The present invention relates to a device for fastening a well block to a vessel containing metal melt which well block forms a spout of the vessel and has a through opening able to be fastened in a housing fixable to the vessel, and to a well block.
Well blocks are used in particular in continuous casting lines with vessels for the casting of metal melt, in particular as a fixed spout element with these types of Tundish. These Tundishs generally have a two-part casting channel which on the vessel side comprises a well block provided with a central through opening and on the die side a replaceable nozzle. The well block is embedded securely in the vessel bottom here, in particular is walled into the latter and is generally produced from a fire-proof ceramic material. The nozzle is produced from a heat-resistant fire-proof material and can easily be replaced. The separation point between the well block and the nozzle proves to be particularly critical here because at this separation point, if there is a leak, liquid steel can pass out and ambient air, in particular oxygen, is drawn into the melt flow and so has a negative impact on the quality of the metallic material. Therefore, this separation point should be as leakproof as possible, but is prone to serious cracking during the casting process.
It has therefore also already been proposed to prevent the increased formation of fissures and cracks in the region of the separation point with the aid of a specially configured nozzle. Such nozzles have a stop surface which can be subjected to contact forces in order to press the nozzle against the well block. Unfortunately, these devices prove to be mechanically complex and do not lead to the desired long-term stability.
It is therefore the object of the present invention to provide a device with which a well block for a metal melt vessel can be fastened easily in a housing that can be fixed onto the vessel such as to be stable in the long term.
According to the invention, this object is achieved by a device in which the well block can be fastened by means of at least one clamping wedge insertable transversely to its through opening such that the respective clamping wedge, or a clamping jaw coupled to the clamping wedge, engages against a clamping surface formed on the circumferential surface of the well block and clamps the well block by wedging, and by a well block for use in the device and which includes a base shoulder for resting against a carrier plate of a nozzle exchanger and which well block is provided on the vessel side of the base shoulder with a clamping seat with an adapted cross-section.
With this device according to the invention the formation of cracks in the region of the reference surface between the well block and for example a nozzle can be effectively prevented over the whole casting time.
The well block, which can be fastened in a housing that can be fixed to the metal melt vessel, can be fastened by means of at least one clamping wedge that can be inserted transversely to its through opening, the respective clamping wedge or a clamping jaw coupled to the latter engaging against a clamping surface formed on the circumferential surface of the well block and clamping the well block.
In one particular embodiment of the present invention the housing comprises a nozzle exchanger with a carrier plate and a wedge guide plate, the wedge guide plate being able to be connected securely to the carrier plate. The wedge guide plate has an opening for receiving the well block and at least one guide groove partially overlapping this opening for guiding and supporting a clamping wedge such that the wedge can press flat and permanently onto the well block with its inclined wedging surface.
One particular design of the clamping wedge makes it possible to produce a permanent mechanical tension, i.e. a tension equalising heat and vibrations, between the wedge guide plate and the well block and thus also prevents the formation of cracks in the region of the reference surface during the casting process.
Further embodiments of this device have the features of for example, the at least one clamping wedge being guided in the carrier plate such that it moves along the co-operating wedge surfaces provided on it and on the carrier plate and so executes a quasi-transverse movement with respect to its direction of displacement.
In particular, a well block which is suitable for use in this type of device has a clamping seat co-operating with the wedge surface on the vessel side.
The clamping wedges according to the invention can be inserted, re-tensioned or replaced without any special tool, and this substantially simplifies upkeep.
In the following exemplary embodiments and further advantages of the invention are described in more detail by means of the figures. These show as follows:
According to the invention, a wedge guide plate 4 is provided between this carrier plate 3 and the base plate 19. This wedge guide plate 4 has a circular opening 5 through which the well block 1 passes in the fitted state. For this purpose, the well block 1 is provided with a sloped clamping surface 13. Moreover, this wedge guide plate 4 has at least one guide groove 7 into which a clamping wedge 6 can be inserted. This clamping wedge 6 is supported by its support parts 11, 11′ lying flat against a support surface 8 of this guide groove 7. The guide groove 7 is arranged such that it is overlapped by the circular opening 5 and a cut-out 9 is formed opposite the support surface 8 in the guide groove 7. Preferably, the wedge guide plate 4 is formed by two guide grooves 7, 7′ running parallel and into which clamping wedges 6, 6′ can be introduced. In the fitted state, these clamping wedges 6, 6′ lie with their wedging surface 12 with force fit against the clamping surface 13 of the well block 1.
A preferred embodiment of the clamping wedge 6 according to the invention is shown in
The device illustrated in cross-section in
It goes without saying that the well block 1 can be provided, instead of with a clamping seat 15, with a clamping lug 16 which, as can be seen from
In a further configuration of the well block 1, as shown in
The well block 1 is fastened by means of clamping wedges 36 displaceable transversely to its through opening D such that a clamping jaw 35 coupled to the respective clamping wedge engages against a clamping surface 13 formed on the circumferential surface of the well block 1. The respective clamping wedge 36 is guided here in the carrier plate 33 in its longitudinal extension and transversely to the latter, and the clamping jaw 35 coupled to the latter is guided displaceable quasi transversely thereto. The clamping wedge 36 moves here along the co-operating wedge surfaces 36′, 39 provided on it and on the carrier plate 33, a cam 41′ moreover being assigned to it which engages in a longitudinal groove 41 in the carrier plate 33 running parallel to the wedge surface 39.
The clamping jaws 35 on their part are guided by means of guide cams 35′ in a respective groove 37′ of a covering plate 37 that can be fastened to the carrier plate 33 almost radially to the circular well block circumference. Moreover, the clamping jaws 35 respectively have a downwardly projecting bolt 35″ which is guided in an elongate groove 42 in the clamping wedge 36, this groove 42 running tangentially to the circular well block circumference and not parallel to the corresponding wedge surface 39, so that when displacing the clamping wedge 36 this desired transverse movement of the clamping jaw 35 takes place.
The clamping of a well block takes place in such a way that when the clamping wedges 36 are drawn away from the well block 1, the clamping jaws 35 on their part are displaced towards the well block 1 and clamp the latter on both sides on its annular clamping surface 13. Advantageously, two rounded clamping surfaces 43 are respectively provided on the clamping jaws 35 for optimal clamping. By means of this clamping force acting downwardly at an angle, the well block 1 is pressed with its base shoulder 14 against a reference surface 44 at the opening in the carrier plate 33 so that the well block is always positioned at the same height in relation to the nozzle exchanger.
When the clamping jaws 35 are released from the well block 1, the clamping wedges 36 are pushed or pressed against the well block, and this enables easy handling.
The invention is sufficiently demonstrated by the exemplary embodiments described above. It could, however, also be illustrated by further variations. It thus goes without saying that the clamping surface 13 can for example be in the form of a circumferential annular surface or of a polygon surface.
A fire-proof sleeve can also generally be used as a well block, and a conventional slide closure or the like could also be provided instead of a nozzle exchanger.
It is also conceivable as a variation for just one clamping wedge to be able to be provided with or without a clamping jaw, a fixed stop or the like then being provided on the opposite side of the well block 1.
Number | Date | Country | Kind |
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0813/11 | May 2011 | CH | national |
0196/12 | Feb 2012 | CH | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2012/001803 | 4/26/2012 | WO | 00 | 10/30/2014 |
Publishing Document | Publishing Date | Country | Kind |
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WO2012/152383 | 11/15/2012 | WO | A |
Number | Name | Date | Kind |
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3679105 | Ratcliffe | Jul 1972 | A |
4802655 | Bates | Feb 1989 | A |
5037072 | King et al. | Aug 1991 | A |
5314099 | Butz | May 1994 | A |
6772922 | Renard | Aug 2004 | B2 |
20060049555 | Hanse | Mar 2006 | A1 |
Number | Date | Country |
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1217401 | Dec 1970 | GB |
2012152383 | Nov 2012 | WO |
Number | Date | Country | |
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20170165747 A1 | Jun 2017 | US |