Abstract: In the baking of carbon anodes (for aluminum reduction cells) or the like, in so-called ring-type furnaces where green carbon bodies are deposited in pits, each of which is circumstanced successively for preheating stages, one or more baking stages, and cooling stages, while air travels in heat exchange relation through flues past a series of pits respectively undergoing such cooling, baking and preheating operations, improvement is effected by introducing water spray into the air as it flows past the pits at a cooling region. Such water, first as spray and then as vapor, increases the quantity of heat that can be absorbed by the air flow and also increases the heat transfer coefficients of the flue walls in the cooling regions, so as to provide recovery or removal of heat in greater amount or more rapidly.

Abstract: In a process for the electrocoloring of anodized aluminium in which colors are obtained by interference effects the pores of an anodic oxide film, produced by D.C. anodizing in sulphuric acid, are enlarged by electrolytic treatment in an acid electrolyte having a high dissolving power for aluminium oxide under alternating current conditions.

Abstract: A process for the production of aluminium in two steps:2Al.sub.2 O.sub.3 +9C=Al.sub.4 C.sub.3 +6CO (ii)andAl.sub.4 C.sub.3 +Al.sub.2 O.sub.3 =6Al+3CO (iii)Reaction (ii) takes place in a materials addition chamber and reaction (iii) in a high temperature chamber. Slag is circulated between the chambers via conduits by the action of gas generated in reaction (iii) in the conduits. Aluminium production in the high temperature chamber and slag circulation rate are independently controllable by the provision of independent heat sources.

Abstract: For the clearance of anode effects in operation of electrolytic cells for aluminium production, movement in the metal pool is induced to effect short-circuiting of the cell and disturbance of any gas film on the face of the anode(s) by raising the anode(s) and then lowering them to datum position and/or tilting the anode in relation to datum position. Upward movement is terminated either after a predetermined distance or when a predetermined cell voltage is attained. Fresh alumina is introduced into the cell by breaking alumina crust by anode movement or by independent supply.

Abstract: In a process for production of aluminium metal carbon monoxide gas evolved at very high temperature through reaction of aluminium carbide and alumina is cooled by contact with a molten alumina slag at a lower temperature to cause back reaction of contained aluminium suboxide and Al vapor and consequent heat transfer to the contacted molten alumina slag.

Abstract: A continuous length of aluminum is anodized during passage through an anodizing electrolyte and then colored during passage through an inorganic coloring electrolyte, in which a counterelectrode is immersed. In the electrolytic coloring stage alternating current with a superimposed D.C. compound is preferably passed between the anodized aluminum and the counterelectrode when the electrolyte is appropriate for such treatment. The alternating current circuit for the electrolytic coloring stage is preferably completed via an electrode immersed in the anodizing electrolyte at a position facing substantially unanodized aluminum so as to effect a liquid contact.

Abstract: A process for the production of aluminium in two steps:2Al.sub.2 O.sub.3 +9C=Al.sub.4 C.sub.3 +6CO (ii)andAl.sub.4 C.sub.3 +Al.sub.2 O.sub.3 =6Al+3CO (iii)Reaction (ii) takes place in a materials addition chamber and reaction (iii) in a high temperature chamber. Slag is circulated between the chambers via conduits and is promoted by gas supplied from an external supply. Chamber heating may be by electrical resistance between chamber electrodes and the gas may be introduced via one or more hollow electrodes.

Abstract: A process for the production of aluminium in two steps:2Al.sub.2 O.sub.3 +9C=Al.sub.4 C.sub.3 +6CO (ii)andAl.sub.4 C.sub.3 +Al.sub.2 O.sub.3 =6Al+3CO (iii)Reaction (ii) takes place in a materials addition chamber and reaction (iii) in a high temperature chamber. Slag is circulated between the chambers via conduits and electrical resistance heating is carried out in the conduits. Heating is controlled by differential control of the resistance of the slag in the conduits by the application of gas to at least one of the conduits.

Abstract: In a process for production of aluminium metal described in U.S. Pat. No. 4,099,959 carbon monoxide gas is evolved at very high temperature through reaction of aluminium carbide and alumina in a high temperature zone of the system. This gas is cooled by contact with a molten alumina slag at a lower temperature to cause back reaction of contained aluminium suboxide and Al vapor and consequent heat transfer to the contacted molten alumina slag.A body of molten alumina slag is maintained in a pretreatment zone, to which carbon and alumina feed are introduced and the carbon monoxide gas is led into the pretreatment zone. Excess slag, resulting from such introduction of feed and from gaseous back reaction, spills over into a low temperature zone of the system to augment the circulating slag stream.

Abstract: Aluminium and other non-ferrous metals are continuously cast in the form of a thin strip in a thickness range of 5-30 mm through an open-ended casting mould. The emerging strip is cooled in conventional manner by direct application of coolant as it emerges from the mould. The novel feature is that the solidified strip is gripped at its side edges at a station close to the exit of the mould and positively pulled out of the mould.

Abstract: In a apparatus for the production of aluminium a molten alumina slag, containing combined carbon is circulated through one or more alternately arranged relatively low temperature zones where carbon is added to increase the combined carbon content of the slag by reaction with the alumina slag and high temperature zones where aluminium metal is released by reaction of aluminium carbide and alumina in the slag with consequent depletion of the combined carbon content. Alumina is supplied to the slag at one or more locations. The energy to drive the reactions is preferably supplied by resistance heating of the slag particularly in transit from a low temperature zone to a high temperature zone although usually additional energy is supplied to the slag in the return from a high temperature zone to the next low temperature zone.In most instances the aluminium-liberating reaction is carried out in an upwardly inclined passage and the gas evolved is employed to achieve the circulatory movement of the slag.

Abstract: A new aluminum grain, together with a process for its preparation, suitable for use in blasting agents is described. The grain, obtained by shearing sheet material of various types with a modified cutter comprises largely flat particles with jagged edges, and contains minimal quantities both of oversize and undersize particles.

Abstract: An electrolytic reduction cell for the production of aluminium has current collector bars running across the floor of the cell unitarily or in separate sections. Deformation of the molten metal/electrolytic bath interface is reduced by leading current out of the collector bars or bar sections at positions remote from their ends by connector bars connected to said positions.

Abstract: In the continuous casting of metal in strip form between moving belts while maintaining a flowing layer of liquid coolant between the reverse surface of a belt and mutually adjacent, guiding-surface, nozzle elements that deliver such coolant, such elements are each constituted as a cooling and guiding unit having a hexagonal face and including releasable retaining elements normally holding such face (through which coolant is projected against the belt) at desired level under spring pressure against the engaged elements. The elements, respectively with the hexagonal head and with a fixed support, are disengaged by depressing the head and turning it, thus allowing removal of the device for replacement or service. As the hexagonal heads can be arranged very closely together, except for narrow, liquid-withdrawal spaces between adjacent edges, practically complete support for a coolant layer across and along the entirety of the belt, is attainable, yet with practicality of construction of the units.

Abstract: A method of and apparatus for producing a container or the like by deep-drawing a flat blank of a sheetlike aluminium material. The blank is deep-drawn by means of a first drawing stroke into a cylindrical container blank and brought into its final shape by means of a counter drawing stroke, whereby the inner wall and outer wall of the cylindrical container maintain their positions. The apparatus comprises two telescoping dies with oppositely directed working strokes, between which dies there is arranged at least one drawing ledge.

Abstract: For supporting and cooling the reverse surfaces of belts in apparatus for continuously casting metal strip between such belts, means enclosing the reverse surface of a belt includes a multiplicity of guiding faces that are distributed closely both crosswise and lengthwise of the belt to define an intended belt path, and that have nozzle openings through which liquid coolant is projected against the belt, rapidly flowing out in a layer over the guiding face and being withdrawn at localities close to all of the guiding faces. The belt, which may be forced toward the faces to stabilize it in its desired path, thus rests on a layer of rapidly moving liquid coolant, which affords efficient heat removal and an essentially complete liquid bearing, such apparatus and procedure being also deemed applicable to cooling other surfaces.

Abstract: In a process in which strip metal is subjected to heating while suspended as a catenary in a heating zone, the strip is passed into the heating zone in a condition in which the lower surface is slightly elongated in relation to the upper surface. The differential elongation may be due to "coil set" in the strip feed coil or may be applied by a roller leveller or equivalent mechanism during passage from a feed coil to the heating zone. The procedure is conveniently employed to control edge creep and improve flatness in stoving coated strip or in annealing operations.

Abstract: An on-line particle size analyzer which is able to take measurements on material flowing along a line in real time and thus enable automatic process controls to be effected. The apparatus periodically takes a sample of material, dilutes it to a predetermined concentration in a turbidimeter, and then passes it to one of a number of vertical sedimentation cells in which a particle size analysis is carried out. Each sedimentation cell is formed simply as an enlarged part of a line passing from the turbidimeter around a loop back to the turbidimeter and, in order to fill the respective sedimentation cell, the sample is pumped round the loop until steady-state conditions have been reached, whereupon the flow is stopped and measurements begun. When the measurements, which are carried out by optical means, are completed, the whole loop, including the sedimentation cell is automatically flushed out.

Abstract: In the scrubbing of gases containing sorbable contaminants, particularly the waste gases from reduction cells for electrolytic production of aluminium the waste gas is injected tangentially into the bottom of a cylindrical chamber, from which it is withdrawn through an axial outlet passage at the top end. A solid sorbent material is introduced into the chamber at one or more positions at the top end of the chamber in such a way that it enters the ascending gas stream in a peripheral zone of the chamber.

Abstract: In a process for electroplating aluminum articles, the article is first electrolytically treated, as anode, in a bath consisting essentially of a solution of caustic alkali, and thereafter electroplated. The electrolytic caustic cleaning step, preferably involving agitation, is found specially suitable in composition and indeed is effective in a relatively short time to afford an essentially bare aluminum surface, i.e., free of anodic oxide film and also free of pitting or smut, for advantage in plating, as with tin or other metal. Intermediate steps can be employed such as immersion tinning or zincating and brief electroplating such as a bronze strike; the electrolytic cleaning co-acts well with the intermediate stages, indeed requiring fewer steps over all. Although applicable batchwise, the process is particularly appropriate for continuous electroplating wherein the aluminum wire or strip may pass rapidly through the electrolytic cleaning, intermediate and plating baths in succession.