AN AXISYMMETRICAL FORGING APPROACH TO PREFORM DESIGN IN RING ROLLING USING A RIGID-VISCOPLASTIC FINITE-ELEMENT METHOD

In this paper, a new method for approximately predicting the deformati on of material in ring rolling is presented. The plastic flow of mater ial in ring rolling is assumed to be axisymmetric and thus the ring ro lling process is considered as a sequence of consecutive forging proce sses. The problem, having tool velocity as well as material velocity f ield as unknown variables, is formulated by an axisymmetric rigid-visc oplastic finite element method. The unknown tool velocity is determine d by making the circumferential stress on the ring cross-section exist in the range of user-specified values. The approach is applied to pre form shape design in ring rolling of bearing races. The predicted resu lts are compared with the experimental ones. It has been shown that th e approximate approach presented is useful for engineering design of p reform in ring rolling of bearing race-like rings. (C) 1998 Elsevier S cience Ltd. All rights reserved.