Effect of process variables on properties of viscose vortex coloured spun yarn

Abstract

The vortex spinning machine has been used to develop coloured spun yarn which is commonly used in the yarn-dyed fabrics. Based on the Box and Behnkan Design, the regression analysis of response surface is used to study effects of process variables, namely nozzle pressure, yarn delivery speed and yarn count, on the properties of viscose vortex coloured spun yarn, such as yarn tenacity, elongation-at-break, evenness and diameter. The results show that different response variables are affected by different combinations of model terms. Yarn tenacity is significantly affected by yarn delivery speed, yarn count, and quadratic terms of nozzle pressure and yarn delivery speed. Yarn delivery speed has a nonlinear and marked effect on yarn elongation-at-break, while yarn count has a linear effect on yarn elongation-at-break. Yarn evenness is significantly influenced by nozzle pressure, yarn delivery speed and yarn count. There is interaction between yarn delivery speed and yarn count. Yarn hairiness H value is significantly affected by nozzle pressure and yarn delivery speed. Compared with yarn delivery speed, yarn count and nozzle pressure have a significant effect on yarn diameter.