Product batching and batch sequencing for NC punch presses

This paper proposes a two-stage practical product batching and batch sequencing algorithm for NC punch presses used in the production of precision sheet metal electronics components. The first stage of the algorithm batches a given set of products in order to maximize the number of products in a batch as well as the tool magazine utilization. In this stage, tool magazine constraints such as number of available slots, size of slots, tool configurations and tool locations are taken into consideration. The resulting batches are passed to the second stage of the algorithm which sequences these batches. The sequencing is done by using the ‘nearest neighbour’ heuristic for the ‘travelling salesman problem’. Comparison of the new method with the procedure previously used by a manufacturer of such components demonstrated a significant reduction in setup times.