Determination of turret configuration and hit sequence for optimization of NC turret punch press operation

Abstract

This paper addresses the problem of minimization of the time taken to process sheet metal stock on an NC turret punch press. The processing lime of a sheet depends primarily on (1) the sequence in which the hits are made and )2) the arrangement of tools in the turret. Minimization of the processing time for a sheet requires the simultaneous solution of these two coupled sub-problems. Motivated by this view, the paper proposes three heuristics to find a hit sequence and a turret configuration that together minimize the processing time for a sheet. A comparison of the performance of these heuristics is provided. In addition, the paper examines some issues not considered in prior research but essential to the accurate modelling of the operation of an NC turret punch press, and discusses their incorporation in the proposed heuristics.