Abstract

Ring rolling is an industrial bulk metal forming process for producing ring-shaped components of typical diameter 1-3m. Many of the final components such as turbo-machinery casings, flanges, bearings etc. have a shaped cross-section and yet the conventional process either produces ‘plain’ rectangular cross-section rings, wasting material, or requires expensive part-specific tooling to achieve a nearer to net shape ring. I will be presenting research I’ve carried out into ‘flexible’ ring rolling using a moving pair of radial rollers to achieve a shaped ring – akin to CNC machining. Such a process has complex mechanics and three key modes of deformation have been identified and analysed by an upper bound plasticity method, FEA and experiments on a model material. There appears to be an inherent limit on the range of geometries achievable because of difficulty controlling flow in axial and circumferential directions. Initial experimental research suggest that both a) toolpath b) additional tooling/constraints can potentially increase this range of shapes, ultimately making it a more viable industrial process.