Abstract: The CC-HCR (continous costing hot-charge rolling) process in the steelmaking continuous casting production can be described as a kind of two-stage hybrid flow shop scheduling problem. A static and discrete-time integer programming model is established for it. By analyzing the characteristics of the problem in a new viewpoint, it turns out to be a three-stage hybrid flow shop scheduling problem with no-wait constraint. On this basis, two heuristic algorithms named JB and JBN are proposed. For the former, jobs are processed by problem-dependent heuristic rules. The backtracking is used to solve the constraints of limited buffers. For the latter, it is combined with NEH, which minimizes the idle time at the first stage as the objective function, adjusts the job sequence at the second stage, and improves the quality of the solution at the third stage. Furthermore, computational experiments are conducted to evaluate the effectiveness of these algorithms and it shows that they are feasible and effective. 

Key words: hybrid flow shop scheduling, limited buffers, heuristic algorithm