STRUCTURE ANALYSIS AND DESIGN OF RING SPINNING SLUB YARN

The objective of this paper is to investigate the structure and critical twist of ring spinning slub yarn. The causes are theoretically analyzed, which is the fiber. length brings about interim state between slub section and base yarn section. Based on drafting theory, the interim state length is equal to the fiber length in ideal drafting. So the minimum slub length is the fiber length for ring spinning slub yarn. The interim state length influences on slub yarn two parameters i.e. slub multiple and base yarn linear density. But the interim state length has no influence on slub length, slub space and slub yarn linear density. The influence of four parameters (fiber tenacity, slub multiple, slub distance and slub length) on the critical twist was analyzed. We use nine different specifications of slub yarn to establish the relationship between the critical twist and the parameters of slub yarn. Finally, a multiple linear regression equation between the critical twist and the four parameters is established. The result can be used to instruct the design and production of the ring spinning slub yarn.