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

The shearing force in the shearing-cut process for a shearing-cut and bendi ng progressive die is far greater than the strip bending force. In this pap er, the equation for torque equilibrium is first established. The heuristic rule is then adopted to locate the die center of the shearing-cut and bend ing progressive die and an offset displacement is set (i.e. rough tuning). The algorithm of the static equilibrium is then used to conduct further fin e-tuning of the die center to obtain the central pressure position of the s hearing-cut and bending progressive die. The purpose is to reduce the time spent in adjusting the pressure center of the shearing-cut and bending prog ressive die. Finally, genetic-algorithms (GA) are applied as a solution tool in the anal ysis of the optimal strip working sequence possessing a smaller difference between the right and left torque in the shearing cut and bending progressi ve die. This sequence can improve the approach of rough tuning by applying an offset displacement to the die center followed by further fine-tuning, a s mentioned earlier. Instead, only fine-tuning of the die center is require d to obtain the die's central pressure with torque equilibrium for effectiv e reduction of the time spent in adjusting the center of the shearing-cut a nd bending progressive die. (C) 2001 Elsevier Science B.V. All rights reser ved.