Optimization Method And System Development For Hot Rolling Planning Under Complex Process Constraints

Hot rolling plan is the core content and key technology of hot rolling production management.The quality of the hot rolling plan directly affects the smooth flow of process logistics before and after hot rolling,the efficiency of the rolling line,the cost of the rolls and the quality of the products.Hot rolling planning is not only related to hot rolling production,but also related to steelmaking-continuous casting production.At the same time,it is an urgent need of enterprises to develop a model-based hot rolling planning system to improve planning efficiency and plan quality.It is of great significance to reduce the production cost of enterprises,enhance the competitiveness of enterprises and improve the management level.This thesis relies on an integrated operations plan project of a software company in Shanghai.Based on the research of hot rolling production process,hot rolling plan preparation rules and process constraints,a double objective optimization mathematical model based on prize-collecting vehicle routing problem(PCVRP)was established.Among them,the target 1 is to minimize the jump penalty of the various attributes of the adjacent slab;the goal 2 is to minimize the total slab penalty that is not programmed into the hot rolling plan,that is,to make as many slabs as possible into the rolling plan.Since PCVRP is an NP-hard problem,When the number of slabs is large,it is difficult to solve accurately.Therefore,based on the model,the heuristic algorithm and the variable neighborhood search optimization algorithm are designed.The correctness of the model and the effectiveness of the algorithm are verified by field data test.The hot rolling plan optimization system was developed with the above hot rolling plan optimization algorithm as the core.The main functions include:contract data query and import,automatic scheduling by batch hot rolling schedule,Gantt chart display of hot rolling plan,scheduling results show of hot rolling plan,maintenance of benchmark data of hot rolling plan,etc.,which realized the automatic programming of the hot rolling plan and achieved good results.