Original article Research on mechanical properties of the Siro-spinning triangle using the Finite Element Method

Siro-spinning (two-strand yarn spinning) is a new kind of modified ring spinning method, which is achieved by feeding two rovings into the apron zone at a predetermined separation simultaneously. There are three spinning triangles, including two primary spinning triangles and one final spinning triangle, in Siro-spinning. Therefore, in this paper, the quantitative relationships between the mechanical performance of a Siro-spinning triangle and the spinning parameters are investi-gated by using the Finite Element Method. The finite element model of the Siro-spinning triangle is constructed under the assumption in which the constituent fibers are considered as three-dimensional elastic beam elements with tensile, compressive, torsion, and bending capabilities. Three different cases where the ends of all fibers, the initial strain of all fibers, and the angle between any two adjacent fibers gripped in the front roller nip distribute evenly are discussed. Meanwhile, in each case, three different cases where the initial strains of the shortest boundary fiber, the central fiber, and the virtual fiber on the direction of yarn spinning tension are set as zero are discussed respectively. Then, taking the spinning triangle in Ne40 (14.6 tex) cotton Sirospun yarn as an example, the fiber tension distribution and fiber torsion distribution in the corresponding Siro-spinning triangle with and without fiber buckling are numerical simulated. It is shown that the fiber tension distributions are influenced by the setting of the fiber initial strain, while the magnitudes of fiber tension are not affected. Finally, Ne40 cotton ring yarns were spun on an EJM128K ring spinning machine, and the properties of spun yarns were evaluated and analyzed according to the simulation results