Constraint Programming Approach to Steelmaking-making Process Scheduling

Abstract

This paper presents a constraint programming (CP) approach to optimal steelmaking process scheduling with constraints of processing time, limited waiting time between adjacent stages, serial batching, sequence independent setup time, release/due time, and with the objective of minimizing maximal total waiting time between adjacent charges in the same casts. The model and search strategies are proposed. Numerical experiments with the steel making process show that CP approach, under appropriate formulation and search strategies, can not only describe the problem exactly，but also can solve the problem more effectively and efficiently compared with classical exact algorithms and heuristic rules.