1、Designation:D2255/D2255M09(Reapproved 2013)1Standard Test Method forGrading Spun Yarns for Appearance1This standard is issued under the fixed designation D2255/D2255M;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.1NOTEReferences to the adjuncts in 7.1 and 7.2 were updated editorially in December 2015.INTRODUCTIONCotton yarn appearance standards were f
3、irst adopted in 1938 and revised in 1964,with Series IIIbeing revised again in 1975.The 1964 boards had different yarn sizes for the four-grade exhibits oneach board.The 1975 Series III board used the same yarn number for each grade.The appearance grade of yarn is based on the composite evaluation o
4、f several factors,such asunevenness,fuzziness,and neppiness.The differences in the yarn numbers in the 1964 standards alongwith the differences in other factors distort the comparison between grades and makes grading moredifficult.To overcome this shortcoming,in 1975 the Series III board was revised
5、 using the same size yarnfor all four grades.After evaluating the improvements,it was decided to revise all of the series usinga mid-range yarn number for each grade in the series,and narrow the range in the most active series.This was accomplished by adding a new board,Series VI.Anear mid-range yar
6、n number was selectedto represent equal steps between adjacent grades for all the factors considered in yarn appearancegrading.These yarns were produced with current commercial manufacturing equipment and practices.Finally,to obtain better yarn definition and better reproducibility from set to set,i
7、t was decided touse offset photo printing.Shortly after these new boards were published in 1979,it became apparent that in the Series II-79Board the A and B grades were not clearly defined and appeared to be switched.This was correctedin the 1987 Series II Board.In 1987 a world wide survey was condu
8、cted on how the Yarn Appearance Boards were being used.From responses it became apparent that the boards are being used for grading yarns other than 100%cotton combed or carded yarns.Respondents were using the boards to grade yarn blends,ring spunyarns,open-end spun yarns and other spinning systems.
9、The boards are used both for process qualitycontrol and customer acceptance.In view of the above findings,it was decided to revise the method to include grading of all singlespun yarns.1.Scope1.1 This test method covers the grading of singles spunyarns for appearance.1.2 This test method does not ap
10、ply to plied yarns.1.3 The values stated in either inch-pound or SI units are tobe regarded separately as the standard.The values stated ineach system are not exact equivalents,therefore,each systemmust be used independently of the other.Combining valuesfrom the two systems may result in non-conform
11、ance with thestandard.1.4 This standard does not purport to address the safetyconcerns associated with its use.It is the responsibility of theuser of this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.21This test
12、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 September 2013.Originallyapproved in 1964.Last previous edition approved in 2009 as D2255 09.DOI:10.1520/D2255_D
13、2255M-09R13E01.2The requirements for the appearance of cotton yarns are covered in TolerancesD2645,Roller-Drafted Yarns.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.Referenced Documents2.1 ASTM Standards:3D123 Terminology Relating to
14、 TextilesD2258 Practice for Sampling Yarn for TestingD2645 Tolerances for Yarns Spun on the Cotton or WorstedSystemsD3888 Terminology for Yarn Spinning SystemsD3990 Terminology Relating to Fabric DefectsD4849 Terminology Related to Yarns and Fibers2.2 ASTM Adjuncts:4Spun Yarn Appearance Standards(6
15、Boards with Photos)3.Terminology3.1 For definitions of textile terms used in this method:bunch,cover,fuzz,nep,slub,thick place,thin place,and yarnappearance,refer to Terminology D4849.For other textileterms used in this test method,refer to Terminology D123,Terminology D3888,and Terminology D3990.4.
16、Description of Yarn Grades4.1 Grade A YarnGrade A yarn may have no large nepswhich are over three times the normal diameter of the yarn andvery few small ones.Grade A yarn must have good uniformityfrom 25 mm to 25 mm(inch to inch),and good cover withoutexcessive fuzziness.No foreign matter may be present inGrade A yarn.4.2 Grade B YarnGrade B Yarn may have no large neps,but may have a few small ones.Grade B yarn may have nomore than three small pieces of foreign matter per board orspecimen provi