Analysis of deformation characteristics of twisted woolen yarns

Abstract

Defining thresholds for yarn strain in manufacturing process is crucial for appropriate adjusting these processes and keeping high yarn quality. That is the main reason why this issue has brought so much intention. The knowledge of elasticity limits and yield points is very important for the optimization of the production process and further twisted woolen yarns processing. Therefore, this paper defines limits for elasticity, yield points and breaking forces of woolen yarns with longitudinal masses of 21x2, 23x2 and 25x2 tex, obtained by two-for-one twisting method. Also, analyzed was the interrelationship between the forces and the elongations at elasticity limits, yield points and breaking force of these yarns. Besides, on the basis of experimental results and equations, real mathematical dependences are set, which can be used for projecting forces and elongations of woolen yarns at elasticity limits, yield points and breaking limits.