Effect of Feeding ConditiQns at the Ringframe Upon Yarn Quality and Spinning Performance

Abstract

The paper deals with studies elucidating the effects of hank of the ingoing material and of doubling at the ringframe upon yarn quality and spinning performance under different spinning conditions obtained by varying the spindle speed and count spun. The results show that with coarse and medium mixings, the hank of the roving fed could be varied over a wide range without affecting yarn properties. The use of finer hank, however, led to a reduction in end-breakage rate in such mixings. With fine mixings, finer input hank and low ringframe drafts led to poorer yam quality and comparable or poorer spinning performance. Doubling at the ringframe improved the strength and regularity of yarns significantly in the case of coarse and medium mixings but only marginally in the case of fine mixings. The improved yarn quality thus obtained did nbt lead to better ringframe performance and the relative merits of single and double feeds in this regard were dependent upon mixing characteristics and spinning conditions. With coarse mixing, double feed invariably led to inferior spinning performance and the effect became highly pronounced when overspinning or at higher spindle speeds. With fine mixings, the two feeds were comparable at lower counts and spindle speeds but the deterioration in performance with increase of count or spindle speed was more rapid with double feed. In double feed spinning, end breakage rate was found to be lower on those spindles where the rovings were kept together by means of a cross-over of the strands in the break draft zone. The application of a condenser to keep the strands together was helpful in overcoming the deterioration in spinning per formance in double feed. The Minimum twist spinning test showed a better correspondence with end breakage rate under adverse conditions of spinning than under normal conditions.