Optimization of Roller Forming Depth for Splined Mandrel Flow Forming

Flow forming is a metal forming method that forms a thick circular preform whose thickness and length are determined by its rotation and the two-dimensional motion of the rollers used. In this study, the optimal conditions for the forming depth for splined mandrel flow forming were obtained by the comparative analysis of actual forming data and analyzed data obtained from the flow forming process of a wet clutch housing of a transmission. It required a structure that can transmit a high torque and achieve mechanical reliability owing to the characteristics of agricultural tractors. The large forming load generated during the flow forming process acted as a major factor in the abrasion of the rollers and the mandrel. Moreover, an imbalance was caused by the difference between the loads of the three rollers, producing product defects. Therefore, the forming depth of the rollers was optimized as a variable using the finite element method to minimize the load applied to each roller and determine the balanced condition for the loads of the three rollers. The results of the forming depth analysis yielded forming depths of 4.2 mm, 2.4 mm, and 2.2 mm for the A, B, and C rollers, respectively. These results were confirmed by comparative verification with actual forming data.