Claims
- 1. A method of removing and installing a top section of a steelmaking vessel, the vessel including a lower body section with said top section being detachably secured thereto, there being an operating platform including a vessel charging side alongside of said vessel, said vessel top section further being provided with lift bracket means on that side of the vessel nearest the charging side of the operating platform in the upright position of the vessel, and said body section being mounted for rotation about a horizontal axis, the method including
- (a) providing a hinge connection between the top section and the body section of the vessel such that the hinge axis thus defined is parallel to the rotation axis of the vessel, said hinge being located to that side of the vessel which is remote from the charging side of the operating platform in the upright position of the vessel;
- removing the vessel top section by:
- (b) rotating the body section about the rotation axis from an upright position toward the charging side of the operating platform while simultaneously applying lifting forces to said vessel top section via the lift bracket means to support the same whereby the top section pivots relative to said body section about the hinge axis, and continuing the rotation of the body section while supporting the top section and controlling the orientation thereof so that the top section is carried out over the operating platform and progressively lowered onto same;
- (c) separating the top section from the body section at the hinge connection and subsequently effecting repair or replacement of the top section;
- and subsequently installing the repaired or a replacement vessel top section by:
- (d) locating the top section on the operating platform;
- (e) connecting the top section to the body section via the hinge connection, and
- (f) rotating the body section from an inclined position toward an upright position while simultaneously applying lifting forces to the top section via the bracket means to support the top section and to control the orientation thereof such that the top section is carried away from the operating platform and gradually is pivoted relative to the body section about the hinge axis back into close juxtaposition with the body section.
- 2. A method of removing a top section of a steelmaking vessel, the vessel including a lower body section with said top section being detachably secured thereto, there being an operating platform including a vessel charging side alongside of said vessel, said vessel top section further being provided with lift bracket means on that side of the vessel nearest the charging side of the operating platform in the upright position of the vessel, and said body section being mounted for rotation about a horizontal axis, the method including
- (a) providing a hinge connection between the top section and the body section of the vessel such that the hinge axis thus defined is parallel to the rotation axis of the vessel, said hinge being located to that side of the vessel which is remote from the charging side of the operating platform in the upright position of the vessel;
- (b) rotating the body section about the rotation axis from an upright position toward the charging side of the operating platform while simultaneously applying lifting forces to said vessel top section via the lift bracket means to support the same whereby the top section pivots relative to said body section about the hinge axis, and continuing the rotation of the body section while supporting the top section and controlling the orientation thereof so that the top section is carried out over the operating platform and progressively lowered onto same, and
- (c) separating the top section from the body section at the hinge connection.
- 3. A method of installing a top section of a steelmaking vessel, the vessel including a lower body section with said top section being detachably secured thereto, there being an operating platform including a vessel charging side alongside of said vessel, said vessel top section further being provided with lift bracket means on that side of the vessel nearest the charging side of the operating platform in the upright position of the vessel, and said body section being mounted for rotation about a horizontal axis, the method including
- (a) providing interconnectable hinge portions on both the top section and the body section of the vessel such that the hinge axis defined by the hinge portions when connected together is parallel to the rotation axis of the vessel, said hinge, in the installed condition of the top section, being located to that side of the vessel which is remote from the charging side of the operating platform when the vessel is upright;
- (b) locating the top section on the operating platform, the body section being in an inclined position with the hinge portion thereon adjacent the hinge portion on the top section;
- (c) connecting the top section to the body section via the hinge portions;
- (e) rotating the body section from the inclined position toward an upright position while simultaneously applying lifting forces to the top section via the bracket means to support the top section and to control the orientation thereof such that the top section is carried away from the operating platform and gradually is pivoted relative to the body section about the hinge axis into close juxtaposition therewith;
- (f) and securely fastening said top section to the body section of the vessel.
Priority Claims (1)
| Number |
Date |
Country |
Kind |
| 281398 |
Jun 1977 |
CA |
|
BACKGROUND OF THE INVENTION
This invention relates to a method for facilitating the rapid and convenient installation and removal of the top section of a steelmaking vessel of a type that is rotatably mounted i.e. provided with trunnions.
Those skilled in the art know that oxygen converter vessels and the like are subjected to intense heat during the refining of metal, such as steel, and thus have to be periodically repaired and particularly to have their refractory linings replaced from time to time. The top section of an oxygen vessel is particularly subject to severe operating conditions and must be repaired or replaced more often than the body of the vessel itself. In the experience of the assignee of the present invention, oxygen vessel top sections have a service life of approximately four years and produce some 15,000 heats. Other steelmakers using similar vessels have longer or shorter intervals between repairs, depending on their operating conditions.
The methods commonly employed in the industry to change vessel tops are relatively complex, time-consuming and expensive.
One popular method is to invert the vessel and to lower the top section with jacks onto a transfer car mounted on the tracks used for the slag and steel cars and to then move it from under the vessel to an adjoining aisle for transfer with an overhead crane. On replacement, the operation is reversed. The replacement top is placed onto the transfer car in the inverted position, moved under the vessel and then slowly jacked up into position against the inverted lower portion of the vessel.
Another method involves using a very heavy porter-bar with appropriate counter balancing mounted from an overhead crane (such as the charging aisle crane) to reach in under the gas hood and to lift the top section out and back in. The porter-bar would have to be a very large and expensive device for the load to be lifted and, in addition, would require the availability of a very high capacity overhead crane to handle the heavy loads involved.
Another technique involves building a strong structural support on the operating platform to the approximate height of the vessel joint which also cantilevers over to the vessel top cone joint, and then moving the vessel top across the support frame on rollers for transfer out on removal or movement in on replacement.
If overhead building structural steel of sufficient strength is available, basic rigging techniques may be used in conjunction with the available overhead crane to lift and transfer the suspended top section away from or into position on the vessel lower section. The assignee of the present invention used this technique during erection and it took about 10 hours to only place a top section into position.
The above-noted prior art techniques are very time consuming and can take from 8 to 24 hours to complete. This represents a substantial expense in terms of manpower and equipment time and in terms of lost production.
It is a principal object of the invention to provide an improved technique which facilitates the rapid and convenient installation or removal of a vessel top section either during initial erection or in the course of subsequent rebuilding or repairing of a vessel.
Accordingly, the invention provides a method of removing and/or installing a top section of a steelmaking vessel, the vessel including a lower body section with said top section being detachably secured thereto, there being an operating platform including a vessel charging side alongside of said vessel, said vessel top section further being provided with lift bracket means on that side of the vessel nearest the charging side of the operating platform, and said body section being mounted for rotation about a horizontal axis. The method includes providing a hinge connection between the top section and the body section of the vessel such that the hinge axis is parallel to the rotation axis of the vessel, said hinge being located to that side of the vessel which is remote from the charging side of the operating platform. The vessel top section is removed, in accordance with one aspect of the invention, by rotating the body section about the rotation axis from an upright position toward the charging side of the operating platform while simultaneously applying lifting forces to said vessel top section via the lift bracket means to support the same whereby the top section pivots relative to said body section about the hinge axis. The rotation of the body section is continued while supporting the top section and controlling the orientation thereof so that the top section is carried out over the operating platform and progressively lowered onto same. The top section is then separated from the body section at the hinge connection and subsequently repaired or replaced. The method of installing a repaired or a replacement vessel top section includes locating the top section on the operating platform and connecting the top section to the inclined body section via the hinge connection. The body section is then rotated from the inclined position toward the upright position while simultaneously applying lifting forces to the top section via the bracket means to support the top section and to control the orientation thereof. By virtue of this action the top section is carried away from the operating platform and gradually is pivoted relative to the body section back into close juxtaposition therewith following which the body section and top section are secured together in any suitable fashion.
By using the above described method, it has been found that the time required to change the top section of an oxygen vessel can be reduced from 8 to 24 hours (depending on the prior art technique used) to something less than 3 and 1/2 hours (again depending somewhat on conditions). The savings in time and cost are substantial.
In the case of new vessels, the hinge and bracket arrangements may be included in the design at the time of fabrication. The hinge and bracket devices can also be economically and quickly added to and removed from existing vessels with a flanged (or even without a flange) top section to facilitate top section removal and replacement during a rebuild and need not be a permanent feature of the vessel.
The invention will now be described by way of example with reference being made to the drawings appended hereto.
US Referenced Citations (4)
Foreign Referenced Citations (1)
| Number |
Date |
Country |
| 954148 |
Apr 1964 |
GB |
Patent Grant
4130924
