ASTM International

Standard Test Method for Linear Density of Yarn (Yarn Number) by the Skein Method
 N D1907/D1907M

Annotation

This test method covers the determination of the linear density of all types of yarn in package form, subject to the limitations of size and stretch given in 1.2 and 1.3. Provision is made for expressing yarn linear density in all the traditional yarn numbering systems.

This test method is applicable to yarns that stretch less than 5 % when tension on the yarn is increased from 0.25 to 0.75 cN/tex [0.25 to 0.75 gf/tex]. By mutual agreement, and use of a lower than specified reeling tension, this method may also be adapted to measure the linear density of yarns that stretch more than 5 %, under the above force.

This method is applicable to yarns finer than 2000 tex. However, it may be also adapted to coarser yarns by the use of skeins of shorter than specified lengths, and alternate reeling conditions, agreeable to the interested parties.

Depending on the procedure used to calculate the 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.

Unscoured Yarn:

Option 1—Yarn at equilibrium with the standard atmosphere for testing textiles.

Option 2—Oven-dried yarn.

Option 3—Oven-dried yarn, plus commercial moisture regain.

Scoured Yarn:

Option 4—Scoured yarn at equilibrium with the standard atmosphere for testing textiles.