4 Entanglements are use
14、d frequently instead of twist toensure the integrity of filament yarns.Such entanglements1This 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 Jan.1,2021.Published January 2021.
15、Originallyapproved in 1999.Last previous edition approved in 2020 as D472420.DOI:10.1520/D4724_D4724M-21.2For 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 Do
16、cument Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.generally give somewhat less protection