Automatic Control of Slag Line for Submerged Entry Nozzle (SEN)

Abstract

This paper describes an automatic control method for the slag line for SEN during continuous casting of steel, which is an improved even erosion method based on adjusting the immersion depth of SEN with appropriate time intervals. It aims to extend the service life of SEN. This automatic control method has been applied to an actual billet continuous casting machine, and the results of field trials show that the average service life of SEN improved significantly. In addition, the average erosion rate decreased from 0.053 mm/min to about 0.04 mm/min. The effects of the immersion depth of SEN on fluctuation of the molten steel surface and power consumption are discussed. The results indicate that the fluctuation of the molten steel surface and power consumption both decreased as the immersion depth of SEN increased.