Abstract: Disclosed is a method of continuous casting of aluminum-killed steel, using a refractory martial containing 20 mass % or more of CaO.MgO-based clinker. 60% or more of MgO grains included in the grains of the CaO.MgO-based clinker have a diameter of 50 ?m or less. The refractory martial is used at least at a portion to be in contact with molten steel. The present invention can reduce the diameter of MgO grains as inclusions in slabs to suppress the occurrence of flaws in a milled sheet metal.

Abstract: A casting nozzle joint structure capable of easily positioning and jointing a nozzle without any holder for fixing and supporting a continuous casting nozzle therethrough. The joint structure comprises fitting mechanism formed in and on the mating faces of the continuous casting nozzle and the pressure clamper. The fitting mechanism includes a convex portion and a concave portion formed in and on the mating faces of the continuous casting nozzle and the pressure clamper so that they fit one another. The concave or convex portion formed in the mating face of the continuous casting nozzle is fitted on or in the convex or concave portion formed in the mating face of the pressure clamper, and this pressure clamper clamps the fitted engagement. Thus, the nozzles can have their outlet bores positioned, and the submerged entry shroud can have its discharge port oriented.

Abstract: A process is disclosed for making a casting nozzle wherein gas can be blown out through the outlet of the nozzle to prevent the sticking of nonmetallic impurities to the nozzle during use. Reticulate organic filaments in the form, e.g., of a net are applied around a preformed inner cylindrical refractory body having a pouring hole therein. An outer cylinder body is then formed around the inner cylinder body including the organic filaments. The entire body is then fired, whereby the organic filaments carbonize and evaporate, leaving a network of gas-permeable reticulate holes in the body. An outlet is drilled or cut in the fired body through the gas-permeable holes to the pouring holes. Accordingly, when the nozzle is in use, a blowing gas can be provided through the reticulate holes to the nozzle outlet to prevent the sticking of nonmetallic impurities.

Abstract: A casting nozzle designed such that the sticking of nonmetallic impurities to the outlet of the nozzle is prevented by blowing out a gas. The casting nozzle comprises a nozzle proper, an annular hollow chamber for gas blowing formed in the axial direction of the nozzle proper, and annularly arranged reticulate small holes for gas blowing communicating with the annular hollow chamber, the small holes opening at the outlet of the nozzle. The reticulate small holes are formed when organic filaments wound round a portion of the inside wall of the nozzle proper carbonize, volatilize, or shrink upon heating.

Abstract: A gas-blow casting nozzle has an annular gas-blowing hollow chamber with a gas-permeable part which is provided between the hollow chamber and the pouring hole of the nozzle body, and a number of joint parts for integrally joining the inner wall and the outer wall of the hollow chamber, which are provided in the radial direction of the annular hollow chamber. The total of the vertical section of the cylindrical area of the joint parts is about 30% to 70% of the cylindrical area of the hollow chamber. The gas-blowing hollow chamber which has the function of a heat-insulating layer is so constructed that the inner wall and the outer wall of the hollow chamber are partially and uniformly joined with the joint parts, and the joint parts are made to have the function of a heat-transfering layer, whereby the temperature difference in the radial direction of the nozzle body may be made small and the occurrence of thermal stress in the casting nozzle may be prevented.