1、Designation:D764212Standard Practice forEstablishment of Calibration Cottons for CottonClassification Instruments1This standard is issued under the fixed designation D7642;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of l
2、ast 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 practice provides instructions for the developmentof calibration cotton standards by establishing cotton fibervalues fo
3、r micronaire,length,uniformity index,and strength.The purpose of calibration cotton standards is for calibration ofcotton classification instruments to the level of the internation-ally recognized United States Department of Agriculture(USDA)Benchmark Reference Cotton Standards.The USDAhas establish
4、ed calibration cotton standards for domestic up-land and Extra Long Staple(ELS)cottons and this practiceprovides an instruction for other geographical regions toestablish their own calibration cotton standards for cottonclassification instruments.1.2 This practice shall be used for the establishment
5、 ofcalibration cottons for the testing of Upland and ELS cottons.1.3 Only saw ginned cottons shall be used in this practice.Roller gin cottons are not valid for use due to higher measure-ment variability.1.4 The calibration cotton established by this practice is notvalid for use as a micronaire cali
6、bration standard.The mi-cronaire standard value is not for the instrument calibration ofthe micronaire module;it is utilized by the instrument for thecorrection of the strength measurement during the calibrationroutine.1.5 The values stated in inch-pound are to be regarded as thestandard.The values
7、given in parentheses are mathematicalconversions to SI units that are provided for information only.1.6 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
8、practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD7139 Terminology for Cotton FibersD7410 Practice for Qualification of Cotton ClassificationInstruments for Cotton Marketing3.Terminology3.
9、1 For all the terminology related to D13.11,refer toTerminology D7139.3.1.1 The following terms are relevant to this standard:calibration cotton standards,candidate bale,Extra Long StapleCotton,fanhead,fanheading,length,ringer cotton,rollerginned cotton,saw ginned cotton,strength,Universal mi-cronai
10、re calibration cotton standards,USDA benchmark refer-ence cotton standard,value setting,value setting group,valuesetting subgroup.3.2 For definitions of all other textile terms see TerminologyD123.4.Summary of Practice4.1 In order to establish calibration cotton standards for usein calibration of co
11、tton classification instruments,testing shallbe performed on samples from each candidate bale while beingtested in conjunction with benchmark cottons and ringercottons.The samples shall be tested in a minimum of fourlaboratories and on a minimum of six cotton classificationinstruments.Established va
12、lues are calculated based on thelevel of the benchmark cottons.5.Significance and Use5.1 The purpose of this practice is to provide standardiza-tion in the value setting of calibration cotton standards to beused for cotton classification instrument calibration.1This test method is under the jurisdic
13、tion ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.11 on Cotton Fibers.Current edition approved July 1,2012.Published September 2012.DOI:10.1520/D7642122For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at service
14、astm.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 5.2 The practice provides procedures for the value settingfor cal
15、ibration cotton standards.These procedures are for useby cotton fiber testing organizations that establish standardvalues on candidate bales that will be utilized as calibrationcotton standards for cotton classification instruments on thelevel of the benchmark cottons.NOTE1Benchmark cottons are of h
16、igh value and of limited supply.Long term accuracy and stability of the internationally recognized USDAcotton standards are dependent on long term maintenance of the bench-mark cottons.Therefore,distribution of the benchmark cottons will betightly controlled by the USDA.6.Apparatus and Materials6.1 Cotton classification instruments with a fully automatedcomb sampling device.6.1.1 A minimum of six(6)total cotton classificationinstruments from a minimum of four(4)total laboratories shallbe utilize
