Research on fiber tension at asymmetric spinning triangle using the finite-element method

Spinning triangle is a critical zone in the ring spinning process of staple yarn, whose geometry influences the fiber tension distribution in the spinning triangle directly and determines the spun yarn qualities. In ring spinning, the spinning triangle is often asymmetric due to the inclination angle of the spinning tension or the migration of the axis fiber at the front roller nip. Therefore, in this paper, the fiber tension distributions in the asymmetric spinning triangle due to the migration of the axis fiber at the front roller nip were studied using the finite element method (FEM). In the direct finite-element model, the initial strain of the axis fiber is set as zero, and the accidental fiber tensions would be produced due to the asymmetric distributions of the initial strain on fibers in the two sides of the spinning triangle. Then, an effective finite-element model of the asymmetric spinning triangle with right (left) axis fiber migration for calculating the fiber tension is built by composing an...