1、Designation: D 2645 07Standard Tolerances forYarns Spun on the Cotton or Worsted Systems1This standard is issued under the fixed designation D 2645; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These tolerances are applicable to all yarns spun on thecotton or the worsted system, either carded or combed, andcomposed of any fiber or
3、mixture of fibers, except cotton tirecords and novelty or fancy yarns.1.2 These tolerances are applicable only to yarns taken frompackages, and not to yarns taken from greige or processedfabrics.NOTE 1For tolerances for other spun yarns, see Tolerances D 2644,Methods D 179 and D 738, and Specificati
4、ons D 541 and D 681.1.3 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 and health practices and determine the applica-bility of regulatory limitations prior to
5、 use.2. Referenced Documents2.1 ASTM Standards:2D 123 Terminology Relating to TextilesD 179 Methods for Testing Tire Cords and Cord FabricsMade from Cotton3D 541 Specification for Single Jute Yarn3D 681 Specification for Jute Rove and Piled Yarn forElectrical and Packing Purposes3D 738 Methods for R
6、ope Made from Bast and Leaf Fibers3D 1422 Test Method for Twist in Single Spun Yarns by theUntwist-Retwist MethodD 1423 Test Method for Twist in Yarns by Direct-CountingD 1578 Test Method for Breaking Strength of Yarn in SkeinFormD 1907 Test Method for Linear Density of Yarn (YarnNumber) by the Skei
7、n MethodD 2255 Test Method for Grading Spun Yarns for Appear-anceD 2256 Test Method for Tensile Properties of Yarns by theSingle-Strand MethodD 2257 Test Method for Extractable Matter in TextilesD 2258 Practice for Sampling Yarn for TestingD 2494 Test Method for Commercial Mass of a Shipment ofYarn
8、or Manufactured Staple Fiber or TowD 2644 Tolerances for Yarns Spun on the Woolen SystemD 4849 Terminology Relating to Yarns and Fibers3. Terminology3.1 For all terminology relating to D13.58, Yarns andFibers, refer to Terminology D 4849.3.1.1 The following terms are relevant to this standard:cotton
9、 system, tolerances, worsted system.3.2 For all other terminology related to extiles, refer toTerminology D 123.4. Sampling4.1 Take samples as directed in the applicable materialspecification, or in the absence of specifications, proceed asdirected in Practice D 2258.5. Tolerances5.1 StrengthThe ave
10、rage breaking force of each lot shallbe equal to or greater than the specified minimum.5.2 Yarn Number:5.2.1 The average yarn number of yarns spun on cottonsystem or the worsted system shall conform to the limits:specified value6 4.0 % of the specified value.5.3 Twist:5.3.1 The direction of twist in
11、 each package or end shall beS or Z, as specified.5.3.2 In all cotton-system yarns except single yarns made ofcotton, the average twist shall conform to the limits: specifiedvalue 6 5.0 % of the specified value. In single cotton yarns,including the single yarn components of plied cotton yarns, theav
12、erage twist shall conform to the limits: specified value 610.0 % of the specified value. In yarns spun on the worstedsystem the average twist shall conform to the limits: specifiedvalue 6 7.5 % of the specified value.5.4 Extractable MatterThe average percent extractablematter in yarns spun on the wo
13、rsted system shall not exceed thefollowing values:%1These tolerances are under the jurisdiction of ASTM Committee D13 onTextiles and are the direct responsibility of Subcommittee D13.58 on Yarns andFibers.Current edition approved Jan. 1, 2007. Published January 2007. Originallyapproved in 1967. Last
14、 previous edition approved in 2001 as D 2645 95 (2001).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.3Withd
15、rawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Oil-spun yarns 4.0Dry-spun yarns 1.755.5 AppearanceAt least 80 % of the specimens examinedshall be equal in appearance to the standard for the specifiedgrade. The remaining 20 % sh
16、all not fall below the next lowergrade.5.6 Uniformity:5.6.1 Yarns Spun on the Cotton SystemThe coefficients ofvariation of individual observations shall not exceed the limitsin Table 1.5.6.2 Yarns Spun on the Worsted SystemThe average twistof the package containing the highest average twist shall no
17、t behigher than that of the package containing the lowest averagetwist by more than 15.0 % of the lower average.5.7 Commercial MassIn the absence of other contractualagreements, the invoice mass, that is the commercial mass asadopted in a specific branch of the textile trade, and asdetermined by the
18、 supplier, shall not exceed the commercialmass as determined by the purchaser, by more than 1 %. Inbranches of the textile trade which use the net mass as thecommercial mass, the latter is subject to the same limitation.NOTE 2Particular attention is drawn to the results of an interlabora-tory test d
19、escribed in Section 10 of Method D 2494.6. Test Methods6.1 StrengthDetermine the breaking force as directed inTest Method D 1578, or Test Method D 2256, as agreed orspecified.6.2 Yarn NumberDetermine the yarn number by TestMethod D 1907, using Option 1 for cotton system yarns andOption 1, 3, or 6 fo
20、r worsted-spun yarns, as agreed or specified.6.3 TwistDetermine the twist as directed in Test MethodD 1423, or, by agreement (for single yarns only), Test MethodD 1422.6.4 Extractable MatterDetermine the percent extractablematter as directed in Test Method D 2257.6.5 Yarn AppearanceDetermine the app
21、earance grade ofyarns as directed in Test Method D 2255.6.6 MassDetermine the net mass and, if required, thecommercial mass of the shipment as directed in Test MethodD 2494.7. Conformance7.1 The purchaser and supplier may agree on a procedure toestablish conformance, including control charts furnish
22、ed bythe supplier, a sequential-sampling plan, or the double-sampling plan outlined in 7.2.7.2 In the absence of a control-chart or sequential-samplingplan, proceed as directed in 7.2.1-7.2.3.7.2.1 If the test results for the lot conform to the tolerancesfor all characteristics specified in Section
23、5, consider the lot avalid delivery.7.2.2 If the test results for one or more characteristics do notconform to the tolerances, take a new laboratory sample fromeither the original lot sample or a new lot sample. Retest the lotfor the characteristic(s) that did not conform to the tolerancesin the fir
24、st test, and average the results of the first and secondsamples as if the results were from one test of double theoriginal number of specimens. If the new average(s) con-form(s) to the specified tolerances, consider the lot a validdelivery.7.2.3 If the test results obtained as directed in 7.2.2 do n
25、otconform to the specified tolerances, consider the lot a nonvaliddelivery.8. Keywords8.1 appearance; commercial mass; cotton system; extract-able matter; strand; tolerance; twist; strength; unevenness;worsted system; yarn; yarn-numberASTM International takes no position respecting the validity of a
26、ny patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to re
27、vision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. You
28、r comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copy
29、righted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.or
30、g (e-mail); or through the ASTM website(www.astm.org).TABLE 1 Coefficients of Variation of Individual ObservationsACarded,%Combed,%Yarn number 5 4Breaking force, skein 8 6Breaking force, single strand 18 16Twist (direct-counting method) 25 22Twist (untwist-twist, 12.5 cm (5 in.) 14 12Twist (untwist-twist, 25.0 cm (10 in.) 12 10AHigher coefficients of variation than those listed may indicate either poorcontrol of the manufacturing processes or mixed yarn from two or more productionlots.D2645072
