Optimization of Fiber Friction, Top Arm Pressure and Roller Setting at Various Drafting Stages

The influence of fiber friction, top arm pressure and roller setting at various drafting stages (draw frame, speed frame and ring frame) on yarn properties was studied. The Box and Behnken factorial design was used to optimize these three factors for better yarn quality. In each case, the optimum conditions within the industrially acceptable limits of the process were established. The results presented here show that fiber-to-fiber friction can be the dominant factor in determining the tensile properties of ring spun yarns. It is observed that a higher fiber friction value gives higher yarn tenacity and lower hairiness. On the other hand, a lower fiber friction value gives better evenness and lower imperfections. The top arm pressure and roller setting influence the yarn properties at all three drafting stages almost in similar way. With the increase of top arm pressure and roller setting the yarn tenacity increases initially up to a point and then decreases. Yarn unevenness, imperfections and hairiness shows an initial decrease up to a point with the increase of the above two parameters. In general, the moderate level of top arm pressure and roller setting gives better results.