Abstract: A melt and hold furnace includes a melt and hold chamber configured for containing a molten metal bath and having a tap for withdrawing molten metal and a preheat hearth disposed above a top surface of the molten metal bath. A sealed combustion chamber is disposed above the melt and hold chamber and is separated therefrom by radiation plates for radiating heat into the molten metal and hearth. Disposed in an operative relationship with the combustion chamber is a recouperative type burner for causing unimpeded circulation of hot combustion exhaust gases over the radiation plates from the burner and return to exhaust ports disposed within the burner. Conduits, passing through the combustion chamber and into the molten metal provides additional heating of the metal by heat conduction and the introduction of hot non-oxidizing gas into the metal.

Abstract: A stave cooling device includes a double drawn steel tube cast-mounted in a castable metal main body, and the double tube includes an inner tube which serves as a passage for a coolant. The inner tube of the double tube contains 0.20 to 0.38% of equivalent carbon and an outer tube of the double tube contains 0.15 to 0.25% of equivalent carbon. The outer tube has on its outer surface an alumina coating of 0.08 to 0.25 mm thick, and the main body is formed by casting a spheroidal graphite cast iron. The double tube is cast-mounted in the main body such that the double tube and the main body are not welded together.

Abstract: A process and apparatus for making steel in a basic oxygen furnace by the top-blowing of pure oxygen and the bottom-blowing of a gas mainly composed of carbon dioxide are disclosed, in which a waste gas discharged from said basic oxygen furnace is utilized as the only source of the gas to be blown into a molten metal.

Abstract: The present invention concerns a method of introducing refining gas and stirring gas into metal refining converters, and more particularly into converters in steelworks.To achieve this, the subject of the present invention is a method of blowing oxidizing gases, particularly pure oxygen, to refine metals, and more particularly to refine pig iron into steel, in a converter, by means on the one hand of a lance blowing from top to bottom, and on the other hand by protected tuyeres blowing, vertically or obliquely, from bottom to top, and characterized in that the amount of oxygen blown from bottom to top by the tuyeres is between 3% and 25% of the total amount of oxygen necessary to refine the metal bath, in that this oxygen is blown from bottom to top with a practically constant flow or a decreasing flow, i.e.

Abstract: A new fluxed pellet for use in iron-making is obtained by mixing and indurating about 1 to about 20%, by weight of the pellet, of ground melt shop slag fines with similarly ground iron ore concentrate, so as to achieve particular ranges of silica content, CaO/SiO.sub.2 ratio, and MgO content. The melt shop slag fines have been considered a waste material, but contain significant slag and metal values. The slag is already in calcined form for an energy saving as compared to the use of limestone and dolomite, and is already somewhat divided for a saving in grinding energy. The resultant basic pellets have better furnace properties than the acid pellet produced without slag addition.

Abstract: Slag is conditioned during blowing from above with oxygen of an iron melt by bubbling an inert gas into the melt from the bottom of the crucible in response to measurements made of the flowability of the slag layer and the speed of decarburization.

Abstract: An apparatus for supplying fluids to a converter has a rotary joint coupled to a trunnion shaft, one end of the rotary joint being connected to fluid supply pipes and the other end to fluid conduits communicating with tuyeres at the bottom of the converter. The rotary joint comprises a fixed casing and a rotary assembly, that is sealedly and rotatably fitted in the casing and connected to the trunnion shaft. The rotary assembly has a cylindrical member fitting in the casing. A plurality of axially spaced, circular communication grooves are provided in at least one of the internal surface of the casing and the external surface of the cylindrical member. The cylindrical member is provided with a passageway which opens into the communication grooves at one end and into the atmosphere where the cylindrical member emerges outside the casing at the other.

Abstract: The present invention provides a process for maintaining magnesium-containing cast iron melts in a castable state for comparatively long periods of time of, for example, several hours or days, with the use of a protective gas atmosphere, wherein the protective gas atmosphere present above the surface of the melt, as well as all the adjacent parts of the apparatus used, is kept at a temperature above the boiling point of magnesium, i.e. 1102.degree. C., and always has a partial pressure of magnesium vapor which is the same as or greater than the vapor pressure of the magnesium within the melt.

Abstract: A process is disclosed for the decarburization of a molten bath of chromium-containing pig iron which, in a single operation, permits decarburization by means of an oxygen jet and thus permits chromium or nickel chromium steels to be obtained directly, the decarburization of which can readily be completed by a final treatment under vacuum carried out immediately after the injection of oxygen. The process comprises adjusting the temperature conditions of the pig iron bath and regulating the oxygen jet distance from the surface of the bath and speed of oxygen gas so that the impact force of the oxygen creates a gas-metal emulsion within which the carbon contained in the pig iron is oxidized directly by the oxygen. The carbon content is thus rapidly reduced to less than 0.3% whereas the yield of chromium is higher than 97%. The process is suitable for the preparation of all grades of Cr and NiCr stainless steel, which optionally contain additions of Co, Mn or Mo.

Abstract: The invention provides an agent for desulfurizing crude iron and steel melts, the desulfurizing agent being based on calcium carbide containing calcium oxide. The desulfurizing agent is produced by admixing a calcium carbide melt having up to 45 weight % of calcium oxide therein with an excess of 3 to 15 weight %, based on the CaO-content of more than 45 up to 80 weight % desired for the final product, of calcium oxide. The resulting mixture is allowed to solidify and cool down to temperatures of 350.degree. to 450.degree. C. Next, the solidified melt is precrushed to material with a size of less than 150 mm. Particles with a size of less than 4 mm are screened off and the remaining material is comminuted, with the exclusion of moisture, to material with a size of less than 10 mm.

Abstract: Combination method for the gasification of coal and the reduction of metal ores involving hydrogenation gasification of coal to produce hydrocarbons and a coke component. The coke is subjected to steam gasification and the gas therefrom used to reduce ores. Spent gas from the reduction is treated to convert CO in the gas to H.sub.2 and CO.sub.2. The CO.sub.2 is scrubbed out and the H.sub.2 is sent to the hydrogenation gasification to hydrogenate the coal.

Abstract: A process for treating pig iron melts and steel melts or alloys in a converter, crucible or other vessel, wherein the entire refining and treatment process is carried out in a vessel with carbon dioxide, continuously and up to the finishing of the steel. Liquid carbon dioxide under a pressure of from 4.0 to 20.0 bar is used for the treatment. From about 50 to 300 kg of CO.sub.2 /tonne of steel are required for the refining of the pig iron melt.

Abstract: An industrial metallurgical delining assembly for dislodging and removing refractory or other material from upwardly open metallurgical process vessels. The assembly includes a spider-leg frame, the feet of which are supported on the upper periphery of the vessel, and supports a turntable over the top of the vessel. An extensible and articulatory boom depends from the turntable and selectively carries working tools at its free end for dislodging and removing material from the vessel. The vertical spacing between the uppermost end of the vessel and the turntable is sufficient to provide clearance for the boom to remove such dislodged material to a location outwardly from the vessel.

Abstract: A holder for an oxygen lance characterized by at least one actuating device comprising an operating lever which is connected to a shut off valve.

Abstract: Calcium or a calcium-bearing material is added to an aluminum-deoxidized steel in an amount which is sufficient to establish a calcium concentration exceeding the aluminum content by a value greater than about 0.14.

Abstract: Core flux composition of a flux-cored wire for welding and surfacing steels with a gas-shielded process contains the core flux ingredients in the following amounts, by weight %:______________________________________ rutile concentrate 20-40 fluorite concentrate 0.6-8.5 ferromanganese 13.5-18.5 ferrosilicon 1.6-2.7 nepheline concentrate 0.5-7 cryolite 0.6-4.

Abstract: Process and composition for desulfurizing pig iron in which the desulfurization agent consists essentially of calcium carbide, a gas-evolving component and fluorspar; the advantage of the process and composition is that it reduces dust pollution and danger of flaming in the handling of the slag after the desulfurization of pig iron.

Abstract: A process for the production of steel from a quantity of charge material such as iron scrap, iron sponge, or other essentially metallic iron carriers, makes use of a bottom-blowing converter. Nozzles are provided in the bottom area of the converter and extend into a sump. In order to avoid an uncontrolled flow without the addition of molten pig iron, a molten bath is formed of the charge material by the provision of burners located at the bottom wall area in a lateral wall above the nozzles, finally distributed carbon and oxygen being separately blown in through the nozzles for producing additional melting. The burners may be located either slightly above the level of the molten bath or below such level and in the latter case, the burners are then operated as additional nozzles after their submersion.

Abstract: Wall structure for a smelting stack is comprised of a cooling fluid flow pipe membrane layer comprised of a series of vertical, parallel arranged pipes extending between upper and lower manifold members. The pipe membrane completely surrounds a hot zone in the smelting stack. The upper and lower manifolds extend interiorly of the pipe wall membrane to define an alcove in which there is positioned a series of vertically arranged lengths of insulation cladding which are spaced from one another by gaps filled with fire-proof materials. The gaps contain elements of the pipe membrane layer directed interiorly of the pipe membrane. A waste-gas stack may be mounted directly adjacent the smelting stack with a common wall therebetween. The waste-gas stack wall comprises only a pipe membrane.

Abstract: A process for dephosphorization-denitrification of Cr-containing pig iron by oxidizing refining is disclosed. Said process comprises maintaining the C concentration of the molten metal at not less than 2%, contacting it with a slag comprising at least one of fluorides and chlorides of alkaline earth metals, at least one of oxides, hydroxides and carbonate of alkali metals, at least one of oxides of iron and nickel, while controlling oxidation of Cr.