Effect of Single and Ply Twists on the Properties of a 31 /2 Carded Cotton Yarn

Abstract

The effect of single and ply twists on the properties of a 31/2 cotton carded yarn was studied. A widely grown cotton variety (Deltapine) of average fiber properties was spun into a 31/1 yarn (Z twist) using a range of twist multipliers (2.9-6.9). Each single yarn twist multiplier construction was then 2-ply twisted (S twist) with a range of twist multipliers (1.9-7.9). Maximum ply strength was obtained when low-twist single yarns were 2-ply twisted with a high twist multiplier. Maximum elongation at break was obtained with a similar single-ply twist construction. For certain twist constructions single and ply twist may be varied within reasonable limits without materially decreasing strength. When the same twist multiplier was used in the single and ply yarn, maximum ply yarn strength was realized with that twist multiplier which resulted in maximum single yarn strength. Elongation is related linearly and directly to equivalent twist multiplier constructions. The ratio of ply to single yarn strength, based on maximum ply yarn strength, was highest when single yarn strength was lowest (low twist), decreased rapidly as the single yarn strength approached maximum, became approximately constant in twist combinations resulting in single yarns of maximum strength, and increased slightly as single yarn strength decreased (very high twist).