The measurement of fibre-withdrawal forces in simulated high-speed carding

Fibre withdrawal at high speeds is very common in fibre-opening processes such as carding. Understanding the effect of the withdrawal speed on the fibre-withdrawal force is of importance in improving the process productivity while controlling the level of associated fibre breakages. In this work, high-speed fibre-withdrawal forces were measured during a simulated carding process by using high-speed computer-data-acquisition techniques. There was no significant effect of withdrawal speed (up to 8 m/s) on the withdrawal-force level, and no fibre breakage occurred when the withdrawn fibre was not entangled. However, the configuration of the fibre assembly, particularly its degree of entanglement, plays an important role in determining the pattern and level of withdrawal forces. The peak withdrawal forces were found to increase with an increase in the fibre–pin contact angles and fibre-assembly density.