Standard Test Method for Yarn Number Based on Short-Length Specimens

Importancia y uso:

5.1 This is a quick method used for the determination of the approximate yarn number of short-length specimens taken from packages or fabrics.

5.2 Because any error present in the reported length of the specimen is multiplied many times when calculating the theoretical yarn number using Eq 2 or Eq 3, it is extremely important that the length be measured as precisely as practicable.

5.3 For the analysis of fabrics, this test method is adequate for estimating the approximate yarn number of the yarn used to weave or knit the fabric, but the results obtained by this test method may not agree with the nominal yarn number of the yarns actually used to make the fabric because of the changes in the yarn number produced by the weaving or knitting operations, the finishing treatments, and the dissecting operations. This test method is suitable for the evaluation of yarns as they occur in the finished fabric, when that information is needed.

5.4 The yarn number obtained from the lengths taken from packages should not be expected to agree exactly with the values obtained by the use of the more precise methods of determining the yarn number included in Test Method D1907. If a sufficient number of consecutive specimens were tested, however, a close agreement with Option 1 of Test Method D1907 can be expected.

5.5 This test method is designed to measure the yarn number of the single yarns present as a component of a plied yarn and the yarn number of the original single yarns used to produce a high twist yarn for a crepe fabric.

5.6 This test method is not recommended for acceptance testing because of the short lengths used. In some cases, the purchaser and the supplier may have to test a commercial shipment of one or more specific materials by the best available method, even though the method has not been recommended for acceptance testing of commercial shipments.

5.6.1 In such a case, if there is disagreement arising from the differences in values reported by the purchaser and supplier when using this method for acceptance testing, the statistical bias, if any, between the laboratory of the purchaser and the laboratory of the supplier should be determined with each comparison being based on testing specimens randomly drawn from one sample of material of the type being evaluated.

Subcomité:

D13.58

Referida por:

D2259-21, D4031-07R18, D4029_D4029M-23, D5034-21, D0580_D0580M-24, D1907_D1907M-12R18, D0579_D0579M-24, D5034-21, D4849-21, D1907_D1907M-12R18, D1422_D1422M-13R20, D5446-08R19, D1423_D1423M-16R22, D1577-07R18

Volúmen:

07.01

Número ICS:

59.080.20 (Yarns)

Palabras clave:

yarn; yarn number;