Research on mechanical properties of fibers at asymmetric ring spinning triangle using Finite Element Method

Abstract

In the ring spinning process of staple yarn, spinning triangle is a critical zone, whose geometry influences the mechanical properties of fiber in the spinning triangle directly. In the practical spinning, especially in some modified ring spinning systems, the spinning triangle is often asymmetric, in which the horizontal deviation of the twisting point is existed and lead to an obvious angle between the yarn spinning tension and the vertical axis perpendicular to the nip line. Therefore, in this paper, the fiber tension distributions in this kind of asymmetric spinning triangle were studied using the finite element method. In the direct finite element model, the initial strain of fibers in the two sides of spinning triangle is asymmetric, and corresponding accidental fiber tensions would be produced, which makes the fiber move to the middle of the spinning triangle and lead to inaccurate results. Therefore, in the paper, one new finite element model of the asymmetric spinning triangle with left (right) horizontal deviation was presented for calculating the fiber tension. In the model, an asymmetric spinning triangle with the same right (left) horizontal deviation was used to combine with the original asymmetric spinning triangle, and one axisymmetric quadrangle was built, and the symmetry axis is the central fiber. Then, the fiber tension and torque distributions in the spinning triangles of Ne40 (14.6 tex) and Ne60 (9.7 tex) cotton spun yarn were numerical simulated with different horizontal deviations and twist factors. Furthermore, the accuracy of the proposed finite element model in calculating the fiber tensions was validated by comparing it with the theoretical model built by the energy approach.

Keywords:

• Asymmetric spinning triangle
• fiber tension
• fiber torque
• horizontal deviation
• FEM

Additional information

Funding

This work was supported by the National Natural Science Foundation of P. R. China [grant number 11102072]; Natural Science Foundation of Jiangsu Province [grant number. BK20151359]; Prospective Industry-University-Research Project of Jiangsu Province [grant number BY2014023–13], [grant number BY2015019–10]; Prospective Industry-University-Research Project of Guangdong Province [grant number 2013B090600038]; Class General Financial grant from the China Postdoctoral Science Foundation [2015M581722]; Postdoctoral Research Funding Program of Jiangsu Province [1501146B].