Method for hot rolling planning considering material requirements of downstream production lines

Hot rolling planning in steel and iron production process is analyzed and a prize-collecting vehicle routing problem model with uncertain rolling planning numbers for hot rolling planning is presented with balancing the workloads of downstream production lines as one objective. The model considers the jump limit of discharging temperature, finishing rolling temperature and coiling temperature of adjacent slabs, the rolling position of slab surface grade and mix rolling of multiple rolling type slabs, but also considers the reasonable arranging of warm-up materials and staple materials. A two-stage algorithm based on Variable Neighborhood Tabu Search is designed to solve the model. Computational experiments with industrial data show the effectiveness of the proposed model and algorithm.