Changing Yarn Hairiness During Winding— Analyzing the Trailing Fiber Ends

The change mechanisms of staple yarn hairiness during the winding process are studied using some previously published theories on yarn structures. Of the three kinds of yarn hairiness, the one formed by trailing and protruding fiber ends is analyzed first in terms of the interactions of the fiber ends, the tension disk, and the grooved drum. The various actions on the yarn during the winding process are identified and categorized into two groups: the one pulling the fiber ends and the other providing the resistance. By defining a ratio of the two groups of forces, a criterion of whether a fiber can be pulled out is established. This criterion is then applied to the tension disk and grooved drum, the main sites where actions occur, to investigate the impact on yarn hairiness. The influences of some important parameters including the yarn twist factor, the embedded fiber length, the frictional coefficients, and the size of the cheese are examined.