Effects of forming parameters on coupled thermomechanical behaviours in combined ring rolling

Abstract

Combined ring rolling (CRR) is a new method for manufacturing rings which feature thick walls, deep grooves and small bores. Compared with general ring rolling, two driven rolls with fixed axes are added to control the circumferential metal flow and form the deep groove. Rolling force and energy, strain distribution uniformity, and temperature distribution uniformity are very important to the process design and forming quality of rings, which are sensitive to rolling parameters, such as motions of the driving roll, temperature and friction. In this paper, the reasonable ranges of feed parameters were determined based on stable rolling conditions. A reliable 3D coupled thermomechanical finite element model was then established using the dynamic explicit code ABAQUS/Explicit and the effects of rolling parameters investigated, including rotational velocity of driving roll n, the feed velocity of the driving roll v, initial temperature of workpiece and friction among the rolls and the ring. The research results are significant for process design and forming optimisation of CRR production.