Roller Matching And Batch Scheduling For Hot Rolling Production Of Seamless Steel Tube

Roller matching and batch scheduling are two important interrelated optimization problems in hot rolling process of seamless steel tube.The current research focuses on the batch scheduling problem of hot rolling,and the research on roller matching is not enough.In this paper,the roller matching problem is classified andits basic properties,basic algorithm and typical problems are studied.In addition,the comprehensive optimization of roller matching and hot rolling batch scheduling is studied.The main research contents and innovation are as follows:(1)According to the rules of roller matching under a given rolling batch sequence,the problem is divided into static roller matching and dynamic roller matching according to the rules of reuse of the roller during the rolling batch,and a mathematical model is formulated to comprehensively describe the two matching situations.For the static roller matching problem,the minimum turning quantity matching rule is proposed and the optimality of the rule is proved.For the matching of the dynamic roll pattern,it is proved that the dynamic roll matching effect is not inferior to the static roller matching under the minimum turning amount matching rule.Based on this,a basic heuristic algorithm based on the dynamic candidate roll set and the minimum turning amount criteria is proposed for the established mathematical model,which lays a foundation for considering hot roll batch sequencing of roller consumption.(2)A mathematical model was established for the hot-rolling batch scheduling problem that minimizes roller consumption.The effect of the rolling batch processing sequence on the roller consumption was analyzed,and the necessary and sufficient conditions for rolling batch reuse rollers in the same rolling batch were proved,and a lower bound of the problem under special conditions was given.On this basis,a two-stage heuristic algorithm based on optimal sequence matching and adjustment is designed to solve the problem.Simulation experiments based on actual production data show that the overall turning amount when rolling lot planning is implemented can be effectively reduced,and the production cost can be reduced.(3)Consider the problem of batch sorting where the rolled consumption is within a certain range,turn it into a batch sorting problem with batch priority and roller recovery constraints,and prove the NP-hard characteristics of the problem,analyzing the roller recovery time and batch processing.The relationship between time,put forward sorting rules for batch rationality.Because of NP-hard of the problem,a new variable neighborhood search algorithm based on batch rationality and operator performance was designed.The effectiveness of the algorithm is verified by simulation experiments.The study of this problem can provide batch sequencing schemes with different roller consumption thresholds.(4)A multi-objective mathematical model was established aiming at minimizing the roller consumption and tardiness penalties in hot rolling production for comprehensive optimization of roller matching and hot rolling batch sequencing.The relationship between batch consumption and roller production was analyzed.Considering the multi-objective and multi-constraint features of the problem,a multi-population evolutionary learning-based cultural gene algorithm was designed.For two different goals,different search operators and adaptive learning selection strategies were designed to guide population evolution to give full play to the global search and local search capabilities of cultural gene algorithms.Finally,the effectiveness of the algorithm is verified by simulation experiments.Researches on this issue can provide more comprehensive options for the batch sequencing problem.