Optimum Drafting Conditions of Fine-Denier Polyester Spun Yarn

Abstract

For high quality fine denier polyester spun yarn, the ring spinning conditions have to be changed according to the twist factor and count of the roving. When the break draft is too low, the twisted roving cannot be sufficiently drafted in the back roller zone, resulting in thick places in the spun yarn. Too great an increase in the break draft and the back roller gauge will frequently cause a drafting wave in the drafted roving and consequently influence the quality of the spun yam. Also, it is better to increase the roller pressure 30-40% to control the fibers to yield a normal drafting behavior. The results of our investigations reveal that a break draft ratio of 1.3 and a 56 mm roller gauge in conjunction with a higher roller pressure (14 kgf) are the optimum spinning conditions for 0.8 denier polyester fiber roving of 0.6 TM and 0.354 g/m linear density.