Development of Newly Designed Oil Film Bearing and Improvement of Gauge Accuracy

Abstract

Thickness accuracy has markedly been improved by the application of large mill modulus, but this causes eccentric behavior of backup roll in a mill using oil film bearing, leading to thickness fluctuation in the rolling direction. It has been found that the eccentric behavior of the rolls is caused by the deformation of the sleeve generated at the groove of the key connecting the sleeve and the tapered roll neck, and the resultant fluctuation in oil film thickness.
A theoretical analysis has been made on this phenomenon assuming the journal as an elastic body, and newly designed oil film bearing (keyless bearing) has been developed, which has no key groove at the tapered roll neck.. As a result, gauge fluctuation has been minimized and a considerable advantage obtained.