The Cold Rolling Daily Production Planning Orienting Logistics Balance

Iron and steel enterprise is a typical flow industry, with features of V-enterprise. Iron and steel logistics is characterized by multiple stages and multi-process, multi-unit, multi-line and complex logistics. Iron and steel production can be organized based on the order with the combination of "producing according to sales" and "producing according to demand" With consideration of the process, logistics, production organization characteristics, production management and production planning in iron and steel enterprises are extremely difficult. In face of the cold rolling stage which belongs to steel production finishing stage, this paper studies how to make high-quality production plans in order to meet the requirements of smoothing and balancing logistics, improving completion rate of orders and reducing cost of production.Cold rolling daily production plan orienting logistics balance problem includes determining capacity allocation plan in parallel cold rolling machine, determining the daily supplying quantity of each cold rolling machine to each of its subsequent cold rolling machine and determining the processing sequence of production order in cold rolling.The main works of this paper are listed as follows:(1) This paper proposes the two-stage hierarchical production planning strategy orienting logistics balance. The capacity allocation plan in parallel cold rolling machine and the daily supplying quantity of each cold rolling machine to each of its subsequent cold rolling machine are determined in the first stage, and the processing sequence of production order in cold rolling is determined in the second stage.(2) For the capacity allocation problem in the first stage, a mathematical programming model with nonlinear objective function is formulated then the objective function is linearized and then the problem is solved with CPLEX optimization software.(3) For the daily production planning problem in the second stage, the paper derives the constraints from the practical production. We develop a mathematical programming model. Then to solve the problem, a differential evolution algorithm is developed. Finally, the effectiveness of the algorithm is illustrated by data experiments.(4) Based on lots of investigation and research, we design and develop a daily production planning decision support system of cold rolling to meet the practical requirements of a large domestic steel company. This system can make daily production plan with the purpose of logistics balance, which has the above algorithm embedded it and adopts human-computer interaction manner.