A Study on Open-End Spinning

Abstract

The concept of the fiber separation probability was introduced to the open-end spinning system by Kawabata et al.[2] Although they prepared the theory of separation at one point, this paper deals with the theory under the assumption of zone draft, and the draft ratio needed to separate a sliver into individual fibers by air-flow was calculated in ideal drafting case with random sliver model.Not only the ideal separation but also separation in groups were observed by high-speed photography [Note 1]. Silvers may be separated in groups because fibers are apt to stick each other and to be entangled with each other [Note 2]. This phenomena was re-examined by Monte Carlo simulation analysis on a digital computer. Separation in groups, while it is one of the origins of yarn unevenness, makes a handy means to reduce the draft ratio needed to avoid false-twist in open-end spinning.