Abstract: The variation of manganese during BOF smelting was studied, the factors and the variation rules of end-point manganese content of liquid steel were analyzed. In view of actual production data in 220 t converter, the process route and operation methods for stably producing the steel containing manganese with the mass fraction of less than 0.10 % were obtained. By optimizing the gun position and carbon pulling time during the converter blowing process, controlling the endpoint oxidation and temperature of the converter, adopting a slag retention dual slag mode, and controlling the manganese content of the molten iron and scrap steel, as well as the amount of slag discharged from the steelmaking process, the residual manganese at the endpoint of the converter steelmaking is less than 0.07 %, which can meet the composition requirements of low manganese steel.

Key words: converter, low manganese steel, residual manganese content, end-point control