Forming Mechanism About Axial Balance and Axial Movement of Asymmetric Cross Wedge Rolling

It is known that the key problem of cross wedge rolling (CWR) asymmetric shaft parts is to keep the balance of axial force and control the movement of the parts in axial. Aiming at rolling the qualified shaft parts, the balance mechanism of the axial force and the mechanism of the movement in axial are studied in this work. The FE model of asymmetric CWR was established and the axial force of the parts suffered in asymmetric and symmetric process was analyzed comparatively. It was found that the axial force in asymmetric process could be self-adjusted. Also, the axial displacement of the tracking point was analyzed comparatively. The comparative results led to the fact that the instantaneous stretch increased in weak-side while it decreased in strong-side, which were verified by experiments. Moreover, the reasons of balance of axial force by self-adjustment during non-steady state rolling and the part movement in steady state rolling were analyzed. Above theoretical study improves the forming theory of asymmetric cross wedge rolling and provides a practical method for rolling the qualified asymmetric shaft parts.