Studies on the short-term Irregularity of Supn Yarn (Part 3) Effect of the break draft and tensor opening on the short-term irregularity

방적사의 단주기 불균제도에 관한 연구 -제3보 드라프트 배분과 텐서오프닝이 단주기 불균제도에 미치는 영향-

The authors investigated the yarn irregularities caused by the different break drafts i.e., 1.21, 1.38, 1.65, 1.91, 2.20, the different tensor openings i.e., 2.5, 3.0, 3.5, 4.0, 5.0mm, and the results were as followings; 1. The effect of break draft on the irregularity of spun yarn(U%) was significant at the 99% level and the minimum irregularity was obtained with the break draft of 1.38 for CD30's and CM38's, and with the break draft of 1.21 for P/C45's. 2. Irregularity of spun yarn was increased as the tensor opening was increased, and the increasing rate was the largest at the minimum value of break draft i.e. maximum value of main draft. 3. Total added irregularity(above the normal curve on the spectrum) was significantly increased as the break draft was increased. The minimum value of total added irregularity was obtained with the break draft of 1.38 for CD 30's and CM 38's, and 1.21 for P/C 45's. Total added irregularity was also significantly increased as the tensor opening was increased. 4. The effects of break draft and tensor opening on the short-term added irregularity were very significant at the 99% level. Short-term added irregularity was decreased as the break draft was increased. It was also increased as the tensor opening was increased. 5. The effect of break draft on the long-term added irregularity was very significant at the 99% level. Long-term added irregularity was increased as the break draft was incresed, and its increasing rate was the largest for CD 30's and the smallest for P/C 45's. And the long-term added irregularity was not changed as the tensor opening was increased. 6. IPI value (thick places and thin places) was increased as the break draft was increased, and it was minimum with the beak draft of 1.38 for CD 30's and CM 38's, and 1.21 for P/C 45's. It was also increased as the tensor opening was increased. 7. There was no significant change in single strand strength for all kinks of spun yarns with different break drafts and different tensor openings.