Geometry evolution prediction and process settings influence in profiled ring rolling

A kinematic-based analytical model was developed for estimating the geometrical expansion of profiled rings during the ring rolling process and validated against own and literature experimental results. The model, based on the volume conservation principle, describes the material redistribution between radial and circumferential directions due to the employed process parameters and friction conditions. The comparison between analytical and experimental ring diameters evolutions, carried out considering various materials, process conditions, and profiled ring shapes, showed maximum and average deviations equal to 4.9% and 2.1%, proving the reliability of the implemented kinematic solution. The penetration and biting-in conditions, well-known in flat ring rolling, showed to be applicable and effective also in profiled ring rolling, allowing to define the suitable ranges for the mandrel feeding speed and the main roll rotation speed. The proposed solution was utilized, coupled with thermo-mechanical FEM simulations, to investigate the influence of the ring preform shape and the process parameters on the geometrical expansion of both wall and flange of the ring during the process. Furthermore, the range of validity of the developed analytical model was investigated as well.