Abstract: An apparatus for air-pulverizing high-temperature molten slag by blowing air at high speed through a nozzle into a flow of molten slag that is falling from an inclined container by the intermediary of a turndish. A heat detector is provided for detecting the quantity of heat in the flow of molten slag after being air-pulverized by the high speed air flow, and a feedback control device which is responsive to a detection signal issued from the detector is provided for calculating a desirable inclination angle of the container or the turndish and transmitting a control signal obtained as a result of the calculation to a controller for controlling the inclination of the container or turndish thereby stabilizing the air-pulverizing of the high-temperature molten slag.

Abstract: A process for desulfurizing molten steel comprising the steps of: removing converter slag from molten steel; adding a desulfurizing flux onto the molten steel from which the converter slag has been removed; supplying power to electrodes at a predetermined distance from the molten steel so as to generate an electric arc, the desulfurizing flux being melted by arc-heating so as to form the slag; and introducing a gas into the molten steel through a lance submerged into the molten steel to stir the molten steel and the slag which are arc-heated. In the process the desulfurizing flux is melted to a slag consisting essentially of 53 to 62% of CaO, 0 to 15% of SiO.sub.2, and 30 to 45% of Al.sub.2 O.sub.3.

Abstract: The object is to introduce a bottom-blown gas into a molten metal refining furnace so as to minimize the rate of blowing gas flow and increase the control range of the rate of blowing gas flow. There are included a refractory (1) having a plurality of holes (2) having an inner diameter of from 0.5 to 3.0 mm.phi. formed through said refractory and extending its working surface to its back, a metal cover (3) enclosing at least a part of the sides of the refractory (1) and a pressure box (4) formed in the bottom of the refractory (1) so as to communicate with the holes (2) and define a gas reservoir space. The molten metal is prevented from entering the holes (2) when the blowing gas pressure and the rate of blowing gas flow are decreased.

Abstract: A method for horizontal type continuous casting, which comprises: withdrawing a cast strand from a mold provided horizontally at the lower part of a tundish at a prescribed withdrawing speed for a prescribed period of withdrawing time; then, pushing back said cast strand for a prescribed period of pushback time in the direction opposite to the direction of withdrawal; and, withdrawing said cast strand again from said mold at said prescribed withdrawing speed for said prescribed period of withdrawing time; repeating said withdrawal and said pushing back, the distance of said withdrawal being longer than that of said pushing back; thereby intermittently withdrawing said cast strand from said mold; said method being characterized by comprising: limiting said prescribed withdrawing speed within the range of from 1.0 to 10.0 m/minute; limiting said prescribed period of withdrawing time within the range of from 0.05 to 1.5 second; and, limiting said prescribed period of pushback time within the range of from 0.

Abstract: A method for measuring the temperature of molten metal received in a vessel, which includes covering the tip portion of a probe which includes a thermocouple housed in an alumina protecting tube, from inside to outside with a ceramic fiber and a quartz glass; attaching the covered probe to the side wall of a vessel so that the tip portion of said probe projects into said vessel, at a position below the allowable lowest level of the molten metal received in said vessel; and maintaining the level of the molten metal at or above the allowable lowest level, thereby always immersing said probe into the molten metal received in said vessel.

Abstract: An apparatus for preventing a steam explosion, in a water discharge channel of a secondary cooling zone of a horizontal type continuous casting machine, caused by molten metal breaking out from said cast strand, which comprises: a metal net provided substantially horizontally between said secondary cooling zone and said water discharge channel for granulating said molten metal breaking out from said cast strand; a water flashing mechanism provided over the entire width of said water discharge channel above said water discharge channel, said water flashing mechanism comprising a plurality of water injection ports ejecting water on said molten metal granulated through said metal net for rapidly cooling and solidifying said molten metal and washing away the resultant soldified granulated metal toward the downstream of said water discharge channel; a tank, provided at the downstream end of said water discharge channel for receiving the water and the granulated metal discharged from said water discharge channel an

Abstract: In continuously casting steel, at least two pairs of reduction rolls are arranged near the crater top where the solidification of the molten steel in the cast strand is completed, said reduction rolls having a roll pitch of 200 to 420mm and giving a draft per pair of 0.1 to 2.0%, and said cast strand is reduced near the to of said crater, whereby the inner quality of said cast strand is remarkably improved.