Progressive Die Strip Layout Optimization for Minimum Unbalanced Moments

Abstract

Progressive die stamping is a forming process that uses a series of stamping stations to perform simultaneous operations as the sheet is transported incrementally through the die. Designing of progressive die sets and evaluation of the operation for highly complex workpieces are time consuming and iterative at the early stages in the product design. The progressive die design starts with 3D modeling of the part and continues with process sequence planning and strip layout. The strip layout is usually performed manually by experienced progressive die designers. This process begins with unfolding the part and constructing the required part geometry with a series of forming operations. In this study, the same process steps have been used to automate the progressive die design for a given part and stamping press capacity. Therefore, the strip layout already considers the scrap and press tonnage minimizations. A genetic algorithm is used to optimize the strip working sequence with the objective of minimizing the moment difference between two sides of the die. A moment-optimum strip layout will extend the life expectancy of the die, and the maintenance cost will be lowered, particularly for high production rate components.