Effect of Suction Air Pressure in Friction Spinning on Yarn Properties

Abstract

We have studied the effects of suction air pressure on the structural parameters and mechanical properties of yarn. Changing the amount of suction air pressure improves the fiber extent in yam and yarn appearance. Therefore, photographic and fiber tracing methods are used to evaluate, respectively, yam appearance and fiber extent in the yam. To consider the effect of suction air pressure on yarn diameter, yam tension at the yarn-forming zone and yam diameter are measured simultaneously on a friction spinning machine using various levels of suction air pressure, and then the relationship between them is considered using the cross correlation method. The results show that at high suction air pressure, yarn di ameter, yarn unevenness, and yam irregularity decrease, while fiber extent in the yarn and twist efficiency increase. On the other hand, the value of the correlation coefficient demonstrates that there is a high correlation between variations in yam tension and yarn diameter. The results of yam mechanical property measurements show that at high suction air pressure, yam tenacity increases and yarn elongation decreases. Results are reported from experiments on 100% cotton yams.