1、Designation: D1907/D1907M 12 (Reapproved 2018)Standard Test Method forLinear Density of Yarn (Yarn Number) by the Skein Method1This standard is issued under the fixed designation D1907/D1907M; the number immediately following the designation indicates theyear of original adoption or, in the case of
2、revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This test
3、method covers the determination of the lineardensity of all types of yarn in package form, subject to thelimitations of size and stretch given in 1.2 and 1.3. Provision ismade for expressing yarn linear density in all the traditionalyarn numbering systems.1.2 This test method is applicable to yarns
4、that stretch lessthan 5 % when tension on the yarn is increased from 0.25 to0.75 cN/tex 0.25 to 0.75 gf/tex. By mutual agreement, anduse of a lower than specified reeling tension, this method mayalso be adapted to measure the linear density of yarns thatstretch more than 5 %, under the above force.1
5、.3 This method is applicable to yarns finer than 2000 tex.However, it may be also adapted to coarser yarns by the use ofskeins of shorter than specified lengths, and alternate reelingconditions, agreeable to the interested parties.1.4 Depending on the procedure used to calculate themoisture content
6、of the yarn being tested, and its actualmoisture content, or finish content, or both, one or more of thefollowing options may be utilized.1.4.1 Unscoured Yarn: Option 1Yarn at equilibrium withthe standard atmosphere for testing textiles.Option 2Oven-dried yarn.Option 3Oven-dried yarn, plus commercia
7、l moisture re-gain.1.4.2 Scoured Yarn: Option 4Scoured yarn at equilibriumwith the standard atmosphere for testing textiles.Option 5Oven-dried, scoured yarn.Option 6Oven-dried, scoured yarn, plus commercial mois-ture regain.Option 7Oven-dried, scoured yarn, plus commercial al-lowance (commercial moi
8、sture regain, plus an allowance forfinish).1.5 Specimens used to determine yarn linear density mayalso be used to determine the skein breaking strength of theyarn. Hence, this method provides the sequence of steps to befollowed, to determine both these yarn properties.NOTE 1The linear density of yar
9、ns produced with jute, or glass, mayalso be determined by the following approved methods: SpecificationsD541, D578/D578M, and D681. The linear density of short yarnsegments, raveled from fabrics, may be determined by Test MethodD1059.1.6 The values stated in either SI units or inch-pound unitsare to
10、 be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.7 This standard does not purport to address all of
11、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-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in acc
12、or-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 AS
13、TM Standards:2D123 Terminology Relating to TextilesD541 Specification for Single Jute Yarn (Withdrawn 1996)3D578/D578M Specification for Glass Fiber StrandsD681 Specification for Jute Rove and Plied Yarn for Elec-trical and Packing Purposes (Withdrawn 2000)3D1059 Test Method for Yarn Number Based on
14、 Short-Length SpecimensD1578 Test Method for Breaking Strength of Yarn in SkeinForm1This 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 July 1, 2018. Published July 2018. Origi
15、nally approvedin 1961 T. Last previous edition approved in 2012 as D1907/D1907M 12. DOI:10.1520/D1907_D1907M-12R18.2For 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 t
16、he standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in acco
17、rdance 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.1D1909 Standard Tables of Commer
18、cial Moisture Regainsand Commercial Allowances for Textile FibersD2257 Test Method for Extractable Matter in TextilesD2258/D2258M Practice for Sampling Yarn for TestingD2494 Test Method for Commercial Mass of a Shipment ofYarn or Manufactured Staple Fiber or TowD4849 Terminology Related to Yarns and
19、 Fibers3. Terminology3.1 For all terminology relating to D13.58, Yarns andFibers, refer to Terminology D4849.3.1.1 The following terms are relevant to this standard:commercial allowance, commercial moisture regain, directyarn numbering system, indirect yarn numbering system, lineardensity for fiber
20、and yarn, skein, yarn number, yarn numberingsystem.3.2 For all other terminology, refer to Terminology D123.4. Summary of Test Method4.1 Specified lengths of yarn are wound on reels as skeins,and weighed. The linear density of the yarn is computed fromthe mass and length of the skein. In some option
21、s, the skein isscoured before weighing, and, depending on the option chosen,the mass of the skein may be determined after oven drying, orafter conditioning.5. Significance and Use5.1 Test Method D1907/D1907M is considered satisfactoryfor acceptance testing of commercial shipments, since it hasbeen u
22、sed extensively in the trade for that purpose.5.1.1 In case of dispute arising from differences in reportedtest results when using Test Method D1907/D1907M foracceptance testing of commercial shipments, the purchaser andthe supplier should conduct comparative tests to determine ifthere is a statisti
23、cal bias between their laboratories.5.1.2 Competent statistical assistance is recommended forthe determination of such a bias.As a minimum, the two partiesshould take a group of test specimens that are as homogeneousas possible, and that are from the same lot of the material inquestion. The test spe
24、cimens should then be randomly assignedin equal numbers to each laboratory for testing. The averageresults from the two laboratories should be compared usingstatistical analysis for unpaired data, and an acceptable prob-ability level chosen by the parties before testing begins. If abias is found, ei
25、ther its cause must be identified and corrected,or the purchaser and supplier must agree to interpret future testresults for that material with consideration to the known bias.5.2 This test method is intended primarily for the determi-nation of the average linear density of yarns. However, thevariat
26、ions identified by the results may also provide usefulinformation. If the coefficient of variation is to be calculated,each skein must be weighed separately, and a larger number ofskeins will need to be tested (as compared to the number ofskeins to be tested for the determination of the average yarn
27、linear density alone).5.3 This test method includes seven options, depending onwhether the yarn is scoured before weighing, weighed in theconditioned or oven-dried state, or whether or not the resultsobtained are adjusted for commercial moisture regain, or acommercial allowance. Option 1 (unscoured,
28、 conditioned yarn)is generally used for yarns spun on the cotton system, whileOptions 6 and 7 (scoured, oven dried yarn, plus commercialmoisture regain, or allowance) are generally used for filamentyarns, or yarns containing wool fibers. The specific options tobe used in any instance shall be agreed
29、 upon by the parties, oras prescribed in test methods or tolerances.5.4 In Options 2, 3, 5, 6, and 7, an oven-dried sample isobtained by exposing the yarn in an oven with a supply of airat standard textile testing conditions, as described in 6.3.6. Apparatus and Reagents6.1 Reel:6.1.1 GeneralA hand
30、reel or motor driven reel having aperimeter of 1.000 m or 1.500 yd. with a tolerance of 60.25 %is recommended. By prior agreement, reels having a perimeterof between 1.0 and 2.5 m 1.5 and 3.0 yd may be used. Thereel shall be fitted with a traversing mechanism that will avoidbunching successive wraps
31、 of yarn, and with an indicator of thelength wound.Awarning bell that rings at a specified length, isalso recommended.And, it is advisable that one arm of the reelbe collapsible, to allow for easy removal of the wound skeins.6.1.2 Reel PerimeterDetermine the actual perimeter of thereel by winding a
32、0.6 cm. 0.25 in. wide steel measuring tapearound the reel. Tension the tape prior to directly reading thecircumference of the reel, by attaching a 0.5 kg 1.0 lb weightto the end of the tape. Repeat this measurement near each endof the bars of the reel, and in the center. If the circumferenceat any o
33、f these areas is outside the limits of 1.000 6 2.5 mm1.500 + 0.1 in., adjust the fly wheel to bring the measure-ment(s) within the limits.6.1.3 Yarn TensioningThe reel shall be fitted with either apositive feed system at a controlled tension of 0.5 cN/tex0.05 gf tex or with an adjustable tension dev
34、ice. The lengthof the skeins should be checked, and variations in length not beallowed to exceed 60.25 % (see Annex A1).6.2 BalanceFor the determination of average yarn lineardensity, a balance of suitable capacity, graduated in grams orgrains, with a sensitivity of 1 part in 1000 should be used. If
35、single skeins are weighed, a balance graduated directly in yarnlinear density may be used.NOTE 2The 1:1000 balance sensitivity is needed to ascertain thecompletion of conditioning, or oven drying. For subsequent weighings ofskeins, a 1:500 sensitivity has been found to be sufficient.NOTE 3For the ca
36、lculation of the variation of yarn linear density, a1:100 balance sensitivity is sufficient to weigh individual skeins, after theskeins are conditioned, or oven-dried.6.3 Drying OvenAn oven, ventilated and capable of beingcontrolled in a temperature range of 105 6 3C 221 6 5F,is required to dry the
37、skeins. The oven should be of sufficientdesign to facilitate the free passage of air through thespecimens, and should be supplied with a current of airsufficient to change the air in the oven once every 4 min. Thespecimens shall be protected from any direct heat, radiatingfrom the heating units of t
38、he oven. Air supplied to the ovenshall be at the standard atmosphere for testing textiles. TheD1907/D1907M 12 (2018)2oven may be provided with facilities to shut off the air currentand weigh the specimens, without removing them from theoven.6.4 Facilities for Scouring (Options 4, 5, 6, and 7), asind
39、icated in Appendix X2, or in Sections 6.1 and 6.3 of TestMethod D2494.6.5 Weighing Cans, with tight fitting lids, and of sufficientsize to hold all skeins, or groups of skeins (Options 2, 3, 5, 6,and 7), if the weighing is to be done outside the oven.Weighingbottles with ground-glass stoppers may al
40、so be used.6.6 Auxiliary Facilities, suited to the specimens and optionsused, such as sample supports, tared wire gauze baskets ofcorrosion resistant metal, dessicators of sufficient size to holdthe weighing cans or bottles, and an efficient dessicant.7. Sampling7.1 Lot SampleAs a lot sample for acc
41、eptance testing, takeat random the number of shipping units directed in anapplicable material specification, or other agreement betweenthe purchaser and supplier, such as an agreement to usePractice D2258/D2258M. Consider cartons or other shippingunits to be the primary sampling units.NOTE 4An adequ
42、ate specification or other agreement between thepurchaser and the supplier requires taking into account the variabilitybetween shipping units, between packages or ends within a shipping unit,and between specimens from a single package, to provide a sampling planwith a meaningful producers risk, user
43、s risk, acceptable quality level,and limiting quality level.7.2 Laboratory SampleAs a laboratory sample for accep-tance testing, take at random from each shipping unit in the lotsample the number of packages or ends directed in anapplicable material specification, or as agreed to betweenpurchaser an
44、d supplier (such as an agreement to use PracticeD2258/D2258M). Preferably, the same number of packagesshould be taken from each shipping unit in the lot sample.7.2.1 Average of Yarn Linear DensityWhen only theaverage of the yarn linear density is to be determined, take alaboratory sample as follows:
45、Filament yarns 5 packagesYarns spun on Worstedor Cotton systems 10 packagesYarns spun on Bast, orWoollen systems 20 packages7.2.2 Average and Variability of Yarn Linear DensityWhen both the average and variability of the linear density ofyarn are to be determined, take a laboratory sample of 30packa
46、ges. If possible, take an equal number of randomlyselected packages from each case in the lot sample.7.3 Test SpecimensTest one skein from each package inthe laboratory sample.NOTE 5Since the variation in yarn linear density is usually higherbetween packages than within packages, no appreciable impr
47、ovement inprecision can be expected by testing more than one skein from eachpackage.7.3.1 An exception to the information provided in Note 5may occur in packages of filament yarns; consistent differencesin yarn linear density are sometimes present between yarn onthe outside of the package, as compar
48、ed to yarn on the inside.If such differences are suspected, test more than one skein fromeach package, without reducing the number of packagessampled for testing, taking skeins at intervals throughout thepackages.8. Conditioning8.1 Before reeling test skeins, condition yarn in skein formin the stand
49、ard atmosphere for testing textiles for a minimumof 1 h, and yarn on packages for a minimum of 3 h.Additionally, prior to testing, preconditioning of the test skeinsmay be required for Option 1, but is not necessary for Options2 through 7.NOTE 6For Options 2 through 7, where the yarn is scoured oroven-dried after reeling, conditioning prior to reeling is required to ensurea correct skein length.9. Procedure9.1 General:9.1.1 The procedure used depends on the options selected;Table 1 shows the steps to be followed for each option.9.1.2 I
