A computer based interactive approach to a two-stage cutting stock problem

In this article, the authors present a computer interactive system, developed for a Portuguese steel manufacturer operating at the retail level. The production process includes not only cutting operations, which are performed in two different stages, but also intermediate processing. Minimization of trim loss and reduction of set-up are primary objectives in every cutting stock problem. In this system, there is also another important objective, which is the minimization of the number of intermediate rolls. Because these objectives may be conflicting, a balance between them may be necessary. Another feature of the system is that the weight of the raw material rolls may vary slightly. New models were built and integrated in an interactive computer system, developed for a microcomputer. In each planning period, the system is used to establish a couple of dozen operational cutting plans, one for each different raw material. The results obtained are slightly better than those previously obtained by experienced schedulers.