Gearbox assembly for a charging installation of a metallurgical reactor

Abstract

A gearbox assembly for a charging installation of a metallurgical reactor includes a stationary casing housing a gear assembly. The casing includes a bottom section with a central opening. The assembly further includes a rotor mounted within the casing for rotation about a first axis, which defines an axial direction. The rotor includes a support for the gear assembly, wherein a lower section of the support is disposed within the central opening. To provide for a better protection of a gear assembly, the bottom section includes a first annular portion extending radially inwards to a first radius. The lower section has a second annular portion extending radially outwards to a second radius that is greater than the first radius. The second annular portion is disposed adjacent to the first annular portion. The first annular portion includes a ring element disposed for sliding contact with the second annular portion.

Claims

1. Gearbox assembly for a charging installation of a metallurgical reactor, the assembly comprising: a stationary casing for housing a gear assembly, the casing comprising a bottom section with a central opening, a rotor mounted within the casing for rotation about a first axis, which defines an axial direction, the rotor comprising a support for the gear assembly, a lower section of the support being disposed within the central opening, wherein the bottom section comprises a first annular portion extending radially inwards to a first radius, and the lower section has a second annular portion extending radially outwards to a second radius that is greater than the first radius, said second annular portion being disposed adjacent to said first annular portion, and wherein the first annular portion comprises a ring element disposed for sliding contact with the second annular portion.

2. Gearbox assembly according to claim 1, wherein the second annular portion is disposed for sliding contact with the first annular portion.

3. Gearbox assembly according to claim 1, wherein the first annular portion is disposed axially above the second annular portion.

4. Gearbox assembly according to claim 3, wherein the first annular portion comprises a downward projecting portion.

5. Gearbox assembly according to claim 1, wherein the ring element is at least partially made of brass.

6. Gearbox assembly according to claim 1, wherein the ring element is at least indirectly connected to a bottom plate of the casing.

7. Gearbox assembly according to claim 6, wherein the ring element is connected to the bottom plate via an intermediate plate.

8. Gearbox assembly according to claim 1, wherein a lubricant is disposed between the first annular portion and the second annular portion.

9. Gearbox assembly according to claim 8, wherein the first annular portion has at least one channel for the lubricant.

10. Gearbox assembly according to claim 9, wherein at least one supply pipe connected to said at least one channel.

11. Gearbox assembly according to claim 3, wherein the second annular portion is delimited on a radially outward side by an upwards extending nose section.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Details of the invention will now be described with reference to the drawings, wherein

(2) FIG. 1 is a cross-sectional perspective view of a part of a charging installation;

(3) FIG. 2 is an enlarged view of the detail of the charging installation of FIG. 1; and

(4) FIG. 3 is a cross-sectional perspective view of the part of the charging installation of FIG. 1 in a deformed state.

DESCRIPTION OF PREFERRED EMBODIMENTS

(5) FIG. 1 shows a part of a charging installation 1 for a metallurgical reactor. The charging installation 1 comprises a gearbox assembly 2, which is largely symmetrical to a vertical axis A. It is understood that FIG. 1 only shows an arc-like section of about 60 of the whole assembly 2, which as a whole is more or less annular. The gearbox assembly 2 comprises a stationary casing 3 for housing a gear assembly (not shown). The casing 3 comprises a top section 3.1, a lateral section 3.2 and a bottom section 3.3. In the embodiment depicted, the top section 3.1 and the lateral section 3.2 are formed as one piece and the bottom section 3.3 is mounted to them. However, other configurations are possible. The overall shape of the casing 3 is annular and the shape of the lateral section 3.2 is cylindrical. The bottom section 3.3 comprises a bottom plate 6 which is essentially disposed perpendicular to the axis A. Radially inwards of the bottom plate 6 is an intermediate plate 7, which also essentially extends perpendicular to the axis A. On a radially innermost part of the intermediate plate 7, a brass ring 8 is fixed to its underside. Both plates 6, 7 consist of arc-like segments, although they could also be formed as one piece. The intermediate plate 7 is mounted to the bottom plate 6 and the ring 8 by bolts to allow for an easy dismantling. The bottom section 3.3, which defines a central opening 9 is facing the reactor (not shown) in operational state. Below the bottom plate 6 is installed a lower heat shield 12, which comprises a cooling system and a refractory layer, which will not be depicted in detail herein.

(6) A cylindrical support 4 for the gear assembly is mounted on the casing 3 by means of a roller bearing 5, which is disposed near the top section 3.1. A lower section 4.1 of the support 4 is disposed within the opening 9. In this lower section 4.1, the support 4 comprises a flange member 10 with a flange section 10.1, which extends radially outward. The flange member 10 is made of abrasion resistant material, such as e.g. steel. As can be seen from FIG. 1 and the enlarged view in FIG. 2, the flange section 10.1 radially extends to a radius that is greater than an inner radius of the intermediate plate 7 and the ring 8. Therefore, these elements 7, 8, 10 overlap in the axial direction. Furthermore, the ring 8 extends downwards from the intermediate plate 7. Thus, even if the ring 8 is not in contact with the flange member 10, the path from the underside of the gearbox assembly 2 to its interior is complicated and long, whence dust and/or hot gases cannot get easily inside.

(7) This effect is largely improved by the fact that grease (not shown) is disposed between the ring 8 and the flange section 10.1, whereby these elements 8, 10.1 are in sliding contact with each other. The grease, on the one hand, serves as a lubricant; on the other hand, it functions as a sealing media. The grease is supplied via a plurality of supply pipes 11, one of which is shown in FIGS. 1 and 2. Each supply pipe 11 is connected to a channel 8.1 (see FIG. 2), which runs annularly around the ring 8. The function of the channel 8.1 is to supply the grease to the contact surface between ring 8 and flange section 10.1 of the flange member 10 and also to distribute it circumferentially. While the grease is paste-like at room temperature, it becomes liquid and rather thin at elevated temperatures, which may occur during the operation of the metallurgical reactor. Such elevated temperatures would, under normal operating conditions, be up to about 200 C. To prevent the liquefied grease from flowing radially outwards and being lost, the flange member 10 comprises, on the radially outermost part of the flange section 10.1, an upwards-facing nose section 10.2, which forms a confinement.

(8) While FIG. 1 shows the components of the gearbox assembly 2 at normal working pressure, FIG. 3 shows a deformed state under elevated pressure. The metallurgical reactor pressure, which in particular affects the radially inner parts of the assembly 2, leads to an elevation of the inner parts of the top section 3.1 relative to the outer parts. Therefore, the bearing 5 and the support 4 are lifted. However, since the flange section 10.1 of the flange member 10, which is part of the support 4, is disposed under the ring 8, the lifting does not lead to a disconnection of the flange member 10 from the ring 8. On the contrary, these two parts 8, 10 are pressed together even more tightly. I.e. the sealing effect becomes greater as the temperature rises. As can be seen from FIG. 3 the, bottom plate 6 is also deformed as the intermediate plate 7 and the ring 8 are lifted by the flange member 10. The supply pipe 11 is flexible enough to stay in contact with the channel 8.1, whence grease may be supplied even under elevated temperatures.

(9) It is understood that the deformation of the gearbox assembly 2 is shown in FIG. 3 in an exaggerated way. However, since the sealing effect of the flange member 10 and the ring 8 is largely improved when these elements 8, 10 are in sliding contact with each other, it is a considerable advantage that the deformations even serve to improve the connection.