Cop and Cop Doubled Yarns

The twisting together of two or more threads to make a stronger or fancier thread. The operation consists in drawing threads from two or more cops or bobbins and twisting them together with the required number of turns per inch. This amount of twist varies considerably according to the purpose for which the yarn is required. Fewer turns are given to yarns for mercerising and hosiery, but yarns for sewing cotton or making healds require a great amount, 2/100's for instance, varies from 15 to 40 turns per inch. Many crepe yarns have 60 or more turns per inch. Doubled yarns possess greater strength and elasticity than a single yarn of the same weight (see Cop and Cop Doubled Yarns)

A mule machine used for doubling and twisting two or more threads together at one operation. It has similar general features to the spinning mule, but in the Yorkshire twiner, the spindle carriage is stationary and the creel carrying the supply yarns moves out while twist is inserted and in while the yarn is wound on the spindles in cop form. The supply yarns can be cops, cones or other packages. The yarns can be dry-twisted, or wet doubled, in which case a trough for water or a wetting-out compound is situated between two flannel-covered drag boards.