Abstract: The invention relates to a furnace (1) for melting metal-bearing substances and/or production of liquid metal (4) of the type in which said metal (4) has above it a layer of slag (5) liable to be affected by a "foaming" phenomenon, in which a side wall of said furnace comprises an orifice (17) opening into an adjacent tank (22) capped with a vault (25), said tank (22) being capable of collecting a proportion of said slag (5) by overflowing through said orifice (17) when said foaming phenomenon takes on proportions that risk causing damage to said furnace (1).The invention also relates to a process for the production of liquid metal employing such a furnace.

Abstract: The device comprises an ultrasonic wave emitter (4) whose lower end portion (5) is immersed in the reactive solution (2) in which a sheet (3) to be pickled is immersed, and this end portion is provided with two emitting plates (6,7) respectively positioned on each side of an edge portion of the sheet (3) with their planar emitting surfaces parallel to the sheet and contained in two antinodal planes. Consequently, the two plates (6,7) vibrate in phase opposition and, if the vibratory amplitude is sufficiently large, these vibrations create a cavitation in the liquid in the space between the surfaces (3a,3b) of the edge portion and the plates (6,7) which considerably accelerates the rate of removal of scale from the edge portion.

Abstract: The device of the invention calibrates an apparatus for measuring the thickness profile of flat products, for example metal sheets, of the type which includes a source (10) of radiation, for example an X-ray source, and a row (20) of elementary detectors (21) which are aligned along the direction (P) of the profile to be measured and are placed on either side of a zone (2) for passage of said product. The device includes a set (32) of shims (33) having different radiation absorption characteristics, a carriage (30) for supporting the shims which is movable along the direction (P). For the calibration, the set of shims is moved in the passage zone so that each shim may intercept the radiation emitted by the source in the direction of each detector.

Abstract: The subject of the invention is a process of continuous coating, with a polymer deposition, of a metallic material in motion inside a chamber under a reduced pressure, in which process the monomer of the said polymer is injected, in the gaseous state, into the said chamber and the conditions for forming a cold plasma are created so as to cause coating of the said material with the said polymer deposition, which comprises, in at least one region of the said chamber, the said material being made to pass through a magnetic field so as to cause a variation in the composition of the said polymer deposition in the said region. The subject of the invention is also a device for the implementation of this process, and a product obtained thereby.

Abstract: One side of a metal strip forming a cathode is fed continuously at a given rate in an electrolyte past anodes supplied by respective controllable rectifiers. The strip is divided into increments of fixed length and predetermined width and coating rate. A total current for coating the increments is determined beforehand. The regulation method then includes determining the number of rectifiers to be put into operation, determining a predicted current for each rectifier by equally distributing the total current between said rectifiers to be put into operation, and determining current orders to be applied to the rectifiers to be put into operation. The method is cyclic for each side of the strip.

Abstract: The method comprises, at a given point of the production line:producing on the sheet a known localized deformation which is such that at least in a zone of a surface of the sheet the deformation is partially plastic;evaluating in the zone of the plastically deformed surface at least one surface stress.

Abstract: The subject of the present invention is a method for butt welding metal sheets (1, 2) by means of a laser beam, characterized in that a lateral pressure F directed towards the joint plane (3) of the metal sheets (1, 2) is exerted on the metal sheets (1, 2) to be welded in order that the contact pressure between the said metal sheets, at any point in the region of the joint plane (3), lies between 0.05 times the elastic limit of the metal sheet (1 or 2) having the lower elastic limit and the buckling pressure of the metal sheet (1 or 2) having the minimal buckling pressure and a welded seam is produced in the region of the joint plane (3) by local melting of the said metal sheets (1, 2) by means of the laser beam.The subject of the invention is also a welding device for implementing this method.

Abstract: A motor vehicle side panel which includes at least two uprights and a lower member of the substructure of the vehicle which form a door frame, and at least one door mounted upon the door frame which includes a solid lower part formed of an outer panel and an inner panel defining a housing for a drop glass therebetween. The inner panel is substantially planar and includes an inner side facing the door frame when the door is closed, with the inner panel including an outer side which faces the outer panel. Steel sections are welded on the inner side of the inner panel and project toward the door frame, with the steel sections extending at least along the portions of the inner panel which face the upright members and the lower member of the door frame.

Abstract: The subject of the invention is a method for butt welding at least two metal sheets of different thicknesses, by means of a laser beam. The method consists in bringing the metal sheets into contact at their lateral faces to be butt jointed, in directing the laser beam towards the thicker metal sheet so that the vertical axis X--X passing through the focal point P of the laser beam on the said metal sheet is at a defined distance from the joint plane of the metal sheets and in making a welded joint at the butt jointed lateral faces by local melting of the said metal sheets by means of a laser beam.

Abstract: The method for providing a temporary protection against corrosion of a cleaned metal product, in particular a metal sheet, comprises the following steps:applying on at least a part of the metal product an emulsion obtained by dispersion in water of 3 to 13% by volume of an oily phase comprising 75 to 90% by volume of at least one mineral oil, 5 to 10% by volume of at least one surface-active agent, and 5 to 15% by volume of at least one corrosion inhibitor,drying the coated metal product until a dry film is obtained.

Abstract: The subject of the invention is a device for simultaneous shearing of two sheet metal blanks comprising, for each sheet metal blank, an assembly formed, on the one hand, by a support member of the corresponding sheet metal blank comprising a rectilinear cutting edge and, on the other hand, by a movable cutter provided with a rectilinear cutting edge designed to interact with the cutting edge of the corresponding support member. The cutting edges of the two support members and cutters assemblies are situated in a same reference plane P and the support members extend on either side of the reference plane P. The invention applies to installations for welding by laser beam of two sheet metal blanks placed edge to edge.

Abstract: The process measures a characteristic (X) which is difficult to measure of a continuously produced product and comprises:choosing at least one easily measurable second characteristic (Y) whose variations are correlated to the variations of the first characteristic;modifying, by means acting on the product in a given zone of the production line, the first characteristic so as to put it into a known predetermined reference state (X.sub.o);taking at least in said zone a measurement of the second characteristic, and;processing said measurement for determining a variation in the first characteristic relative to the reference state (X).Application in the measurement of the flatness of a strip continuously travelling through a levelling machine.FIG. 2.

Abstract: The invention relates to a closed-loop regulating method for a metallurgical treatment carried out on a moving product (1), in which treatment the check measurement is obtained with a significant and variable delay in relation to the regulated treatment, in which method a digital regulator (14) having dynamic adjustment (RST sampled transfer-function) is used, characterized in that the sampling rate is continuously varied such that the abovementioned delay always remains equal to a predetermined integral number of sampling periods.

Abstract: The process is characterized by the fact that, before drawing, a salt of the alkaline metal group formed by Li, Na, and K, and of an anion which is chemically inert with regard to the essential metal of the sheet chose from among the phosphates is deposited on the drawing tools. To deposit the salt, preferably, a solution of said salt is applied to the tools or to the sheet metal.

Abstract: The invention provides a device for positioning sheet blanks (2, 3) in an installation for the continuous butt welding of the sheet blanks (2, 3) by means of a laser beam. The device comprises, on one hand, a conveyor table formed by an alternating arrangement of rails (11) having balls and bands (12) provided with projecting studs (13) evenly spaced apart and, on the other hand, friction means (15) adapted to be applied on the upper face of the sheet blanks (2, 3) and impart to the sheet blanks a movement in translation which is substantially perpendicular to the direction of feed of the sheet blanks (2, 3).

Abstract: A process for coating a steel strip, particularly ferritic stainless steel, with aluminum by hot quenching, in which the strip is preheated to a temperature less than 500.degree. C. in a first non-oxidizing atmosphere containing a quantity of oxygen less than 3%, the strip is then heated to a temperature less than 950.degree. C. in a second non-oxidizing atmosphere, the strip is then conveyed to an atmosphere (3, 4) which is non-reactive at the coating temperature, and, finally, the strip is quenched in a coating bath.

Abstract: Method for lining a distributor for the continuous casting of metals, in particular steel, comprising preparing material for constituting a wear-resistant refractory lining of the distributor with raw natural dolomite, or raw natural calcite, or a mixture of these two materials, which are chosen with a particle size of between 0 and 5 mm, incorporating in this raw material a binder in proportions of 0.4 to 5% by weight and a mineral or organic plasticizer in proportions of 0.2 to 3% by weight and, after the lining has been placed in position on the distributor in the aqueous form, proceeding to the decarbonation of this lining in the course of its drying and baking, characterized in that the method further comprises incorporating in the material of the lining at least one compound having the property of shrinking at temperatures lower than about 700.degree. C.

Abstract: Methods and device for the electric welding of at least two sheets of multilayer structure (2,5), termed sandwich sheets, each including at least two metal sheets interconnected by a film of polymer. The method includes putting the inner faces (3a, 7a) of the sandwich sheets (2,5) into contact in a partial overlapping region, applying on the opposite faces (4a, 6a) of the sandwich sheets at least two rollers each having two parts and placed in confronting relation to each other in alignment with the overlapping region, supplying electric power to at least the second part of each roller (9,10), exerting a clamping force on the overlapping region of the sandwich sheets (2,5) using the rollers so as to bring the second part of each of the rollers into contact with the inner face of the confronting sandwich sheet and shifting the rollers (9,10) along the overlapping region.

Abstract: According to this process, the strip runs through a bath of at least one electrolytic cell and two metal layers are successively deposited onto its surface by adjusting the current feeding the electrolytic cell so that the average value of the current density at the surface of the strip is less than a value called the limiting diffusion current of the ions of the metal to be deposited. In addition, during the formation of the first metal layer, the current is adjusted so as to prevent the appearance of localized overcurrents at the surface of the strip, it being possible for these overcurrents to exceed the limiting diffusion current. Such a process find particular application for electrogalvanizing.Application to an electrogalvanising process.

Abstract: Method for decarburisation of steel in a vacuum treatment chamber consisting of an upper part (4) in the shape of a bell, of an intermediate ring (5) and of a lower part (6) in which the bath of metal to be treated (2) is located and which is equipped with two legs (7, 8) which are immersed in the steel ladle (9) containing all the metal (10) to be treated, characterised in that oxygen is blown horizontally over the bath of metal to be treated (2), at the level of the intermediate ring (5), substantially at the centre of the latter.Vacuum steel-treatment chamber in which at least two horizontal tuyeres (11, 12) are provided in the intermediate ring (5) of the said chamber, substantially in the centre of the latter.