Abstract: An electrically heated valve element for sliding type valve joints in the outlet of a molten metal vessel has an electrical heating conductor disposed predominately in the outlet closing surface section of the valve element so that when moved to the casting position where the molten metal flow passage aligns with the flow passage from the vessel, the outlet closing surface of the element is maintained at a uniformly high temperature so that any cooling down of the outlet closing surface is avoided. The valve element is made by embedding the heating conductor which is air annealed nichrome wire in spiral form, into the refractory material of the valve element by vibration, the embedding mass being free of organic substances, carbon, sulfur, metallic iron, alkalies and/or electrically conductive substances.

Abstract: There is disclosed a process for the production of a ceramic heat-retaining brick based on olivine which comprises shaping and drying a mixture of granular material and a binding agent. The granular material includes powdered iron having a particle size of less than 0.1 mm in an amount of between 5 and 20% by weight of the brick. The brick is subsequently burnt in an oxidizing atmosphere and the powdered iron is substantially converted to iron oxide.

Abstract: A ceramic burner for the combustion chamber of air heaters and the like has a mixing body composed of layers of shaped ceramic bricks, the shaped bricks adjoin each other with radial flanks and engage and mutually interlock with one another by knobs or protuberances and corresponding recesses. The layers of shaped bricks are held together vertically by a ceramic bolding bar. In assembly, the mixing body has a mushroom shape wherein the upper layer shaped bricks have a larger radius than the lower layers.

Abstract: A refractory brickwork wall having an opening therethrough has incorporated therein, at a position above the opening, a relief brickwork configuration in the form of a gable or roof. The relief brickwork includes a plurality of relief bricks each having an upper inclined surface, a lower inclined surface and a lower, generally horizontal step surface. The relief bricks are arranged one above the other in an inclined formation with the lower inclined surface of the upper relief brick of each pair of adjacent relief bricks resting on the upper inclined surface of the lower relief brick of such pair of adjacent relief bricks, and with the upper relief brick of each pair of adjacent relief bricks being partially offset in a horizontal direction from the lower relief brick of such pair of adjacent relief bricks.

Abstract: A regenerative heater includes a regenerator container having open opposite ends. The container contains therein a fill of heat retaining material which is permeable to the passage therethrough of gas, throughout the entire length thereof in opposite directions between the open opposite ends of the container. The fill of heat retaining material comprises solid fine granular particles having a low thermal conductivity. A heat source is positioned adjacent the first end of the fill of heat retaining material. At least one blower is provided for circulating gas in opposite directions through the entire length of the fill of heat retaining material and across substantially the entire cross-section thereof. A charging flow of gas is first circulated in a first direction through the fill of heat retaining material, such that the charging flow of gas is heated by the heat source and then passes through the heat retaining material while transferring heat to the heat retaining material.

Abstract: There is disclosed a frame for a sliding gate, which in use holds the movable and fixed plates against each other under pressure and which is formed of refractory concrete reinforced with metal elements which are screened from the molten metal by the refractory concrete.

Abstract: There is disclosed a sliding plate for a three plate sliding gate nozzle apparatus comprising a refractory concrete body with metal reinforcement embedded in it and extending out of at least one end a drive connection integral with or engaging the reinforcement whereby the usual external metal frame used to support the plate can be dispensed with.

Abstract: Parts subject to wear, which come into contact with metal melts, are formed with a hydraulically setting high-alumina refractory concrete having a compression strength when cold, measured on dried crude product, of at least 400 kp/cm.sup.2. The compression strength is at least 700 kp/cm.sup.2 after firing at 1400.degree. C. The refractory concrete has a dimensional stability at 1400.degree. C. of at least plus or minus 0.2%. The refractory concrete contains corundum and active alumina as aggregates, an alumina concrete containing less than 22% lime and, as required, a thinning agent. Up to 5% of the aggregates can be replaced by a spinel-forming substance preferably MgO or MgO-yielding compounds; or up to 5% of the aggregates can be replaced by carbon black, pitch or graphite; or up to 7% of the aggregates can be replaced by chromium oxide. Aggregates under 0.5 mm can be present in the refractory concrete as round grains.

Abstract: A block of refractory material has extending therethrough a throughflow opening, preferably including a funnel-shaped inlet converging inwardly to a throughflow duct. An annular gas collecting space is provided within the block at a position surrounding the throughflow opening radially outwardly thereof. A gas feed duct extends through the block from the exterior thereof to the gas collecting space. At least one annular duct extends radially inwardly from the gas collecting space to the throughflow opening. The annular duct opens into and forms with the throughflow opening at least one narrow slit which extends around the entire periphery of the throughflow opening.

Abstract: Materials suitable for lining vessels designed to hold molten iron or steel are provided herein. These materials are made of burned dolomite, containing 1-6% of a natural glyceride oil or a mixture of such oils and 2-6% by weight of a dry inorganic particulate bonding agent, such as potassium silicate or phosphate.

Abstract: A wear part for sliding gates used for the outlet of vessels which contain metal melts therein, the wear part being for example a sliding plate, a base plate, an inlet tube or an outlet tube. The wear part includes a refractory material surrounded by a metal mantle, where a fireproof refractory concrete is poured into a mold and hardened therein so that the mold serves as the metal mantle when the concrete has hardened. A lining surrounding a through-bore in the wear part may be cast therewith. The wear part is preferably clamped in a supporting frame.

Abstract: A burner includes a central burner duct for passing combustion gas therethrough and an outer annular duct for the passage of combustion air and coaxial to the central burner duct. The ducts open or join at an opening area, upstream of which are one or two areas where the combustion gas and air are combined or brought together and mixed. A disk-shaped mixing element is positioned within the opening area centrally thereof and downstream of the first combination area and adjacent the second combination area. The mixing element has extending therethrough substantially in the direction of flow, a ring of separate passages.

Abstract: A refractory bottom lining has extending therethrough at least one inclined decarburization or refining nozzle or tuyere. Surrounding the nozzle is an outer perforate brick having a hole therethrough. An inner brick fits within the hole of the outer brick and has a bore which is inclined at the same angle of inclination as the nozzle. The nozzle extends through the bore.

Abstract: A hot-blast furnace of the type including an outer metal casing and an inner lining of insulating and refractory material has therebetween a layer of foamed glass or foamed silicate material having a structure of closed pores or small cells which are closed in an air tight manner to each other. The layer prevents passage of gas, during operation of the furnace, to the inner surface of the outer metal casing.

Abstract: A shaft casing has a funnel-shaped widened upper portion connected to a cupola casing. Between the widened portion and a refractory shaft lining is a supporting frame having a platform on which a cupola lining rests. The frame is connected to the lower end of the widened portion.