EP0537195B1 - Pouring tube insertion and replacement device - Google Patents

Abstract

A device (1) for inserting and replacing an insertable pouring tube (2) having a movable plate (3) and sliding on guide rails (9), which transmit thrust upwards, comprises a tilting member (20) which engages a lever (26) to impart a tilting motion to the movable plate (3) about a horizontal front edge thereof which engages a sealing area surrounding the pouring opening of a reference plate. This tilting motion makes the movable plate (3) completely parallel with the underside of the upper reference plate (6), improves the sealing contact between the two plates and prevents any infiltration of metal therebetween.

Description

The present invention relates to a device for supplying and exchanging a pouring tube for a metal pouring container from the bottom in which a movable closure plate and / or a replacement pouring tube attached to a movable plate is placed by a common transverse rim next to a movable plate carrying a pouring tube to be replaced or against a closure plate to be moved away from the tap hole, said movable replacement plate and that to be replaced being slidably mounted on guides capable of transmitting an upward thrust force and of guiding the translational movement of the plates and of the pouring tubes parallel to themselves under the action of a pneumatic cylinder in a direction perpendicular to the axis of the hole pouring, from a loading position to a service position in the axis of the container tap hole and from the service position to a release position, so as to per put the exchange of the tube without lifting the container.

It finds its main application in the steel industry in continuous casting installations for the placement in alignment of the axis of the tap hole of a metallurgical container, under the latter, interchangeable pour tubes.

The pouring tubes intended to lead the molten metal into a mold or a mold well, are wear parts which are highly stressed. They are so so that their service life limits the casting time.

Document EP-A-0192019 discloses a device for supplying and exchanging a pouring tube with a movable attached plate for a steel or metallurgical container which can be closed off at the bottom using a stopper or a sliding closure.

The supply and exchange device comprises a movable refractory plate capable of sliding, under the action of a jack, along an upper reference plate, from a loading position to a service position or a closed position in alignment with the axis of a tap hole.

Guide rails apply the movable plate, in sealed contact, against the upper reference plate under the effect of an upward thrust transmitted by a first end of levers on which act downwards at an opposite end of the helical springs taking support on the frame of the supply and exchange device.

The guide rails are parallel to each other and form a slightly inclined plane at an angle of 5 to 10 ° relative to the reference plane. Such a device makes it easy to replace a pouring tube with a movable refractory insert without raising the distributor.

A double pneumatic cylinder ensures the linear movement of the movable plate carrying the pouring tube. The replacement tube is brought by pivoting around a substantially horizontal axis in the mold or the mold well in order to allow the exchange of pouring tube without having to lift the distributor.

In this known device, the movable plate intended to slide along a rectilinear trajectory along the upper reference plate forms with respect to the latter an inclined surface whose inclination is determined by the slope of the trajectory of the guide rails.

The inclination of the guide rails relative to the reference plane of the upper plate makes it possible to obtain a progressive tightening of the movable plate attached to the pouring tube when the latter is brought into alignment with the pouring orifice. but has the drawback of making the junction of the two plates not leaktight in the vicinity of the pouring orifice. In fact, the parallelism of the bottom plate and of the movable plate carrying the pouring tube is not perfect during the engagement of the movable plate in the sealing zone surrounding the pouring orifice. Liquid metal can seep between the upper reference plate and the movable plate. Upon hardening, the infiltrated metal forms a crust which alters the flatness of the contact surfaces and risks causing the movable plate to jam and being a cause of non-sealing of a contact zone of the two plates in the immediate vicinity of the pouring orifice.

The present invention aims to overcome this drawback and proposes for this purpose a device which ensures the parallelism of the replacement movable plate with the upper reference plate, as soon as the tap hole is covered by said movable plate brought into the immediate vicinity of the pouring orifice by a pneumatic cylinder.

The device for supplying and exchanging a pouring tube is of the type described in the first paragraph of this specification. This device is characterized in that it comprises means for imparting to the movable plate a tilting movement around a frontal horizontal edge of the movable plate engaged in the area adjacent to the pouring orifice, so as to make the movable plate strictly parallel to the underside of the upper plate. This tilting movement makes possible the sealed contact of the movable plate against the upper plate and prevents any leakage of liquid metal during the exchange of the pouring tube or when the pouring orifice is closed by a movable plate d shutter.

According to a feature of the invention, the means intended to give the movable plate a tilting movement consist of a lever acting upwards on a rear part of the movable plate opposite the front edge engaged in the sealing zone surrounding the pouring hole of the reference plate.

In a first particular embodiment of the invention, the lever is a portion of guide rail fixed by an end remote from the taphole to a rocker arm comprising, a crank articulated around a horizontal shaft, against which a piston pushed back by a helical spring as soon as the piston is released by a double pneumatic cylinder intended to slide a movable plate along the guide rails.

In a second particular embodiment of the invention, the rocker arm comprises a first arm fixed in a direction normal to the surface of a cylindrical ring mounted on a horizontal shaft around which is wound a torsion spring fixed by a first end in the ring and by a second end in a fixed frame of the supply device, the ring being displaced angularly around the shaft against the spring under the action of the thrust exerted by the double jack on a second arm s 'extending perpendicular to the first arm in a radial plane of the cylindrical ring.

These features and details of the invention as well as others will become apparent during the following detailed description in which reference is made to the accompanying drawings. These drawings illustrate two embodiments of the invention, given by way of illustrative and nonlimiting examples.

• la figure 1 est une vue en bout d'un dispositif d'amenée et d'échange selon l'invention d'un tube de coulée disposé sous un récipient de coulée;
• la figure 2 est une vue en élévation latérale a plus grande échelle du dispositif d'amenée et d'échange montré dans la figure 1 présentant un rail-guide en position de chargement;
• la figure 3 est une vue en élévation latérale analogue à celle de la figure 2 comprenant un rail-guide en position relevée;
• la figure 4 est une vue du dessous du dispositif d'amenée montré dans la figure 3;
• la figure 5 est une vue en perspective avec arrachement partiel, du dispositif d'amenée et d'échange montré dans la figure 2, muni d'une première forme de réalisation d'un culbuteur selon l'invention, montré en position basse d'attente;
• la figure 6 est une vue en perspective du dispositif montré dans la figure 1, le culbuteur ayant actionné le rail-guide en position relevée;
• la figure 7 est une vue éclatée en perspective d'une seconde forme de réalisation d'un culbuteur selon l'invention;
• la figure 8 est une vue en perspective partiellement arrachée du culbuteur montré a la figure 5, occupant une position basse; et
• la figure 9 est une vue en perspective semblable à celle de la figure 6, montrant le culbuteur en position relevée.

In these drawings:

• Figure 1 is an end view of a supply and exchange device according to the invention of a pouring tube disposed under a pouring container;
• Figure 2 is a side elevational view on a larger scale of the supply and exchange device shown in Figure 1 having a guide rail in the loading position;
• Figure 3 is a side elevation view similar to that of Figure 2 comprising a guide rail in the raised position;
• Figure 4 is a bottom view of the feed device shown in Figure 3;
• Figure 5 is a perspective view with partial cutaway, of the supply and exchange device shown in Figure 2, provided with a first embodiment of a rocker arm according to the invention, shown in the lower position of waiting;
• Figure 6 is a perspective view of the device shown in Figure 1, the rocker having actuated the guide rail in the raised position;
• Figure 7 is an exploded perspective view of a second embodiment of a rocker arm according to the invention;
• Figure 8 is a partially cutaway perspective view of the rocker arm shown in Figure 5, occupying a low position; and
• Figure 9 is a perspective view similar to that of Figure 6, showing the rocker arm in the raised position.

In these figures, the same reference notations designate identical or analogous elements.

FIG. 1 shows a device for supplying and exchanging a pouring tube according to the invention, generally designated by the reference sign 1, mounted under a tapping distributor 5 in the vicinity of the tapping hole 7.

The distributor can possibly already be fitted with a sliding closing device. Generally the shutter is simply a stopper (not shown). The device 1 is intended to allow the supply of a reserve pouring tube 2 attached to a movable plate 3, in the loading position 14, and the replacement of a worn tube 2 ', attached to a movable plate 3' , in service position 14 '. (Figure 2)

The pouring tubes 2, 2 ', each attached to a movable plate 3, 3', slide along an upper reference plate 6 applied under the flow distributor 5, against an internal nozzle 39 held in place by a brick of seat 18. The seal between the internal nozzle 39 and the reference plate is ensured by a sealing collar 19.

The upper reference plate 6 is optionally formed of several independent refractory elements. The refractory element surrounding the taphole is optionally provided, on a lower face, around a pouring orifice 27, with a groove 40 connected to a duct 41 for supplying argon.

Two guide rails 9 have an inclined stroke relative to the reference plate 6.

In a manner known per se, as described in document EP-A-0192019, the guide rails 9 are divided into two fixed rail sections 9 ′ secured to a frame intended to be mounted under the tundish 5 in the vicinity of the tap hole 7 and three movable rail sections 9 '' and arranged between the two respective fixed rail sections in their mutual extension.

The sections of movable guide rails 9 '' are each mounted at the end of a lever pivoting about an axis AA '. Each lever is subjected at its opposite end to the action of a spring 10 which, by pushing this opposite end down, applies the movable rail sections upwards.

The force exerted by the movable guide rails 9 '' on each of the movable plates associated with the pouring tube 2 moving along said fixed guide rails 9 'and movable 9' 'increases as said plates come closer tap hole 7.

The slope of the guide rails 9 makes it possible to obtain a progressive tightening of the movable plate 3 of a pouring tube 2 against the upper reference plate 6 when any of the pouring tubes 2, 2 'is close to the taphole 7. This tightening decreases when the movable plate 3 moves away from it, allowing easy removal of the above-mentioned plate in the release position 17 on the other side of the taphole 7.

When the movable plate 3 engages in the sealing zone surrounding the tap hole 7, the movable plate 3 rests on the guide rails 9 and has a relatively small inclination relative to the upper reference plate 6 but sufficient to cause liquid metal to infiltrate between the upper reference plate 6 and the movable plate 3.

The movable plate 3, however applied upwards against the upper reference plate 6, under the thrust of levers 12, 12 'each subjected to the action of springs 10, 10' mounted at a sufficient distance from the tap hole 7, to protect them from the intense heat of the molten metal, does not ensure a perfect seal until the parallelism of the movable plate 3 with the upper reference plate 6 is not ensured.

It is only at the end of the supply and loading operation of the pouring tube 2 that the parallelism of the plates is perfect and that the force exerted by the guide rails 9 on the movable plate attached to the pouring tube 2 ', moving along said rails 9 is sufficient since it increases as the movable plates approach the tap hole 7. This upward push does not seal the movable plates 3' and 3 of the used pouring tube 2 ′ and of the reserve tube 2 against the sliding plane of the reference plate 6, when the orifice formed in the movable plate 3 ′ is in alignment with the axis LL 'of tap hole 7 (Figure 3).

As illustrated in FIG. 4, the linear displacement of the mobile plates 3, 3 ′ is ensured by a retractable push rod 15 actuated by a pair of pneumatic cylinders 16, 16 ′ arranged in parallel in order to provide the force necessary to allow loading. casting tube 2 quickly, making the best use of the small space available in height. The rods 11 and 11 'of the cylinders 16 and 16' are interconnected by a movable frame 13 carrying the retractable push rod 15.

The purpose of the device according to the invention is to ensure parallelism between the movable plate 3 and the upper reference plate 6 from the start of the operation of supplying and loading the reserve pouring tube 2.

For this purpose, the device according to the invention comprises a rocker arm 20. The rocker arm 20 comprises a frame 21 fixed to the frame 4 of the device for feeding and loading the pouring tube, in the extension of one of the thrust cylinders 16 , 16 ', preferably, of the jack 16' closest to the guide rails 9 of the supply device.

The frame 21 houses a cylindrical housing 22 in which is housed a helical spring 23 compressed under the action of a piston head 24 subjected to the thrust of the movable frame 13 which connects the rods of the double pneumatic cylinder 16, 16 'intended to slide a movable plate 3 along the guide rails from the loading position 14 to the service position 14 '.

Before introducing a new pouring tube 2 into the supply and loading device, the double thrust cylinder 16, 16 'brought into the extended position, moves the movable frame 13 which comes to bear against the head of the piston 24 of the rocker arm 20. The head of the piston 24 of the rocker arm 20 compresses the helical spring 23 in the housing 22 and allows a crankset 38 coupled to a bent lever 26 to pivot about a horizontal axis HH 'and to lower the lever 26 to a loading position in the extension of the slight slope of the guide rails 9. The retractable pusher arm 15 is removed and a new pouring tube 2 placed on the guide rails 9 (Figure 5). The new pouring tube is then placed in the loading position 14 and the retractable pusher arm 15 is released from the movable frame 13.

When the tube is brought from the loading position 14 to the service position 14 'in the axis of the tap hole 7, under the action of the double jack 16, 16', the movable frame 13 s' away from the rocker arm 20 and releases the piston rod 24 from the rocker arm 20. The piston rod 24 is pushed back by the helical spring 23 against an abutment screw 36 of the lever 26 which pivots a fraction of a turn around the horizontal shaft HH 'of the rocker arm 20 so as to raise the bent lever 26 upwards (Figure 6)

The raising of the bent lever 26 gives the movable plate a tilting movement around a horizontal front edge of the movable plate introduced into the sealing zone surrounding the pouring orifice 27. This tilting movement makes the movable plate 3 strictly parallel to the underside of the upper reference plate 6, (Figure 6)

The device brings the movable plate 3 horizontally by raising the part of the movable plate furthest from the pouring orifice 27, immediately after having put in place the pouring tube 2 attached to the movable plate in the loading position 14, before or while the movable plate 3 slides towards a service position 14 'in alignment with the pouring axis LL' of the tap hole 7.

The tilting movement has the advantage of making it possible to apply the mobile plate 3 during translation under the action of the pneumatic cylinders 16, 16 ′, in leaktight manner against the upper reference plate 6 when changing the tube. It prevents any leakage of liquid metal between the movable plate 3 and the upper reference plate 6 at the start of the tube change operation.

A second embodiment of the device for feeding and loading a pouring tube 2 is shown in FIG. 7. It includes a rocker arm 20 comprising two arms 30 and 31: a first arm 30 is a lever extending in a direction normal to the surface of a cylindrical ring 32 and the second arm 31 is a tab extending in a direction tangent to the surface of the ring 32, that is to say in a radial plane of the ring 32 , and perpendicular to lever 30. The cylindrical housing 32 houses a torsion spring 33, the ends of which are anchored to the ring 32 and to the frame 4 of the supply device.

The movable frame 13 of the double pneumatic cylinder 16, 16 ′ pushes the first arm 30 down against the torsion spring 33 and returns, by pivoting around the shaft 34 in the direction of the arrow X, a lever 26 downwards, towards a position in which the introduction of a new pouring tube 2 is easy. The lever 26 is fixed on the shaft 34 using a screw 35. (Figure 8)

During the engagement of the new pouring tube 2 by linear displacement towards and in the sealing zone surrounding the pouring orifice 27 of the reference plate 6, the movable frame 13 of the double jack 16, 16 'moves away of the ring 32 and releases the first arm 30 which, under the action of the torsion spring, pivots at the same time as the second arm 31 and the lever 26 in the direction of the arrow Y. The pivoting movement of the second arm 31 is limited by the stop screw 36 (Figure 9). By pivoting, the lever 26 moves upwards a rear part of the movable plate 3, opposite to the front edge already engaged in the sealing zone surrounding the pouring orifice 27. This tilting movement of the movable plate 3 around its front horizontal edge, makes the plate 3 strictly parallel to the upper reference plate 6 and improves the seal between the contact surface portions of the two aforementioned plates.

Claims (6)

1. Device for the positioning and replacement (1) of a teeming tube (2) at the bottom of a vessel holding molten metal (5), in which a closing plate and/or a replacement teeming tube (2) associated with a movable plate (3) is placed by means of a common transverse edge against a movable plate (3') bearing a teeming tube (2') to be replaced or against a closing plate to be withdrawn from the teeming hole, the said movable replacement plate (3) and the one to be replaced (3') being mounted so as to slide on guide rails (9) suitable for transmitting an upward thrust and guiding the translational movement of the plates (3, 3') and of the teeming tubes (2, 2') parallel to each other by the action of a pressure cylinder (16, 16') in a direction at right angles to the teeming axis (L, L'), from a loading position towards an operating position in the axis (L, L') of the teeming hole (7) of the holding vessel (5) and from the operating position to a release position, so as to allow the replacement of the tube without raising the holding vessel (5), characterised in that it comprises a tilting device (20) which moves a lever (26) between a lower, loading position and a raised, operating position in such a way as to impart to the movable plate a tilting movement about a horizontal front edge of the movable plate engaging in the sealing zone surrounding a teeming opening (27) made in a reference plate (6), so as to make the movable plate (3) strictly parallel to the lower face of the upper reference plate (6).
2. Device in accordance with claim 1, characterised in that the tilting device (20) causes the lever (26) to pivot through a fraction of a turn, so that, in the operating position, the lever acts upwards on a rear part of the movable plate opposite to the front edge engaging in the sealing zone surrounding the teeming opening (27) in the reference plate (6).
3. Device in accordance with claim 1 or 2, characterised in that the lever (26) acts in the lower loading position in the extension of the guide rails (9).
4. Device in accordance with any one of the preceding claims, characterised in that the lever (26) is fixed at one end away from the teeming hole to a tilting device comprising a crank pin (38) articulated around a horizontal shaft (H, H'), the crank pin working in conjunction with a piston (24) which is forced back by a helical spring (23) as soon as the piston (24) is released by a movable frame (13) of the double pneumatic cylinder (16, 16'), the purpose of which is to cause a movable plate (3, 3') to slide along the guide rails (9).
5. Device in accordance with claim 1 or 2, characterised in that the tilting device (20) comprises a crank pin (38) connected to an elbow lever (26), the lever (26) being pivoted about a fixed horizontal shaft (H, H'), the said lever being actuated by the crank pin (38), which is moved at an angle through a fraction of a turn by the action of a double pneumatic cylinder (16, 16'), the purpose of which is to cause a movable plate (3) to slide along the guide rails (9) from an operating position, in which the lever (26) acts upwards on a rear part of the movable plate (3) opposite to the front edge engaging in a sealing zone surrounding the teeming opening (27), towards a lower position for loading a replacement tube (2) against a helical spring (23), which moves the lever (26) back to the operating position as soon as the lever (26) is released by the double cylinder (16, 16').
6. Device in accordance with claim 4, characterised in that the tilting device (20) comprises a first arm (30) fixed in a direction perpendicular to the surface of a cylindrical ring (32) fitted on a horizontal shaft, around which a torsion spring (33) is coiled, which is fixed at one end in the ring (32) and at the other end in the fixed structure (4) of the positioning device, the ring (32) being moved at an angle around the shaft against the torsion spring (33) by the thrust exerted by the movable frame (13) of the double cylinder (16, 16') on a second arm (31) extending at right angles to the above-mentioned lever (26) in a radial plane in relation to the cylindrical ring (32).

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