EP0876230A1

EP0876230A1 - Oscillator for continuous casting die

Info

Publication number: EP0876230A1
Application number: EP97902164A
Authority: EP
Inventors: Emile Lonardi; Hubert Stomp; Rudy Petry; Norbert Kaell; André Kremer; Radomir Andonov
Original assignee: Paul Wurth SA
Current assignee: Paul Wurth SA
Priority date: 1996-01-18
Filing date: 1997-01-09
Publication date: 1998-11-11
Anticipated expiration: 2017-01-09
Also published as: DE59700687D1; US6167940B1; ES2138856T3; AU1591797A; DK0876230T3; WO1997026099A1; ATE186485T1; EP0876230B1; LU88702A1

Abstract

The patent describes an oscillating device for a continuous casting mould with a supporting structure (10), an oscillating lever (12), which has a forked first lever arm (30) and a second opposing lever arm (32), this oscillating lever (12) being mounted in the supporting structure by means of first swivel joints (26', 26'') so as to be vibratable about an axis (28), and a stroke generator (14), which is connected to the second lever arm (32) of the oscillating lever (12). The oscillating device according to the invention comprises a supporting cage (18) for suspension of a continuous casting mould (20), this supporting cage (18) being connected via second swivel joints (40', 40'') to the forked first lever arm (30) of the oscillating lever (12).

Description

Vibrating device for continuous casting mold.

The invention relates to a vibrating device for a continuous casting mold, in particular for the continuous casting of steel.

When continuously casting steel strands, the molds are oscillated in the casting direction in order to prevent the strand from sticking to the cooled inner walls of the pouring tube. These vibrations of the mold can, for example, have a frequency of a few Hertz and an amplitude of more than 10 mm, the vibrating mass making up several tons. The oscillation of the mold therefore requires a very high level of performance. From this it follows that it is desirable to keep the vibrating mass as small as possible.

A classic vibrating device comprises a lifting table on which the continuous casting mold is arranged as a unit. These lift tables have a relatively large mass and also require a lot of space below the mold, where this space is not always available.

The international patent application WO 95/03904 describes a mold which has a fixed housing to which a pouring tube is connected via two elastically deformable, annular sealing membranes in such a way that it can vibrate in the housing along the pouring axis. The annular sealing membranes seal an annular pressure chamber for a cooling liquid around the pouring tube. At its upper end, the pouring tube comprises lateral bearing journals with which it is suspended in a rocker arm. The latter is rotatably mounted in the housing about a horizontal axis. A lever arm is sealed out of the pressure chamber and connected to a lifting cylinder that generates the vibrations. With this mold, the mass of the parts to be oscillated and thus the effort required are greatly reduced. A disadvantage of this mold is that the replacement of the pouring tube is relatively complex since the ring-shaped sealing membranes first have to be dismantled. The international patent application WO 95/05910 describes a compact vibrating device which has an annular lifting cylinder has, in which a mold, ^' consisting of a pouring tube and a cooler, can be axially suspended. The cooling box of the mold is connected to a cooling water circuit via flexible pipe connections. The mold can be installed and removed relatively easily from this oscillating device, but the oscillating device is relatively complex in construction due to the annular lifting cylinder, in particular for molds with a large cross section.

The object of the present application is to create a compact and simple oscillating device in which the continuous casting mold can be installed and removed relatively easily. This object is achieved by a vibrating device according to claim 1.

An oscillation device according to the invention comprises a support structure, an oscillation lever which has a fork-shaped first lever arm and a second opposite lever arm, this oscillation lever being mounted in the support structure such that it can be pivoted about an axis by means of first rotary joints, a stroke generator which is connected to a second lever arm of the oscillation lever, and a support cage for hanging a continuous casting coke, which support cage is connected to the fork-shaped first lever arm of the rocking lever via second swivel joints. The continuous casting mold therefore only needs to be hung in the support cage attached to the rocker arm and is therefore particularly easy to install and remove. The rocker arm with support cage is a simple construction that can be adapted to molds with a large cross-section with reasonable effort and takes up little or no space below the mold. The weight of the continuous casting mold can be largely compensated for by a counterweight on the second lever arm of the rocking lever, so that the stroke generator does not have to work against the total weight of the continuous casting mold and can therefore be designed to be relatively small.

The oscillating device advantageously comprises at least one guide member which is connected to the support structure via a first swivel joint and to the support cage via a second swivel joint. If the support cage with the inserted continuous casting mold is to oscillate along a circular arc-shaped center line of a casting strand which is curved in the form of an arc, the axes of the Swivel joints are perpendicular to a plane in which the circular arc-shaped center line is contained, in which plane a first straight line intersects the axes of the swivel joints between the rocker arm and support cage and rocker arm and support structure, and a second straight line the axes of the swivel joints between the guide member and support cage and guide member and Carrier structure intersects, and these axes are in such a way that the first straight line and the second straight line intersect approximately in the center of curvature of the circular arc-shaped center line of the casting strand. If the support cage should always remain parallel to itself when swinging, the axes of the swivel joints must be in such a way that the predefined first and second straight lines are parallel to one another.

In the known vibrating devices, flexible hose connections or relatively long pipe compensators were used to supply the vibrating continuous casting mold with a cooling liquid. Flexible hose connections or pipe compensators in the area of the continuous casting device are now not without problems. Due to the high temperatures and metal splashes, they are always exposed to the risk of damage. Furthermore, they require quite a lot of space and only tolerate the vibration stresses poorly. In order to replace flexible hose connections and pipe compensators, the rocker arm and / or the guide members each have at least one channel for a cooling liquid, which opens via a first swivel connection, in one of the first swivel joints, into a pipe socket that is fixed relative to the support structure, and the via a second swivel joint, in one of the second swivel joints, opens into a pipe socket that is fixed relative to the support cage. A flow or return line of an external cooling circuit can be rigidly connected to the pipe socket, which is fixed relative to the supporting structure. On the other hand, a supply or return line of an inner cooling circuit of a continuous casting mold can be rigidly connected to the pipe socket which is fixed relative to the support cage. The support cage advantageously comprises a lower and upper U-shaped frame which are advantageously rigidly connected to one another. In this rigid support cage is the continuous casting mold can be inserted laterally, the lower and the upper U-shaped frame each being closable by a crossbar.

The support cage advantageously comprises lateral pressure means for centering the continuous casting mold in the casting axis without play. The invention also relates to a continuous casting device with a vibrating device as described above. Such a continuous casting device has, for example, a continuous casting mold with at least one upper collector, which is designed as a support to match the upper U-shaped frame.

The continuous casting mold can be designed as a tubular mold or can be composed of molded plates. If the continuous casting mold is composed of shaped plates, the support cage improves its mechanical stability.

The aforementioned mold plates each advantageously have a box-shaped upper and lower collector, which are arranged such that when the continuous casting mold is mounted in the support cage, the upper collector of the mold plate rests on the upper U-shaped frame, and the lower collector the lower U-shaped frame reaches under. The lower and upper collectors advantageously each have at least one cooling liquid connection and are connected to one another by cooling channels in the molding plate. In order to ensure a uniform flow against these cooling channels, the lower and upper collectors each have a cross-sectional constriction between the cooling liquid connection and the mouths of the cooling channels.

If a continuous casting mold comprises a plurality of coolant supply or return connections, it advantageously surrounds at least one supply or return ring line. These ring lines are connected via at least one, essentially rigid pipe connection to at least one of the pipe sockets which are fixed relative to the support cage, and are connected via spur lines to the flow or return connections of the continuous casting mold.

Exemplary embodiments of the invention are explained with reference to the attached drawings. Show it: FIG. 1: a perspective view of a vibrating device according to the invention with an expanded continuous casting mold and an open support cage;

Figure 2 is a schematic representation of the vibrating device as a gear; 3 shows a longitudinal section through a continuous casting mold in the support cage of a vibrating device according to the invention, the continuous casting mold being connected to a cooling circuit via rocker arms and guide members;

FIG. 4: a cross section through a continuous casting mold similar to that in FIG. 3, the rocker arm and its swivel joints also being partially cut;

5 shows a plan view of the continuous casting apparatus of FIG. 3.

The oscillation device in FIG. 1 essentially consists of a support structure 10 (shown in dashed lines), an oscillation lever 12, a stroke generator 14, two guide members 16 'and 16 "and a support cage 18 for a continuous casting mold 20 (shown here in the removed state).

In an advantageous embodiment, the support structure 10 consists of a cylindrical housing 22 and a mounting plate 24. The rocking lever 12 is fastened in the housing by means of two swivel joints 26 ', 26 "in such a way that it can swing about a substantially horizontal axis 28. It comprises one first, fork-shaped lever arm 30, and a second, opposite, one-piece lever arm 32. The stroke generator 14, which is advantageously designed as a hydraulic lifting cylinder, is connected in an articulated manner to the second lever arm 32. This lifting cylinder 14 is also articulated with a housing flange 34 is connected and supported by the latter on the support structure 10. The two guide members 16 ', 16 "are likewise fastened in the housing by means of two swivel joints 26', 26" in such a way that they are both about an essentially horizontal axis 38 can swing.

The support cage 18 is connected to the rocker arm 12 via pivot joints 40 ', 40 "(only the pivot joint 40" is visible in FIG. 1) such that

Rocker arm 12 and support cage 18 about an axis 42 relative to each other are rotatable. The support cage 18 is also connected via pivot joints 44 ', 44 "(only the pivot joint 44" is visible in FIG. 1) to the guide members 16', 16 "in such a way that the guide members 16 ', 16" and the support cage 18 are relative about an axis 46 are rotatable to each other. In Figure 2, the vibrating device is shown in a highly simplified manner as a gear, the aforementioned axes of rotation 28, 38, 42 and 46 are all perpendicular to the plane of Figure 2 and are therefore shown as points. The supporting structure 10, which surrounds the supporting cage as the outer housing, is indicated as fixed points 10 ', 10 "and 10'". The individual movable members of the transmission are the rocker arm 12, with its two arms 30 and 32, the guide members 16 ', 16 ", and the support cage 18. The reference number 19 shows a counterweight. Such a counterweight can be on the second lever arm 32 are attached in order to compensate for the moment of weight of the support cage 18 with inserted mold 20 acting on the lever 30. The drive of the transmission is shown as a lifting cylinder 14. G1 denotes a straight line which is defined by points 28, 42, while G2 is a straight line which is defined by points 38, 42. These straight lines G1 and G2 intersect at a point "0" which approximately corresponds to the center of an arc 50 which represents the center line of an arc-shaped casting strand. In practice, the radius of such an arc-shaped casting strand is for example about 10 m. If the lifting cylinder 14 is actuated, the support cage 18 swings, in the case of small Schwingu ngs amplitudes (in the order of magnitude of about 10 mm), in a first approximation tangential to the circular arc 50. In other words, the inclination of the support cage 18 relative to the vertical changes like the inclination of the tangent to the circular arc 50. On the other hand, the lines G1 and G2 parallel to each other, the vibrating support cage 18 would always remain parallel to itself, that is, remain vertical in the embodiment shown.

In Figure 1 it can be seen that the support cage essentially comprises an upper U-frame 50 and a lower U-frame 52. Both U-frames are rigidly connected to one another via vertical profiles 54. The upper U frame

50 serves as a support for a collar-shaped support 60 of the continuous casting mold le 20. As indicated in Figure 1, the continuous casting mold 20 is inserted laterally into the support cage 18. The lower U-frame 52 is advantageously gripped by a collar-shaped lower border 62 of the continuous casting mold 20. After the continuous casting mold 20 is suspended in the support cage 18, the two U-frames 50 and 52 are closed by crossbeams 50 ', 52'. Pressing means, for example screws 56, are advantageously arranged on all four sides of the support cage 18 in such a way that they are supported on the one hand on the support cage and on the other hand on the continuous casting mold 20 in order to enable play-free centering of the continuous casting mold 20 in the supporting cage 18. The continuous casting mold 18 can be designed as a tubular or plate mold for casting a wide variety of products, such as billets, pre-profiles (beam blanks), slabs, thin slabs, etc. A particularly advantageous embodiment of a plate mold for the oscillating device is shown in the figures. This plate mold is composed of four shaped plates 64 which form a pouring channel with an essentially rectangular or square cross section. FIG. 3 shows a longitudinal section through two of these shaped plates 64. Such a molding plate 64 each includes an upper and lower box-shaped collector 66 and 68, which are designed such that they form the upper collar-shaped support 60 or the lower collar-shaped border 62 of the continuous casting mold 20 in the assembled mold. Each of the collectors 66 and 68 has a connection 66 'or 68' for a coolant line. The coolant flows, for example, through the connection 68 ′ into the lower collector 68. Here it is introduced through a cross-sectional constriction 68 "into cooling channels 70. The latter pass through the body 72 of the molding plate 64, which can be made of pure copper or a copper alloy, for example, before they open into the upper collector 66 via a cross-sectional constriction 66" . The cooling channels 70 are arranged in the body 72 of the mold plate 64 in such a way that a perfect cooling of the surface 74 of the mold plate 64 in the pouring channel is ensured. In the lateral mold plates of the mold according to FIG. 4 (ie in the mold plates which laterally form a flat cooling surface in the pouring channel), the cooling channels 70 'are, for example, as Bores or cast channels in the body 72 of the molding plate 64 are performed. In the front and rear mold plate of the mold according to FIG. 4 (ie in the two mold plates which advantageously form a curved cooling surface which corresponds to the curvature of the casting strand), the cooling channels 70 "are advantageously milled into the body 72 and closed with a welded-on plate 71 The milled cooling channels 70 "lie at a constant distance behind the curved cooling surface. Of course, a gap-shaped cooling space can also be arranged behind the cooling surface, which is then advantageously divided into cooling channels by ribs. In this case, the mold plate, like a sandwich, is advantageously composed of two halves.

The continuous casting mold suspended in the support cage could of course, as is known, be supplied with a cooling liquid via flexible lines. 4 and 5, however, a far more advantageous solution for supplying the continuous casting mold with a cooling liquid in an oscillating device according to the invention is described. According to this solution, the continuous casting mold is supplied with a cooling liquid via the four swivel joints 26 ', 26 ", 40', 40" and the two arms 30 ', 30 "of the rocker arm 12. For this purpose, the swivel joint 26' comprises one cylindrical support pin 100, which is fixed in a rotationally fixed manner to the support structure 10 and has an axial blind bore 102. The support pin 100 is inserted into a bearing bore 104 of the rocker arm 12. In the bearing bore 104, the axial blind bore 102 forms a radial opening 106. Opposite the opening 106 forms a Channel 110 in arm 30 'of rocker arm 12 also has an orifice 112. Both orifices 106 and 112 are designed such that when the rocker arm 12 rotates around the support pin 100, they always overlap sufficiently to ensure that the cooling medium passes over smoothly -Rings 108 or other sealing means, the radial play of the trunnion 100 in the bearing bore 104 is axial The hinge 40 "is constructed similarly. A cylindrical support pin 120, which has an axial blind bore 122, is connected in a rotationally fixed manner to the support cage 18. This support pin 120 is in a bearing bore 124 of the arm 30 ' of the rocker arm 12 introduced. As described above, blind bores 122 are connected to the channel 110 in the arm 30 'of the rocker arm 12 via openings which overlap in the bearing bore 124.

The coolant can now be introduced into the axial bore 102 via a pipe socket (schematically indicated by arrow 103) which is fixedly connected to the fixed bearing journal 102. From here it can pass into the channel 110, pass through this channel 110 into the swivel joint 40 ', pass into the blind bore 122 of the pivot 120 here and flow through the blind hole 122 into a pipe connection 130' which is firmly connected to the pivot 102 . This pipe connection 130 'which can be oscillated with the support cage 18 opens into a ring line 132 which is connected by stub lines 134 (see FIG. 5) to the individual connections 68' of the lower collector 68 of the continuous casting mold.

The second arm 30 "of the rocker arm 12, with the swivel joints 26" and 40 ", can then, as shown in FIG. 4, be designed as a connection of the upper collector 66 of the continuous casting mold to a fixed return line for the cooling liquid (indicated schematically by arrow 105) For this purpose, a second ring line 136 is connected via branch lines 134 (see FIG. 5) to the individual connections 66 'of the upper collector 66 of the continuous casting mold 20. A rigid pipe connection 130 "rigidly connects this second ring line 136" to the pivot pin of the swivel joint 40 "on (the second ring line 136 can thus also be oscillated with the mold 20. The coolant passes from the swivel joint 40" into the second lever arm 30 "and passes via this into the swivel joint 26", where it enters the fixed return line 105.

Alternatively, both arms 30 'and 30 "of the rocker arm 12 can also be used for the supply of the cooling liquid. In this case, the two guide members 16', 16" with their swivel joints 36 ', 36 ", 44', 44", as in FIG. 3 indicated, advantageously designed as a return connection for the coolant. It remains to be noted that for easier installation of an electromagnetic stirrer (not shown), the rocker arm 12 is advantageously connected to the lower end of the support cage 18, and the guide members 16 ', 16 "are advantageously connected to the upper end of the support cage 18 The guide members 16 ', 16 "can then advantageously be folded up out of the support structure 10, so that the toroidal coil of the electromagnetic stirrer can simply be inserted from above, without the rocker arm 12, the guide members 16', 16" or the support cage 18 to dismantle.

Claims

PATENT CLAIMS

1. Swinging device for a continuous casting mold comprising a supporting structure (10), a rocker arm (12) which has a fork-shaped first lever arm (30) and a second lever arm (32) located opposite, said rocker arm (12) by means of first rotary joints (26 ', 26 ") is mounted in the support structure so as to be oscillatable about an axis (28), a lift generator (14) which is connected to the second lever arm (32) of the oscillating lever (12), characterized by a support cage (18) for hanging a strand Casting mold (20), said support cage (18) being connected to the fork-shaped first lever arm (30) of the rocking lever (12) via second swivel joints (40 ', 40 ").

2. Vibration device according to claim 1, characterized by at least one guide member (16 ', 16 ") via a first swivel joint (36', 36") with the support structure (10) and via a second swivel joint (44 ', 44 ") the support cage (18) is connected.

3. Vibration device according to claim 2, characterized in that the support structure is designed as a housing (10) which surrounds the support cage (18).

4. Vibration device according to claim 2, characterized in that the axes of the pivot joints are perpendicular to a plane in which the circular arc-shaped center line (50) of a circular arc-shaped casting strand is contained, in which plane a first straight line (G1) Axes (28, 42) of the swivel joints between the rocker arm (12) and support cage (18) and rocker arm (12) and support structure (10) intersect, and a second straight line (G2) the axes (38, 46) of the swivel joints between the guide ¬ approximately (16 ', 16 ") and support cage (18) and guide member (16', 16") and support structure (10) intersects, and these axes (28, 38, 42, 46) are such that the first straight line (G1) and the second straight line (G2) cut approximately in the center of curvature (O) of the arcuate center (50) of the casting strand.

5. Swinging device according to claim 1, characterized in that the rocker arm (12) has at least one channel (110) for a cooling liquid, which via a first pivot connection, in one of the first

Swivel joints (26 ', 26 "), into a pipe socket (103) which is fixed relative to the support structure (10), and which via a second swivel joint, in one of the second swivel joints (40', 40"), into a relative to the Support cage (18) fixed pipe connection (130) opens.

6. Vibration device according to claim 2, characterized in that the guide member (16 ', 16 ") has at least one channel for a cooling liquid which, via a first swivel connection, in the first swivel joint (36', 36"), in one pipe socket fixed relative to the support structure, and which opens via a second swivel connection, in the second swivel joint (44 ', 44 "), into a pipe connection (130) fixed relative to the support cage (18).

7. Vibration device according to one of claims 1 to 6, characterized gekenn¬ characterized in that the support cage (18) comprises a lower and upper U-shaped frame (50, 52).

8. Vibrating device according to claim 7, characterized in that the lower and the upper U-shaped frame (50, 52) are each closable by a transverse beam (50 ', 52').

9. Vibration device according to claim 7 or 8, characterized in that the lower and the upper U-shaped frame (50, 52) are rigidly connected to one another.

10. Continuous casting device with a vibrating device according to claim 7, 8 or 9, characterized by a continuous casting mold (20) which has at least one upper collector (60) which is designed as a support for the upper U-shaped frame (50).

11. Continuous casting apparatus according to claim 10, characterized in that the continuous casting mold is composed of shaped plates (64).

12. Continuous casting apparatus according to claim 11, characterized in that at least one mold plate (64) has a box-shaped upper and lower collector (66, 68) which are arranged such that in the continuous casting cage (20) mounted in the supporting cage (18), the upper collector (66) rests on the upper U-shaped frame (50), and the lower collector (68) engages under the lower U-shaped frame (52).

13. Continuous casting device according to claim 12, characterized in that the lower and upper collector (66, 68) each have a cooling liquid connection

(66 ', 68') and the mold plate (64) has inner cooling channels (70) which connect the upper and lower collectors (66, 68) to one another.

14. Continuous casting device according to claim 13, characterized in that the lower and upper collectors (66, 68) each between the cooling liquid connection (66 ', 68') and mouths of the inner cooling channels (70) one

Cross-sectional constriction (66 ", 68").

15. Continuous casting device with a vibrating device according to claim 5 or 6, characterized by a continuous casting mold with at least one obe¬ ren and / or a lower collector (66, 68) which via at least one substantially rigid pipe (134, 136) to one of the relative to

Support cage (18) fixed pipe connections (130 ', 130 ") is connected.

16. Continuous casting apparatus according to claim 15, characterized by a continuous casting mold with a plurality of cooling water flow connections (68 '), by means of a flow ring line (132) which is oscillatable with the mold (20) and which

Surrounds continuous casting mold and is rigidly connected to one of the pipe connections (130) which is fixed relative to the support cage (18), and by means of spur lines (134) which connect the flow ring line (132) to the cooling liquid flow connections (68 ').

17. Continuous casting apparatus according to claim 15 or 16, characterized by a continuous casting mold with a plurality of cooling liquid return connections (66 '), by a return ring line (136) which is oscillatable with the mold (20) and which surrounds the continuous casting mold and to at least one of the rela- pipe connections (130 ') which are fixed to the support cage (18) are rigidly connected, and by spur lines (134) which connect the return ring line (136) to the coolant return connections (68').

18. Continuous casting device according to one of claims 8 to 17, characterized by a continuous casting mold which by means of lateral pressing means (56) in

Support cage (18) is centered.