Abstract: An electric arc furnace (10) has an outer shell (12) and an inner refractory lining (24). During its operation the electric arc furnace (10) contains a bath (28) of molten metal which has a minimum and a maximum operational level (32). An inner cooling ring (23) of copper slabs (20), which are in thermo-conductive contact with the inner refractory lining (24) and equipped with spray cooling means (22), is mounted to the outer shell (12) in the region (34) between the minimum and the maximum operational level (32).

Abstract: A device (10), for moving a runner (12) of a shaft furnace between an upper tapping floor level (42), where the runner is in an operational position in front of a taphole of the furnace, and a lower service level (40), where the runner is accessible for replacement. The device (10) comprises a first support (28) and a second support (34) forming a base member (38), a carrier member (20) for bearing the runner, the carrier member having a first and a second longitudinal portion, a first lifting member (22) connected via a first articulation (26) to the first longitudinal portion and via a second articulation (30) to the first support, and a second lifting member (24) connected via a third articulation (32) to the second longitudinal portion and via a fourth articulation (36) to the second support. The base member (38), the carrier member (20) and the first and second lifting members (22, 24) together with the four articulations (26, 30, 32, 36) form a four-bar equivalent mechanism.

Abstract: A charging device for bulk material comprises a rotor having a substantially vertical axis of rotation a first drive for rotating the rotor and a chute supported by the rotor so as to be rotated with the latter. The chute can be rotated about its longitudinal axis. Its concavely curved sliding surface has a width that is diminishing from the top end to the bottom end of the chute, so that it is possible to vary the location where bulk material sliding down the chute channel leaves the latter by rotating the chute about its longitudinal axis.

Abstract: The inventive multi-level furnace comprises a furnace wall delimiting a cylindrical space having a vertical axis, a plurality of beds defining the levels inside said cylindrical space and at least one scraping arm which is provided with a wall scraper and associated with the bed in such a way that it is rotatable about the vertical axis of the furnace. During scraping arm rotation, said wall scraper defines a scraped area on the internal surface of the furnace wall which comprises a plurality of wall cavities forming a row of access openings in the scraped area, thereby making it possible to avoid the formation of a hardened crust adhered to the internal surface of the furnace wall and to develop braking shocks in the scraping arm.

Abstract: A cooled furnace wall comprises a furnace shell with an inner and an outer side and cooling plates lining the inner side of the furnace shell. Each of the cooling plates has a plate body and protruding connection pieces for supplying the cooling plate with a coolant. The furnace shell has connection openings therein for interconnecting the connection pieces of adjacent connection plates from the outer side of the furnace shell. At least one of the connection pieces is formed by a tube bend that protrudes from an edge face of the plate body and that has a connection end to extending through one of the connection openings in the furnace shell.

Abstract: A method of manufacturing a cooling plate includes providing a metallic plate body with a front face, a rear face and at least one channel extending through the metallic plate body beneath the front face; inserting with radial clearance a metallic tube into the channel so that both tube ends protrude out of the channel; and achieving a press fit of the tube within the channel by shrinking the section of the channel by the action of a metal-forming process applied to the plate body.

Abstract: A process for producing liquid smelting iron in an electric arc furnace includes several electrodes, equipped with a hearth, and containing a heel covered with a non-foaming liquid slag. The process further includes the reduction of the metallic fines, in order to form pre-reduced metallic fines containing an excess of free carbon; the hot transfer of the pre-reduced metallic fines within a curtain of inert gas into the heel contained in the electric arc furnace; the agitation of the heel by the injection of gas in such a manner that the formation of crusts is avoided; and the smelting of the pre-reduced metallic fines in the electric arc furnace in order to obtain the liquid smelting iron.

Abstract: A cooled furnace wall comprises a furnace shell with an inner and an outer side and cooling plates lining the inner side of the furnace shell. Each of the cooling plates has a plate body and protruding connection pieces for supplying the cooling plate with a coolant. The furnace shell has connection openings therein for interconnecting the connection pieces of adjacent connection plates from the outer side of the furnace shell. At least one of the connection pieces is formed by a tube bend that protrudes from an edge face of the plate body and that has a connection end to extending through one of the connection openings in the furnace shell.

Abstract: A device for distributing loose materials, arranged in a curtain of loose material tipped out from a means of conveying loose material includes a box with a top opening, at least one wall which extends transverse to the curtain of material inside the box to subdivide the box into at least two compartments, and at least two tipping-out means, one of the tipping-out means being associated with each of the compartments of the box, the tipping-out means being directed in such a way as to deflect the material received in the respective compartments into a distinct region of the hopper. The method for loading a hopper includes tipping loose material out in the form of a curtain of material over the hopper and splitting the curtain into at least two partial streams so as to deflect each of the partial streams towards a distinct region of the hopper.

Abstract: A spraying head for a granulating installation includes a slotted nozzle in which a nozzle channel having an oblong cross-section of flow is limited downwards by a floor surface, upwards by a top surface and laterally by a side face on each side. An oblong flow control body in the nozzle channel extends axially between the two side faces to limit the height of a nozzle slot. The control body is pivoted about a longitudinal axis to adjust the height of the nozzle slot. The control body is a cylindrical body having an oval cross-section and a central axis which is approximately centrically disposed between the floor surface and the top surface and pivoted about its central axis, such that underneath as well as below the control body a nozzle slot is formed, the height of which can be adjusted by pivoting the control body about its central axis.

Abstract: A rabble arm for a furnace includes an elongated metallic support core, at least one rabble tooth having a rabble portion and a fixing portion and a fixing device co-operating with the fixing portion for fixing the rabble tooth to the elongated metallic support core. The fixing portion includes a through hole through which the elongated metallic support core axially passes. The fixing device co-operates with the fixing portion around the through hole for fixing the rabble tooth to the elongated metallic support core.

Abstract: A device for monitoring the mass flow of a particulate solids flow in a pneumatic pipeline includes a measuring chamber and an impact body. Through an inlet connection the particulate solids flow is blown as a compact solid/gas jet onto the impact body, so as to impact thereon with substantially its whole cross-section. An acoustic transducer is associated with the impact body for sensing structure-born acoustic waves, which are generated by the compact solid/gas jet impacting onto the impact body, and transforming them into an output signal. Signal processing process the output signal so as to derive a value that is representative of the mass flow rate of the particulate solids flow.

Abstract: A device for distributing bulk materials includes a suspension rotor is mounted in a support frame which is capable of rotating about a substantially vertical axis of rotation. A chute is suspended to the suspension rotor and is tiltable about a substantially horizontal tilt axis. A first motor is capable of rotating the suspension rotor about its axis of rotation in a first direction, and a tilt controlling motor mounted in the support frame is capable of rotating about a substantially vertical axis of rotation. A tilting mechanism is also connected between the chute and the tilt controlling rotor, while a first braking device exerts a braking moment on the tilt controlling motor. A first control device controls the angle of inclination of the chute by controlled braking of the tilt controlling rotor.

Abstract: A method is presented for the treatment of slag from electric steel plants which comprises the following steps: (a) transference of the slag into a metallurgical receptacle; (b) defoaming of the slag in this metallurgical receptacle by adding a defoaming agent, preferably silica; (c) subsequent heating of the slag to make it fluid; and (d) forced cooling of the slag, for example by an aqueous granulation.

Abstract: A device for distributing materials in bulk includes a suspension rotor and a chute located below the suspension rotor. The chute is provided with two lateral suspension arms which are connected to the suspension rotor. A driving mechanism produces a pivoting torque capable of pivoting the chute, while a cylindrical suspension pin is associated with each suspension arm for pivotably connecting it to the suspension rotor. A control lever is connected to the suspension rotor, the driving mechanism being connected to the control lever so as to transmit to the latter the pivoting torque. A stop on the control lever and a counterstop on a suspension arm engage with each other to transmit the pivoting torque to the suspension arm. The stop and the counterstop are disengagable by a translation movement of the two suspension arms after withdrawal of the cylindrical suspension pins for removal of the chute.

Abstract: A device for monitoring the mass flow of a particulate solids flow in a pneumatic pipeline includes a measuring chamber and an impact body. Through an inlet connection the particulate solids flow is blown as a compact solid/gas jet onto the impact body, so as to impact thereon with substantially its whole cross-section. An acoustic transducer is associated with the impact body for sensing structure-born acoustic waves, which are generated by the compact solid/gas jet impacting onto the impact body, and transforming them into an output signal. Signal processing process the output signal so as to derive a value that is representative of the mass flow rate of the particulate solids flow.

Abstract: A drainage tank for granular material/liquid mixture includes a low part and a high part provided with a lid. A device for separating the liquid and the granular material is arranged in the low part. A device for evacuating excess liquid is arranged in the high part and includes a number of overflow sleeves passing through the lid. The overflow sleeves have, above the lid, an overflow edge that is adjustable in height.

Abstract: A loading device for a shaft furnace comprises a chute supported by a suspension rotor (28) in a fixed housing. The rotor (28) is fitted with a cooling circuit, supplied with liquid coolant via a rotating annular joint (44). The latter comprises a fixed ring (60) and a rotating ring (62), and is fitted in an annular leak collecting tank (46) formed by the suspension rotor (28). Fixed ring (60) is supported by the housing (12). Rotating ring (62) is supported entirely by fixed ring (60) via a bearing (64). Selective coupling means (65, 66) connect the rotating ring (62) to the suspension rotor (28) in such a way as to transmit a rotary moment of rotor (28) to rotating ring (62) selectively, while at the same time preventing other forces from rotor (28) being transmitted to rotating ring (62).

Abstract: A device for introducing poorly flowing bulk material into a feed line includes a swirl chamber connectable to a feed line so as to form an inlet aperture in a side wall of the swirl chamber. The device further includes a diffuser plate through which a loosening fluid may be introduced into the swirl chamber. The diffuser plate is arranged in the vicinity of the inlet aperture in the side wall of the swirl chamber. A device for producing a gas flow is also provided inside the swirl chamber, the gas flow being directed in the direction of the inlet aperture.

Abstract: A method of operating a multiple hearth furnace with a plurality of vertically aligned hearth floors includes feeding a first material onto the uppermost hearth floor and moving it over the hearth floor before it falls through a drop hole onto the next lower hearth floor. The first material is processed in this way from hearth floor to hearth floor to the lowermost hearth floor. A second material is fed onto one of the hearth floors to be mixed into the first material. This second material is moved separately from the first material in a separate annular zone of the hearth floor onto which it is fed before it is mixed into the first material, providing an efficient thermal preconditioning of the second material prior to mixing it with the first material without requiring any supplemental equipment.