Determination of a major design parameter for forward extrusion of spur gears

Abstract

In this study, a major design parameter was identified for cold forward extrusion of solid or hollow spur gears by investigating the effect of gear geometries and forming variables on formation of gear teeth by finite element simulations. A limiting extrusion ratio was determined for reducing the likeliness of underfilling in the die cavity. An equivalent radius of the cross-sectional geometry of a gear was also determined to predict the forming load requirement from an axi-symmetric approximation. Based on this approximation, a modified empirical equation was determined for simple determination of forming loads required.