Abstract: An apparatus is disclosed for producing metal powder having a molten metal holding vessel with a generally cylindrical shaped bottom portion, a molten metal discharging runner located at the bottom portion of the holding vessel, a spraying chamber connected at a lower end of the discharging runner, a first induction heating coil having a diameter and surrounding the holding vessel, a second induction heating coil surrounding the discharging runner, and a ring-shaped magnetic shielding plate disposed between the second induction heating coil and the sliding gate. The discharging runner has a nozzle portion which includes a sliding gate made of ceramic. The sliding gate is movable for controlling the flow of the molten metal through the nozzle portion of the discharging runner. The spraying chamber has gas-jetting nozzles. The second induction heating coil has a diameter smaller than a diameter of the first induction heating coil.

Abstract: Disclosed are an improved method of refining steel and an apparatus for practicing the method.The refining method comprises, basically, carrying out the refining, particularly, decarburization, while stirring molten steel in the refining furnace by injecting gas thereinto, while supplying heat with a burner installed at the top of the furnace to the molten steel. According to this method, it is possible to start at an initial carbon content of the moltend steel lower than that of known AOD process, and complete the refining in a curtailed period of time and with a decreased oxidation loss of Cr. Thus, damage of refractory materials of the furnace is reduced, and the amount of Si necessary for reducing Cr-oxides in the latter stage of the refining is also reduced.Oxygen for the decarburization is supplied usually in the form of gas, but can be supplied from a solid oxygen source.

Abstract: A method of melting iron scrap using an arc furnace with reduced electric power consumption.In one of a pair of vessels which are arc furnace bodies, melting of the scrap by heat of arc is carried out while a carbonaceous material and oxygen-containing gas are introduced therein to cause oxidation of C to CO to make use of the oxidation heat. Thus formed hot exhaust gas containing CO is introduced to the other vessel of the pair and oxygen-containing gas is added thereto to cause oxidation of CO to CO.sub.2 thereby heating the scrap loaded in the vessel. Melting is further continued by changing the roles of the two vessels to each other.Generation of the CO-containing hot gas can be performed in a separately installed gasification furnace.