EP2371471A1 - Internal nozzle for transferring liquid metal contained in a container, system for clamping said nozzle and pouring device - Google Patents

Abstract

The nozzle (12) has a bottom flat contact surface (26) that is enclosed within a perimeter. A metallic bearing surface is recessed with respect to the sliding plane. The side edges define the perimeter and thickness of the plate. The metallic bearing surface is extended from the cladded portion of the side edges beyond the perimeter of the contact surface. The bearing surface is defined by the ledges of separate bearing elements distributed around the perimeter of the plate. An independent claim is included for method for producing inner nozzle.

Description

The present invention relates to the technical field of the continuous casting of liquid metal and more particularly to a device for holding and changing the plate of a metal casting installation.

In a casting plant, the liquid metal is generally contained in a metallurgical vessel, for example a distributor, before being transferred to another container, for example in a casting mold. The metal is transferred from the container to the container by means of a nozzle formed on the bottom of the metallurgical vessel, called the inner nozzle ("inner nozzle" in English), coming into sealing contact with a sliding transfer plate (or casting plate) brought in the extension of the internal nozzle through a holding device and plate change, reported under the metallurgical vessel. This sliding plate makes it possible to transfer the liquid metal, either in the form of a free jet or by guiding the jet when the plate is an external nozzle ("pouring nozzle" or "outer nozzle" in English), comprising a pouring tube.

An example installation is described in the document EP1289696 . In order to ensure a tight contact between the inner nozzle and the sliding plate, the plate holding and changing device comprises on the one hand clamping means intended to press against the internal nozzle, in particular downwards, for the pressing against the frame of the device, and pushing means, intended to press the sliding plate, in particular upwards, so as to press the plate against the inner nozzle, in order to obtain a sealed contact.

As described above, the inner nozzle is a stationary member during casting. Therefore, its life should be substantially that of the metallurgical vessel. The sliding plate, meanwhile, can be replaced during casting thanks to the device for holding and changing the plate

It turns out that the inner nozzle and the plate each comprise, at least in part, a refractory material. A problem lies in the fact that the forces exerted by the clamping or thrusting means tend to exert stress on the refractory material. These stresses can cause the deterioration of the refractory material, in particular cracks.

The invention is intended to provide an internal nozzle whose quality and integrity of the material will be maintained during the life of the nozzle.

For this purpose, the invention particularly relates to an internal nozzle for the transfer of liquid metal contained in a metallurgical vessel, the casting direction defining a vertical direction, the inner nozzle comprising an inner nozzle plate comprising a lower contact surface , extending in a substantially horizontal plane called sliding plane, intended to be in sealing contact with a sliding plate slidably brought facing the inner nozzle by a holding and plate changing device, the internal nozzle further comprising a metal casing and at least one so-called bearing surface intended to be in contact with a frame of the device, extending in a substantially horizontal plane, called the support plane, characterized in that the bearing surface is formed on the metal casing of the nozzle and in that the support plane is set back vertically relative to the sliding plane of the nozzle.

Thus, it is proposed to spare the refractory material of the inner nozzle, providing that the surface of the inner nozzle which rests on the frame is made of metal rather than refractory material. As a result, when a clamping system presses against the inner nozzle to press against the frame, it is a metal surface that is solicited. Consequently, the nozzle is less sensitive to stress, resulting in fewer cracks, less air suction, less risk of metal infiltration, less wear of the nozzle and an improvement in the quality of the metal. sank. Furthermore, the support plane is sufficiently recessed relative to the sliding plane so that the wear of the lower contact surface, made of refractory material, does not interfere with the setting of the internal nozzle in the frame .

Preferably, the envelope is metallic but all the other materials making it possible to fulfill the same function could be envisaged. Preferably, the metal casing is thick and has walls having a thickness greater than 6 mm. This facilitates the flowability of the envelope, for example cast iron, during manufacture. Thus, relatively complex envelope shapes can be obtained while keeping acceptable manufacturing costs.

Note that the bearing surface presented above, made of metal, has a sufficient area for the inner nozzle can bear on the frame. In particular, the bearing surface is distinguished from a simple peripheral wall of a traditional metal shell, whose thickness rarely exceeds 2 or 3 mm (millimeters). Such a dimension is not sufficient to serve as a support surface.

In the present application, the term "clamping system"("clampingsystem") means a clamping system of the inner nozzle, for exerting pressure on the inner nozzle to immobilize it with respect to the frame on which is mounted the clamping system. Generally, the force exerted by the clamping system on the inner nozzle is a force directed in particular downwards, applied to an upper surface of the inner nozzle. The vertical direction is further defined as the direction of flow of the liquid metal at the outlet of the metallurgical vessel, the longitudinal direction as the direction of plate change of the device, and the transverse direction as the direction perpendicular to the other two directions vertical and longitudinally, so that the longitudinal, transverse and vertical directions define an orthogonal reference. In addition, it will be noted that the forward direction is defined with reference to the direction of plate change in the plate changing device, the plate being moved from the rear to the front to take the following successive positions: waiting position (when another plate is already in the pouring position), casting position (when a pouring orifice formed on the plate extends the pouring channel of the internal nozzle), position shutter (when a sealing surface formed on the plate closes the pouring channel) and ejection position (when the sliding face of the plate is disengaged from the pouring channel). It will also be noted that the inner nozzle and / or the sliding plate are generally each composed of a metal casing surrounding a refractory element, and that the sliding plate may optionally be an external nozzle, comprising a pouring tube made of refractory element.

The inner nozzle may further include one or more of the following features, taken alone or in combination.

The bearing surface projects from a peripheral surface of the inner nozzle plate. "Peripheral surface" means the surface extending from the periphery of the lower contact surface of the plate, preferably in a substantially vertical direction.

The bearing surface has a length and a width, each having a dimension greater than 5 mm, preferably equal to or greater than 10 mm. Thus, the surface has an area large enough for the nozzle to bear on the frame.

The nozzle comprises at least two separate bearing surfaces. "Separate surfaces" means separate, non-contiguous surfaces. They may for example be separated from each other by an empty space or by a rib.

The nozzle comprises three distinct bearing surfaces, and only three. These bearing surfaces make it possible to provide satisfactory support at three distinct points while optimizing the space available around the nozzle and in the device for holding and changing the plate, this space being more free than when the nozzle has four or more bearing surfaces.

The nozzle comprises a vertical central longitudinal plane and the three bearing surfaces are arranged in a Y on the periphery of the metal casing, the base of the Y being disposed in said longitudinal plane and the two branches of the Y being disposed on both sides. other of this plan. Preferably, the two branches of Y are symmetrical with respect to the central plane. This Y-shaped arrangement of the bearing surfaces makes it possible to ensure, in a particularly satisfactory manner, the clamping of the nozzle while limiting the bulk of the clamping system and by implementing a particularly simple clamping method. Note that the plane corresponds to a central vertical longitudinal plane, that is to say that it extends in the longitudinal and vertical directions of the nozzle and that it passes through the center of the nozzle, this center can be defined by the center of the casting orifice of the inner nozzle. Note that for a symmetrical inner nozzle, in which the casting orifice is disposed at the center of the contact or sliding surface, the center of the inner nozzle corresponds to the center of the casting orifice of the inner nozzle. Furthermore, for an asymmetrical nozzle, for example having a generally rectangular shape and in which the casting channel is not disposed in the center of the contact surface, the center of the inner nozzle corresponds to the center of the contact surface of the nozzle, for example the center of the rectangle circumscribed to the contact surface of the nozzle.

The metal shell has four contiguous edges, namely two longitudinal edges and two transverse edges, the longitudinal direction being defined by the direction of plate change in the device, the bearing surface or surfaces being provided only on the transverse edges of the envelope. The bearing surfaces thus positioned in the transverse direction make it possible to reference the inner nozzle with respect to the holding and plate changing device along the transverse direction, which is particularly interesting. Indeed, the internal nozzle undergoes a number of tensions in the longitudinal direction during the plate changes, so that the clamoring forces distributed in the transverse direction, which allow to press the nozzle against the frame, can wedge the internal nozzle in the longitudinal direction, and thus to immobilize it in the longitudinal direction despite the movements due to plate changes. Preferably, there are no bearing surfaces in the longitudinal direction of the nozzle. Thus, it is proposed to exert the clamping force and the support against the frame along the transverse edges of the inner nozzle, so that the sealing is improved at the transverse edges of the internal nozzle contact plane. sliding plate, while preferably maintaining a thrust force on the longitudinal edges of this contact plane. Thus, thanks to the clamping means and the thrust means thus arranged, it is possible to exert a force imposing the contact on substantially the entire circumference of the internal nozzle / sliding plate contact plane, hence a better sealing, therefore a longer duration of parts life and better quality of cast metal. In particular, the inventors have found that it is more advantageous to exert forces in this way than when the thrust force and the clamping force are applied opposite each other, as is practiced in the state of the art, because the strong pressure on the longitudinal edges of the inner nozzle and the sliding plate can generate a spacing of the respective transverse edges.

The nozzle comprises at least one wedging flange of the inner nozzle against a frame provided on the holding device and the plate changing device, the calibration flange comprising

the support surface,

a so-called clamming surface on which a clamping system is intended to apply a clamping force, arranged opposite the bearing surface, this clamping surface being formed on the metal casing of the nozzle.

The chock flange is made entirely of metal. In other words, the metal rim is solid, that is to say that there is only metal between the bearing surface and the clamming surface, so that only metal is put under stress during clamping, which spares the refractory material of the internal nozzle. Alternatively, the metal surfaces of the flange may be separated by a non-metallic material such as refractory.

The wedging flange of the nozzle is sandwiched between the frame and the clamping system.

The bearing surfaces or the clamping surfaces are flat. Alternatively, the surfaces may have different shapes, for example, inclined, curved or grooved. The bearing surfaces or the clamping surfaces extend in a substantially horizontal plane. Of preferably, the bearing surfaces or clamage are in a substantially horizontal plane. It is important that the surfaces can fulfill their roles as support surfaces or as clamping surfaces. Similarly, an element such as fiber, a seal or a compressible element could be associated (added, glued or juxtaposed) to the support or clamming surface. The advantages of the present invention are retained.

The invention also relates to a metal casing for an inner nozzle as described above, and a method of assembling a metal casing and a refractory element to manufacture such an inner nozzle.

The invention furthermore relates to a set of an internal nozzle and a device for holding and changing a sliding plate for the transfer of liquid metal contained in a metallurgical vessel, the internal nozzle comprising a metal casing, the device comprising

a frame in contact with at least one surface of the nozzle called a bearing surface, and

a clamping system disposed opposite the frame, arranged to press on a surface of the internal nozzle called the clamping surface,

characterized in that the bearing surface of the inner nozzle is provided on the metal casing.

As previously described, it is expected that the surface of the inner nozzle which rests on the frame is made of metal rather than refractory material. Also, when the clamping system presses against the inner nozzle to press against the frame, it is a metal surface that is solicited, hence the advantages described above.

Preferably, the inner nozzle comprises an inner nozzle plate carrying a lower contact surface, extending in a substantially horizontal plane called sliding plane, the lower contact surface being intended to be in sealing contact with a sliding plate brought by sliding opposite the internal nozzle by the device for holding and changing the plate, the bearing surface of the inner nozzle extending in a substantially horizontal plane, called the support plane, together in which the support plane is set back vertically with respect to the sliding plane.

• la figure 1 est une vue en perspective d'une busette interne selon un mode de réalisation ;
• la figure 2 est une vue en perspective de dessus de la busette de la figure 1 lorsqu'elle est retournée dans la direction verticale ;
• la figure 2a est une vue agrandie du rebord de calage ;
• la figure 3 est une vue en perspective avec arrachement suivant deux demi-plans axiaux de la busette de la figure 1 et d'un dispositif de maintien et de changement de plaque ;
• la figure 4 est une vue en coupe suivant les deux demi-plans axiaux de la figure 3 ; et
• les figures 5 et 5a sont des vues schématiques de dessus de la busette de la figure 1.

The invention will be better understood on reading the description which follows, given solely by way of non-limiting example of the scope of the invention and with reference to the drawings, in which:

• the figure 1 is a perspective view of an internal nozzle according to one embodiment;
• the figure 2 is a perspective view from above of the nozzle of the figure 1 when returned in the vertical direction;
• the figure 2a is an enlarged view of the cushioning flange;
• the figure 3 is a perspective view with tearing along two axial half-planes of the nozzle of the figure 1 and a device for holding and changing the plate;
• the figure 4 is a sectional view along the two axial half-planes of the figure 3 ; and
• the Figures 5 and 5a are schematic views from above of the nozzle of the figure 1 .

In the following, the vertical direction corresponding to the direction of casting is indicated as the direction Z, the longitudinal direction corresponding to the direction of change of the plate is indicated as the direction X, and the transverse direction is indicated as the direction Y. The X, Y, Z directions are orthogonal to each other.

In a continuous casting installation of liquid metal, for example liquid steel, a device 10 for holding and changing a sliding plate makes it possible to transfer the metal contained in a metallurgical vessel, for example a distributor, to a container, such as one or more casting molds. The device 10, represented in particular on the figure 3 , is attached under the metallurgical vessel, in the vicinity of an inner nozzle 12, fixed in the bottom of the metallurgical vessel, for example by cement. The internal nozzle 12 delimits a casting channel 14 of axis A and the device 10 is arranged so that it can guide a sliding plate to a casting position in which the sliding plate extends the casting channel 14 of the nozzle 12. For this purpose, the device 10 comprises on the one hand guiding means 16 of the sliding plate from a waiting position to a casting position, for example guide rails 16. The rails 16 are arranged on the along the longitudinal edges of the device 10. The device 10 further comprises thrust means (not shown) of the plate in the casting position against the inner nozzle 12, for example compression springs, these means being arranged to exert a force on a lower surface of each of the two longitudinal edges of the sliding plate, so as to push the plate in sealing contact against the inner nozzle 12. The springs are distributed over the Longitudinal edges of the device 10. The device 10 further comprises means 20 for clamping the internal nozzle, forming a clamping system, arranged to exert a force on an upper surface of two opposite transverse edges of the inner nozzle 12, in order to keep the inner nozzle bearing against the device 10.

The inner nozzle 12 comprises a metal casing 22, surrounding a refractory element 24 defining the pouring channel, as shown in FIG. figure 1 . The metal casing 22 reinforces the refractory element 24, it is relatively thick, its walls having a thickness greater than 6 mm (millimeters). The metal casing delimits an inner nozzle plate, carrying a lower contact surface 26, shown in FIG. figure 2 , extending along a substantially horizontal sliding plane P _g , parallel to the (X, Y) plane. The lower contact surface 26 is intended to be in sealing contact with the sliding plate when the sliding plate is slidably brought into the casting position, that is to say facing the inner nozzle 12, by the device 10. The lower contact surface 26 is traversed by a pouring orifice 28, on which the pouring channel 14 opens. The envelope 22, therefore the internal nozzle 12, comprises three flanges 30a, 30b, 30c for wedging the internal nozzle 12 against a frame 31 of the device 10, namely a first 30a, a second 30b and a third flange 30c. Each flange 30a, 30b, 30c has an upper surface 32a, 32b, 32c called said clamping surface, on which the clamping means 20 are intended to apply a clamping force, and a lower surface 34a, 34b, 34c said surface of support, intended to be in contact with the frame 31, extending each in a horizontal plane parallel to the plane (X, Y), called support plane P _a . In this example, the surfaces 34a, 34b, 34c are coplanar, so there is only one support plane. Alternatively, the bearing surfaces may be located at different heights, so there are in this case several support planes. As can be seen in particular on the figure 4 the support plane P _a is set back vertically with respect to the lower contact surface 26. Furthermore, the bearing surfaces 34a, 34b, 34c are substantially rectangular, and have a length L and a width I each having a dimension greater than 5 mm, preferably greater than or equal to 10 mm ( figure 2a ). The clamping surfaces 32a, 32b, 32c are each arranged facing the bearing surfaces 34a, 34b, 34c, so that the clamping means 20 and the frame 31 sandwich the wedging edges 30a, 30b, 30c under the action of the clamping means 20.

The wedging flanges 30a, 30b, 30c are distinct, i.e. they are separate, non-contiguous. More precisely in this example, the wedging flanges 30a, 30b, 30c protrude in substantially parallelepipedal shape from a peripheral surface 36 of the plate of the inner nozzle 12, this surface 36 extending from the lower contact surface 26 of the plate, preferably in a substantially vertical direction Z. Still in this example, the three wedging flanges 30a, 30b, 30c are made entirely of metal, that is to say that there is only metal between the bearing surfaces 34a, 34b, 34c and the clamping surfaces 32a, 32b, 32c.

As can be seen on the Figures 5 and 5a , the inner nozzle 12 has two substantially longitudinal edges 40a, 40b and two substantially transverse edges 42a, 42b, namely a front transverse edge 42b and a rear transverse edge 42a. It further comprises a vertical central vertical plane P and the three wedging flanges 30a, 30b, 30c are arranged in Y on the periphery 36 of the nozzle 12, the base 44a of the Y being disposed in the central longitudinal plane P and the two branches 44b, 44c of Y being disposed on either side of this plane P. More specifically, the second 30b and third 30c wedging flanges have a second 32b and a third 32c clamming surfaces, each of these second 32b and third 32c surfaces being disposed on either side of the longitudinal plane P and preferably symmetrically. In addition, the surfaces 32b, 32c each have a center 32'b, 32'c positioned at an angle α (alpha) between 30 and 45 ° relative to the longitudinal plane P, with reference to the center 46 of the inner nozzle 12 , corresponding to the center of the casting orifice 28. In addition, each of the second 32b and third 32c clamming surfaces is included in an angular sector β (beta) between 10 and 20 ° with reference to the center 46 of the inner nozzle 12. Furthermore, the first wedging flange 30a has a first clamping surface 32a passing through the longitudinal plane P of the nozzle 12. More specifically, the surface 32a extends substantially symmetrically relative to the plane P, the center 32'a of this surface being positioned in the plane P. The surface 32a extends in a surface included in an angular sector γ (gamma) between 14 and 52 ° with reference to the center 46 of the inner nozzle. As can be seen, the flanges 30a, 30b, 30c, so the bearing surfaces 34a, 34b, 34c are formed only on the transverse edges 42a, 42b of the casing. Note that in the case of an internal nozzle having a generally rectangular shape as illustrated in FIGS. Figures 5 and 5a , the central longitudinal plane is the plane perpendicular to the lower contact surface 26 comprising the median of the two sides of greater length of the circumscribed rectangle.

The clamping means 20 comprise three clamping elements 50a, 50b, 50c, visible on the figure 3 , arranged at Y at the periphery of the inner nozzle 12, namely a first clamping element 50a at the base of the Y, disposed on the rear part of the central longitudinal plane P and a second 50b and a third 50c clamping elements, ends of the two branches of the Y, disposed on either side of the front portion of this plane P. As can be seen, the clamping means are arranged to exert their force on the transverse edges 42a, 42b of the inner nozzle . The clamping elements 50a, 50b, 50c have a configuration complementary to the configuration of the wedging flanges 30a, 30b, 30c. Thus, the first 50a, the second 50b and the third 50c clamping members respectively exert a clamping force on the first 32a, second 32b and third 32c clamping surfaces described above. The clamping elements 50a, 50b, 50c are movably mounted between a rest position and a clamping position. In the clamming position, the elements 50a, 50b, 50c come into contact with the clamping surfaces 32a, 32b, 32c, so as to exert a clamping force by pressing on these surfaces. For this purpose, the clamping elements 50a, 50b, 50c can be actuated by a rotating cam member in contact with the elements 50a, 50b, 50c. Optionally, one or more of the elements 50a, 50b, 50c is actuated by means connecting rod-crank.

As can be seen from the Figures 3 and 4 when the internal nozzle 12 is coupled with the device 10, the bearing surfaces 34a, 34b, 34c rest on bearing surfaces 80a, 80b, 80c formed on the frame 31. Thus, the flanges 30a, 30b , 30c are sandwiched between the clamping elements 50a, 50b, 50c and the bearing surfaces 80a, 80b, 80c of the frame. The bearing plane P _formed by the surfaces 34a, 34b, 34c is retracted vertically relative to the sliding plane P _g. In the example, the bearing surface or surfaces are the lower surfaces of the wedging flange and the clamping system exerts a force, particularly downward, on the upper surface of the flange. However, the support and clamming surfaces could be reversed with a clamoring system exerting a force including upward. The inner nozzle would be clamored upwardly abutting against a reference surface of the frame. Also in this embodiment, the wedging flange (s) may be sandwiched between a clamper and a bearing surface.

Among the advantages of the nozzle 12 and the device 10 described above, it will be noted that the bearing surfaces 34a, 34b, 34c made in the metal casing are worn less rapidly than if they were made in the refractory element. 24. The stresses are concentrated in the metal edges.

Furthermore, the clamping means exert their force on the transverse edges 42a, 42b of the inner nozzle, while the thrust means 18 exert their force on the longitudinal edges of the sliding plate, at the longitudinal edges of the device 10. It follows that pressure is exerted on substantially the entire circumference of the contact surface between the inner nozzle 12 and the sliding plate, hence a better contact between nozzle internal and sliding plate, resulting in a better seal.

Note that the invention is not limited to the previously described embodiments.

In particular, the invention relates to an internal nozzle of a holding and plate changing device, for example a tube changing device or calibrated plate change. The nozzle according to the invention can also be used in a holding and plate changing device in which, for example, a casette comprising two or more plates is brought by sliding opposite a pouring orifice of a metallurgical vessel. .

10

Dispositif de maintien et de changement de plaques

12

Busette interne

16

Moyens de guidage

20

Système de clamage

22

Enveloppe métallique

26

Surface inférieure de contact

30a, 30b, 30c

Rebord de calage

31

Bâti

32a, 32b, 32c

Surface de clamage

34a, 34b, 34c

Surface d'appui

36

Surface périphérique

40a, 40b

Bords longitudinaux

42a, 42b

Bords transversaux

Pa

Plan d'appui

Pg

Plan de glissement

X

Direction de changement de plaque

Y

Direction transversale

Z

Direction de coulée

In addition, during the process of assembling the casing 22 and the refractory element 24 to manufacture the inner nozzle 12, it is possible to use a metal casing 22 already used and to associate a new refractory element 24 or a refractory element recycled. The inner nozzle could also be made of several refractory elements assembled together before use. In particular, the plate of the nozzle and its tubular part can be two distinct elements

10

Device for holding and changing plates

12

Internal nozzle

16

Means of guidance

20

Clamming system

22

Metal envelope

26

Lower contact surface

30a, 30b, 30c

Calibration edge

31

built

32a, 32b, 32c

Clamming surface

34a, 34b, 34c

Bearing surface

36

Peripheral surface

40a, 40b

Longitudinal edges

42a, 42b

Transversal edges

Pa

Support plan

Pg

Slip plane

X

Plate change direction

Y

Cross direction

Z

Casting direction

Claims (14)

Internal nozzle (12) for the transfer of liquid metal stored in a metallurgical vessel, the casting direction defining a vertical direction (Z), the inner nozzle comprising an inner nozzle plate having a lower contact surface (26), extending in a substantially horizontal plane called slip plane (P _g ), intended to be in sealing contact with a sliding plate slidably brought opposite the inner nozzle by a device (10) for holding and changing the plate, the nozzle internal device further comprising a metal casing (22) and at least one so-called bearing surface (34a, 34b, 34c) intended to be in contact with a frame (31) of the device (10), extending in a plane substantially horizontal, called support plane (P _a ), characterized in that the bearing surface (34a, 34b, 34c) is formed on the metal casing (22) of the nozzle and in that the support plane (P _a ) is indented green icalement with respect to the sliding plane (P _g ) of the nozzle. Nozzle according to the preceding claim, wherein the bearing surface (34a, 34b, 34c) projects from a peripheral surface (36) of the plate of the inner nozzle. Nozzle according to any one of the preceding claims, wherein the bearing surface (34a, 34b, 34c) has a length (L) and a width (I), each having a dimension greater than 5 mm, of equal or equal greater than 10 mm. Nozzle according to any one of the preceding claims, comprising at least two separate bearing surfaces (34a, 34b, 34c). Nozzle according to the preceding claim, comprising three separate bearing surfaces (34a, 34b, 34c), and only three. Nozzle according to the preceding claim, comprising a vertical central longitudinal plane (P) and in which the three bearing surfaces (34a, 34b, 34c) are arranged in Y on the periphery of the metal casing (22), the base of the Y being disposed in said longitudinal plane (P) and the two branches of Y being disposed on either side of this plane (P). Nozzle according to any one of the preceding claims, wherein the metal shell (22) comprises four contiguous edges (40a, 42a, 40b, 42b), namely two longitudinal edges (40a, 40b) and two transverse edges (42a, 42b), the longitudinal direction being defined by the direction of plate change in the device, the bearing surface or surfaces (34a, 34b, 34c) being formed only on the transverse edges of the envelope. Nozzle according to any one of the preceding claims, comprising at least one flange (30a, 30b, 30c) for wedging the inner nozzle against the frame (31) provided on the holding and plate changing device, the wedging flange (30a, 30b, 30c) comprising the bearing surface (34a, 34b, 34c), - A so-called clamming surface (32a, 32b, 32c) on which a clamping system (20) is intended to apply a clamping force, disposed opposite the bearing surface, this clamping surface being formed on the metal shell (22) of the nozzle (12). Nozzle according to the preceding claim, wherein the wedging flange (30a, 30b, 30c) is made entirely of metal. Metal shell for an inner nozzle according to any one of claims 1 to 9. A set of an inner nozzle (12) and a sliding plate holding and changing device (10) for transferring liquid metal contained in a metallurgical vessel, the inner nozzle comprising a metal shell (22), the device comprising a frame (31) in contact with at least one surface of the nozzle called a bearing surface (34a, 34b, 34c), and - A clamping system (20) disposed opposite the frame, arranged to press on a surface (32a, 32b, 32c) of the inner nozzle called clamping surface, characterized in that the bearing surface (34a, 34b, 34c) of the inner nozzle is provided on the metal casing (22). Assembly according to the preceding claim, wherein the inner nozzle comprises an inner nozzle plate comprising a lower contact surface (26), extending in a substantially horizontal plane called sliding plane (P _g ), the lower contact surface being intended to be in leaktight contact with a sliding plate slidably brought opposite the internal nozzle by the holding and plate changing device, the bearing surface (34a, 34b, 34c) of the internal nozzle extending according to a substantially horizontal plane, called support plane (P _a ), together in which the bearing plane is set back vertically relative to the sliding plane. An assembly according to claim 11 or 12, wherein the inner nozzle is a nozzle according to any one of claims 1 to 9. A method of manufacturing an inner nozzle according to any one of claims 1 to 9 comprising a step of assembling a metal shell (22) and a refractory element (24).

Images