Abstract: A repairing material for the bricks of the carbonizing chamber in a coke oven is obtained by compounding mortar as a main component with a powder comprising 70-100 wt. % of a Co compound, Ni compound, and/or Al compound and 0-30 wt. % of at least one compound selected from among the compounds of Ca, Mg, Zn, Sr, Ba, Fe, V, Pb, Cu, and Ti, and a liquid formed of water, B, P, and at least one member selected from among Si, Na, and K. A method for repairing includes hot applying the repairing material to portions of the bricks of the carbonizing chamber in the coke oven which are in need of repair.

Abstract: When casting castable refractories as lining refractories of a ladle for a molten metal, wherein the castable refractories are prepared by kneading monolithic refractories with an aqueous solution of a binder containing alumina cement, the castable refractories are preheated on the basis of the open air temperature and cured after casting while keeping the temperature thereof within a set temperature range of from about 20.degree. C. to 40.degree. C. The method stabilizes the hardening time of castable refractories and forms cast refractories excellent in strength and erosion resistance.

Abstract: The present invention has been devised to obtain a metallurgical effect by introducing refining gas into a molten metal in a metallurgical vessel and stirring the molten metal sufficiently by convection, and to improve durability of one nozzle or a few nozzles for introducing the refining gas. At a predetermined position of a furnace bottom onto which a ramming mass is provided, a few cylindrical refractory sleeves are disposed close to the upper face of the furnace bottom from the lower portion thereof. In each cylindrical refractory sleeve a gas introducing nozzle, which introduces the refining gas, is disposed in such a manner that it can be drawn out downwardly for replacement.