New Scheduling Algorithm for Shipping Operation in Steel Works

This paper proposes a new scheduling algorithm for shipping operations in steel works. In the shipping operation, steel products are handled by various kinds of machines, for example, overhead cranes in warehouses, special vehicles, forklifts and quay cranes. The operations of these machines affect each other and the situation makes the scheduling problem quite complicated. The proposed algorithm deals with shipping facilities which include warehouse buildings with plural cranes. Because some areas are accessible by plural cranes in the buildings, the movement of each crane is strictly restricted by others to prevent the collisions of cranes. The new algorithm is composed of two main steps to obtain efficient schedules and achieve short computation time. The first step assigns shipping jobs to time windows which are created by dividing the scheduling horizon, and then levels the workload of machines. The next step determines the order and operating time of jobs and develops a feasible schedule. The scheduling algorithm was applied to practical data and compared with real operations in this paper. The result shows the high performance of the new algorithm.