A comprehensive solution for continuous casting production planning and scheduling

Abstract

Production planning and scheduling in steelmaking-continuous casting (SCC) process consists of decision making about three important issues: consolidating orders into charges, grouping charges into casts, and scheduling the casts on machines. In contrast to earlier investigations that mostly focus on one of these issues, a comprehensive two-phase approach is presented in this paper in order to solve the whole problem. In the first phase, a continuous-time formulation is developed to determine what casts in what sequences should be scheduled on which machines. The solution obtained is then used as an optimal framework to create the final schedule in the second phase where the assignment rules embedded in a heuristic algorithm are used to consolidate orders into charges and group charges into casts. This method has been successfully used for Mobarakeh Steel Company (MSC), the biggest steel enterprise in the Middle East. Computational experiments demonstrate that the proposed method substantially increases the productivity in MSC.