Ring rolling process and apparatus for ring rolling

Abstract

A ring rolling process and corresponding apparatus are disclosed. A ring shaped workpiece is provided, the ring shaped workpiece having a principal axis, an inner radial surface, an outer radial surface, a first axial surface and a second axial surface. The workpiece is subjected to radial pressure between a forming rollacting on the outer radial surface and a mandrel rollacting on the inner radial surface, at a radial roll bite region. A first axial rolland a second axial rollare provided at the first axial surface and the second axial surface respectively, to subject the workpiece to axial pressure. The first and second axial rollsare provided at an angular position, measured around the workpiece and with respect to the principal axis, within ±10° of said radial roll bite region. Multiple circumferential constraint rolls are provided around the outer radial surface or inner radial surface. In order to control the cross sectional shape of the workpiece, the mandrel rolland/or the forming rollhas a projecting portion for contact with the workpiece, the projecting portion having an axial extent which is smaller than the axial height of the workpiece, the mandrel roll and/or forming roll being axially moveable relative to the workpiece.