Process optimization method for cold orbital forging of component with deep and narrow groove

During cold orbital forging of component with deep and narrow groove, the metal flow is complex and it may lead to some defects of underfilling and folding. Moreover, the stress state of the tool, which has a long and thin boss corresponded to the deep and narrow groove of component, is poor and thus the life span of the tool is low. Aimed at these issues, this paper presents a process optimization method for cold orbital forging of component with deep and narrow groove. Firstly, three kinds of metal flow modes are presented according to the preform and tool geometries. Then, the cold orbital forging processes under three kinds of metal flow modes are analyzed by FE simulations and the mechanisms for forging defects of underfilling, folding and poor stress state of the tool are revealed. It is found that the horizontal stress imbalance of the long and thin boss of the tool is the main reason for its poor stress state. To improve the stress state of the tool, a new idea is motivated, i.e., it is through controlling the metal flow to balance the horizontal stress of the long and thin boss of the tool. Finally, the optimization method for the preform and tool is presented to eliminate the forging defects. The experiments are also carried out to verify the presented process optimization method.