Theoretical study on a spinning triangle with fiber superposition

Abstract

In some new modified ring spinning systems, fiber superposition in the front nip line often exists, that is, each fiber in the spinning triangle is not distributed evenly, but some fibers are divided into substrands or bundles. Therefore, in this paper, a theoretical model of fiber tension distribution in the spinning triangle is proposed by considering the fiber superposition at the spinning triangle based on the principle of minimum potential energy. The symmetric and asymmetric spinning triangle due to the inclination angle of the spinning tension and the migration of the axis fiber at the front roller nip were all considered, and theoretical models of fiber tension distributions in the corresponding spinning triangles were given. The relationships between the fiber tension and the spinning triangle shapes were studied. Finally, as an application of the proposed method, ring spinning triangles the 14.6 tex (40S) cotton yarn spinning were taken as an example for the simulation. The numerical simulations of fiber tension distributions in the spinning triangle were presented and analyzed comparatively. In particular, the effect of both fiber superposition and the distance between two adjacent substrands in the front nip on fiber tension distributions were discussed. The results show that when there is fiber superposition in the front nip, comparing with the case that each fiber is distributed evenly, the tensile force of the two boundary fibers is decreased slightly, and the compressive force of the central fibers is also increased slightly, which leads to similar magnitudes.