Numerical analysis and experiment on cross wedge rolling and forging for engine valves

The combination of cross wedge rolling (CWR) and forging is a new metal forming technique for producing engine valves. In this paper, the overall details of the combined CWR and forging process are described, and the important parameters that control the process are systematically discussed. An experimental method was developed under laboratory conditions. This method showed that the combined CWR and forging process could produce an engine valve with high manufacturing quality. Numerical simulations of the process were conducted using a commercial software (DEFORM) to show stress and temperature distributions in the rolled valve. In addition, the variations of forces and rolling torques during the process were analyzed. According to the experimental and numerical investigations, the combined CWR and forging process is a viable technique for enhancing the quality and productivity of engine valve products.