Abstract
Štore Steel Ltd. faces a huge problem with ladle nozzle opening during the production of a wide variety of steel grades. After the ladle treatment the steel melt is poured from the ladle through the sliding gate and the nozzle into the tundish on the continuous casting machine. Due to often cloggings the ladle nozzle must be opened with the oxygen which can cause melt pollution. The purpose of this paper is to present the attempt for reducing ladle nozzle openings. In this attempt genetic programming method was used. The experimental data on 115 consequently cast heats was used. The steelmaking technology number, batch sequence number, time spent for secondary metallurgy, sustainability of upper nozzle brick, sustainability of nozzle seating block, sustainability of lower nozzle brick, ladle number, sustainability of the ladle, foreman of the secondary metallurgy and melt chemical composition (Al, C, Mn and Si) were taken into account for the prediction of ladle nozzle opening. The best genetically developed model for ladle nozzle opening prediction correctly predicts 107 out of 115 situations of opening the ladle. The results of the genetic programming based modeling have been used in practice for the changing of several steelmaking technologies.