Rules-based systems for improved monitoring and guidance of reheating furnaces

The aim of the project has been the development and implementation of intelligent monitoring and guide control systems for optimised reheating furnaces operation, based on artificial intelligence techniques, in terms of: component and process diagnosis; estimation of the temperature and furnace atmosphere set points. Two different industrial applications have been considered: the ThyssenKrupp Steel AG hot strip mill in Bochum/Germany, where the re-heating process monitoring system has been realised; the furnace 301 at the SSAB Tunnplat hot strip mill in Borlaänge/Sweden, where a component and process online monitoring/diagnostic system has been developed. The systems are able not only to prevent or to diagnose malfunctions in the furnace, but also to monitor the reheating process according to different production range, providing the operator with guidance when deviating from correct behaviour. The two installed rules-based systems are actually in operation. The results from the industrial testing of the systems are good. New rules in the furnace operation guiding system can be easily integrated. This results in a higher acceptance of the computer based furnace control system by the furnace operator. The switch-on time of the furnace control system increases and the good results for the temperature control using the computer based system is expanded. Energy consumption and quality results can be enhanced. The furnace monitoring based on the automatic application of the rules to the huge quantity of data collected in the database allows to keep the furnace operative conditions under control.