Abstract: A method introducing a stirring gas through a vessel bottom, receiving a measurable mechanical vibration by at least one sensor fixed to the vessel or to a supporting frame thereof, filtering the thus detected vibration signals by a high pass filter and preferably by a low pass filter, sampling and digitizing the vibration signals for exposing them to a second filtering which is digital and calibrated upon the vessel vibration responses, sequencing the response, exposing each sequence to the calculation of a temporal moving mean square, and extracting the total effective value RMS (Root Mean Square) of the measured vibration signal therefrom. The effective value is used for controlling the stirring gas flowrate supplied to the vessel. The method can be used for a stirring stand of steel making shop ladles, converters, RH processes, electric arc furnaces, etc.

Abstract: A device for control of bubbling of a metal bath in a ladle or in another similar metallurgical vessel including a bottom injector linked to a source of supply of pressurized stirring gas to be injected with aid of a pipe provided with a facility for adjusting flow rate, at least one vibration sensor mounted on the vessel itself or on a support frame, a signal processing unit processing a vibratory signal gathered by the sensor, and wherein the signal processing unit includes at least, and in successive order of processing of the vibratory signal, a high-pass analog filter, a digitizer, a digital filter calibrated on vibratory responses of the ladle, and a computer for computing a sliding temporal quadratic mean of RMS type.

Abstract: A device for control of bubbling of a metal bath in a ladle or in another similar metallurgical vessel including a bottom injector linked to a source of supply of pressurized stirring gas to be injected with aid of a pipe provided with a facility for adjusting flow rate, at least one vibration sensor mounted on the vessel itself or on a support frame, a signal processing unit processing a vibratory signal gathered by the sensor, and wherein the signal processing unit includes at least, and in successive order of processing of the vibratory signal, a high-pass analog filter, a digitizer, a digital filter calibrated on vibratory responses of the ladle, and a computer for computing a sliding temporal quadratic mean of RMS type.

Abstract: The inventive method consists in introducing a stirring gas through the vessel (1) bottom, in receiving a measurable mechanical vibration by at least one sensor fixed to the vessel or to the supporting frame thereof, in filtering the thus detected vibration signals by a high pass filter (13a) and preferably by a low pass filter (13b), in sampling and digitising (15) said vibration signals for exposing them to a second filtering which is digital and calibrated upon the vessel vibration responses, in sequencing said responses, in exposing each sequence to the calculation (17) of a temporal moving mean square, in extracting the total effective value RMS (for ‘Root Mean Square’) of the measured vibration signal therefrom, wherein said effective value is used for controlling the stirring gas flowrate supplied to the vessel. Said invention can be used for the stirring stand of steel making shop ladles, converters, RH processes, electric arc furnaces, etc.

Abstract: The invention concerns a method which consists in injecting into a molten metal bath to be treated, jointly but separately into the same bath zone, oxygen and carbon in a form capable of being blown (powder carbon preferably) so as to generate locally in the bath CO bubbles from those two elements, which will then be loaded in denitriding nitrogen. A stoichiometric adjustment of the carbon and oxygen inputs enable a constant carbon denitriding in the bath. The method is preferably applicable to the production of low-carbon steel grades, in particular in an electric oven.

Abstract: A probe is provided for measuring the wear of a wall in a metallurgical vessel. The probe includes at least two electrically conducting elements which extend generally mutually parallel, and a tubular sheath wherein the electrically conducting elements extend interiorly of said sheath, and are mutually insulated via a refractory insulator. The probe is adapted to be implanted in the transverse direction in the wall of a metallurgical vessel with the distal end of each of the two electrically conducting elements being disposed at the interior surface of said wall. A measurement system is connected to the opposite proximal ends of the electrically conducting elements for measuring an electrical characteristic of the circuit formed by said elements that depends on the length of the elements. The probe has a diameter less than 1 mm achieved by stretching after the components have been assembled into an intermediate assembly having a larger cross sectional area than the final cross section.

Abstract: The furnace includes a vessel closed by a floating roof, and a sealing means mechanism between the roof and the vessel. The sealing mechanism includes two joint surfaces, one of which is arranged on the peripheral edge portion of the roof whereas the other is arranged on the peripheral edge portion of the vessel. The first surface is substantially toric and the second surface substantially frustoconical. The joint surfaces permit the centering of the roof relative to the axis of the vessel. The peripheral edge portion of the vessel is provided with a coping element on which one of the joint surfaces is arranged.

Abstract: In order to regulate the combustion air flow rate of a flue gas collection device (1) of a metallurgical reactor (2) comprising a combustion chamber (4) supplied with air by a variable flow fan (9), a set value C.sub.0 for the oxygen content in the flue gases in the discharge duct (5) is set, the oxygen content M.sub.1 of the flue gases at the outlet of the combustion chamber (4) is measured, using C.sub.0 and M.sub.1, a setting C.sub.1 for varying the combustion air flow rate is calculated, a variable representative of the sudden variations of the flow rate of unburnt gases at the outlet of the metallurgical reactor (2) is measured and a setting C.sub.2 for the combustion air flow rate is calculated to achieve complete combustion of the unburnt gases in the flue gases; the values C.sub.1 and C.sub.2 are added to obtain a setting for the combustion air flow rate which is sent to the regulation device of the fan (9); these calculations may be carried out by electronic means (14, 15, 16).

Abstract: The inside of the metallurgical container is connected to a fan (105) through an exhaust duct (102). An additional gas is introduced in the intake part of the fan (105) preferably through the duct (102). The additional gas introduction flow is regulated in such manner that the gas pressure in the intake part of the fan (105) is maintained at a fixed value, via an adjusting valve (108) preferably placed in an additional duct (107) connected to the exhaust duct (102). A control system (110) regulates the opening and closing of the adjusting valve (108) in such manner as to maintain the gas pressure in the intake part of the fan (105) constant.

Abstract: A method for exhausting gases or fumes from a metallurgical container through a duct connected to the intake of a pump while introducing an additional gas stream into the pump is described. The additional gas stream ensures a constant gas pressure at the intake portion of the pump.