A Study of Intermix in a Six-Strand Billet Caster

The purpose of this study was to develop an integrated intermix model suitable for a six-strand billet caster. Mathematical and physical simulations were performed in order to compare intermixing under the current procedure with alternative approaches. Plant data were collected, including different operational strategies regarding the tundish weight at holding level, to validate the findings. Additionally, samples were taken from the billets to understand the nature of strand mixing in small sections. The effect of tundish level during the holding procedure was evaluated. It was determined that the most pronounced effect on intermixing was caused by the difference in superheat between the old and new grades. The model will be used to reduce steel downgrade resulting from grade intermixing and for scheduling of intermix sequences.