Stamping strip layout for optimal raw material utilization

Stamping dies are used to produce very large numbers of identical parts from sheet metal. Due to the high volumes of parts produced, even small inefficiencies in material utilization per part can lead to very large amounts of wasted material over a die's life. This paper develops an exact algorithm for orienting the part on the strip to maximize material utilization. The algorithm optimally nests convex or nonconvex blanks on a strip and predicts both the orientation and strip width that minimize material usage. Technological constraints, such as blank orientation constraints due to planar anisotropy, are also incorporated into the algorithm. The algorithm's use is demonstrated with examples that show how sensitive material utilization can be to small changes in blank orientation in the die.