MXPA97004699A - Process for reuse of sliding gate plates and plate for this cie - Google Patents

Abstract

The present invention relates to a process for reusing the plates in a slide gate for a metallurgical vessel, the gate has a higher indentation and a lower indentation to receive a set of two refractory plates, each of these plates resting on an indentation per a face that becomes its support face and in cooperation with the other plate by a face that is transformed into its sliding face, the process characterized in that a set of refractories consisting of a new plate combined with a plate that has already been used once it is used in the sliding gate and in which, when the plates are changed a new plate is installed in a lower or higher loading indentation, this indentation remains the same in each plate change, the plate used only once is installed in the other indentation, which constitutes an indentation for the recycle

Description

PROCESS FOR REUSE OF SLIDING GATE PLATES AND PLATE FOR THIS CLOSURE The present invention relates to a process for reusing slide gate plates in a metallurgical vessel, especially a cauldron for making steel. It also refers to a plate for this closure and the closure itself. To control the flow of molten steel through the bottom of a metallurgical vessel, such as a steelmaker, a slide seal is generally used. This implies a fixed refractory plate in the upper part connected by means of a generally cemented connection to an internal nozzle located in the thickness of the refractory covering the wall of the lower part of the metallurgical vessel and a mobile lower plate connected to a collecting nozzle or an injection protection tube, also through a generally cemented connection.

These plates wear out quickly, so they need to be replaced frequently. To reduce the cost of refractories per ton of molten steel, it is known to use the same plates several times, possibly after cleaning or reconditioning.

For example, Stopinc GB 2, 625, 928 additionally describes a plate with two casting holes, ground on both sides and equipped with a metal belt. The plate is turned upside down and reused. However, a problem that occurs in common processes is human management. The operator does not know how many times the plates have been reused. The information must be stored; the history of the plates must be noted. This requires monitoring the plates, which is difficult. The efficiency of recycling is reduced. In addition, a plate that has been used has damaged areas, e.g., eroded and abraded areas. Its reuse introduces risks, for example, the infiltration of a metal between the two plates. The reuse of the plates, advantageous in the sense of the service life duration of the refractories, also implies the disadvantage of introducing risks.

The present invention proposes a process for reusing refractory plates for slide gate, the closure has an upper indentation and a lower indentation to receive a set of two refractory plates, and each of these plates resting on an indentation through a face that it becomes its supporting face and in cooperation with the other plate through a face that becomes its sliding face.

This process allows a simple handling of the plates and also allows to prolong the service life of the refractories reducing the risks associated with this extension.

The process is characterized by a set of refractories consisting of a new plate associated with a plate that has been used only once in the sliding closure and in which during the change of the plates, the new plate is installed in an indentation of lower or higher load, this indentation remains the same for each plate change, the plate used once installed in the other indentation (recycling).

This process thus defines a load indentation of the new plates, always the same, and an indentation of load of plates used only once, also always the same. In this way, the handling of the plates is simple. During a reconditioning of the slide gate operators know, in view of the indentation in which it was placed, which is used for the first time, which must be recycled and which plate has been used a second time and must be discarded.

The operator systematically discards the recycled plate and keeps the plate that has been used once in a suitable place, so that it can be recycled. Then, systematically install a new plate in the indentation of load, always the same, of the new plates and a plate recycled in the other indentation.

In addition, this process is very reliable. Indeed: - each plate is used two and only twice; - each side of the plate is used as a sliding face once and only once; - the sliding surfaces are systematically new; - two reused plates are not present at the same time in the slide fastener. In this way a set of two recycled plates is never used.

According to a preferred embodiment, the plate that is used once is placed in the indentation for recycling, so that the face that was its support face during the first application becomes its sliding face.

Depending on the mode of casting used, it may be of interest to install the new plate in the upper position or in the lower position.

According to one embodiment, the new plate is installed as the lower plate and the reused plate is the upper plate.

In this way, closing and regulation is always done with a new plate. The safety is optimal since the lower plate is important for the closing of the pouring hole. According to another embodiment, the new plate is used as a top plate. In this way, the union between the internal nozzle and the plate is made on new surfaces. The invention also relates to a refractory plate designed to be installed in an indentation of a sliding seal for a metallurgical vessel such as a cauldron or a funnel, this sliding closure has an indentation for the upper plate and an indentation for the lower plate. The plate is characterized in that it has an alignment device that can be installed only in a position in the upper indentation and in a single position in the lower indentation, so that the support face of the plate becomes its sliding face when the plate passes from one position to another.

Thus, when the recycled plate is installed one is sure that it is placed correctly, that is, in such a way that its supporting face becomes the sliding face and vice versa. On the other hand, one is not sure that the plate will be reused a second time in the same position. For this reason, the invention also relates to a plate characterized in that it has a means to prevent its installation a second time in the indentation reserved for the sliding gate plates, without preventing its installation in the indentation reserved for the recycled plates. In one embodiment, this means comprises an element capable of projecting outwards under the effect of the physical phenomenon originated by the spill of the molten metal,. for example, the temperature or expansion ends.

According to one embodiment, the means preventing installation more than once consists of a piece of deformed material with a state memory capable of recovering its original shape after being exposed to a certain temperature. According to another embodiment, the means preventing the installation of the plate more than once in an indentation consists of a mobile element seated in the plate and mechanically engaged, this hook being eliminated or destroyed during the introduction of a new plate in the indentation for the new plates, which causes the exit of the mobile element. For example, a fastener holds a piece of metal in a seat and acts on it by a spring when leaving this seat, expelling the fastener during the initial placement of the plate.

According to another embodiment, the means for preventing the installation of the plate more than once in an indentation of new plates is constituted by a deformation recorded on a part of the plate when it is inserted into the indentation of the new plates. For example, a tongue is rolled after the initial placement of the plate in the indentation of the new plates of the closure, the second indentation having a seat capable of receiving the tongue after it is wound. The plate is possibly ringed or has a metal wrap. In this case, its smallest face is at least equal to 60% of the other side. And it can have two or more pouring holes. The invention also relates to a sliding gate for a metal container having an indentation for an upper plate and an indentation for a lower plate, which is characterized in that these indentations have a shape that can not accept an upper plate and a plate. bottom, equipped with an alignment device in one position. The invention also relates to a slide gate having an indentation for an upper plate and an indentation for a lower plate, which is characterized in that only one of these indentations has a recess that allows the acceptance of a reused plate equipped with the means that prevents installation more than once in the same indentation of the slide gate. In this way, the operator is forced to install a new plate on the indentation that has no recess. The risk of using a plate used instead of a new plate is eliminated. In another variant of the invention, the plate has a double-position key, the first position of the key prevents the installation of the plate in an indentation of the new plates, obtaining the conduit of the key from the first position to the second by a remarkably thermal or mechanical effect or by a material with a shape memory. In this way one makes sure that the set of plates consists of a new plate and a plate used. Other features and advantages will be apparent upon reading the following description of the exemplified embodiments that are provided by means of the illustration with respect to the accompanying figures.

Figure 1 is a cross-sectional view of a slide gate and may be equipped with plates that conform the present invention.

Figures 2a, 2b and 2c present three stages of the process of the invention.

Figure 3 is a top view of a plate, according to the invention, having an alignment device. Figure 4 is a cross-sectional view of a plate according to the present invention and having a means to prevent installation more than once in the same indentation. Figure 5 is a top view of the plate shown in Figure 3 after initial use. Figure 6 shows the circulation of the plates. Figures 7 to 11 show different means of preventing the installation of a plate more than once.

Figure 1 shows a cross-sectional view of a slide gate for a metallurgical vessel, such as a steelmaker or distributor. The gate 2 is installed under a bottom wall 4 covered with a layer of refractory material 6. The slide gate has a fixed underframe 8 installed under the plate 4 and a door 10 which can be installed to rotate relative to the underframe fixed 8. A fixed upper plate 12 is installed in an indentation 14 of the upper part of the lower frame 8. A lower moving plate 16 is installed opposite the fixed plate 12. The plate 16 sits on an indentation 18 or a slide 20 The slide 20 can be moved in a known manner in relation to the fixed part of the slide gate to regulate or stop the flow of the molten metal. The upper fixed plate 12 is connected to an internal nozzle 13 which passes through the layer of refractory material 6 and has an axial channel for the passage of the molten metal. The movable lower plate 16 is connected to a collecting nozzle 21. The two plates are symmetrically identical. Each of the fixed plates 12 and mobile 16 have a circular hole 22 for the passage of molten metal. In the embodiment shown as example, plates 12 and 16 are ringed. In a variant, these plates could be surrounded by a metal casing in a known manner or they can not be ringed or have a metal casing. Plates 12 and 16 have identical flat faces. These faces do not distinguish themselves when they are not installed in the slide gate. On the other hand, when the plates have been placed in place, each has a supporting face with which it rests on the lower part of the indentation in which they are seated (upper indentation 14 or lower indentation 18). Likewise, each plate has a sliding face also called a working face. During the casting these working faces make it possible to regulate the flow of the metal. These are permanently rubbed together and wear out quickly. Consequently, it is necessary to change them often. According to the process of the invention, a new plate is systematically installed in the lower indentation 18 of the slide 20. After having been used once, the lower plate 16 is recovered and installed in the indentation 14 of the upper part of the lower frame 8. It is placed so that the face that was the working face when it was placed in the indentation 18 becomes its support face in the upper indentation 14. In a reciprocal manner, the face that was its supporting face It becomes your sliding or working face. This face is new in the sense that it had never been used as a sliding face. The portion of this surrounding the pouring hole was used to make a connection with the nozzle 21, but no wear occurred on the surface in question.

The top plate that had already been used once as the bottom plate is simply discarded. For the hole in the metal conduit 22 of the lower plate 16 to be located opposite the axial channel of the internal nozzle 13, it is necessary to rotate it 180 ° in the horizontal plane since the hole 22 is offset relative to the plate.

Figures 2a and 2b and 2c illustrate the successive steps of the reuse process according to the present invention. In figure 2a the plate A is the upper plate and the plate B is the lower plate before emptying the metal. The face of the plate A which has already been used is indicated by the scratch 24. This face serves as the support face in the indentation 14 (see FIG. 1). The other side of plate A constitutes its working face. This had never been used. Bottom plate B is new, none of its faces had been used. Figure 2b shows the plates A and B after a cast cycle, for example, a few dozens of cauldrons, before these plates have been replaced. The two faces of the upper plate A have been used, as indicated by the scratch 24 and 26. Only one side of the lower plate B has been used, the upper face in the example shown, as indicated by the scratched 28 Plate A is discarded and plate B is installed as the top plate. A new plate C is installed as the bottom plate. The situation is as shown in Figure 2c, which is identical to that shown in Figure 2a, with the sole exception that plate B occupies the position that plate A had in Figure 2a, and the plate C the plate that had the plate B. The cycle continues in the same way.

In the example described in relation to figures 1 and 2, a new plate is placed in the lower position. However, it is also possible, according to the invention, to place the new plate in the upper position and then reuse it as the lower plate. The lower plate undergoes more intense erosion because it laminates or flattens the metal. This is the reason why the top plate is less eroded than the bottom plate. Figure 3 shows a top view of a plate according to the present invention, which has an alignment device. This plate has a circular shape 30. The alignment device is composed of a cutting panel 32. The plate is thus asymmetric in relation to one of its axes XX and YY. The profile of the plate in the absence of a cutting panel is determined at 34. 14 and 18 indicate the shape of the upper or lower indentation. As can be seen, this shape follows the periphery of the plate at the level of the cutting panel 32, so that the latter can be installed only in a single position.

Of course, the position of the plate in the upper indentation is different from its position in the lower indentation, so that the supporting face of the plate becomes its working face. However, in the application mode shown in Figure 3 there is nothing to avoid the installation of a plate already used instead of a new plate in the lower indentation. The instrumentation mode of Figures 4 and 5 remedies this disadvantage. Figure 4 shows a cross-sectional view of a preferred way of instrumenting a plate according to the invention. This plate has a means to prevent installation more than once in one of the indentations 14 or 18 of the slide gate. In the example shown, this means consists of a metal part 40 and a spring 42 that are capable of forcing the metal part 40 out of a cavity 44 provided in the thickness of the plate 12 or 16. The metal part 40 maintained by means of a thermofusible substance. During the casting of the steel, under the effect of the heat of the molten metal, plate 12 or 16 is heated and the hot melt element melts, which leaves the metal part free. The metal part 40 then comes into contact with the indentation (indentation 14 in the example shown in Figure 4). When the plate 16 is removed from this indentation, the metal part 40 projects out completely and prevents the placement of the plate 16 in the indentation 14 a second time.

On the other hand, the upper indentation 18 has a groove 46 capable of accepting the metal part 40 (see Figure 5). So, the plate 16 can be installed without difficulty in this indentation after rotating 180 ° in the horizontal plane. Thanks to this device, the operator is systematically forced to install a new plate in the desired indentation, the lower indentation 14 in the example described in figure 4. On the other hand, there is nothing to avoid the simultaneous installation of two new plates, for example, if there was not a used plate. The means for preventing the installation of the plate more than once in the same indentation may be located on the longitudinal axis XX of the plate, as in FIGS. 4 and 5. However, it is preferable that it be located outside this axis. so that the plate is asymmetric in relation to each of its axes XX and YY. In this way, the medium can also perform the function of aligning the device as shown in Figure 3. For example, when the plate is new, it projects outward to penetrate a surface cavity in the lower indentation. After an initial use of the plate, the metal part moves further outwards and can no longer enter the recess of the lower indentation. On the other hand, the recess 46 of the upper indentation is sufficiently deep to receive it. The circulation of the plates is shown in Figure 6. A box 50 contains new plates, which are installed in the lower indentation of the gate 2. The box 52 contains plates that were used only once. These plates are installed in the upper indentation of gate 2. The gate is then ready for a casting cycle. After casting, the gate opens and the plates are removed. The bottom plate once used is recovered in box 54. It is cleaned at 56 and then carried to box 52. The top plate, which was used twice, is discarded in the trash can 58. The plate of the invention can also have more than one hole, for example, it can have two. This offers the advantage of having a new pouring hole when the plate is reused. The surfaces that produce the union with the internal nozzle and with the collector nozzle respectively are also new. The cleaning of the plate is facilitated. The plate can be reused so that its front support face becomes its sliding face or vice versa. But the same face can also be reused as the support face or as the sliding face as long as these are different work zones of the plate.

Figure 7 shows a first variant of instrumentation of a device means that avoids the installation of more than one refractory plate according to the invention more than one in a lower or higher indentation. The plate 14 or 16 having the ring 30 is equipped with a tongue 60 consisting of a metal with a shape memory. It is known that a shape memory metal is able to recover its initial shape when heated to a certain temperature (e.g. 100CC) after it has been deformed. Initially, tab 60 presents an essentially rectilinear shape as indicated by dotted lines. This shape was curved, as indicated by the solid lines, to be able to penetrate the recess 62 of the upper or lower indentation 14 and 16. During casting, the plate is heated to a temperature above 100 ° C, so that the curved tongue 60 returns to its initial shape, as indicated in the dotted lines, as soon as it is extracted from the indentation. Then, it can not be reintroduced a second time in this indentation. Necessarily it would have to be installed in the other indentation which has a recess 64, as shown by the dotted lines and which is capable of accepting the tab 60 in its rectilinear form.

Figure 8 shows a second mode of intrumentation. Two tongues or clamps 66 which are curved at their ends of the tongue 66. A metal part 70 is installed in a seat 74 of the plate 12 or 16 is activated by a spring 72 which tends to force it out of the seat 74. When the The plate is new, the metal part 70 is held by the fastener 68 and can not move outwardly of the seat 74. When the plate is installed in one of the lower or upper indentations, the fastener 68 is ejected so that the metal part 70 abuts against the wall of the indentation 14 or 18. As soon as the plate is removed from this indentation, the metal part 70 projects outwards to take the position indicated by the dot and line lines. Then it is possible that the plate is no longer re-shrunk a second time in the same indentation and has to be installed in another indentation having a seat designed to receive the metal part 70 in its fully extended position. Figures 9 and 10 show a third variant of instrumentation of the medium that prevents the installation of a plate more than once in the same indentation. This means is composed of a tongue 80 fixed on the periphery of the ring 30 of the plate. Initially, the tongue has an essentially rectilinear shape, as indicated by the dot and dash lines in Figure 9. When the new plate is inserted into the indentation, the tongue 80 is rolled, for example, by means of a tool analogous to the key of a can of sardines. Rolling the tongue makes it possible to stick the plate on the indentation. The tongue in this way plays a double role. Avoid the installation of the plate more than once in the indentation and at the same time serves to block the plate. When the plate is removed from the first indentation, the tab 80 that was compressed is easily released, so that it can no longer be reintroduced into the same indentation. The other indentation has a seat 82 that is capable of receiving it. A fourth variant is shown in Figure 11. A key 90 is provided in the plate 12, 16. This key has a recess 92. The key can be moved between a first position (solid lines) and a second position (dot and line lines). stripe) under the effect of an actuator mechanism 91 that is not indicated in detail but that may employ the principles described in the foregoing. In the first position of the key, a metal part 94 installed in the indentation of the new plates enters opposite in the recess 92 when the operator places the plate in its place. The plate can then be installed in this indentation. In the second position of the key 90, a metal part 96 installed in the indentation of the recycled plates falls opposite in the recess 92 when the plate is present.

On the other hand, in the first position of the key, the plate can not be installed in the indentation of the recycled plates, and in the second position of the key, the plate can not be installed in the indentation of the new plates. In this way it is ensured that there is always a set of plates containing a new and a recycled plate.

Claims (19)

1. CLAIMS The process for reusing the plates in a slide gate for a metallurgical vessel, the gate has a higher indentation and a lower indentation to receive a set of two refractory plates, each of these plates resting on an indentation on a face that becomes its supporting face and in cooperation with the other plate by a face that is transformed into its sliding face, the process characterized in that a set of refractories consisting of a new plate combined with a plate that has already been used once used in the sliding gate and in which, when the plates are changed, a new plate is installed in a lower or higher loading indentation, this indentation remains the same in each plate change, the plate used only once is installed in the another indentation, which constitutes an indentation for recycling.
2. The process, according to the previous claim, is characterized in that the plate that is used only once is placed in the recycling indentation so that the face that was its support face during its first use becomes its sliding face.
3. 3. The process, according to any of the above claims, is characterized in that the new plate is used as the bottom plate.
4. 4. The process, according to any of the above claims, is characterized because the new plate is used as the top plate.
5. 5. The refractory plate designed to be installed in an indentation in a slide gate for a metallurgical vessel, such as a cauldron or distributor, the slide gate has an indentation for a top plate and an indentation for a bottom plate, the plate is characterized in that it has an alignment device which allows it to be installed only in a position in the upper indentation and in a single position in the lower indentation, so that the supporting face of the plate is transformed in its face slidable when the plate passes from one position to the other.
6. 6. The refractory plate, according to the previous claim, is characterized in that the alignment device comprises a cutting panel.
7. 7. The plate, according to any of the above claims, is characterized in that it has a means or device that prevents its installation more than once in the indentations of the slide gate without preventing its installation in the other indentation.
8. The plate, according to the previous claim, is characterized because the means that prevents its installation more than once in one of the indentations of the sliding gate without preventing its installation in the other indentation consists of an element capable of being cantilevered under the action of a phenomenon originated by the casting of molten metal, for example, temperature or thermal expansion.
9. The plate, according to claim 8, is characterized in that the means preventing its installation more than once consists of a deformed piece of shape memory material capable of recovering its original shape after being exposed to a certain temperature.
10. The plate, according to the claim 7, is characterized in that the means that prevents its installation more than once in an indentation consists of a mobile element seated in the plate and mechanically locked, this blocking or hooking is eliminated or broken during the introduction of the new plate in the indentation of the new plates, which induces the exit of the mobile element.
11. The plate, according to claim 10, is characterized in that it has a fastener that retains a metal part in a seat and induces it to leave this seat, ejecting the fastener when the plate is put in place for the first time.
12. The plate, according to claim 7 or 8, is characterized in that the means for preventing the installation of the plate more than once in an indentation for new plates consists of a deformation recorded in a portion of the plate when it is inserted into the plate. indentation of the new plates.
13. The plate, according to the claim 12, characterized in that it has a tongue that is rolled after the initial placement of the plate in an indentation of the gate, the second indentation has a seat capable of receiving the tongue after it is wound .
14. The plate, according to any of the above claims, is characterized in that it is ringed.
15. The plate, according to any of the above claims, is characterized in that it has a metallic envelope and because its smaller face is at least equal to 60% of the other face.
16. 16. The plate, according to claim 7, is characterized in that it has a double-position key, the first position of the key prevents the installation of the plate in an indentation of new plates, the "Conduit of the key from the first position to the second is obtained by a remarkably thermal or mechanical effect or by a material with shape memory.
17. 17. The plate, according to any of the previous claims, is characterized in that it has two pouring holes.
18. 18. A sliding gate for a metallurgical vessel having an indentation for an upper plate and an indentation for a lower plate, characterized in that these indentations have a shape so that they can receive an upper plate and a lower plate, equipped with an alignment device except in one position.
19. 19. A slide gate for a metallurgical vessel having an indentation for an upper plate and an indentation for a lower plate, characterized in that only one of these indentations has a means for receiving a reused plate, equipped with the means preventing the installation of this more than once in one of the indentations of the slide gate. .