SLAG COATING METHOD OF CONVERTER

PURPOSE:To prolong the furnace life and also to decrease the suspension time of a furnace and the consumption of a slag modifying agent or the like by coating the residual slag in a converter on the inside wall surface of the converter and thereafter cooling forcedly the above-mentioned coating layer. CONSTITUTION:After the tapping of a converter 3 executed with a refractory 2, a modifying agent such as dolomite is added to the residual slag 4 in the inside of the converter 3 and a slag coating layer 6 is formed on an inside wall surface 7 by blowing gas such as Ar and N2 into the converter from the tuyeres 5 and dissipating the slga 4. Thereafter a forced-cooling lance 9 which is provided with plural pieces of liquid spray nozzles 10a-10f to a tip part 8 of a cylindrical body is vertically hung in the converter 3 freely movably up and down and for example, water as liquid is fed to the lance 9 via a pressure-feed installation and the dissipation is performed through the tip part 8 to cool forcedly the slag coating layer 6. By such a method, the strengthened coating layer 6 can be formed and the wear of the refractory 2 is inhibited and the prolongation of the life of furnace body can be achieved.