Required. During converter steelmaking, the alkalinity of the slag is high, and the MgO content in the slag reaches or exceeds the saturation value. After the furnace is tapped, the furnace temperature decreases, and some high melting point substances (MgO, C2S, C3S) precipitate, and the slag viscosity increases. When the slag is splashed, Except for part of the slag that is bonded to the furnace wall and lining, most of it remains at the bottom of the furnace and combines with the periclase crystals of magnesia carbon bricks at the bottom of the furnace, causing the furnace bottom to rise. When the furnace bottom rises, the reaction space in the furnace becomes smaller. , the dephosphorization effect becomes worse, and it is easy to cause splashing, which increases steelmaking costs and brings safety risks, affecting the smooth flow of converter production, so furnace cleaning is required.