Patent Application
20240326122
The present invention relates to an oscillating table for continuous casting, intended to be used in the production of casting products, by means of which the oscillation of a continuous casting mould is achieved and which comprises torsion axles joined at the ends thereof to joining elements which guide a mobile portion of the oscillating table.
The table of the present invention enables greater precision in the guiding of the mould even with very high oscillation frequencies, ensures suitable torsional rigidity, reduces maintenance work and provides the mobile portion with stability in the oscillation movement thereof.
The oscillating table falls within the production process of a continuous casting plant, focusing on manufacturing of semi-finished metal products, which can be longitudinal products also known as casting products. The oscillating table has the task of producing a high-low oscillation movement in a structure through a predetermined oscillation frequency and amplitude, which is guaranteed in order to reach the production objective.
Traditionally, the state of the art has opted for solutions integrating bearings, subject to wear, which are disadvantageous since they require frequent maintenance with considerable costs and are time-consuming. Likewise, during the casting process of the steel product, unwanted movements of the oscillating table are generated due to the clearances of the bearings, the value of which is amplified at high oscillation frequencies.
Alternatives to solutions of this type are known in the state of the art, such as patent document EP1791664B1, which describes a moulding apparatus which is equipped with an oscillating table comprising a mobile structure, mounted in a supporting structure integral with the floor, wherein the mobile structure comprises a mould and is guided in an oscillation by the first elastic members having an elongated shape and arranged transversely to the casting direction. The table comprises a hydraulic actuator transmitting oscillations to the mould and two or more pairs of bars, arranged horizontally in a second direction basically transverse to the first elastic members and to the first casting direction, wherein a first end of each bar of each pair is fastened to the mobile structure and a second end is fastened to the supporting structure.
Patent document EP1996351B1 also discloses a casting device for continuous casting, comprising an ingot mould defining a casting direction and an oscillating table comprising a load-bearing structure fixed to the ground supporting said ingot mould, wherein said ingot mould can be guided in an oscillation by the first and second pairs of elastic bars arranged transverse to the casting direction. The apparatus comprises actuating means which transmit alternating pulses. Wherein, each elastic bar of each first and second pairs of elastic bars having a first end fixed to the ingot mould and a second end fixed to the load-bearing structure, in the opposite way to the corresponding ends of the immediately adjacent other bar of the same pair.
Thus, the oscillation tables known in the state of the art rigidly join the guide elements to the base and to the oscillating structure, which causes the oscillating tables to have clearance, causing the mobile portion to not have the necessary stability such that the trajectories are not precise and tend to describe an unwanted trajectory which is usually in the shape of an eight. Furthermore, semi-finished products can be generated wherein the oscillation marks are reflected and which entail high maintenance for repair and replacement.
The present invention aims to solve the problems mentioned in the state of the art. The present invention is an oscillating table for continuous casting, intended for manufacturing longitudinal metal elements comprising a supporting structure equipped with a base intended to be linked to a floor in an assembly situation, a mobile structure resting on the base and comprising a cavity intended to house a mould wherein the cavity defines a first casting direction perpendicular to the base and at least one actuating element linked to the mobile structure which transmits alternating oscillations in the first direction.
The oscillating table likewise comprises at least two pairs of torsion axles, which extend in planes transverse to the first direction, wherein at least the ends thereof work in torsion, comprising a first pair of axles arranged in planes parallel to each other and linked to the mobile structure and a second pair of axles arranged in planes parallel to each other and linked to the supporting structure and at least four longitudinal joining elements which are transverse to the pairs of torsion axles and to the first direction, arranged two by two on each side of the mobile structure, wherein each joining element is joined to one end of an axle of the first pair of axles and/or to one end of an axle of the second pair of axles, wherein the joining elements guide the mobile structure in the oscillation movement thereof.
The main advantage of the invention is that it provides the mobile structure with high stability, preventing it from following an unwanted oscillation path. Thanks to the configuration of the oscillating table, the mobile structure performs a C-shaped trajectory, preventing the trajectory from being in the shape of an eight. In this manner, the oscillation table is provided with a predetermined torsional resistance around a first direction which enables the oscillation of the mobile structure only in the casting direction. Thus, an oscillating table without clearance is achieved, such that precise trajectories, high working frequency and low maintenance are guaranteed. The oscillating table of the present invention can be suitable both for oscillating tables which follow a curved trajectory, and for those which follow a straight trajectory.
Preferably, the first pair of axles can be directly joined to the mobile structure and the second pair of axles can be directly joined to the supporting structure, such that the joining elements are joined at the ends thereof to the first pair of axles and to the second pair of axles. Thus, the joining elements are not linked at either of the ends thereof to the mobile structure or to the supporting structure.
The joining elements can be bending elements and the torsion axles can be torsion bars, wherein the bending elements can be leaf springs such that the required flexibility is given by the bending of the springs, which are more or less rigid. Alternatively, the joining elements can be rigid elements and the torsion axles can be torsion tubes.
When the first pair of axles are torsion bars, these bars can comprise first torsion bars which can be joined to the mobile structure through the bending elements. Specifically, the table can comprise two pairs of bending elements on each side and the bending elements are joined at one end to the mobile structure and at the other end to torsion bars wherein both torsion bars are directly joined to the supporting structure.
In order to perform the direct joint between the torsion axles and the mobile structure or the supporting structure, the table can comprise clamps which surround and retain the torsion axles and which are joined to the supports, such that the central area thereof remains fixed.
Preferably, the distance between the axles of the first pair of axles is smaller than the distance between the axles of the second pair of axles.
According to one of the aspects of the invention, the rigidity of the joining elements is the same, being able to be different between the bending elements of one same pair in an alternative embodiment.
Preferably, the table comprises at least one pair of damping elements linked to the base and to the mobile structure, which dampen the oscillating movement of the mobile structure. The damping elements are arranged in pairs and can be helical supports or pneumatic supports.
As for the actuating element, there can be a single actuating element facing the first pair of torsion axles joined to the mobile structure and causing the oscillation movement thereof. Alternatively, it may comprise two actuating means, facing each pair of bending elements respectively on each side of the mobile structure. The actuating element is preferably a mechanical or hydraulic cylinder equipped with at least one connecting bar.
As a complement to the description provided herein, and for the purpose of helping to make the features of the invention more readily understandable, in accordance with a preferred practical exemplary embodiment thereof, said description is accompanied by a set of drawings constituting an integral part of the same, which by way of illustration and not limitation, represent the following:
Resting on the base (2) is a mobile structure (3) comprising a cavity (4), not visible in the figure, which houses a continuous casting mould (5) through which the metal is introduced in liquid state into the upper portion thereof and a semi-finished product (20) comes out through the lower portion of the oscillating table. The cavity defines a first casting direction (X) perpendicular to the base (2). Additionally, a stirrer (23) is seen surrounding the mould (5).
The oscillating table in the figure comprises an actuating element (6) linked to the mobile structure (3) and transmitting alternating oscillations in a first direction (X) to the mobile structure (3) causing the oscillation movement thereof.
The oscillating table is equipped with two pairs of torsion axles (7, 8, 9, 10) arranged in a plane transverse to the first direction (X) wherein at least the ends thereof work in torsion and comprise a first pair of axles (7, 8) arranged in planes parallel to each other and directly linked to the mobile structure (3) through the central area thereof by means of clamps (15) and a second pair of axles (9, 10) arranged in planes parallel to each other and directly linked to the supporting structure (1) through the central area thereof by means of clamps (15).
Likewise, the oscillating table comprises four longitudinal joining elements (11, 12), transverse to the pairs of torsion axles (7, 8, 9, 10), arranged two by two on each side of the mobile structure (3), and to the first direction (X). Specifically, one end of each joining element (11, 12) is joined to one end of an axle of the first pair of torsion axles (7, 8) and the other end of the joining element is joined to one end of a second torsion axle (9, 10).
In the embodiment shown, the torsion axles (7, 8, 9, 10) are torsion bars (7, 9), specifically first torsion bars (7) and second torsion bars (9) and the joining elements (11, 12) are bending elements (11). The second torsion bar (9) further from the base (2) is linked to an upper area of the vertical frame (19) of the supporting structure (1) and the other second bar (9) is linked to the vertical frame (19) in the area closest to the base (2).
The first torsion bars (7) are joined directly to the mobile structure (3) and the second torsion bars (9) directly to the supporting structure (1), by means of clamps (15) which are joined to the torsion bars (7, 9) through a central area of the latter, the torsion bars (7, 9) being retained in the clamps (15). As seen in the profile view, the distance between the first torsion bars (7) is smaller than the distance between the second torsion bars (9). This configuration is especially suitable when the extraction of the product in solidification follows a curved trajectory, while for tables with a vertical trajectory the first torsion bars (7) and the second torsion bars (9) have the same distance.
The rigidity of the bending elements (11) in the embodiment shown is the same, being able to be different in another alternative embodiment. The first torsion bars (7) are arranged in a front area of the oscillating table and the second torsion bars (9) are arranged in a rear area of the oscillating table such that the mobile structure (3) and the cavity (4) thereof are arranged between them, the pairs being arranged equidistant with respect to the first direction (X).
Specifically, in the embodiment shown, a single actuating element (6) is shown facing the first torsion bars (7), which is responsible for generating the movement of the mobile structure (3). Preferably, the actuating element (6), which is a hydraulic or electromechanical cylinder, is equipped with a bending bar (24) like the one shown in the figures.
The table further comprises connecting parts (21) intended to be connected to a cooling system. The oscillating table comprises a pair of damping elements (13, 14) on each side of a longitudinal axle of the mobile structure (3), linked to the base (2) and to the mobile structure (3), which are pneumatic supports (13).
The oscillating table comprises a pair of damping elements (13, 14), which in the embodiment shown are pneumatic supports (14), one on each side of the longitudinal axle of the mobile structure (3) and which are linked to the base (2) and to the mobile structure (3).
The table of the embodiment shown comprises a single actuating element (6) facing the first torsion tubes. The torsion tubes (8, 10) comprise helical slots (22) extending from the proximities of the ends thereof which enable a partial torsion of the torsion tubes (8, 10).
The oscillating table comprises first torsion bars (7) joined to the mobile structure (3) through the bending elements (11). The torsion bars (7, 9) are retained by means of clamps (15) directly joined to the vertical frames (19) of the supporting structure (1), wherein the first torsion bars (7) are joined to the mobile structure (3) through the bending elements (11). Specifically, the oscillating table comprises two pairs of bending elements (11) on each side, which are joined at one end to the mobile structure (3) and at the other end to torsion bars (7, 9).
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/ES2021/070423 | 6/9/2021 | WO |
