A study on the relationship between irregularity and hairiness of spun yarns

In this study, Photoshop software was used to do image analysis on the photos of spun yarns. The result showed that yarn could be divided into two parts: the surface hairs and the stem. Based on this finding, a mathematical model of yarn unevenness was built to analyze the relationship between yarn unevenness and surface hairiness. The relationships among the coefficients of mass variance of the yarn, the stem and the surface hairs, expressed as CVt, CVs and CVh, respectively, were investigated in detail. Results indicate that the CVs of an uneven yarn always coincides with the irregularity of the yarn hairiness. More specifically, the CVt of a yarn cannot be better than those of both yarn hairiness and stem (CVh and CVs), even if one of them is excessive. It is rare for CV t to be higher than CVs after removal of yarn hairs. In particular, it is irrational for the CVt value to be higher than both CV s and CVh, which prompts a rethinking of the exact distribution of yarn hairs on the yarn body.