Patent application title: Tiltable Metallurgical Vessel
Rudolf Gruber (Prambachkirchen, AT)
Martin Hirschmanner (Leonding, AT)
Gerhard Losbichler (St. Marien, AT)
Guenther Staudinger (Gmunden, AT)
IPC8 Class: AC21C546FI
Class name: Means for holding or supporting work receptacle with means movably supporting receptacle
Publication date: 2008-10-30
Patent application number: 20080265474
Patent application title: Tiltable Metallurgical Vessel
OSTROLENK FABER GERB & SOFFEN
Origin: NEW YORK, NY US
IPC8 Class: AC21C546FI
A tiltable metallurgical vessel having a carrying ring at least partially
around it. A metallurgical supporting bracket fastened on the
metallurgical vessel rests on the ring. The vessel is releasably fixed on
the support ring by a clamping device actuated by a pressure-medium
cylinder. The clamping means interacts with a locking bracket fastened on
the vessel. The clamping device moves between a release position,
releasing it from the locking bracket and clamping position, clamping the
locking bracket together with the support ring, The clamping device
comprises a housing, a clamping anchor, a pivot lever and a
pressure-medium cylinder, which acts on the pivot lever. The clamping
anchor is guided in a pivotable manner in a guide means in the housing.
The anchor is pivotably articulated on a pivotable lever, and the pivot
lever is supported in a pivotable manner in the housing.
1. A tiltable metallurgical vessel comprisinga metallurgical vessel, a
support ring which at least partially surrounds the metallurgical vessel,
the metallurgical vessel resting on the support ring;a clamping device
releasably fixing the metallurgical vessel on the support ring;a locking
bracket fastened to the metallurgical vessel, the clamping device
cooperating with the bracket, the clamping device being operable between
a release position releasing the locking bracket from the support ring
and a clamping position clamping the locking bracket together with the
support ring,the clamping device:comprising a guiding plate including a
guide thereon for controlling operable movement of a clamping anchor;a
clamping anchor operably movable to selectively clamp to the locking
bracket and to release clamping to the locking bracket; the clamping
anchor being connected with the guide for thereby guiding movement of the
anchor;a pivoting lever pivotable with respect to the plate and connected
with the anchor such that pivoting of the lever moves the anchor to clamp
to and release the bracket;a device for operating the pivoting lever such
that the clamping anchor is guided in a pivotable movable manner in the
guide in the plate, the anchor is pivotably articulated on the pivoting
lever and the pivoting lever is also pivotably supported by the plate
such that guided motion of the anchor selectively clamps and unclamps the
anchor to the bracket.
2. The tiltable metallurgical vessel as claimed in claim 1, whereinthe clamping anchor includes a clamping anchor shank and a clamping head on the shank the head including a first supporting surface;the locking bracket having an insertion slot for receiving the clamping anchor shank and having a second mating supporting surface for supporting the clamping head, wherein in the clamping position, the first supporting surface of the clamping head is pressed against the second mating support surface of the locking bracket and, in the release position, the clamping head has been pivoted to a position outside the insertion slot which allows a movement lifting the metallurgical vessel off the support ring.
3. The tiltable metallurgical vessel as claimed in claim 1 wherein the clamping device forms or comprises a toggle lever mechanism which is operable to trigger self-locking at a self-locking point in the clamping position, and a stop for limiting the displacement path of the mechanism.
4. The tiltable metallurgical vessel as claimed in claim 3, wherein the stop is formed by the slotted guide.
5. The tiltable metallurgical vessel as claimed in claim 2, further comprising an expansion element operable on the clamping device.
6. The tiltable metallurgical vessel as claimed in claim 5, wherein the expansion element is integrated in the clamping anchor.
7. The tiltable metallurgical vessel as claimed in claim 6, wherein the expansion element is formed by a cup spring assembly.
8. The tiltable metallurgical vessel as claimed in claim 2, wherein the guide is arranged in the plate of the clamping device such that, during the movement of the clamping head from the clamping position into the release position, in a first movement phase, the clamping head of the clamping anchor is moved such that the first supporting surface is lifted off the second mating supporting surface on the locking bracket, and during a further movement phase of the clamping head, the clamping head of the clamping anchor (is moved with a pivoting movement out of the insertion slot of the locking bracket.
9. The tiltable metallurgical vessel as claimed in claim 8, wherein the guide in the plate of the clamping device comprises an arcuate guiding groove and a guiding bolt of the clamping anchor engages and is guided in the groove in a sliding manner.
10. The tiltable metallurgical vessel as claimed in claim 1, wherein the clamping device is formed as a preassembled module and is releasably fastened to the support ring.
11. The tiltable metallurgical vessel as claimed in claim 18, wherein the pressure medium cylinder is a pneumatic cylinder.
12. The tiltable metallurgical vessel as claimed in claim 1, further comprising an enclosure fastened to the metallurgical vessel and surrounding the locking bracket that is open in the direction of the support ring.
13. The tiltable metallurgical vessel as claimed in claim 1, wherein the support ring is at a distance from the vessel.
14. The tiltable metallurgical vessel as claimed in claim 13, further comprising supporting brackets supporting the vessel on the ring.
15. The tiltable metallurgical vessel as claimed in claim 1, wherein the guide comprises a slot in the plate.
16. The tiltable metallurgical vessel as claimed in claim 1, further comprising a housing for the clamping anchor and the plate comprises a wall of the housing.
17. The tiltable metallurgical vessel as claimed in claim 16, wherein the guide comprises a slot in the plate.
18. The tiltable metallurgical vessel as claimed in claim 1, wherein the device for operating the pivoting lever comprises a pressure medium cylinder operable, or pivoting the lever.
19. The tiltable metallurgical vessel as claimed in claim 1, further comprising a plurality of the clamping devices spaced apart along the ring.
The invention relates to a tiltable metallurgical vessel with a
support ring which at least partially surrounds the metallurgical vessel
at a distance from it, supporting brackets which are fastened to the
metallurgical vessel resting on the support ring and the metallurgical
vessel being releasably fixed on the support ring by a number of clamping
devices which can be actuated by pressure medium cylinders, each clamping
device interacting with a locking bracket fastened to the metallurgical
vessel and the clamping device being formed in such a way that it can
move from a release position, releasing the locking bracket, into a
clamping position, clamping the locking bracket together with the support
ring, and vice versa.
Specifically, the invention relates to a clamping device for supporting and fastening a tiltable converter on a support ring which at least partially surrounds it at a distance.
Metallurgical vessels of this type, as are predominantly used in steel works for producing and refining steel melts, are exchangeable vessels which have to be changed at intervals over the course of time in order for it to be possible for their refractory lining to be renewed or for other repairs to be carried out on them.
Tiltable metallurgical vessels, such as converters, are exposed to high thermal loads on account of the metallic melts treated in them and release large amounts of heat to the environment through radiation. To keep the thermal loading on the supporting framework of the metallurgical vessel at a low level, the metallurgical vessel is therefore usually arranged in a support ring, which is designed either as a continuous annular welded structure or as an open horseshoe-shaped welded structure. The support ring can pivot about a horizontal axis and has support pins which are mounted in a supporting framework. The metallurgical vessel may be suspended in the support ring or rest on it or be supported on it. Possible design variants of this type are described in EP-B 0 029878 B1, in which a nonpositive connection is maintained between the support claws on the metallurgical vessel and support straps on the support ring by means of hasp screws. The tightened hasp screws reliably avoid lateral movement of the metallurgical vessel even in a tilted position of the vessel. However, manual unscrewing of the hasp screws not only takes up considerable time but is also extremely arduous work for the maintenance personnel on account of the action of heat, the release of dust, the risk of falling and the confined space available in this area, and can be carried out only with considerable expenditure on safety.
To minimize the risk of accidents for the maintenance personnel and to make the installation work easier, the fastening systems have been improved. For example, DE 102 51 964 A1 discloses a quick-acting fastening for a metallurgical treatment vessel on a support ring with which opposing vessel brackets and support ring brackets can be clamped together in a secured closed position by means of a toggle closure and can be easily released in an opposite actuating direction (release position). For clamping and releasing these toggle closures, a hydraulic handling device to be manually fitted is proposed, but the basic problem of hazardous use for the maintenance personnel is not really solved.
DE 25 11 610 A1 and EP 1 533 389 A1 already disclose embodiments of clamping devices which avoid the maintenance personnel being used directly for releasing the clamping elements on the support ring at a great height above the casting floor by the clamping and releasing operation being performed by hydraulic elements. In the embodiment according to FIG. 9 of DE 25 11 610 A1 and in the embodiment according to FIGS. 4a and 4b of EP 1 533 389 A1, the clamping device respectively comprises a pair of hooks with which a bracket on the converter can be engaged from behind in the manner of pincers, and consequently compressive forces acting in the direction of the support ring can be applied, fixing the converter in its position on the support ring. The arrangement of the linkage in the manner of a toggle lever mechanism ensures a self-locking clamping position of the clamping device. The embodiments of clamping devices that are otherwise represented in DE 25 11 610 A1 are much more sophisticated in their structural design and require successive actuation of pressure medium cylinders, a bearing bush locking element being pivoted into a clamping position in a first step and this bearing bush locking element being fixed by a tie anchor engaging over it in a second step. This last-cited embodiment is not suitable, however, for the specific location where it would be used.
The present invention aims to avoid these disadvantages and difficulties and is based on the object of proposing a tiltable metallurgical vessel in a further embodiment in which the production of a secured connection and the opening of this secured connection between a metallurgical vessel and a support ring can be carried out with a minimal number of components in an environment that is largely protected from the action of heat and the discharge of slag.
This object is achieved according to the invention by the clamping device comprising at least one housing, a clamping anchor, a pivoting lever and a pressure medium cylinder acting on the pivoting lever, by the clamping anchor being guided in a pivotably movable manner in a slotted guide in the housing and pivotably articulated on the pivoting lever and by the pivoting lever being pivotably supported in the housing.
An expedient further refinement of the device according to the invention consists in that the clamping anchor has a clamping anchor shank and a clamping head with a supporting surface, in that the locking bracket has an insertion slot for receiving the clamping anchor shank and a mating supporting surface for supporting the clamping head, in that, in the clamping position, the supporting surface of the clamping head is pressed against the mating surface of the locking bracket and, in the release position, the clamping head is positioned outside the insertion slot and allows a movement lifting the metallurgical vessel off the support ring. With this special design of the clamping anchor and the locking bracket, a central clamping force acting perpendicularly on the locking bracket and parallel to the axis of the converter is applied using only a single clamping anchor that can be pivoted in and out.
The fact that the clamping device forms or comprises a toggle lever mechanism which triggers self-locking at a self-locking point in the clamping position and the displacement path of which is delimited by a stop which is preferably formed by the end of the groove of the slotted guide means that the advantage that is in fact already achieved in the case of known clamping devices is also equally realized with the solution according to the invention of a simple construction. However, there is also the possibility of providing a stop delimiting the displacement path elsewhere in the housing of the clamping device or in some other way to achieve the same effect.
The clamping device is designed for a high clamping force, ensuring that the clamping effect is definitely maintained, with which forces and moments that occur specifically while the metallurgical vessel is being tilted during charging and emptying are taken into consideration. In order that the self-locking point of the toggle lever mechanism can be passed through, it is necessary that the clamping device is assigned an expansion element, with which tensile stresses otherwise occurring when the self-locking point is passed through are limited in their magnitude. The expansion element is expediently integrated in the clamping anchor. Preferably, the expansion element comprises a spring assembly, formed by a number of cup springs.
The clamping device is based on special kinematics. By arranging a special slotted guide in the housing of the clamping device, these kinematics are set in such a way that, during the transfer from the clamping position into the release position, in a first movement phase, the clamping head of the clamping anchor is moved such that it is lifted off the mating supporting surface on the locking bracket, consequently predominantly in a direction perpendicular to the mating supporting surface on the locking bracket, and that, in a further movement phase, the clamping head of the clamping anchor is moved with a predominantly pivoting movement out of the region of the insertion slot of the locking bracket. The special first movement phase, which comprises the lifting of the clamping head off the mating supporting surface on the locking bracket, has the effect of avoiding horizontal forces acting on the clamping device as a result of a frictional horizontal movement of the clamping head.
The slotted guide in the housing of the clamping device is formed by a slot which is arcuate in its longitudinal extent and in which a guiding bolt of the clamping anchor engages and is guided in a sliding manner.
The arrangement of all the components of the clamping device in a common housing which is not an integrated part of the support ring means that the clamping device forms a preassembled module which can be easily installed on corresponding wall elements of the support ring. This in turn gives rise to advantages for the maintenance personnel and the availability of the installation, since each clamping device can be exchanged within an extremely short time in every case that maintenance work becomes necessary.
Pneumatic cylinders are used with preference for actuating the clamping device.
Damage to the clamping device, and in particular the pressure medium cylinder, caused by slag and steel being thrown out, in particular during the blowing phase in a steel-making converter, or by slag and metal skulls falling from the mouth of the converter, can be avoided by the locking bracket being surrounded by an enclosure that is open in the direction of the support ring and this enclosure being fastened to the metallurgical vessel. In addition, the pressure medium cylinder and the moving parts of the clamping device are accommodated in a protected manner in the housing of the clamping device and possibly also shielded by components of the support ring.
Further advantages and features of the present invention emerge from the following description of an exemplary embodiment, which is not restrictive, reference being made to accompanying figures, in which:
FIG. 1 shows a prior-art converter supported in a support ring, in a schematic representation,
FIG. 2 shows the clamping device according to the invention in an intermediate position between the clamping position and the release position, in an oblique view,
FIG. 3a shows the arrangement of the clamping devices according to the invention on the support ring in the case of a converter vessel that is not represented, in the clamping position,
FIG. 3b shows the arrangement of the clamping devices according to the invention on the support ring in the case of a converter vessel that is not represented, in the release position,
FIG. 4 shows the clamping device according to the invention in the clamping position, in an intermediate position and in the release position,
FIG. 5 shows a longitudinal section through the clamping anchor with an expansion element,
FIG. 6 shows details of the slotted guide.
In FIG. 1, the basic construction of a converter installation in a steelworks is schematically represented in a side elevation. The converter 1, comprising a steel casing and a refractory lining, which lies against the inside of the latter but is not represented, is supported in a support ring 2 with a small distance from the converter. As a result, the thermal loading of the support ring caused by the hot converter vessel is kept at a low level. The support ring 2, usually formed as a horseshoe-shaped frame structure, is rotatably supported by means of two support pins 3a, 3b in a supporting framework 4 and provided with a tilting drive (not represented here), whereby the setting of a vertical or an inclined operating position of the converter for charging with feedstock, blowing the crude steel or tapping the liquid steel is made possible. Welded on the steel outer shell of the converter are a number of brackets 5a, 5b, with which the converter rests on the support ring 2 in bearings not represented any more specifically. The brackets 5a, 5b, and consequently the converter 1, are fixed in their predetermined position with respect to the support ring 2, and kept in this position even in the tilted operating position of the converter, by corresponding clamping devices 6a, 6b, which according to the prior art are formed by screw connections or by a linkage that is actuated by a pressure medium.
The clamping device 6 according to the invention is represented in FIG. 2 in a possible embodiment as a preassembled module in the installation position in relation to a locking bracket 7 that is welded on the converter (not represented). The clamping device 6 comprises a housing 8, which is made up of a number of steel plates and, as a welded structure, forms a frame for receiving the individual components of the clamping device 6. One or more supporting plates 8a, 8b of the housing with a machined mounting surface make it possible for the entire clamping device to be mounted quickly at the intended positions of the support ring 2 (FIGS. 3a, 3b). Provided on two supporting plates 8c that rise up perpendicularly from the supporting plate 8a and are positioned parallel to each other are slotted guides 10, which lie opposite each other and in which a clamping anchor 9 is guided in a sliding manner. Here, a guiding bolt 11 of the clamping anchor 9, two of which are provided opposite each other, respectively engages in the groove of a slotted guide 10. Pivoting levers 12 are pivotably mounted by their one end in a supporting bearing 13 in the supporting plates 8c. A pressure medium cylinder 14, formed as a pneumatic cylinder, is tiltably supported in bearing housings 15, which are likewise fastened to the supporting plates Bc. The pressure medium cylinder 14 acts with its piston rod 14a on the other end of the pivoting lever 12 at the pivoting joint 16. The clamping anchor 9 is preferably pivotably supported in a pivoting joint 17 in the middle of the pivoting lever 12. The movement of the clamping anchor 9 is consequently definitively set by the pivoting movement of the pivoting lever 12 in the supporting bearing 13 and by the course of the slotted guide 10. The clamping anchor 9 comprises a clamping anchor shank 18 and, at its end, a clamping head 19, which has a greater diameter than the clamping anchor shank 18. This produces an annular surface, which forms a supporting surface 20 on the underside of the clamping head 19 that is not visible in FIG. 2. With the clamping anchor shank 18, the clamping anchor 9 reaches through the locking bracket 7, which has a U-shaped insertion slot 21 in the region where the clamping anchor shank 18 passes through. In the edge region of the U-shaped insertion slot 21, a mating supporting surface 22 is formed, the supporting surface 20 and the mating supporting surface 22 coming into congruent alignment in the clamping position.
The clamping anchor 9 is provided with an expansion element 26, which is represented in FIG. 5 in a longitudinal section. The clamping anchor shank 18 is made up of two parts, an upper clamping anchor shank 18a, carrying the clamping head 19, and a lower clamping anchor shank 18b, mounted in the pivoting joint 17. The upper clamping anchor shank 18a is fastened in a positionally fixed manner in a housing 27a of a two-part housing 27a, 27b of the expansion element. The lower clamping anchor shank 18b passes through the bottom of the housing 27b and carries a pressure disk 28. Inserted in an annular recess of the housing 27b is a cup spring assembly 29 between the bottom of the housing 27b and the pressure disk 28. The two parts of the two-part housing are screwed to each other. This expansion element allows a lengthening of the clamping anchor shank 18 when the self-locking point of the kinematic system of the clamping device is passed through just before reaching the clamping position and in the very first phase of the releasing operation, whereby it is only made possible for the self-locking point to be passed through by the locking or releasing force that is to be applied by the pressure medium cylinder being limited.
The slotted guide 10 is assigned to the supporting plates 8c of the housing 8 of the clamping device lying opposite each other. It is substantially made up of arcuate guiding grooves 30, in which the guiding bolt 11 engages in a sliding manner. The guiding bolt 11 is connected to the clamping anchor 9 and oriented such that it is perpendicular to the longitudinal axis of the clamping anchor and parallel to the pivoting axis of the pivoting joint 17. In the clamping position, the guiding bolt 11 is in an end position in the guiding groove 30, as represented in FIG. 6. The wall of the guiding groove at this point forms a stop 31 limiting the clamping movement of the clamping device. The width of the groove is increased in this region, in order to create a free space for the guiding bolt if the support ring twists slightly as a result of the thermal influences. The arcuate form of the guiding groove is chosen such that there is an optimum lifting-off and clamping movement of the clamping anchor.
In FIGS. 3a and 3b, the support ring 2 is represented in an oblique view with the centering devices 24 that are necessary for receiving a converter and with three clamping devices 6. To provide a clearly presented representation, all that is indicated of the converter vessel itself are the locking brackets 7. The representations of the figure show three centering devices 24, which are substantially offset by 90° in relation to one another as they rise up from the supporting plate of the support ring and in which the converter to be mounted is centered in its position. Of the three clamping devices 6 that are arranged in a distributed manner on the horseshoe-shaped support ring, one clamping device respectively adjoins the end faces of the support ring and a further clamping device is positioned centrally on the outer lateral surface of the support ring. The clamping devices are formed as a preassembled module and mounted as such on the support ring. The pressure medium cylinders 14 are arranged in a specially protected region on the underside of the support ring. However, it is also possible to integrate the clamping devices in the support ring by the way in which they are constructed. FIG. 3a shows the clamping device in the clamping position A and FIG. 3b shows the clamping device in the release position B. Hereafter, the operation of clamping a converter to the support ring and releasing it is described in detail on the basis of the two operating positions and an intermediate position of the clamping device that are schematically represented in a series of images in FIG. 4:
The upper image shows the clamping device 6 and the locking bracket 7 in the clamping position. The guiding bolt 11 of the clamping anchor 9 is located in the lower end position of the slotted guide 10 and the pressure medium cylinder 14 is located in the end position provided for the clamping position. These positions are set in such a way that self-locking of the kinematic system is obtained and release of the clamping between the converter and the support ring is only possible after passing through the self-locking point when the pressure medium cylinder is subjected to corresponding pressure. This must involve overcoming the force of resistance applied by the cup spring assembly of the expansion element. The lifting movement of the clamping anchor, and in particular of the clamping head, off the mating supporting surface of the locking bracket is essentially determined by the slotted guide. When the pressure medium cylinder is subjected to further pressure, a lifting of the clamping head 19 off the mating supporting surface 22 is brought about in a first movement phase of the clamping anchor by a movement that takes place predominantly in a direction perpendicularly away from the mating supporting surface. In a further movement phase, a pivoting movement is predominantly imposed on the clamping head. In this phase, a position of the clamping anchor such as that represented in the middle image of the series of images is achieved. When the pressure medium cylinder is subjected to further pressure, the guiding bolt 11 of the clamping anchor 9 moves to the upper end point of the slotted guide 10 and the pressure medium cylinder 14 reaches the end position that corresponds to the release position of the clamping anchor. In this position, the clamping head is entirely outside the insertion slot 21 of the locking bracket 7, as represented in the lower image of the series of images of FIG. 4. In this release position, the converter can be lifted off the support ring or inserted into the support ring. The clamping of the inserted converter is performed by reversing the sequence of steps involved in the described release operation.
Patent applications by Guenther Staudinger, Gmunden AT