Design And Implementation Of Production Planning And Job Scheduling Method For Cold Rolling Line

The cold rolled sheet enterprises of iron and steel industry has the characteristics of multi-device, multi-process and parallel, and its production process is relatively complex. The production of cold rolled sheet enterprises has to consider two main problems to adapt to the demand of small quantities and varieties of production of market. First, the production continuity must be guaranteed; second, the custom demand must be satisfied such as the variety, specification, number and date of delivery. Therefore, it is necessary to study the problem of order planning and operation scheduling and develop a production scheduling system for the cold rolling line.In this paper, taking the production practice of a cold rolling sheet plant in Shanghai Baosteel as a background, the requirement of the order planning and operation scheduling problem of the whole cold rolling process is considered. Firstly, a whole optimization model which aims at the order planning and scheduling is proposed. Secondly, this model is divided into two sub-models and solved respectively. The optimization objective of the model is to minimize the sum of order delivery delay punishment and campaign size violation and switching virtual cost. Then, a novel reasoning algorithm based on time window and the artificial intelligent algorithm are developed to solve the corresponding planning and scheduling sub-model, respectively. Finally, a simulation is given to verify the effectiveness of the model, and its related algorithm by using the actual data from the cold rolling sheet plant is implemented.For the practical demand, a sub-system for the order planning and job scheduling of the whole cold rolling process is developed based on the .NET platform and the B/S structure. The proposed algorithm is encoded by C sharp and the FLEX technique is employed to enhance the flexibility of human-machine coordination. The system has been running in the Shanghai Baosteel Co., Ltd., which can realize the whole order planning and scheduling function, play an important guidance for the production scheduling of each unit in the cold rolling line. The purpose of increasing production efficiency, improving planning precision and alleviating scheduling complexity of manual work has been also achieved.