Modelling and simulation of guide roller control mode for vertical hot ring rolling process

Abstract

The guide roller plays an important role in maintaining forming stability and ensuring the roundness of ring profile in the ring rolling process. In the study geometrical models of single fixed guide mode (SFGM) and single follow‐up guide mode (SFUGM) of the vertical hot ring rolling (VHRR) process are established, coupled thermal–mechanical finite element models of VHRR are then constructed and the rolling process of a rectangular section ring is simulated. The results obtained show the following aspects. First, the stress in the ring rolled by SFGM is larger than that in the ring rolled by SFUGM. The shape of deformation zone in the ring rolled by SFGM becomes slanting while that in the ring rolled by SFUGM remains vertical. Second, the strain and temperature are non‐uniform in the ring rolled by the two guide modes. Moreover, the strain and temperature in the ring rolled by SFGM are higher than those in the ring rolled by SFUGM. Third, the temperature of the ring rolled by SFGM on the outside surface is initially higher than that on the inside surface but this is reversed in the later rolling stage. However, for the ring rolled by SFUGM, the temperature on the outside surface is higher than that on the inside surface throughout the whole rolling stage. Fourth, calculated results of roundness error show that the roundness error of the ring rolled by SFGM is larger than that of the ring rolled by SFUGM. A ring rolling experiment on the prototype of D51‐350 vertical ring rolling mill was carried out and results showed that the formed ring had a good forming quality.