Abstract:

Inorder to determine the draft ratio of back drafting zone of different slivers during drawing process efficiently, the tensile method was used to simulate drafting of the back drafting zone on a drawing frame. Cotton, polyester and rayon slivers were used in the experiments, reapectively. The results show that tensile curves and drafting force-drawing multiple curves are very similar. The draft ratio translated from the crutical elongation in tensile stress-strain curve is very close to the one calculated from the fitting cubic equation of the experimental data in the drafting force test when the maximum drafting force occurs, and the coeficient of the variation of the drafting force and output slivers unevenness are both low at the critical draft ration. The draft ratio of back drafting zone, therfore, can be designed according to the tensile curves. The result provides a certain reference for the rapid offline design on the draft ratio of the back drafting zone on drawing frame.

Key words: drawing frame, tensile, drafting, draft ratio of back drafting zone, sliver