Abstract: A structure of the oxygen passage in a steel converter supporting trunnion comprises a hollow chamber provided where a trunnion shaft projects from a trunnion ring. In the hollow chamber is inserted a hermetic manifold, to which a horizontal pipe communicating with a rotary joint and a vertical pipe communicating with an oxygen tuyere in the bottom of the converter vessel are welded. Inside the manifold, there is fitted a communicating member containing a bend-like passage through which the horizontal and vertical pipes communicate with each other.

Abstract: A method for smelting charge materials in an electric arc furnace consists in that a bath of the electric arc furnace is loaded with the charge materials, electrodes of the electric arc furnace are supplied with an alternating current, the charge materials are melted, redox reactions are conducted and a finished melt and a slag are tapped, the alternating current of industrial frequency supplied to the electrodes of the electric arc furnace being first converted to one of a frequency ranging between 0.05 and 30 Hz. An apparatus for carrying into effect the above method comprises an electric arc furnace, in a bath of which are inserted electrodes. A secondary winding of a transformer is coupled with the electrodes through power supply arrangements.

Abstract: In bottom blown oxygen steel making or in top and bottom blown combined oxygen steel making, a tip end of a tuyer immersed in molten steel is seriously damaged or melted away due to very high temperatures due to the vigorous combustion of carbon, manganese and so on by the oxygen blown into a furnace.In order to prevent such damage, hydrocarbon gas has been blown through space between an outer pipe and an inner pipe of a dual pipe tuyere or tuyeres, but such hydrocarbon gas rather excessively lowers the temperature of the molten metal adjacent to the tip end of the tuyere and often blocks the opening of the tuyere.Now, instead of blowing in hydrocarbon gas, particulate material such as limestone magnesite, dolomite and the mixture thereof are proposed to be blown into the molten metal in the decarburization steel making vessel carried by an innert gas, combustion gas, blast furnace gas, LD process gas and oxygen or a mixture of these gases.

Abstract: A lance for use in a basic oxygen vessel is provided with a fluid cooling arrangement which is mounted directly on the lance structure and which is vertically adjustable therewith to provide a fluid spray which effectively enables and ensures cooling and suppression of the exiting gas before it contacts the hood and moves into the ducts of the hood structure.

Abstract: A method of making a nonmagnetic, austenitic, manganese-chromium-nickel-nitrogen stainless steel uses intermediate addition of ferroalloys and novel mixtures of oxygen and nitrogen to maintain the temperature of the melt below about 3150.degree. F. (1732.degree. C.). The method improves on the economics of making specialty steels by reducing the cost of raw materials and refractories.

Abstract: A converter vessel is coaxially surrounded by a trunnion ring carried by a pair of trunnions for rotary or tilting motion about a horizontal axis. In order to permit rotation of the vessel relative to the trunnion ring about the vessel axis at right angles with the noted horizontal axis, two annular rows of support elements such as rollers are mounted on the trunnion ring and engaged with respective annular tires on the vessel so as to bear its radial load. Two other annular rows of rollers or like support elements are also mounted on the trunnion ring and engaged with the respective tires so as to bear the axial vessel load. Several identical drive mechanisms are compactly mounted within the trunnion ring for revolving the vessel through a gear drive, friction drive, or chain drive.

Abstract: Tuyere for the processing of metals in the liquid, solid or pasty state, and capable of introducing simultaneously and separately a gas and a powdered material. The tuyere comprises at least two well-centered concentric tubes, the gas being introduced into a non-external tube, and the powdered and compressed material being introduced into another tube, which is lubricated on its inner wall by a film of a lubricating substance introduced through a slot formed therein. The outer tube is traversed by an agent protecting the tuyere against its hot wear.

Abstract: A porous plug for treating molten metal is characterized by a porous refractory body having an axis and a wear detection refractory element in transaxial juxtaposition with the porous refractory body over a portion of the axial height of the body, the wear detection refractory element having an emissive power different from that of the porous refractory body to provide a discernible indication of the extent of wear of the porous refractory body. The wear detection refractory element may be in the form of a porous refractory insert internally located within the porous refractory body or a non-porous refractory sleeve surrounding the porous refractory body, or combinations thereof.

Abstract: A magnesium ferrosilicon alloy for in-mold nodulization of ductile iron consisting of 5-15%, by weight of magnesium, 60-80% silicon, 0.1-1.5% calcium, 0.1-3.0% aluminum, 0-2.5% rare earth, and balance iron.

Abstract: A copper or copper alloy ingot is forged or rolled into a plate; blind bores are deep-drilled into the plate from one of its narrow edges and plugged; inlet and outlet nipples for the ducts are provided on the rear surface; and the front surface of the plate is provided with grooves or short sleeves for holding a fireproof lining structure or material.

Abstract: A process for periodically and pneumatically stirring a bath of molten metal, wherein during the periods in which no stirring effect is required a fluid in gaseous state is injected through injection devices below the surface of the bath of molten metal in an amount sufficient to prevent blockage of the devices, whereas during the periods in which a stirring effect is required a fluid in liquid state which will vaporize quickly upon contact with the liquid metal is injected to provide an optimum amount of mixing gas with a minimum of injection devices.The process is advantageously used in converters for pneumatically converting pig iron into steel and in which oxygen is blown from above onto the bath of molten metal.

Abstract: A method for improving surface defect of specific steel resistant to concentrated nitric acid, wherein the specific steel in a molten state, either a stainless steel comprising C.ltoreq.0.1 wt %, 2.5.ltoreq.Si.ltoreq.5 wt %, Mn.ltoreq.2 wt %,15.ltoreq.Cr.ltoreq.20 wt %, 10.ltoreq.Ni.ltoreq.22 wt %,C.times.10.ltoreq. at least one of Nb, Ta and Zr.ltoreq.2.5 wt %,the balance being iron and inevitable impurities,or a high-silicon-nickel-chromium steel comprisingC.ltoreq.0.03 wt %, 5.ltoreq.Si.ltoreq.7 wt %, Mn.ltoreq.10 wt %,7.ltoreq.Cr.ltoreq.16 wt %, 10.ltoreq.Ni.ltoreq.19 wt %,C.times.4.ltoreq. at least one of Nb, Ta and Zr.ltoreq.2 wt %,the balance being iron and inevitable impurities,is admixed with titanium (0.05.ltoreq.Ti.ltoreq.0.2 wt %) when producing said steel.

Abstract: For continuously reducing and melting metal oxides and, respectively, metallic materials pre-reduced to a large extent, fuels are completely burned within a melting receptacle. The melting receptacle (8) is tightly passing at its upper side into at least one supply space (7) essentially extending in horizontal direction. The effluent gases of the complete combustion within the melting receptacle (8), are emerging via the supply space (7), coal dust being supplied via a coal dust nozzle (15) to the hot combustion gases immediately prior to entering the supply space (7). The hot combustion gases essentially consisting of CO.sub.2 and H.sub.2 O are at least partially converted to CO and H.sub.2 and cooled and are passed with a temperature exceeding 800.degree. C. within the supply space (7) in countercurrent to the charge material (10) to be supplied into the melting receptacle (8). While passing through the charge material (10), the combustion gases supplied with a temperature exceeding 800.degree. C.

Abstract: A bath of liquid steel containing metallic impurities is subjected to vacuum effective to cause emission from the bath surface of the metallic impurities as a bulk flow of rising gases. The surface of the bath is kept substantially free of surface contamination. The rising gases are disposed of to prevent reflux. The pressure is then returned to normal, and the treated steel recovered. Preferably, the chamber pressure is maintained at a level equivalent to 60% to 80% of the total vapor pressure of the liquid metal. Desirably, the liquid steel is lifted (for example, by using a gas), from a lower level in the bath to at least its surface to enhance circulation within the bath. Preferably the rising gases are condensed remote from the bath surface to prevent reflux.

Abstract: A refractory gas permeable structural unit for blowing a gas into a metal treatment container and through its casing, has a refractory gas permeable stone, a first metal housing sealingly surrounding the stone, a second metal housing arranged at a distance from the first metal housing, a refractory substantially gas impermeable filler material provided between the first and second metal housings, and at least one connection and a distribution chamber provided at the end face of the stone.

Abstract: An inoculating alloy for addition to molten cast iron is disclosed. The composition is a silicon ferro alloy containing five to eight percent calcium as its active ingredient.

Abstract: An apparatus for equalizing the pressure in shaft furnaces which are operated at a pressure in excess of atmospheric pressure. At least one storage bin is connected to the furnace chamber, although isolated from the atmosphere and the furnace chamber by sealing valves. A gas pipeline serves to selectively supply or exhaust gas to the storage bin to equalize pressure. In one embodiment of the invention, two storage bins are interconnected by a gas pipeline and appropriate valves for equalizing pressure between the storage bins.

Abstract: Very significant improvements in the hot workability of an age hardenable nickel base alloy containing 17 to 20 percent chromium, 2.9 to 5.3 percent titanium, 1.8 to 2.8 percent aluminum, 11 to 15.5 cobalt, 2.5 to 7 percent molybdenum, 0.8 to 1.5 percent tungsten, 0.004 to 0.040 percent boron, 0.02 to 0.06 percent carbon and about 52 to about 57 percent nickel are achieved by melting the raw materials under vacuum in the presence of lime, and forming a desulfurizing lime slag on the surface of the molten raw materials, and thereafter adding magnesium thereto just prior to casting the alloy, preferably while maintaining the molten raw material under an inert gas atmosphere.

Abstract: A method for induction melting wherein the formation of high melting temperature refractory oxides formed by the reaction of one or more of the raw materials being melted with oxygen is avoided by the introduction of boron.

Abstract: Ferrovanadium carbide addition agents comprising 75 to 85% vanadium, 8 to 12% carbon, 8 to 12% iron, less than 2% oxygen and having a density of from about 5.8 to about 6.2. The addition agents are produced by fusing vanadium oxide, iron and carbon at about 1700.degree. C. to about 2100.degree. C.