Process-induced defects in an L-shape profile ring rolling process

The ring rolling is a process of gradually forming the cross section of the ring material according to the outer shape of the working roll. In this study, process-induced defects in L-shaped cross section ring rolling process have been analyzed. Major defects in the L-shaped ring rolling process include folding, unfilling and groove on the bottom surface of the material. In order to understand the formation mechanisms of process-induced defects, finite element analysis and physical modeling have been performed at various processing conditions. For the process analysis, the effects of process variables such as blank geometry, dimension and rotation speed of working roll, mandrel feed speed and working temperature on the generation of defects have been investigated. From the analysis results, methodologies to prevent process-induced defects are proposed and validated by shop-floor ring rolling operations.