Abstract: With respect to a radiant tube burner to be used for heating a heating furnace or the like, to suppress the generation of NOx accompanying combustion, to make the structure thereof fit for a radiant tube burner equipment, to simplify the control of a fuel supply system and an air supply system, and to prevent the coking. Furthermore, to provide a combustion control scheme appropriate to a radiant tube burner. For these purposes, the present invention placed the respective tips of a fuel nozzle, e.g., pilot burner joint-use nozzle (11), and an air throat (13) in the end of a radiant tube (3) and moreover has a combustion air injection port (33) of the air throat (13) provided to be deviated in contact with or near to the inner circumferential wall surface of the radiant tube (3). In addition, a control device (307) for making a burner burn alternately.

Abstract: A combustion burner comprises: an air supply passage for supplying an air to a heating furnace; a primary fuel nozzle for supplying a primary fuel to the air supply passage; secondary fuel nozzles arranged around the air supply port of the air supply passage; and the secondary fuel nozzles being arranged so that a distance L (mm) from an outer periphery of the air supply port to the outer periphery of the secondary fuel supply port is larger than the diameter Da (mm) of the air supply port. A combustion method comprises: injecting fuel substantially from the primary fuel nozzle when an infurnace temperature of the heating furnace is lower than a fuel ignition temperature; and injecting fuel substantially from the secondary fuel nozzle when an infurnace temperature of the heating furnace is higher than a fuel ignition temperature.

Abstract: Methods of manufacturing a composite ferrite of two or more of metal oxides prepared from a chloride solution containing ions of these metals, one of the metals being zinc. The methods comprise (a) ejecting a high temperature gas to the solution or atomizing the solution and (b) supplying the atomized gas to a combustion gas containing oxygen, to evaporate moisture from mist particles of the solution in a short period of time so that the zinc chloride in the solution is not substantially evaporated and to induce a heat decomposition or chemical reaction for the remaining metal salt particles, thereby forming a composite ferrite.

Abstract: A method for controlling coating weight on a hot-dipped steel strip comprises the steps of positioning at least one pair of high-frequency (alternating) current conducting paths near one side of a steel strip and near another side of the steel strip drawn out of a coating bath, each of the high-frequency (alternating) current conducting paths being parallel with a surface of the steel strip above the coating bath, and flowing a-high-frequency (alternating) current strong enough to magnetically saturate the steel strip through the at least one pair of high-frequency (alternating) current conducting paths to induce a high-frequency (alternating) current of an opposite phase in the steel strip, a magnetic pressure acting on surfaces of the steel strip being generated by an interaction of the induced high-frequency (alternating) current with a high-frequency (alternating) current of the high-frequency (alternating) current conducting paths.

Abstract: A method for continuous casting of steel comprises the steps of feeding molten steel to cooling device for cooling molten steel by use of feeding device for feeding molten steel; cooling fed molten steel by the cooling device; generating a high-frequency magnetic field near a zone where the feeding device, the cooling device and molten steel contact each other; and converging the high-frequency magnetic field on the zone where the feeding device, the cooling device and molten steel contact each other. Further, an apparatus for continuous casting of steel comprises feeding device for feeding molten steel; cooling device for cooling molten steel fed by the feeding device; generating device for generating a high-frequency magnetic field near a zone where the feeding device, the cooling device and molten steel contact each other; and converging device for converging the magnetic field on the zone where the feeding device, the cooling device and molten steel contact each other.

Abstract: Molten metal is put under pressure of up to 10 atmospheres in a covered ladle and a gas soluble in the metal is bubbled through the melt. Some gas goes into solution, while the remainder rises in bubbles and brings inclusions suspended in the molten metal up to the surface. Then the pressure is lowered, after which gas comes out of the solution in fine bubbles which also bring impurity inclusions up to the surface. In another method molten steel is refined at pressures not exceeding atmospheric pressure in a covered ladle equipped for evacuation and equipped for bubbling gas through the molten steel bath. Bubbling followed by pressure reduction can then be performed to form two stages of cleaning. Heat may be added for compensating the cooling effect of gas expansion.

Abstract: A burner for directly flaming steel making materials to accomplish reduction without oxidation, wherein the burner comprises a plurality of combusion air outlets spaced circumferentially of the inner wall of a tubular burner tile, and fuel gas outlets disposed centrally of the burner tile, and wherein the combustion air outlets and fuel gas outlets are formed and disposed with specified jetting angles and distances to produce burning without oxidation.

Abstract: A burner for directly flaming steel making materials to accomplish reduction without oxidation, wherein the burner comprises a plurality of combustion air outlets spaced circumferentially of the inner wall of a tubular burner tile, and fuel gas outlets disposed centrally of the burner tile, and wherein the combustion air outlets and fuel gas outlets are formed and disposed with specified jetting angles and distances to produce buring without oxidation.

Abstract: An inventive method may perform a plating the surface of the metals sheet without using a molten plating metal. This method successively melts a supplied solidus plating metal in close proximity of the passing metal sheet and adheres the molten plating metal as a plating film to the surface of the metal sheet, where the metal sheet passes upwardly and the plating metal is supplied through an upwardly-directed nozzle disposed near the passing sheet, and when or immediately before the plating metal is supplied from the nozzle, it is molten by a heat melting means. The molten plating metal forms a pool at a corner defined between the surface of the passing sheet and the tip of the nozzle, and the molten metal of the pool forms a plating adheres to the sheet surface and forms the plating film.

Abstract: A burner for directly flaming steel making materials to accomplish reduction without oxidation, wherein the burner comprises a plurality of combustion air outlets spaced circumferentially of the inner wall of a tubular burner tile, and fuel gas outlets disposed centrally of the burner tile, and wherein the combustion air outlets and fuel gas outlets are formed and disposed with specified jetting angles and distances to produce burning without oxidation.

Abstract: A burner for directly flaming steel making materials to accomplish reduction without oxidation, wherein the burner comprises a plurality of combustion air outlets spaced circumferentially of the inner wall of a tubular burner tile, and fuel gas outlets disposed centrally of the burner tile, and wherein the combustion air outlets and fuel gas outlets are formed and disposed with specified jetting angles and distances to produce burning without oxidation.

Abstract: A burner for directly flaming steel making materials to accomplish reduction without oxidation, wherein the burner comprises a plurality of combustion air outlets spaced circumferentially of the inner wall of a tubular burner tile, and fuel gas outlets disposed centrally of the burner tile, and wherein the combustion air outlets and fuel gas outlets are formed and disposed with specified jetting angles and distances to produce burning without oxidation.

Abstract: A burner for directly flaming steel making materials to accomplish reduction without oxidation, wherein the burner comprises a plurality of combustion air outlets spaced circumferentially of the inner wall of a tubular burner tile, and fuel gas outlets disposed centrally of the burner tile, and wherein the combustion air outlets and fuel gas outlets are formed and disposed with specified jetting angles and distances to produce burning without oxidation.

Abstract: A method and an apparatus, wherein heat can be effectively transferred to molten metal contained in a reaction vessel. The pressure of the gaseous atmosphere within the vessel is maintained higher than atmospheric pressure. Oxygen gas is blown to a layer of molten slag contained in the vessel through tuyeres set in the reaction vessel, thereby to achieve post-combustion therein. The pressure in the vessel is controlled within the range of 2.0 to 5.0 kg/cm.sup.2 by a pressure regulator.

Abstract: A steel ingot having a still-liquid portion therein is charged into a soaking pit; then, said ingot is heated by injecting a fuel from a combustion unit of said soaking pit into said soaking pit with a constant and minimum fuel flow rate capable of holding a pit temperature higher by from 10 to 100.degree. C than the cold point temperature of said ingot at the completion of solidification of said still-liquid portion in said ingot, until said still-liquid portion in said ingot is completely solidified; and then, upon the completion of said solidification, the surface portions of said ingot are further heated up to above a prescribed temperature permitting rolling thereof by injecting a fuel from said combustion unit into said soaking pit with a constant fuel flow rate of at least 60% of the maximum fuel flow rate of said combustion unit, thereby reducing the fuel consumption in said soaking pit.

Abstract: In an evaporative cooling method by natural circulation of cooling water by the use of an evaporative cooling device comprising a cooling pipe fitted to an object to be cooled and a steam separator drum arranged above said cooling pipe, said cooling pipe and said steam separator drum being connected together by a downcomer and a riser, the cooling water in said cooling pipe is kept in complete liquid state and part of cooling water is evaporated only in said riser and said steam separator drum by setting parameters to satisfy the following formula:Q/V.sup.. .rho..sup.. c<.DELTA.T.sub.eq (P.sub.o, Ph.sub.3)WhereQ : Thermal load acting on said cooling pipeV : Amount of circulated cooling water in said cooling pipe.rho. : Lensity of cooling waterc : Specific heat of cooling waterP.sub.o : Pressure of said steam separator drumPh.sub.3 : Pressure of cooling water in the uppermost part of said cooling pipe.DELTA.T.sub.eq (P.sub.o, Ph.sub.3) : Boiling equilibrium temperature difference between P.sub.o and Ph.sub.