Two-stage optimized scheduling method and application for steelmaking and continuous casting

Steelmaking and continuous casting is a difficult process that is manually scheduled due to its overwhelming number of objectives and restriction factors. This paper provides a new method of two-stage optimized scheduling for steelmaking and continuous casting. In the first stage, a preliminary schedule is established based on the same usage rate of parallel machines and minimized time conflict. In the second stage, a linear programming model of elimination time conflict is established. By solving the two mathematical models, an operable schedule is produced. The method of two-stage optimized scheduling has been embedded a scheduling system which is also developed and successfully applied to a large steel plant in China. The industrial application has demonstrated that the proposed method cannot only meet the requirement of practical production, but also has a wide application in industry.