Development of an ingenious composite roll system for merchant mill

摘要

A recent international trend is to improve performance of rolls for use in wire, rod, and bar mills and upgrade the quality of rolled products. Further, attempts are being made to replace the existing mono-block system of roll by a composite roll. In composite roll design, toughened and shock resistant arbor is used as the basic module on which a hardened and wear resistant rolling ring is securely clamped in proper place with the help of a suitable locking device. In the present work, an attempt is made to design and develop a composite ring roll system such that the roll assembly becomes dimensionully as well as functionally same as a conventional mono-block roll system. The friction lock mechanical shrink fit device proposed in the composite roll system, has been developed based on the basic principle of friction lock. Torque is transmitted by friction between the contact surfaces of locking system, roll shaft and rolling ring, resulting from tightening of the screws. A scale down model of a composite roll is developed and tested thoroughly to assess its torque transmitting capacity. The results demonstrate the feasibility of a composite roll.