Precision design of roll-forging die and its application in the forming of automobile front axles

Roll-forging is an efficient way to produce long or thin metal parts, and the design of rolling die is a sophisticated problem duo to the complex relative motions of dies and forging piece. In the first part of this paper, the kinematic relation between the surface of rolling die and that of forging piece during the roll-forging process are analysed, an approach for the precision design of rolling dies is presented based on the conjugate principle, and the surfaces of rolling die corresponding to the typical configurations of forging piece are investigated. In the second part of paper, the roll-forging technique for the manufacturing of automobile front axle is described, and the rolling dies for a representative front axle are designed, the practical applications of roll-forging technique confirmed the validity of the presented method.