Open-end spinning concept has developed very
rapidly during recent years and this is because of its higher
productivity, better profitability and product quality. All
these demands could no longer be satisfied adequately by
conventional ring spinning system, because the
conventional spinning system has almost reached its
maximum utilization and there is little room for further
advancement. Li and Yan (1990) suggested that there were
many aspects of yarn quality but unevenness was the most
important because it was significantly correlated with the
fabric appearance and processing performance of the yarn.