9th ECCC European Continuous Casting Conference – ECCC 2017

The key technologies and development process for high speed casting technology were described by the study on the No.3 high-efficient slab caster of Shougang Jingtang Company. Within more than one year of technical research, some measures were applied to solve problems such as insufficient mold cooling, mold level fluctuation, and slab bulging. As a result, the casting speed successfully reached 2.5 m/min from 1.7 m/min for low carbon steel, and up to 2.0m/min for ultra-low carbon steel, with a slab section of 230×1650mm. In this paper, the characteristics of conventional slab mold heat transfer for high casting speed was also studied based on the practical historical data analysis, including mold cooling water temperate increment, the average heat flux and mold copper plate temperature variation. The mold average heat flux increased with the growth of casting speed, reaching nearly 2.05 MW • m-2 for wide face and 1.82 MW • m-2 for narrow face at a speed of 2.5 m/min. The minimum solidified shell thickness was above 12.3mm by model calculation. Also, a mathematical model for heat transfer and solidification in course of continuous casting slab was established to predict the solidified shell thickness at the mold exit. The shell thickness decrease with an increase in the casting speed, and the calculated thickness was about 12.3mm at a casting speed of 2.3 m/min. Through the in-depth study of the primary cooling process, it was beneficial to high speed continuous casting. The maximum casting speed reached 2.5m/min currently, and no breakout occurred during the high casting speed period.