Abstract: A method for detecting a leakage in the area of at least one cooling device of a furnace, wherein, in the event of a leakage, liquid coolant gets into a furnace chamber of the furnace from the at least one cooling device, and wherein a stream of exhaust gas is continuously removed from the furnace chamber over a period of time Z. The steps include dividing off a representative partial stream from the stream of exhaust gas during the period of time Z; condensing vaporous constituents contained in the partial stream; determining a stream of condensate obtained; comparing the stream of condensate obtained with a condensate-stream limit value; and indicating a leakage if the stream of condensate exceeds the condensate-stream limit value. Also a device for carrying out the method and a furnace with such a device are disclosed.

Abstract: A burner-lance unit (1) includes at least two gas connections (2a, 2b, 2c), a burner tube (3), and a lance tube (4) that is placed concentrically in the burner tube (3). The burner tube (3) and the lance tube (4) both have a gas inlet end and a gas outlet end (15). The lance tube (4) has a de Laval nozzle (4a) at the gas outlet end thereof. The de Laval nozzle (4a) is releasably connected to the lance tube (4). The burner tube (3) has a burner nozzle (3a) which is releasably connected to the burner tube (3).

Abstract: A metallurgical melting vessel has a vertical shaft, surrounded by a housing wall, which receives steel scrap. At least one closure element, having laterally spaced-apart fingers extending parallel to one another, is mounted such that it can move between a closed position and an open position. In the closed position, the fingers protrude at least partially into the shaft for the purpose of holding back steel scrap. In the open position, the fingers free the shaft at least to such an extent that the steel scrap can fall from the shaft into the melting vessel. The at least one closure element is mounted so as to be movable from the side of the shaft into the shaft and laterally thereoutof.

Abstract: A burner-lance unit (1) includes at least two gas connections (2a, 2b, 2c), a burner tube (3), and a lance tube (4) that is placed concentrically in the burner tube (3). The burner tube (3) and the lance tube (4) both have a gas inlet end and a gas outlet end (15). The lance tube (4) has a de Laval nozzle (4a) at the gas outlet end thereof. The de Laval nozzle (4a) is releasably connected to the lance tube (4). The burner tube (3) has a burner nozzle (3a) which is releasably connected to the burner tube (3).

Abstract: A melt metallurgical installation has a melting furnace for melting scrap metal and a charging region for the melting furnace which is located above the melting furnace. The installation further has a charging element, which has been filled with scrap metal intended for the melting furnace and can be moved in a movement direction into the charging region where it can be emptied and then moved again, in the empty state, against the movement direction out of the charging region. The charging region is enclosed by a hood such that the charging region, including the charging element which has been placed in the charging region, is closed at the top and on the sides. The hood has at least one upper extraction opening through which the waste gases and dust developing in the hood can be extracted out of the hood.

Abstract: An electric arc furnace (2) and to a method for operating an electric arc furnace having at least one electrode (4a, 4b, 4c) for generating an electric arc (6a, 6b, 6c), in which the desired value of the current (I) guided to the electrode (4a, 4b, 4c) oscillates about a predetermined base value (I0).

Abstract: A device and a method for changing at least one electrode of a melt-metallurgical vessel which has a receiving device for molten metal and a vessel cover with one opening per electrode for covering the receiving device. The at least one electrode can be positioned by means of at least one electrode support. The electrode and its support, and optionally the vessel cover can be lifted and laterally pivoted about a perpendicular rotational axis by a lifting and pivoting device. At least two electrode changing stations next to the receiving device are either adjacent to each other on a circular path about the rotational axis in a pivot range of the lifting and pivoting device or can be alternately brought onto the circular path about the rotational axis in the pivot range.

Abstract: A method for detecting a leakage in the area of at least one cooling device of a furnace, wherein, in the event of a leakage, liquid coolant gets into a furnace chamber of the furnace from the at least one cooling device, and wherein a stream of exhaust gas is continuously removed from the furnace chamber over a period of time Z. The steps include dividing off a representative partial stream from the stream of exhaust gas during the period of time Z; condensing vaporous constituents contained in the partial stream; determining a stream of condensate obtained; comparing the stream of condensate obtained with a condensate-stream limit value; and indicating a leakage if the stream of condensate exceeds the condensate-stream limit value. Also a device for carrying out the method and a furnace with such a device are disclosed.

Abstract: A burner insert for an arc furnace has a support frame which can be inserted into a wall opening of a side wall of the arc furnace and a burner arranged in the support frame. The support frame is pivotably mounted around a pivot axis relative to the side wall between a park position and an operating position in the installed state of the burner insert. In the park position, the support frame and burner are located outside and, in the operating position, at least partially inside an inner chamber of the arc furnace.

Abstract: A metallurgical melting vessel has a vertical shaft, surrounded by a housing wall, which receives steel scrap. At least one closure element, having laterally spaced-apart fingers extending parallel to one another, is mounted such that it can move between a closed position and an open position. In the closed position, the fingers protrude at least partially into the shaft for the purpose of holding back steel scrap. In the open position, the fingers free the shaft at least to such an extent that the steel scrap can fall from the shaft into the melting vessel. The at least one closure element is mounted so as to be movable from the side of the shaft into the shaft and laterally thereoutof.

Abstract: A melt metallurgical installation has a melting furnace for melting scrap metal and a charging region for the melting furnace which is located above the melting furnace. The installation further has a charging element, which has been filled with scrap metal intended for the melting furnace and can be moved in a movement direction into the charging region where it can be emptied and then moved again, in the empty state, against the movement direction out of the charging region. The charging region is enclosed by a hood such that the charging region, including the charging element which has been placed in the charging region, is closed at the top and on the sides. The hood has at least one upper extraction opening through which the waste gases and dust developing in the hood can be extracted out of the hood.

Abstract: The invention relates to a method for operating a melt-metallurgic furnace (2), particularly an arc furnace, during the operation of which a number of operating parameters are maintained within predetermined thresholds, wherein for this purpose a control or regulating device (1) is utilized. In order to obtain greater efficiency of the furnace, the invention provides that the control or regulating device (1) has a conventional control or regulating device (9) and a fuzzy regulating device (10), which each feed their correcting variables to a mediator (11), wherein the mediator (11) calculates the actuating signal used according to a predetermined weighting factor (F) from the correcting variable coming from the conventional control or regulating device (9) and from the fuzzy regulating device (10). The invention further relates to a melt-metallurgic furnace, particularly an arc furnace.