Investigation into novel drafting systems on ring spinning frame for improving yarn properties

Abstract

During the spinning process, the drafting process plays an important role because it is closely linked with yarn properties. In this study, two different bottom pins (N–A and N–B) based on a novel drafting device were designed. The simulation results of drafting forces between N–A and N–B demonstrate that N–B shows higher drafting force than N–A at the same draft ratio. Specifically, the drafting forces of both devices show an increasing trend as the front draft ratio increased. In experiments, 14.7 tex and 18.5 tex yarns were spun by N–A and N–B, respectively. The experimental results reveal that N–B produces yarns with better properties, including yarn evenness, imperfections and tenacity, compared to N–A. Notably, the evenness and imperfections of yarns spun by N–B achieve advanced levels and the characteristics of yarn tenacity are close to advanced levels. The experimental results verify that different drafting forces between N–A and N–B devices have an important impact on the yarn evenness, imperfections and tenacity, but not on the hairiness.