Research On Production-Logistics Of Heavy Plate Mill Based On The Theory Of Constrains

With the increasing competitions in market, the requirement on enterprises’production from the society is becoming more rigorous. This includes: (1) Quality requirement turns higher; (2)The delivering time is shorter;(3) The production cost for resources such as labour force and energy goes higher. So the living space of steelmaking enterprises shrinks. As a kind of steelmaking enterprises, which products can be used in many different fields, the Heavy Plate Mill focus on multiple-production and small batches in production organizing. In the conditions of producing to orders, it is necessary to increase production capacity and reduce the delivery time by optimizing production logistics management for the Heavy Plate Mills.Three problems are studied in this paper which will be faced to apply TOC in the production logistics management: (1) How to identify and analyse the bottlenecks;(2)How to set buffers;(3) How to do production planning and control. Based on instance of the Heavy Plate Mill , it is put forward that to compare the capacity of passing through plate in every production process to identify and analyse the bottlenecks. When producing some typical products , the process that needs more time to finish its task will be the bottleneck. For setting the buffers, it is brought forward that to compute the size of middle storage by statistic data for capacity difference and states of equipments from different producing lines. During producing planning, the capacity of bottleneck should be considered firstly, pulling producing model should be used in the processes before the bottleneck and pushing producing model should be used in opposition. The production management should focus on releasing the bottlenecks by applying different methods such as tackling key problems and setting buffers to protect the capacity of bottlenecks to pass through plate, and upgrade the efficiency and capacity of producing. So the goal to attain more profit can be reached by accelerating the production speed and shortening the production delivery period.By applying TOC in production management, the Heavy Plate Mill of Baosteel has attained success. The production capacity has been enlarged, the production delivery time has been reduced and the production efficiency has been improved.