ASTM_D_5866_-_12.pdf

Designation:D586612Standard Test Method forNeps in Cotton Fibers1This standard is issued under the fixed designation D5866;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 measurement of the quantityand size of neps in cotton using various instruments.1.2 This test method is intended for testing ginned cottonand cotton taken from various fiber processing stages.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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 TextilesD1441 Practice for Sampling Cotton Fibers for TestingE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodD7139 Terminology for Cotton Fibers3.Terminology3.1 For all terminology related to D13.11,refer to Termi-nology D7139.3.1.1 The following terms are relevant to this standard:ginned lint,nep,sliver.3.2 For all other terminology related to textiles,refer toTerminology D123.4.Summary of Test Method4.1 A pre-weighed mass of cotton fibers is prepared perinstrument manufacturer specifications.The instrument thenquantifies the neps and measures the size(diameter)of eachnep.4.2 Test data shows the mean or average nep size and thetotal number of neps per unit mass.5.Significance and Use5.1 Entangled cotton fibers that form neps have two sources:those that occur naturally as the cotton fiber develops on theplant into lint that is ready to be harvested and those that occurfrom mechanical action in harvesting,ginning,cleaning,card-ing or from a combination of mechanical action.5.2 This test method does not identify whether the nepscounted and measured are a result of seed variety,environmen-tal influences,type of harvesting,or a result of mechanicalprocessing.However,this information can be obtained fromstudies where samples are taken from plants in the field beforeharvesting and ginning,before and after cleaning,and cardingbefore spinning.5.3 The measurement of nep size and quantity going into,and coming out of,a fiber processing stage are commonly usedto make adjustments in the processing machinery to reduce oreliminate the generation of mechanical neps.Neps that remainin spun yarns have a direct influence on neps in fabrics.Foralmost all types of yarn or fabric,neps are considered defects.5.4 This test method provides a consistent and repeatablemeasurement of fiber nep count and size.Check cotton samplessupplied by the manufacturer are used to verify consistentmeasurement levels and laboratory-to-laboratory precision.5.5 This test method is considered satisfactory for accep-tance testing when the levels of the laboratories are controlledby the use of the same reference standard cotton samplesbecause the current estimates of between-laboratory precisionare acceptable under these conditions.If there are differencesof practical significance between reported test results for twolaboratories or more,comparative tests should be performed todetermine if there is a statistical bias between them usingcompetent statistical assistance.At a minimum,ensure the testsamples to be used are as homogeneous as possible,are drawnfrom the material from which the disparate test results wereobtained,and are randomly assigned in equal numbers to eachlaboratory for testing.The test from the two laboratories shouldbe compared using a statistical test for unpaired data,at aprobability level chosen prior to the testing series.If a bias is1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.11 on Cotton Fibers.Current edition approved Dec.1,2012.Published January 2013.Originallyapproved in 1995.Last previous edition approved in 2005 as D5866 05.DOI:10.1520/D5866-12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 found,either its cause must be found and corrected,or futuretest results for that material must be adjusted in considerationof the known bias.6.Apparatus and Material6.1 An instrument with a fiber individualizer for opening,cleaning,and individualizing the fibers,and with an appropri-ate sensor for counting and sizin