Solving production scheduling with chain constraints in parallel production lines by column generation

This paper studies coil scheduling problem with chain constraints in the parallel continuous annealing production lines. The task of the problem is making schedules of the candidate coils in the inventory to minimize the total weighted completion times. In addition, some chain constraints should be satisfied, which has been determined by the practical production requirements. To solve this problem, column generation technology is adopted. And the pricing problem in column generation steps is solved by dynamic programming recursions. Branch and bound is used to obtain optimal solutions. Finally, the experiment results prove the efficiency of the algorithm.