A model to predict coil temperature evolution during the whole thermal cycle process of ladle with a novel steel teeming technology

Electromagnetic induction controlled automated steel teeming (EICAST) is a ladle-sand-free technology applied to the steel teeming process for clean steel practice. The temperature of the induction coil in the EICAST system greatly influence its service life. In this paper, a numerical model was developed to predict the temperature evolution of the induction coil without or with a nano thermal insulation felt (WDS) during the whole thermal cycle of ladle. Industrial experiment was conducted for the model validation. The results indicate that WDS reduces the coil temperature at the ladle baking and secondary refining stages, however it causes a rapid jump in the coil temperature from 309°C to 707°C during the induction heating process. Because the coil temperature is high enough compared to its ambient temperature after the induction heating stage, the temperature of the induction coil using WDS heat insulation material drops to 461°C constantly at the steel teeming stage. The measured temperatures of the nozzle brick and coil in the industrial experiment correspond well with the calculated ones by numerical simulation. The developed model could be used to predict the coil temperature evolution and improve coil cooling strategy at each stage of the whole thermal cycle process of ladle for the industrial application.