Comparative Analysis of the Evenness Properties of Yarn Spun Using a Sinusoidal Pressure Bar

ABSTRACT

In this study, a sinusoidal pressure bar was used as a method of increasing the rear draft ratio to produce high-quality and high-efficiency yarn. Traditional-ring-spun yarn, traditional-pressure-bar-spun yarn, and sinusoidal-pressure-bar-spun yarn (denoted as TRSY, TPBSY, and SPBSY, respectively) were compared. A geometrical analysis indicated that the control stress of the sinusoidal friction field prevented the moving roving from twisting. Subsequently, the fiber strand was combed by the sinusoidal structure of the pressure bar, improving the straight parallelism of the staple fibers. Therefore, the accelerated points of the fibers were concentrated and moved forward. The mechanical analysis indicated that three-dimensional stress is conducive to the control of the floating fiber movement. A motion simulation analysis revealed the three-dimensional stress was higher than that of other scenarios of fiber movement control. In particular, the three-dimensional control stress contributed to an excellent yarn regularity of the SPBSY. Furthermore, a multigroup of cotton yarns were spun under different rear draft ratios with and without the traditional pressure bar or sinusoidal pressure bar to conduct confirmatory experiments. The experimental results indicated that the SPBSY had the minimum coefficient of variance and fewer imperfections under high rear draft ratios after compared with the TRSY and TPBSY.

摘要

在这项研究中, 正弦压力棒被用作一种增加后牵伸比的方法, 以生产高质量和高效率的纱线。比较了传统环锭纺纱线、传统压力棒纺纱线和正弦压力棒纺纱线(分别表示为TRSY、TPBSY和SPBSY)。几何分析表明, 正弦摩擦力界的控制应力阻止了粗纱的捻度向前传递。然后, 纤维束经正弦结构梳理, 提高了短纤维的伸直平行度。因此, 纤维变速点集中并前移。力学分析表明, 三维应力有利于控制浮游纤维的运动。运动模拟分析表明, 三维应力对纤维运动的控制明显大于其他方案。特别是三维控制应力使SPBSY具有良好的条干均匀度。此外, 在有无传统压力棒或正弦压力棒的情况下, 以不同的后区牵伸倍数纺制多组棉纱, 以进行验证性试验。实验结果表明, 与TRSY和TPBSY相比, SPBSY在高后区牵伸倍数下具有最小的CVm值和纱疵。

KEYWORDS:

• Ring spinning
• roller drafting
• sinusoidal pressure bar
• yarn evenness
• fiber movement
• accelerated-points distribution
• three-dimensional stress

关键词:

• 环锭纺
• 罗拉牵伸
• 正弦压力棒
• 条干均匀度
• 纤维运动
• 三维应力

Disclosure statement

No potential conflict of interest was reported by the author(s).

Highlights

• A novel method to improve the yarn irregularity under high draft ratio.

• Three-dimensional control model of fiber strands on drafting performance using the sinusoidal pressure bar was analyzed.

• The mechanical model and motion simulation for the fiber strands drafting under three-dimensional control was established.

• The unevenness of yarn spun with sinusoidal pressure bar was lower than other spun yarns under high draft ratio and the yarn irregularity (spun with sinusoidal pressure bar) remained stable as the increase of draft ratios

• Our study makes a significant contribution to the improve production efficiency, because it furthers the research on the yarn irregularity considering high draft ratios with varied stress control.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.