1、Designation:D190707 Designation: D1907/D1907M 12Standard 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 o
2、f 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 Department of Defense.1. Scope1.1 This test met
3、hod covers the determination of the linear density of all types of yarn in package form, subject to the limitationsof size and stretch given in 1.2 and 1.3. Provision is made for expressing yarn linear density in all the traditional yarn numberingsystems.1.2 This test method is applicable to yarns t
4、hat stretch less than 5 % when tension on the yarn is increased from 0.25 to 0.75cN/tex (0.250.25 to 0.75 gf/tex).gf/tex. By mutual agreement, and use of a lower than specified reeling tension, this method mayalso be adapted to measure the linear density of yarns that stretch more than 5 %, under th
5、e above force.1.3 This method is applicable to yarns finer than 2000 tex. However, it may be also adapted to coarser yarns by the use of skeinsof shorter than specified lengths, and alternate reeling conditions, agreeable to the interested parties.1.4 Depending on the procedure used to calculate the
6、 moisture content of the yarn being tested, and its actual moisture content,or finish content, or both, one or more of the following options may be utilized.1.4.1 Unscoured Yarn:Option 1Yarn at equilibrium with the standard atmosphere for testing textiles.Option 2Oven-dried yarn.Option 3Oven-dried y
7、arn, plus commercial moisture regain.1.4.2 Scoured Yarn:Option 4Scoured yarn at equilibrium with the standard atmosphere for testing textiles.Option 5Oven-dried, scoured yarn.Option 6Oven-dried, scoured yarn, plus commercial moisture regain.Option 7Oven-dried, scoured yarn, plus commercial allowance
8、 (commercial moisture regain, plus an allowance for finish).1.5 Specimens used to determine yarn linear density may also be used to determine the skein breaking strength of the yarn.Hence, this method provides the sequence of steps to be followed, to determine both these yarn properties.NOTE 1The li
9、near density of yarns produced with jute, or glass, may also be determined by the following approved methods: Specifications D541,D578, and D681. The linear density of short yarn segments, raveled from fabrics, may be determined by Test Method D1059.1.6The values stated in SI units are to be regarde
10、d as standard. The values shown in parentheses are approximate conversionsto U.S. customary unit equivalents.1.6 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system sh
11、all be used independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish ap
12、propriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD541 Specification for Single Jute YarnD578 Specification for Glass Fiber Strands1This test method is under the
13、jurisdiction of ASTM Committee D13 on Textiles and is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Current edition approved Jan.July 1, 2007.2012. Published February 2007.August 2012. Originally approved in 1961 T. Last previous edition approved in 20012007 asD1907 017. DOI:
14、10.1520/D1907-_D1907M-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.1This document is not an ASTM stan
15、dard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all case
16、s only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D681 Specification for Jute Rove and Plied Yarn for Electrical and Packing Purpos
17、esD1059 Test Method for Yarn Number Based on Short-Length SpecimensD1578 Test Method for Breaking Strength of Yarn in Skein FormD1909 Standard Table of Commercial Moisture Regains for Textile FibersD2257 Test Method for Extractable Matter in TextilesD2260Tables of Conversion Factors and Equivalent Y
18、arn Numbers Measured in Various Numbering SystemsD2258 Practice for Sampling Yarn for TestingD2494 Test Method for Commercial Mass of a Shipment of Yarn or Manufactured Staple Fiber or TowD4849 Terminology Related to Yarns and Fibers3. Terminology3.1 For all terminology relating to D13.11, CottonD13
19、.58, Yarns and Fibers, refer to Terminology D4849.3.1.1 The following terms are relevant to this standard: commercial allowance, commercial moisture regain, direct yarnnumbering system, indirect yarn numbering system, linear density for fiber and yarn, skein, yarn number, yarn numbering system.3.2 F
20、or 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 from themass and length of the skein. In some options, the skein is scoured before weighing, and, depending
21、 on the option chosen, the massof the skein may be determined after oven drying, or after conditioning.5. Significance and Use5.1 Test Method D1907 is considered satisfactory for acceptance testing of commercial shipments, since it has been usedextensively in the trade for that purpose.5.1.1 In case
22、 of dispute arising from differences in reported test results when using Test Method D1907 for acceptance testingof commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical biasbetween their laboratories.5.1.2 Competent statistical
23、assistance is recommended for the determination of such a bias. As a minimum, the two partiesshould take a group of test specimens that are as homogeneous as possible, and that are from the same lot of the material inquestion. The test specimens should then be randomly assigned in equal numbers to e
24、ach laboratory for testing. The average resultsfrom the two laboratories should be compared using statistical analysis for unpaired data, and an acceptable probability levelchosen by the parties before testing begins. If a bias is found, either its cause must be identified and corrected, or the purc
25、haserand supplier must agree to interpret future test results for that material with consideration to the known bias.5.2 This test method is intended primarily for the determination of the average linear density of yarns. However, the variationsidentified by the results may also provide useful infor
26、mation. If the coefficient of variation is to be calculated, each skein must beweighed separately, and a larger number of skeins will need to be tested (as compared to the number of skeins to be tested for thedetermination of the average yarn linear density alone).5.3 This test method includes seven
27、 options, depending on whether the yarn is scoured before weighing, weighed in theconditioned or oven-dried state, or whether or not the results obtained are adjusted for commercial moisture regain, or acommercial allowance. Option 1 (unscoured, conditioned yarn) is generally used for yarns spun on
28、the cotton system, whileOptions 6 and 7 (scoured, oven dried yarn, plus commercial moisture regain, or allowance) are generally used for filament yarns,or yarns containing wool fibers. The specific options to be used in any instance shall be agreed upon by the parties, or as prescribedin test method
29、s or tolerances, for filament yarns, or for yarns spun from specific fibers. tolerances.5.4 In Options 2, 3, 5, 6, and 7, an oven-dried sample is obtained by exposing the yarn in an oven with a supply of air at standardtextile testing conditions, as described in 6.3.6. Apparatus and Reagents6.1 Reel
30、:6.1.1 GeneralA hand reel or motor driven reel having a perimeter of 1.000 m or 1.500 yd. with a tolerance of 60.25 % isrecommended. By prior agreement, reels having a perimeter of between 1.0 and 2.5 m (1.51.5 and 3.0 yd)yd may be used. Thereel shall be fitted with a traversing mechanism that will
31、avoid bunching successive wraps of yarn, and with an indicator of thelength wound. A warning bell that rings at a specified length, is also 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
32、 perimeter of the reel by winding a 0.6 cm. (0.25 in.)0.25 in. wide steel measuringtape around the reel. Tension the tape prior to directly reading the circumference of the reel, by attaching a 0.5 kg (1.0 lb)1.0 lbweight to the end of the tape. Repeat this measurement near each end of the bars of t
33、he reel, and in the center. If the circumferenceat any of these areas is outside the limits of 1.000 6 2.5 mm (1.500+0.1 in.),1.500 + 0.1 in., adjust the fly wheel to bring themeasurement(s) within the limits.6.1.3 Yarn TensioningThe reel shall be fitted with either a positive feed system at a contr
34、olled tension of 0.5 cN/tex (0.050.05D1907/D1907M 122gf/ tex)tex or with an adjustable tension device. The length of the skeins should be checked, and variations in length not be allowedto exceed 60.25 % (See Annex A1).6.2 BalanceFor the determination of average yarn linear density, a balance of sui
35、table capacity, graduated in grams or grains,with a sensitivity of 1 part in 1000 should be used. If single skeins are weighed, a balance graduated directly in yarn linear densitymay be used.NOTE 2The 1:1000 balance sensitivity is needed to ascertain the completion of conditioning, or oven drying. F
36、or subsequent weighings of skeins,a 1:500 sensitivity has been found to be sufficient.NOTE 3For the calculation of the variation of yarn linear density, a 1:100 balance sensitivity is sufficient to weigh individual skeins, after the skeinsare conditioned, or oven-dried.6.3 Drying OvenAn oven, ventil
37、ated and capable of being controlled in a temperature range of 105 6 3C (221221 65F),5F, is required to dry the skeins. The oven should be of sufficient design to facilitate the free passage of air through thespecimens, and should be supplied with a current of air sufficient to change the air in the
38、 oven once every 4 min. The specimensshall be protected from any direct heat, radiating from the heating units of the oven.Air supplied to the oven shall be at the standardatmosphere for testing textiles. The oven may be provided with facilities to shut off the air current and weigh the specimens,wi
39、thout removing them from the oven.6.4 Facilities for Scouring (Options 4, 5, 6, and 7), as indicated in X2.2Appendix X2, or in Sections 6.1 and 6.3 of Test MethodD2494.6.5 Weighing Cans, with tight fitting lids, and of sufficient size to hold all skeins, or groups of skeins (Options 2, 3, 5, 6, and7
40、), if the weighing is to be done outside the oven. Weighing bottles with ground-glass stoppers may also be used.6.6 Auxiliary Facilities, suited to the specimens and options used, such as sample supports, tared wire gauze baskets ofcorrosion resistant metal, dessicators of sufficient size to hold th
41、e weighing cans or bottles, and an efficient dessicant.7. Sampling7.1 Lot SampleAs a lot sample for acceptance testing, take at random the number of shipping units directed in an applicablematerial specification, or other agreement between the purchaser and supplier, such as an agreement to use Prac
42、tice D2258.Consider cartons or other shipping units to be the primary sampling units.NOTE 4An adequate specification or other agreement between the purchaser and the supplier requires taking into account the variability betweenshipping units, between packages or ends within a shipping unit, and betw
43、een specimens from a single package, to provide a sampling plan with ameaningful producers risk, users risk, acceptable quality level, and limiting quality level.7.2 Laboratory SampleAs a laboratory sample for acceptance testing, take at random from each shipping unit in the lotsample the number of
44、packages or ends directed in an applicable material specification, or as agreed to between purchaser andsupplier (such as an agreement to use Practice D2258). Preferably, the same number of packages should be taken from eachshipping unit in the lot sample.7.2.1 Average of Yarn Linear DensityWhen onl
45、y the average of the yarn linear density is to be determined, take a laboratorysample as follows: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 v
46、ariability of the linear density of yarn areto be determined, take a laboratory sample of 30 packages. If possible, take an equal number of randomly selected packages fromeach case in the lot sample.7.3 Test SpecimensTest one skein from each package in the laboratory sample.NOTE 5Since the variation
47、 in yarn linear density is usually higher between packages than within packages, no appreciable improvement in precisioncan be expected by testing more than one skein from each package.7.3.1 An exception to the information provided in Note 5 may occur in packages of filament yarns; consistent differ
48、ences in yarnlinear density are sometimes present between yarn on the outside of the package, as compared to yarn on the inside. If suchdifferences are suspected, test more than one skein from each package, without reducing the number of packages sampled fortesting, taking skeins at intervals throug
49、hout the packages.8. Conditioning8.1 Before reeling test skeins, condition yarn in skein form in the standard atmosphere for testing textiles for a minimum of 1h, and yarn on packages for a minimum of 3 h. Additionally, prior to testing, preconditioning of the test skeins may be requiredfor Option 1, but is not necessary for Options 2 through 7.NOTE 6For Options 2 through 7, where the yarn is scoured or oven-dried after reeling, the conditioning prior to reeling is required to ensure a correctskein length.D1907/D1907M 1239. Procedur
