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 CV _t , CV _s and CV _h , respectively, were investigated in detail. Results indicate that the CV _s of an uneven yarn always coincides with the irregularity of the yarn hairiness. More specifically, the CV _t of a yarn cannot be better than those of both yarn hairiness and stem (CV _h and CV _s ), even if one of them is excessive. It is rare for CV _t to be higher than CV _s after removal of yarn hairs. In particular, it is irrational for the CV _t value to be higher than both CV _s and CV _h , which prompts a rethinking of the exact distribution of yarn hairs on the yarn body.