Abstract: A method of manufacturing a heat resisting magnetic scale is disclosed which comprises a manufacturing process in which at least a part of a heat resisting base is heated and immediately cooled for the purpose of fusing the heated part to the base and changing both the magnetic characteristics of the part of the base which has been heated and the Curie point of the part which has been heated is raised to 100.degree. C. or higher.

Abstract: A method for controlling a flow rate of a liquid in particular of a molten material between a maximum flow and a zero flow, in a valve (1) comprising at least a fixed plate (2) and a mobile plate (3) which are superposed and maintained constantly in contact, each one having at least an opening (4, 5), said method, consisting of placing said openings (4, 5) more or less opposite each other by displacing said mobile plate (3) and wherein said mobile plate (3) is displaced according to at least two secant directions (6 and 7) which are determined for placing said openings (4, 5) of said fixed (2) and mobile plates (3) at least partly opposite each other when said valve is opened, and a valve for the application of said method.

Abstract: A flushing arrangement for a metallurgical vessel, in particular for a steelworks converter, includes a refractory lining constituting the working lining and pipes provided on predetermnined sites of the refractory lining, through which flush gas flows. In order to prevent the pipes from getting jammed and to obtain a strongly bundled gas jet, at least one bar-shaped insert extending in the longitudinal direction of the pipe is provided centrally in each pipe, forming an annular gap with the inner wall of the pipe.

Abstract: A continuous dip-plating apparatus for a steel strip has a pot containing a metal melt which forms a plating bath, a device for causing the steel strip to run through the plating bath such that the steel strip makes a turn around a sink roll in the plating bath so as to be pulled upwardly above the surface of the plating bath, and a wiping device disposed above the pot and adapted for adjusting the amount of deposition of the metal melt to the steel strip. The apparatus further has a pair of flow regulating plates for suppressing deposition of dross to the steel strip. The flow regulating plates are arranged in parallel with and in the vicinity of the portion of the steel strip running upwardly through the plating bath with the upper ends of the flow regulating plates being disposed substantially at the same level as the plating bath.

Abstract: Sealing apparatus of wind boxes at both the ore charge and discharge sides of a Dwight-Lloyd sintering machine provides a plurality of seal members disposed in series in close contact with the bottom surface of pallets of the sintering machine, and a seal chamber communicating with a space provided between these seal members. The seal members are rotatable rolls having seal plates projectingly installed radially on the outer periphery thereof, and may be rolls with these seal plates held in close contact with the bottom surface of the pallets and the inner surface of the seal chamber, or may be flat seal plates with their flat surface firmly pressed against the bottom surface of the pallets. In the seal chamber is mounted an independent exhaust fan for the removal of air, further improving sealing performance.

Abstract: A refractory plate unit for use as a sliding plate or as a stationary plate in a sliding closure unit at an opening of a metallurgical vessel includes a refractory plate having therethrough a discharge opening. A metal member is rigidly attached to the refractory plate and has an annular surface centered radially outwardly of the discharge opening and mating with substantially no free play with a complementary surface of a metal frame supporting the refractory plate unit.

Abstract: An electro-magnetic nozzle device for controlling the jet of liquid metal tapped at the outlet of a melting crucible comprises an electro-magnetic inductor and a magnetic field concentrator which surrounds the outlet of the crucible and is constituted by at least four three-dimensional sectors arranged evenly around the crucible outlet and separated from each other by radial slits, each sector having an internal water-cooled cavity, radially inner and outer walls of which the inner wall is of less height than the outer wall, and windings disposed in the inner and outer walls forming an electro-magnetic inductor.

Abstract: An endothermic furnace for sintering metal includes a pair of U-shaped retort tubes which are mounted to the underside of a flat, rectangular lid, the lid being removably secured along the respective top vertical edges of the furnace chamber sidewalls and the retorts being removable with the lid. Each tube carries a catalyst and receives a carbonaceous gas mixture that is either combusted externally or internally of the chamber, the gas reacting with the catalyst to produce a desired endothermic gas product which heats each tube whereby to radiantly heat the chamber and which is piped back into the heat chamber, when cooled, to provide an oxygen-free atmosphere for the heat treating chamber.

Abstract: Disclosed are wearable carbon-containing refractory elements, such as wearable refractory parts of a slide valve for use in controlling flow of molten metal from a metallurgical vessel, which are impregnated with tar or other wear reducing agent. In order to prevent decarburization of the refractory elements, they are saturated in an aqueous borate solution and then dried, so that the borate will migrate outwardly toward the surfaces of the elements and form protective layers which will prevent infiltration of ambient air into the refractory material. Prior to saturation of the elements in the borate solution, the wearable surfaces of the elements, such as those surfaces which will be subject to contact with molten metal, are coated with film which will prevent saturation by the borate solution, such that no protective layer is formed at the wearable surfaces. This allows the tar or other wear reducing agent to migrate outwardly through the wearable surfaces so as to reduce wear caused by the molten metal.

Abstract: A tundish impact pad is provided for use in a tundish vessel. The impact pad has a wavy upper surface which significantly reduces the horizontal surface area in the region of impact where molten iron or steel enters the tundish vessel. This wavy surface substantially reduces the vertical splashing of molten iron or steel entering the vessel, causing a significant reduction in agitation and turbulence within the vessel. The impact pad may exist as a discrete structure or may form an integral part of the structure of the tundish vessel.

Abstract: Apparatus for the opto-electronic control of a flame cutting machine having photoelectric sensors of different spectral sensitivity. The sensors may be positioned within a cutting torch and directed during operation on a flame and a workpiece to be cut. The sensors are connected at their outputs with computing means to generate control signals for the advancing movement of the cutting torch relative to the workpiece. In order to reduce the impact of disturbing variables on the control signals, an electronic means for generating the quotient of the sensor output signals is connected with the outputs of at least two of said sensors. The quotient of the output magnitude of the sensors is used to control the flame cutting machine.

Abstract: The torch fitted with a nozzle (6) comprises a visual observation optical device having one end part coaxially inside the central gas feed pipe (7) and the other end extending outside the body (1) at the opposite end to the nozzle; the optical device being situated a specific distance from the main orifice (17) of the nozzle so that the bounds of its angle of view pass through the edges of said main orifice.

Abstract: Disclosed is a tundish apparatus for holding and filtering molten metal, such as steel, prior to the molten metal being continuously cast. An enclosure around the discharge orifice of the tundish accommodates a ceramic filter medium. The enclosure has a removable cover plate to allow continuous discharge of the molten metal in the event the filter medium becomes clogged and to allow access to the tundish nozzle.

Abstract: There is disclosed a plant for treating and melting metals, metal compounds and/or metal alloys or for producing calcium carbide. It includes a burden-receiving shaft and a melting furnace arranged below the shaft and including a heating means. A passage opening is provided between the shaft and the melting furnace, which passage opening serves to introduce the burden present within the shaft into the melting furnace.In order to be able to introduce the hot burden into the melting furnace without difficulties and without operational failures due to charging means, a gas-permeable supporting plate rigidly arranged on the melting furnace is provided at the passage opening, corresponding to at least the shaft cross section by its cross section. A clearance is provided beside the supporting plate. The shaft is designed as a structural unit separate from the melting furnace. The shaft and the melting furnace are relatively movable with respect to each other in the direction of the clearance and back.

Abstract: A blast furnace tap hole drill is provided having an elongated feedshell which supports a percussion drill, drill rod assembly, and a centralizing drill rod support disposed between the percussion drill and a stationary forward end drill rod support, and a drive means for advancing the percussion drill and centralizing drill rod support in unison along the length of the feedshell such that the advancing motion of the centralizing drill rod support ceases as it nears the forward drill rod support without stopping the advancing motion of the percussion drill.

Abstract: Electric arc oven for melting scrap iron of the type comprising a vat lined with an inner coating made of refractory material which is called the sole of the oven, lateral walls, a vault capping the upper opening of the vat, openings provided in the vault through which the electrodes extend, and a tapping nozzle or eccentric tapping hole. In this oven, the sole is provided with at least one device for injecting gas to stir the molten metal. The injection device includes a low injector formed of a compact block made of dense non-porous refractory material through which extend one or a plurality of, preferably less than 50, hollow metallic tubes or slits or channels along its entire height in the direction of gaseous blowing and permitting gas to pass therethrough.

Abstract: An apparatus for a smelting reduction of iron ore comprising a preheat and prereduction furnace which preheats and prereduces iron ore, a smelting reduction furance into which said preheated and prereduced iron ore, carbonaceous material and fluxes are charged and in which said preheated and prereduced iron ore are smelted and reduced, a top blow oxygen lance having decarburizing nozzles and post-combustion nozzles and blowing oxygen into said smelting reduction furance, and at least one side tuyere placed at a side wall of the smelting reduction furnace and at least one bottom tuyere placed at a bottom of the smelting reduction furnace through which a stirring gas is respectively blown so that at least a part of said stirring gas introduced through said at least one side tuyere hits a swollen portion of the molten metal by said stirring gas introduced through said at least one bottom tuyere.

Abstract: Ladle covers are insulated with refractory ceramic fiber modules. An outer portion of a lower part of the cover conforming to the shape of the ladle rim is insulated with trapezoidal modules. A central portion beneath the cover within the outer portion is insulated with rectangular modules, which may be of less thickness than the trapezoidal modules.

Abstract: This invention provides an apparatus for automatically connecting a gas supply to a vessel employed to contain molten metal whereby gas, such as argon, is injected into the molten metal in a selected interior portion of the vessel, such as a ladle.The ladle is positioned on a tilting structure so that it can be tipped to flow out slag on the top on the molten metal, the slag and other impurities in the metal being directed to the top thereof by the upwardly flowing argon gas.The apparatus comprising an upstanding male connection mounted on the tilting structure so as to be engageable in a downwardly facing female connection mounted on the ladle. The connections are shaped to insure a substantially gas tight connection whereby gas in a desired volume at a desired pressure are introduced into the ladle.

Abstract: An annealing treatment in a continuous furnace in which a flow of dense inert gas is injected in a rising duct and a descending duct, these flows being regulated by the analysis of hydrogen detected by a pressure controller acting on valves to achieve a minimum escape of hydrogen.