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ASTM International

Standard Test Method for Twist in Single Spun Yarns by the Untwist-Retwist Method
 N D1422/D1422M

Annotation

This test method2 describes the determination of twist in single spun yarns when only an approximation of the true twist is required.

NOTE 1—For a more accurate method see Test Method D1423.

This test method is applicable to spun single yarns in continuous lengths, and also to spun yarns raveled from fabrics, provided specimens at least 200 mm [8 in.] long can be obtained.

This test method has been found satisfactory for use in determining the approximate twist content in single ring spun yarns of all types and fiber contents, but not in open-end spun yarns.

This specification shows the values in both inch-pound units and SI units. The "inch-pound" units is the technically correct name for the customary units used in the United States. The "SI" units is the technically corrected name for the system of metric units known as the International System of Units. The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2 This test method is commonly designated by the less precise term "Untwist- Twist Method."