MUD MATERIAL FOR BLAST FURNACE TAP HOLE

摘要

PROBLEM TO BE SOLVED: To obtain a mud material for a blast furnace tap hole which is inexpensive and has particularly excellent strength and corrosion resistance in a high-temp. region by forming the mud material in such a manner that the bending strength at the high temp. attains the specified value or above. SOLUTION: The mud material having the bending strength of >=25kg/cm<2> in a temp. range of 1450 to 1550 deg.C is obtd. by compounding roasted anthracite and/or pitch coke powder and alumina powder, mixing ceramic powder therewith at need and maintaining the total value of alkaline components (Na2 Owt.%+K2 Owt.%) at <=0.5wt.% with tar as a binder. The corrosion resistance to molten iron and molten slag is improved and the tapping time is made >=4 times heretofore by using such mud material. The saving of materials for casting hearth work and the manpower saving for the preliminary work for the furnace is attained and the safer operation of the blast furnace is made possible.