Analysis of a torque equilibrium model and the optimal strip working sequence for a shearing-cut and bending progressive die

Abstract The shearing force in the shearing-cut process for a shearing-cut and bending progressive die is far greater than the strip bending force. In this paper, the equation for torque equilibrium is first established. The heuristic rule is then adopted to locate the die center of the shearing-cut and bending progressive die and an offset displacement is set (i.e. rough tuning). The algorithm of the static equilibrium is then used to conduct further fine-tuning of the die center to obtain the central pressure position of the shearing-cut and bending progressive die. The purpose is to reduce the time spent in adjusting the pressure center of the shearing-cut and bending progressive die. Finally, genetic-algorithms (GA) are applied as a solution tool in the analysis of the optimal strip working sequence possessing a smaller difference between the right and left torque in the shearing-cut and bending progressive die. This sequence can improve the approach of rough tuning by applying an offset displacement to the die center followed by further fine-tuning, as mentioned earlier. Instead, only fine-tuning of the die center is required to obtain the die’s central pressure with torque equilibrium for effective reduction of the time spent in adjusting the center of the shearing-cut and bending progressive die.