Robotic ladle turret system

Abstract

The present invention relates to a metal casting facility comprising (a) a loading platform (20), (b) a tundish (1), and (c) a first ladle (11) and a second ladle (12), wherein each of the first and second ladles comprises: a bottom having an opening (11o, 12o), a collector nozzle (14) and a ladle cover (13a-13c), a ladle sliding gate (15) configured to move the collector nozzle and the ladle cover between a sealed position where the opening is sealed, a casting position where the opening faces the ladle cover (13a-13c), and a clog-free position where the opening faces the collector nozzle (14); and (d) a turret (30) for holding the first and second ladles (11, 12) configured to move and hold the first and second ladles in place over the tundish (1) between a loading station and a casting station. The metal casting facility The robot (21) is configured to perform the following operations with respect to a first or second ladle held at a loading station: · loading a new ladle cover (13b) into a ladle sliding gate (15) and · attaching a drive device (17) to a ladle sliding gate (15).

Description

Technology Field

[0001] The present invention relates to a robotic loading station for preparing a new ladle loaded on a rotary turret before being transported to a casting station on a tundish. In particular, the present invention relates to a robotic facility for loading a ladle shroud onto a ladle sliding gate coupled to the ladle outlet and for coupling a drive device to both the ladle and the ladle sliding gate to operate the ladle sliding gate. The robotic loading station is also configured to uncouple the drive device and unload the used ladle shroud from an empty ladle recently removed from a casting station on a tundish. Robotization of these operations saves the operator from strenuous work and improves the reproducibility of the operation. A specific ladle sliding gate including a collector nozzle located next to the ladle shroud enables rapid unclogging of the outlet in the event of a blockage. Background Technology

[0002] In a continuous metal forming process, the metal melt (2) is transferred from one metallurgical vessel to another vessel, mold, or tool. For example, as shown in FIG. 1, a ladle (11, 12) is filled with the metal melt from a furnace (not shown) and transferred over a tundish (1) to discharge the molten metal from the ladle into the tundish through the ladle shroud (13a-13c). The metal melt can then be cast from the tundish through an injection nozzle (3) into a mold or tool for continuously forming a slab, billet, beam, thin slab, etc. The flow of the metal melt from the ladle to the tundish, and from the tundish to the mold or tool, is driven by gravity. The flow rate can be controlled by a sliding gate that is in fluid communication with the outlets of the ladle and the tundish. A ladle sliding gate (15) can be used to control the flow from the ladle and even block the flow at the sealed position. Similarly, a tundish sliding gate (5) can be used to control the flow from the tundish and block the flow at the sealed position.

[0003] Since casting metal into a mold or tool must be performed continuously, the tundish acts as a buffer, and the level of molten metal within the tundish must be maintained substantially constant throughout the entire casting operation. To maintain a substantially constant level of molten metal in the tundish, it is necessary to ensure a semi-continuous supply of molten metal to the tundish by rapidly replacing the old ladle with a new ladle filled with molten metal after the old ladle is emptied, so that the metal is injected into the tundish at substantially the same rate as it flows into the mold or tool. This operation tends to be more complex due to the following constraints.

[0004] First, for safety reasons and to avoid any collision, the ladle (11, 12) cannot be transported from the furnace to the corresponding tundish over the workshop, and the ladle cover (13a-13c) is attached to the bottom of the ladle and extends more than 1 m below the bottom of the ladle, and the ladle has a sealed position where the opening is sealed, a cast position where the opening is fluidly in communication with the ladle cover, and a clearing position where the opening is fluidly in communication with the collector nozzle.

[0005] Second, to prevent the metal contained in the second ladle (12) from freezing upon contact with the 'cold' moving part of the ladle sliding gate (15) which is maintained in a sealed position, and thus to avoid it sticking to the mechanism and obstructing the opening of the ladle sliding gate, the inner bore of the inner nozzle is generally filled with a plugging material (19), which is typically sand or other fine particulate material, thereby preventing any molten metal from reaching the gate mechanism and thus preventing metal freezing and clogging of the nozzle and gate system. When the ladle sliding gate is opened to the casting position where the ladle is located at the casting station, the sand is discharged, and subsequently, the molten metal can flow through the ladle cover into the tundish. However, sometimes the plugging material locally combines with the frozen metal to form a solid plug, which obstructs the discharge of the plugging material. Consequently, the inner nozzle becomes clogged, and no metal can be discharged from the ladle into the tundish even though the ladle sliding gate is in the casting position. This problem can be easily solved with a clearing tool (19r) inserted into or near the bore of the inner nozzle. The clearing tool (19r) may be a pressurized gas lance or a long rod, as illustrated in FIGS. 2c and FIGS. 3c. Now, this seemingly simple operation is actually very complicated due to the long ladle cover (13a-13c) that is coupled to the ladle sliding gate.

[0006] For this reason, in most facilities, the ladle cover is not autonomously coupled to the sliding gate at the loading station, but instead is inserted over the collector nozzle and held in place by a robot at the casting station. This allows the ladle cover to be removed from the collector nozzle by the robot in the event that the ladle outlet is blocked, for easier access to it from the bottom using a clearing tool (19r). Once the blocked passage is cleared, the ladle sliding gate can move to a sealed position, and the robot reintroduces the ladle cover over the collector nozzle. At this point, the ladle sliding gate moves back to the casting position and begins casting molten metal into the tundish.

[0007] A newly filled ladle is transported from the furnace to the casting facility with the ladle sliding gate fixed to the bottom of the ladle but without a driving force to induce relative movement of the plate forming the ladle sliding gate. For this reason, many metallurgical facilities use a turret (30) comprising a first holding device for holding a first ladle (11) at a casting station on a tundish (1) and a second holding device for holding a second ladle (12) filled with molten metal at a loading station. While the first ladle discharges the molten metal contained therein into the tundish, the second ladle can be prepared to perform the same operation after the first ladle is emptied. In particular, a driving device such as a hydraulic piston may be coupled to the bottom of the ladle and to the ladle sliding gate to enable the operation.

[0008] US2006 / 0118268 describes a ladle sliding gate configured to autonomously hold a ladle cover and a collector nozzle installed side by side. One or more driving devices, such as hydraulic pistons, may be used to operate the ladle sliding gate by moving the plate between a sealing position where the opening is sealed, a casting position where the opening is fluidly in communication with the ladle cover, and a clearing position where the opening is fluidly in communication with the collector nozzle. In this way, if the internal bore becomes clogged, the ladle sliding gate moves to the clearing position so that a clearing tool (19r) can be easily introduced through the short collector nozzle bore to break up the solidified metal-bonded plugging material. Once the plugging material can flow again, the ladle sliding gate moves the collector nozzle out of the mating state from the ladle outlet and moves the ladle cover to the casting position so that the molten metal can flow through the ladle cover into the tundish. The operation of the unclogging tool (19r) can advantageously be performed by a robot located adjacent to the casting station. A clear advantage over the robot described earlier holding the ladle cover is that using this ladle sliding gate eliminates the need for a robot to hold the ladle cover, and instead allows it to be used for the unclogging tool (19r). Otherwise, this operation would have to be performed manually by a human operator or a second robot installed adjacent to the casting station to unclog the internal bore. Manual operation is generally more strenuous and takes longer than when the robot performs this operation. This is disadvantageous because new molten metal cannot be supplied to the tundish by the ladle for a longer period, the level of molten metal in the tundish is lower, and / or the casting operation must be performed at a lower flow rate for a longer period, which impairs the quality of the beam thus produced.Examples of this type of ladle sliding gate having a collector nozzle and a ladle cover side by side are illustrated in FIGS. 2 and 3 and will be described in more detail further.

[0009] US8215375 describes a continuous casting plant having at least one multifunction robot for implementing a plurality of different process controls or automated interventions in the continuous casting plant. The multifunction robot is arranged on a pivotable arm on a rotating column attached to the pouring platform of the continuous casting plant, and the robot can pivot on the pivot arm between a retracted position and an operating position. The robot is also movable on the arm.

[0010] The operation of rapidly replacing an empty first ladle with a filled second ladle at a casting station remains a tricky operation. This operation tends to be even more critical when the internal bore becomes clogged, which can increase the time the tundish is not replenished with new molten metal. The metal casting industry requires a reproducible and shorter ladle replacement operation. The present invention proposes a metal casting facility having a fully automated ladle change operation, including the case where the ladle outlet is clogged by frozen plugging material (19), which allows for a reproducible and shorter replacement operation in all cases. These and other advantages of the present invention are described in more detail in the following section. means of solving the problem

[0011] The objective of the present invention is achieved by a metal casting facility, which is

[0012] (a) Loading platform,

[0013] (b) tundish,

[0014] (c) As a first ladle and a second ladle, each of the first and second ladles is,

[0015] · Floor with an opening,

[0016] · Collector nozzle and ladle cover,

[0017] · A first ladle and a second ladle comprising a ladle sliding gate configured to reversibly receive and support a collector nozzle and a ladle cover, and also configured to be coupled to a driving device to operate the ladle sliding gate between a sealing position where the opening is sealed, a casting position where the opening is fluidly in communication with the ladle cover, and a clearing position where the opening is fluidly in communication with the collector nozzle,

[0018] (d) A turret comprising at least a first holding device and a second holding device for holding a first ladle and a second ladle, respectively, wherein the ladle turret is configured to move and hold the first and second ladles in place between a loading station adjacent to a loading platform and a casting station on a tundish, and the turret comprises

[0019] The metal casting facility includes a robot, and the robot is configured to perform the following actions on a first or second ladle held at a loading station:

[0020] · The action of loading a new ladle cover onto the ladle sliding gate, and

[0021] · Operation of connecting a driving device to a ladle sliding gate.

[0022] The robot is preferably also configured to remove the following from an empty first or second ladle held at a loading station after being moved from a casting station:

[0023] · Ladle cover and

[0024] · Driving device.

[0025] The loading platform preferably includes a tool storage rack containing one or more spare ladle covers within the reach of the robot. The spare ladle covers may be preheated in the storage rack or in a separate oven. The storage rack preferably includes one or more drive devices and / or additional spare collector nozzles, and / or tools.

[0026] In a preferred embodiment, the robot is movably mounted on a loading platform so that the robot can translate parallel to a first axis (X) and / or a second axis (Y) perpendicular to the first axis (X) or a combination thereof, and / or rotate about a vertical axis (Z) perpendicular to the first and second axes (X, Y), to reach and retrieve any tool or component from a storage rack, and to reach a ladle sliding gate of a first or second ladle held at a loading station to perform the operations of loading / unloading a ladle cover and combining / removing a drive device.

[0027] The ladle sliding gate is important in the present invention. In the first embodiment, the ladle sliding gate is,

[0028] (a) As an upper plate,

[0029] · Fixed surface and bottom sliding surface separated from each other by the thickness of the upper plate,

[0030] · Includes an upper bore extending from a fixed surface to a lower sliding surface, and

[0031] · The fixed surface of the upper plate is rigidly fixed to the lower part of the first or second ladle corresponding to the state in which the upper bore is in fluid communication with the opening, the upper plate

[0032] (b) As a lower plate,

[0033] · Nozzle sliding surface and upper sliding surface separated from each other by the thickness of the lower plate,

[0034] · Includes a lower bore extending from the upper sliding surface to the nozzle sliding surface, and

[0035] · A lower plate is slidably mounted so that the upper sliding surface can slide translationally along the lower sliding surface to allow the lower bore to enter and exit a fluid communication state with the upper bore,

[0036] (c) A drawer configured to rigidly hold a ladle cover having a cover bore opening on an upper cover surface and a collector nozzle having a collector bore opening on an upper collector surface, wherein the drawer is movably mounted to translate the upper cover surface and the collector surface along the nozzle sliding surface of a lower plate between, for example, a cover position where the cover bore is in fluid communication with the lower bore and a collector position where the collector bore is in fluid communication with the lower bore.

[0037] (d) a driving device coupled to the lower plate to drive the translation of the lower plate, and

[0038] (e) Includes a drawer driving device coupled to the drawer to drive the translation of the drawer, and

[0039] The driving device comprises a cylinder coupled to the lower plate and rigidly and reversibly coupled to the bottom portion of a corresponding first or second ladle, and a piston rigidly and reversibly fixed to the lower plate, and the driving device is configured to move the lower plate to cause the lower bore to enter and exit a mating state with the upper bore, and

[0040] The drawer driving device is coupled to the drawer and includes a cylinder that is rigidly and reversibly coupled to the bottom portion of a corresponding first or second ladle, and a piston that is rigidly and reversibly fixed to the drawer, and the drawer driving device is configured to move the drawer so as to cause the cover bore and the collector bore to enter and exit a mating state with the lower bore.

[0041] In an alternative embodiment, the ladle slide gate is,

[0042] (a) As an upper plate,

[0043] · Fixed surface and bottom sliding surface separated from each other by the thickness of the upper plate,

[0044] · Includes an upper bore extending from a fixed surface to a lower sliding surface, and

[0045] · The fixed surface of the upper plate is rigidly fixed to the lower part of the first or second ladle corresponding to the state in which the upper bore is in fluid communication with the opening, the upper plate

[0046] (b) As a lower plate,

[0047] · Nozzle surface and upper sliding surface separated from each other by the thickness of the lower plate,

[0048] · Each includes a first bore and a second bore extending from the upper sliding surface to the nozzle surface, and

[0049] · The lower plate is slidably mounted so that the upper sliding surface can slide along the lower sliding surface to allow each of the first and second bores to enter and exit a fluid communication state with the upper bore, and

[0050] The nozzle surface comprises the lower plate configured to be rigidly and reversibly coupled to a ladle cover having a ladle bore in fluid communication with a first bore and a collector nozzle having a collector bore in fluid communication with a second bore, and the driving device comprises a cylinder coupled to the lower plate and rigidly and reversibly coupled to the bottom portion of the corresponding first or second ladle, and a piston rigidly and reversibly fixed to the lower plate, and the driving device is configured to move the lower plate to cause the first and second bores to enter and exit a mating state with the upper bore.

[0051] The driving device may be hydraulically, pneumatically, or electrically operated. At least one first holding device and a second holding device of the ladle turret each have

[0052] · A source of pressurized fluid or a source of power for operating a drive device through a hose, and

[0053] Preferably, a storage station is provided for storing drive devices ready to be coupled to a ladle sliding gate.

[0054] In a preferred embodiment, a preheating oven is provided to bring a new ladle cover loaded onto the ladle slide gate of a first or second ladle located at a loading station to a preheating temperature and maintain it. This preheating oven may be provided instead of or in addition to a heating storage rack or a separate oven for preheating the new ladle cover before joining it to the ladle.

[0055] In a preferred embodiment, the robot also

[0056] · Check the condition of the used ladle lid after removal from the empty ladles, and

[0057] · Evaluate whether the used ladle cover can be reused after cleaning or must be discarded, and

[0058] Advantageously configured to clean the ladle cover used with an oxygen shower to remove any residue attached to the walls of the used ladle cover.

[0059] The present invention also relates to a molten metal casting method comprising the following steps:

[0060] (a) A step of providing the metal casting facility described above, wherein,

[0061] · The first ladle is filled with molten metal and is located at the casting station,

[0062] · The second ladle is filled with molten metal and is at the loading station,

[0063] · The ladle sliding gate of the first ladle is in a sealed position and is coupled to one or more driving devices or optionally a drawer driving device, and is equipped with a ladle cover and a collector nozzle,

[0064] · Step, in which the ladle sliding gate of the second ladle is in a sealed position, and does not include the ladle cover, the motion drive device, or the motion drawer drive device,

[0065] (b) a step of moving the ladle slide gate of the first ladle to a casting position to cast molten metal from the first ladle through the ladle cover into the tundish,

[0066] (c) During the previous step,

[0067] · Load a new ladle cover into the ladle slide gate of the second ladle using a robot, and

[0068] · A step of combining a driving device with the sliding plate gate of the second ladle using a robot,

[0069] (d) When the first ladle is substantially empty, moving the ladle slide gate of the first ladle to a sealed position, and then,

[0070] (e) a step of moving the first ladle from the casting station to the loading station, and simultaneously moving the second ladle from the loading station to the casting station to swap the positions of the first and second ladles,

[0071] (f) Moving the ladle slide gate of the second ladle to the casting position and casting molten metal from the second ladle through the ladle cover into the tundish.

[0072] In a preferred embodiment, the method comprises the following steps during step (f):

[0073] (g) a step of removing the used ladle cover from the ladle slide gate of the first ladle emptied by a robot and storing the used ladle cover for repair or as waste,

[0074] (h) a step of disengaging and removing one or more driving devices from the sliding plate gate of the first ladle with a robot and storing them for further use,

[0075] (i) a step of removing the emptied first ladle, and

[0076] (j) a step of loading a new ladle filled with molten metal onto a first holding device of a ladle turret at a loading station, wherein, similar to the second ladle of step (a), the new ladle includes a ladle slide gate in a sealed position and does not include a ladle cover.

[0077] In many cases, the opening of the first ladle is filled with a plugging material to prevent the metal from solidifying upon contact with the cold surface of the upper plate of the ladle sliding gate. The plugging material is typically in the form of fine particles. In some cases, some molten metal seeps through the fine particulate plugging material and solidifies to form a solid mass that blocks the opening, preventing any molten metal from flowing out of the opening when the ladle sliding gate of the first ladle is moved to the casting station in step (b). When such a blockage occurs, the opening can be cleared by performing the following steps:

[0078] · Step of moving the ladle slide gate of the first ladle to an unlocked position,

[0079] · A step of using a suitable unclogging tool to break up the plugging material and unclog the opening of the first ladle,

[0080] · A step of moving the ladle slide gate of the first ladle to a casting position to cast molten metal from the first ladle into the tundish through the cleared opening and through the ladle cover when the plugging material begins to flow out from the collector nozzle.

[0081] (e) The step of swapping the positions of the first and second ladles preferably includes the following steps:

[0082] · A step of raising the first and second ladles until the ladle covers of both the first and second ladles fall away from the tundish and become higher than the tundish in the vertical direction (Z),

[0083] · A step of rotating the turret 180° around the vertical axis (Z) to move the first ladle onto the loading station and the second ladle onto the casting station and the tundish,

[0084] · A step of lowering the first and second ladles to their respective loading and casting stations, wherein the ladle cover of the second ladle is inserted into the tundish.

[0085] In a preferred embodiment, the robot also,

[0086] · Check the condition of the used ladle lid after removal from the empty ladles, and

[0087] · Evaluate whether the used ladle cover can be reused after cleaning or must be discarded, and

[0088] · Clean the ladle cover used with an oxygen shower to remove any residue attached to the walls of the used ladle cover. Brief explanation of the drawing

[0089] Figure 1 depicts various steps of replacing the first ladle, which is empty after being dropped from the casting station, with the second ladle, which is full after being prepared at the loading station. FIG. 2 illustrates various steps for unclogging a blocked ladle outlet using a ladle sliding gate according to a first embodiment of the present invention. FIG. 3 illustrates various steps for unclogging a blocked ladle outlet using a ladle sliding gate according to a second embodiment of the present invention. Specific details for implementing the invention

[0090] As illustrated in FIG. 1, a metal casting apparatus according to the present invention comprises a first ladle (11) and a second ladle (12). The first ladle is held at a casting station above the tundish (1) to transfer molten metal (2) contained in the first ladle (11) to the tundish (1). The tundish transfers the molten metal to a tool or mold. In this system, the tundish contains a volume of molten metal that is maintained substantially constant throughout the transfer of molten metal from the first ladle (11) to the tundish (1). When the contents of the first ladle are completely emptied, it must be replaced as quickly as possible with a second ladle (12) that is fully equipped and filled with molten metal to continue transferring the molten metal (2) to the tundish (1), thereby maintaining a substantially constant level of molten metal in the tundish and, at the same time, maintaining a substantially constant flow rate of molten metal from the tundish to the tool or mold.

[0091] The ladle (11, 12) includes a bottom provided with an opening (11o, 12o). An internal nozzle (18) having an internal bore fluidly communicates the internal volume of the tundish with the opening (11o, 12o). The ladle (11, 12) also includes a ladle sliding gate (15) configured to reversibly receive and support a ladle shroud and to be coupled to a driving device (17) for operating the ladle sliding gate between a sealed position where the opening is sealed and a casting position where the opening is fluidly communicated with the ladle shroud (13a-13c).

[0092] The ladle sliding gate (15) of the ladle according to the present invention is also configured to reversibly receive and support the collector nozzles (14a, 14b). The driving device (17) or the drawer driving device (17w) is further configured to operate the ladle sliding device (15) to a clog-free position in which the opening is fluidly in communication with the collector nozzle (14). As described more specifically below, the clog-free position is used when molten metal does not flow out of the ladle when the ladle sliding gate is in the casting position due to a clog.

[0093] To accelerate the exchange between the empty first ladle (11) and the full second ladle (12), the first and second ladles are supported by corresponding first and second holding devices of a rotary turret (30) (see FIG. 1a). The first and second holding devices are fork-shaped arms that hold the first and second ladles (11, 12) at an "arm length" from the central axis of rotation (Z). Rotation of the turret around the central axis of rotation (Z) causes the first and second ladles to move between the following:

[0094] · A casting station in which one of the first or second ladles (11, 12) is held on the tundish with the ladle cover (13a-13c) partially inserted into the tundish, and

[0095] · A loading station, wherein the other of the first or second ladle is equipped at the loading station to prepare for the transfer of molten metal into the tundish when moving to the casting station.

[0096] Because the ladle covers (13a-13c) are partially inserted into the tundish (1), the turret (30) must first raise the first and second ladles to drive the ladle cover (13a) of the first ladle (11) out of the tundish (1) and over it before rotating around the central axis of rotation (Z) so as not to cause the ladle covers of the first and second ladles to collide with the tundish.

[0097] For loading, a loading platform (20) is provided that includes spare parts and tools such as a new ladle cover (13b, 13c), a new collector nozzle (14), or a spare drive device (17). As previously described, the ladle cannot be transported across the workspace between the casting facility and the furnace with the long ladle cover (13a-13c) protruding from its bottom. Consequently, the new ladle filled with molten metal reaches the casting station without the ladle cover (13a-13c). The new ladle (11, 12) filled with molten metal (2) reaches the turret (30) with the ladle sliding gate (15) fixed to the bottom of the ladle but without the drive device (17), and with the collector nozzle (14) attached to the ladle sliding gate. The collector nozzle is very short and can be attached to the ladle and moved across the workspace without any risk of collision. Accordingly, new ladle covers (13a-13c) can be attached to the new ladle (12) when the new ladle is docked to the turret (30) of the loading station. At the same time, the drive device (17) must be attached to the ladle (11, 12) and the ladle slide gate (15) and activated by being connected to a source of pressurized fluid for the hydraulic or pneumatic drive device (17) or a power source for the electric drive device (17).

[0098] Rather than having a human operator perform these operations manually, the present invention proposes providing a robot (21) on or adjacent to a loading platform (20). The robot (21) is configured to load a new ladle cover (13b) onto a ladle sliding gate (15) and to engage a drive device (17) with the ladle sliding gate (15).

[0099] Casting equipment

[0100] FIG. 1 illustrates various steps of a continuous casting operation having an apparatus according to the present invention. The replacement of an empty first ladle (11) and a filled second ladle (12) is described in more detail in the following section. FIG. 1a illustrates a turret (30) comprising first and second holding devices for securing the first and second ladles (11, 12). The turret is positioned adjacent to a tundish, and thus, each of the first and second holding devices can move the ladles (11, 12) to a casting station, and the ladle covers are partially inserted into the tundish below the level of molten metal contained in the tundish while in use in a stationary state. FIG. 1a illustrates this configuration with a first ladle (11) partially filled with molten metal held in the casting station by the first holding device of the turret (30). The first ladle is placed on the tundish (1) with the ladle nozzles (13a-13c) partially inserted into the tundish and partially immersed below the level of molten metal contained in the tundish. The ladle sliding gate (15) of the first ladle (11) is coupled to a drive device (17) configured to move the plate of the sliding gate between the previously described sealing, casting, and unclogging positions. In the embodiment of FIG. 1, the drive device (17) is a hydraulic piston connected to a source (17h) of pressurized fluid through a tune (17t). The drive device (17) may be pneumatic or electric, but a hydraulic drive device is preferred.

[0101] A second ladle (12) filled with molten metal coming directly from the furnace is held at the loading station by the second holding device of the turret (30) at the loading station within the robot reach of the loading platform (20). The ladle slide gate (15) of the second ladle (12) is in a sealed position. Unlike the first ladle (11), the second ladle (12) is not ready to cast molten metal because it has no ladle cover (13b) and no drive device (17). It is possible to pre-mount a drive device (17) on the second ladle (12), but it is not in an operational state because it will not be connected to any pressurized fluid source for hydraulic and pneumatic drive devices or any power source for electric drive devices. Generally, when it reaches the turret, the second ladle (12) has no drive device (17), and in the few cases where a drive device is provided, the drive device does not operate.

[0102] The loading platform (20) includes a storage rack (29) having various tools (not shown) necessary for preparing the second ladle (12) for casting and a spare ladle cover (13b, 13c). The front ladle cover (13a, 13c) for joining to the ladle is preferably preheated in the storage rack (29) or in a separate oven within the reach of the robot to prevent any severe thermal shock when molten metal flows through the ladle cover when starting the casting operation at the casting station. In some cases, the platform may include a spare drive device (17) and, if possible, a spare collector nozzle (14), but the collector nozzle (14) is preferably joined to the second ladle at a separate repair station before filling the ladle with molten metal from the furnace.

[0103] The drive device (17) for operating the ladle slide gate (15) of the second ladle (12) and optionally the drawer drive device (17w) (defined below for the first embodiment illustrated in FIG. 2) are preferably stored on or near the second holding device of the turret (30). It is preferable to store the drive device on the first and second holding devices because it is most convenient for the pressurized fluid source (17h) to also be located on or near the first and second holding devices as shown in FIG. 1a, so that in this way, there is no need to connect and disconnect the (drawer) drive device whenever it is coupled to and removed from the ladle.

[0104] FIG. 1b illustrates that while the first ladle (11) discharges the contents of the molten metal into the tundish, the robot (21) removes a new ladle cover (13b) from the storage rack (29) and attaches the new ladle cover to the ladle slide gate (15) of the second ladle (12), which maintains a sealed position throughout the second ladle's stay at the loading station. As previously described, in a preferred embodiment, the new ladle cover (13b) is heated to a preheating temperature in a separate oven within the reach of the storage rack (29) or the robot (21) before being loaded into the ladle slide gate. Preheating the ladle cover before casting reduces the risk of cracking due to severe thermal shock when the molten metal begins to flow through the ladle cover at the start of the casting operation. Since the second ladle (12) equipped with a new ladle cover (13b) may remain at the loading station for a certain period of time while waiting for the first ladle (11) to be emptied before being moved to the casting station, the new ladle cover (13b) has time to cool down, thereby losing all benefits of the preheating operation. For this reason, in the preferred embodiment of the invention illustrated in FIG. 1c, in addition to or alternative to preheating the new ladle cover in a storage rack or a separate oven, a preheating oven (25) is provided at the loading station to maintain the new ladle cover (13b) loaded at the ladle slide gate (15) of the second ladle (12) located at the loading station at a preheating temperature (optional). By using this preheating oven (25), the ladle cover arrives at the casting station at the required preheating temperature and casting can begin with a low risk of cracking due to thermal shock. The preheating oven (25) may be movably coupled to the loading platform (20) or the first and second holding devices of the turret. It is preferably in the form of an open book that is closed over a new ladle cover (13b) when loaded into the ladle slide gate (15).The robot (21) can handle the oven to move it to a preheating position.

[0105] The robot (21) can preferably move along a horizontal plane (X, Y) and has multiple degrees of freedom, preferably at least 5 or at least 7 degrees of freedom. The robot must be capable of both reaching a storage rack (29) to collect or store tools and / or casting components and reaching a ladle sliding gate (15) of a ladle that remains at a loading station. There must be sufficient degrees of freedom to perform all connecting and disconnecting, and connecting and unconnecting, necessary to ensure continuous casting operations of the casting facility.

[0106] In particular, as illustrated in FIGS. 1b and 1c, the robot must be configured to engage (disengage) the ladle cover (13a-13c) and the (drawer) drive device (17, 17w), and to engage (disengage) the hose (17t) to (from) the (drawer) drive device (17, 17w). In FIG. 1, the first and second holding devices of the turret (30) have both of the following:

[0107] · A storage station for storing one or more (drawer) drive devices (17, 17w), and

[0108] · A pressurized fluid source connected to one or more (drawer) drive devices to operate the ladle slide gate (15).

[0109] In this configuration, the robot (21) only needs to collect the drive device (17) from the storage station at the second holding device and connect it to the ladle and ladle sliding gate (15). When the drive device is stored in the storage rack (29) or when the drive device stored in the storage station needs to be replaced with a new one stored in the storage rack (29), in addition to connecting one or more (drawer) drive devices (17, 17w) to the ladle and ladle sliding gate (15), the robot (21) also needs to connect one or more hoses (17t) to the corresponding (drawer) drive device to operate the drive device to operate the ladle sliding gate.

[0110] As illustrated in FIG. 1d, when the first ladle (11) is substantially empty, it must be replaced with a full second ladle (12) waiting to be loaded. In the embodiment illustrated in FIG. 1, the turret (30) is configured to raise the first and second ladles (11, 12) to a rotational height, ensuring that the ladle covers (13a, 13b) of the first and second ladles do not collide with any other element of the tundish (1) or casting facility during rotation of the turret. As illustrated in FIG. 1e, the turret (30) is also configured to rotate around a vertical axis (Z) to switch the positions of the first and second ladles in a single movement, for example, while still maintaining a rotational height above their respective loading and casting positions. Finally, the turret (30) must be configured to lower both the first and second ladles to their corresponding loading and casting stations, as illustrated in FIG. 1f.

[0111] The movement of the ladle slide gate (15) of both the first and second ladles and the movement of the turret must be perfectly synchronized to prevent any unwanted dripping or flow of molten metal from either of the first or second ladles.

[0112] The robot (21) must also be configured to remove the emptied first ladle (11), ladle cover (13a), and drive device (17) located at the loading station. The used ladle cover (13a) may be stored for cleaning and further use or disposed of in a waste container (27). The drive device (17) may be stored at the storage station on the first holding device of the turret (30) without needing to be separated from the pressurized fluid source, or may be stored in the storage rack (29) of the loading platform after the pressurized fluid source is separated from it. The emptied first ladle (11), stripped of both the ladle cover (13a) and the drive device (17), may now be removed to a service station for repair. A new ladle filled with molten metal may be moved from the furnace to begin the full operation as illustrated in FIGS. 1a through 1f described above and loaded onto the now empty first holding device of the turret.

[0113] Robot (21)

[0114] The robot (21) may have at least five, preferably at least six or seven degrees of freedom. The robot is preferably movably mounted on a loading platform (20) so that the robot can translate parallel to a first axis (X) and / or a second axis (Y) perpendicular to the first axis (X), or a combination thereof. The robot (21) may preferably rotate around a vertical axis (Z) perpendicular to the first and second axes (X, Y). With this combination of movement, the robot must be able to reach and retrieve any tool or component from a storage rack (29) and reach the ladle slide gate (15) of a first or second ladle (11, 12) held at a loading station to perform the operation described below. Excellent results were obtained using the Kuka Foundry type Robot KR480.

[0115] The robot is configured to attach a ladle cover (13a-13c) and a drive device (17) to a ladle (11, 12) filled with molten metal and the ladle slide gate (15). It is also configured to remove a used ladle cover (13a-13c) and a drive device (17) from a first or second ladle (11, 12) that has been emptied and held at a loading station after being moved from a casting station. To avoid severe thermal shock, the ladle cover (13b) is preferably stored at a preheating station before being attached to the ladle slide gate (15) of the ladle at the loading station. The robot can handle the ladle cover from a storage rack (29) to a preheating station (not shown) and there to be attached to the ladle slide gate (15). Similarly, to remove the ladle cover from the emptied first ladle (11), the robot may remove it and move it to a pressurized gas (e.g., oxygen) cleaning station (not shown) and a preheating station or to a storage rack (29) for further use. Alternatively, the robot may discard the ladle cover into a waste container (27) if it is worn out too much to be used further.

[0116] The robot is also configured to check the condition of the used ladle covers (13a-13c) after they have been removed from the emptied ladle. In a preferred embodiment, the robot is configured to evaluate whether the used ladle covers can be reused or must be discarded after cleaning. This can be achieved by programming the robot's artificial intelligence to "learn" to distinguish between used ladle covers that can be reused and those that must be discarded. The robot is also preferably configured to clean the used ladle covers, advantageously with an oxygen shower, to remove any residue attached to the walls of the used ladle covers.

[0117] Ladle sliding gate (15)

[0118] A ladle sliding gate (15) suitable for the present invention comprises an upper plate (15u) and a lower plate (15d). The upper plate comprises a fixed surface and a lower sliding surface separated from each other by the thickness of the upper plate, and an upper bore extending from the fixed surface to the lower sliding surface. The fixed surface of the upper plate is rigidly fixed to the lower portion of the corresponding first or second ladle (11, 12) in a state where the upper bore is in fluid communication with the opening (11o, 12o). The opening is generally formed by the downstream end of the inner bore of the inner nozzle (18), as illustrated in FIG. 2a and FIG. 3a. During the entire casting operation from the ladle (11, 12) to the tundish (1), the upper plate (15u) is fixed to the opening (11o, 12o) and the inner nozzle (18).

[0119] The lower plate (15d) includes a nozzle sliding surface and an upper sliding surface separated from each other by the thickness of the lower plate, and one or two lower bores extending from the upper sliding surface to the nozzle sliding surface. The lower plate (15d) is slidably mounted so that the upper sliding surface can slide translationally along the lower sliding surface so that the one or two lower bores enter and exit a fluid communication state with the upper bores. The lower plate can be moved translationally by operating a drive device (17). The drive device may include a cylinder (17c) rigidly and reversibly coupled to the lower portion of the first or second ladle (11, 12) and a piston (17p) reversibly fixed to the lower plate (15d). For example, the drive device (17) may be a hydraulic piston or a pneumatic piston.

[0120] In the first embodiment illustrated in FIG. 2, the lower plate (15d) comprises only one lower bore. The ladle sliding gate of this embodiment comprises a drawer (15w) configured to rigidly hold the ladle cover (13a-13c) and the collector nozzle (14) side by side. The ladle cover has a cover bore that opens upstream at the upper cover surface and downstream at the lower cover end. Similarly, the collector nozzle (14) has a collector bore that opens upstream at the upper collector surface and downstream at the lower collector end. As is well known in the art, the collector nozzle is substantially shorter than the ladle cover, and thus, when the ladle is in the casting position, the lower collector end is well separated from the tundish and can be easily accessed with a clearing tool (19r), such as a staff or a pressurized gas lance. The drawer, for example, along the nozzle sliding surface of the lower plate (15d), the upper cover surface and the collector surface

[0121] · Cover position where the cover bore is in fluid communication with the lower bore,

[0122] · A collector location where the collector bore is in fluid communication with the lower bore, and preferably

[0123] · It is movably mounted to translate between a sealed position where the downstream end of the lower bore is sealed and does not fluidly communicate with either the ladle bore or the collector bore.

[0124] A sealed position of the drawer (15w) is desirable but not essential, because flow from the ladle can be stopped by moving the lower bore of the lower plate out of alignment with the upper bore of the upper plate. The drawer (15w) can be translated by operating the drawer drive device (17w), similar to the lower plate. The drawer drive device may include a cylinder (17c) that is rigidly and reversibly coupled to the bottom portion of the first or second ladle (11, 12) and a piston (17p) that is reversibly fixed to the drawer (15w). For example, the drawer drive device (17w) may be a hydraulic piston or a pneumatic piston. When the drawer drive device (17w) is operated, the drawer (15w) can be moved to cause the cover bore and the collector bore to enter and exit alignment with the lower bore.

[0125] FIGS. 2a through 2d illustrate various steps for initiating a casting operation from a ladle (11, 12) to a tundish (1) using a ladle sliding gate according to the first embodiment. FIG. 2a illustrates a new ladle (11, 12) that has reached the casting station. The ladle sliding gate is in a sealed position where the lower bore of the lower plate (15d) is outside the mating state from the upper bore of the upper plate (15u). The inner bore and upper bore of the inner nozzle (18) are filled with a plugging material (19), which may be sand or any other particulate material to prevent freezing of the sliding mechanism by solidified metal. The drawer (15w) may be positioned in a covered position where the cover bore is in fluid communication with the lower bore. No metal can flow through the ladle because the downstream end of the upper bore is sealed by the lower plate. In this application, upstream and downstream are defined according to the intended flow direction of the molten metal. When the ladle arrives at the casting station, casting can begin.

[0126] As illustrated in FIG. 2b, to initiate casting, the driving device (17) fluidly connects the lower bore and the ladle bore with the upper bore, thereby translating the lower plate and the ladle cover until a continuous flow channel is formed from the inner bore to the cover bore. Under normal conditions, the plugging material (19) is driven by the pressure of the molten metal in the ladle and flows out through the lower bore and the cover bore. When the plugging material (19) is discharged, the molten metal flows out of the ladle through the cover bore. This operation takes a few seconds, and casting from the tundish to the tool can proceed continuously. However, in some cases, the plugging material may form a solidified mass as the molten metal seeps through it and solidifies, forming a binder between the particles of the plugging material (19). Depending on the size and resistance of this solidified mass, this may cause blockage of the inner bore and the upper bore, preventing the molten metal from flowing out of the ladle. This situation is more exceptional than usual, but in such cases, it causes serious problems with the casting operation. For this reason, many workers are reluctant to secure the ladle cover (13a-13c) to the ladle sliding gate (15) and prefer to use a robot to hold the ladle cover in place when the ladle is at the casting station. By using the ladle sliding gate (15) according to the present embodiment, the clogged inner bore and / or upper bore can be unclogged very quickly even with the ladle cover (13a-13c) secured to the drawer (15w).

[0127] As illustrated in FIG. 2c, the drawer drive device (17w) translates the drawer (15w) so that, for example, the collector nozzle (14) is in fluid communication with the lower bore and the upper bore. Since the collector nozzle is substantially shorter than the ladle cover, leaving sufficient space over the tundish, a clearing tool (19r) can be easily introduced through the downstream end of the collector nozzle, through the lower and upper bores, and into the inner bore. The clearing tool may be a metal staff that can be used to strike the solidified plugging material to break up the solidified mass. Alternatively, the clearing tool (19r) may be a pressurized gas lance that projects a jet of pressurized gas, such as oxygen. The clearing tool (19r) may be handled manually or by a robot.

[0128] As soon as the solid mass is destroyed, particles of the plugging material (19) begin to flow out through the collector nozzle, and as illustrated in FIG. 2d, casting can begin normally. The drawer (15w) can be translated to fluidly communicate, for example, with the ladle bore, the upper bore, and the inner bore to start the casting operation. If the drawer includes a sealing position as previously defined between the collector position and the ladle position, then the lower plate (15d) does not need to be moved when translating the drawer (15w). Otherwise, the lower plate (15d) can be moved to the sealing position before moving the drawer between the collector position and the ladle position.

[0129] In the second embodiment illustrated in FIGS. 3a through 3d, the lower plate (15d) comprises a first bore and a second bore, each of which extends from an upper sliding surface to a nozzle sliding surface. The lower plate (15d) is slidably mounted so that the upper sliding surface can slide along the lower sliding surface to allow each of the first and second bores to enter and exit a fluid communication state with the upper bore. The nozzle surface is configured to be rigidly and reversibly coupled to the ladle cover (13a-13c) in a state where the ladle bore is fluidly communicating with the first bore and the collector bore is fluidly communicating with the second bore. Ladle cover (13a-13c) and collector nozzle. The nozzle sliding surface of the lower plate (15d) in this second embodiment does not have any sliding function. During the entire casting operation from the ladle (11, 12) to the tundish (1), the ladle cover (13a-13c) and the collector nozzle (14) are fixed to the lower plate (15d) and maintained in a matched state with the first and second bores, respectively.

[0130] FIGS. 3a through 3d illustrate various steps for initiating a casting operation from a ladle (11, 12) to a tundish (1) using a ladle sliding gate according to a second embodiment. FIG. 3a illustrates a new ladle (11, 12) that has reached the casting station. The ladle sliding gate is in a sealed position where both the first and second bores of the lower plate (15d) are outside the mating state from the upper bore of the upper plate (15u). As in the first embodiment, the inner bore and the upper bore of the inner nozzle (18) are filled with a plugging material (19), which may be sand or any other particulate material to prevent freezing of the sliding mechanism by solidified metal. Neither the molten metal (2) nor the plugging material (19) is allowed to flow through the ladle, because the downstream end of the upper bore is sealed by the lower plate. When the ladle arrives at the casting station, casting can begin.

[0131] As illustrated in FIG. 3b, to start casting, the driving device (17) fluidly connects the first bore and the ladle bore with the upper bore and thus translates the lower plate and the ladle cover (13a-13c) until a continuous flow channel is formed from the inner bore to the cover bore. Under normal conditions, the plugging material (19) is driven by the pressure of the molten metal in the ladle and flows out through the lower bore and the cover bore. When the plugging material (19) is discharged, the molten metal flows out of the ladle through the cover bore. This operation takes a few seconds, and casting from the tundish to the tool can proceed continuously. However, as described in the first embodiment, in some cases, solidified lumps of the plugging material (19) may block the inner and upper bores, and thus, no molten metal can flow out of the ladle, and the passage must be cleared. By using the ladle sliding gate (15) according to the present embodiment, the blocked inner bore and / or upper bore can be unblocked very quickly even when the ladle cover (13a-13c) is fixed to the lower plate (15d) as follows.

[0132] As illustrated in FIG. 3c, the driving device (17) translates the lower plate (15d) so that, for example, the second bore and the collector nozzle (14) are fluidly connected to the upper bore. Since the collector nozzle is substantially shorter than the ladle cover, it leaves sufficient space over the tundish, and a clearing tool (19r) can be easily introduced through the downstream end of the collector nozzle, through the lower and upper bores, and into the inner bore. The clearing tool may be a metal staff or a pressurized gas lance and may be used to clear the passage as described in relation to the first embodiment. The clearing tool (19r) may be handled manually or by a robot.

[0133] As soon as the solid mass is destroyed, particles of the plugging material (19) begin to flow out through the collector nozzle, and as shown in FIG. 3d, casting can begin normally. The lower plate (15d) can be translated, for example, so that the first bore and ladle bore are in fluid communication with the upper bore and inner bore to start the casting operation.

[0134] In all embodiments of the ladle slide gate (15), the drive device (17) may be operated hydraulically, pneumatically, or electrically. At least one first holding device and at least one second holding device of the ladle turret are provided with a pressurized fluid source to operate the drive device (17), and, if a drawer (15w) is included, to operate the drawer drive device (17w) through a hose (17t). In a preferred embodiment, at least one first holding device and at least one second holding device of the ladle turret also include a storage unit for storing the drive device (17) and, if a drawer (15w) is present, a storage unit for storing the drawer drive device (17w) when the (drawer) drive device (17) is not coupled to the ladle slide gate (15) as shown in FIG. 1a, FIG. 1b and FIG. 1f. The (drawer) casting device (17, 17w) may also be stored in a storage rack of the loading platform. However, since the drive device (17, 17w) can be permanently connected to a source of hydraulic or pneumatic fluid (17h) through a hose (17t) in this manner, it is preferable to store them in the first and second holding devices. This allows the robot (2&), which would otherwise have to perform the complex operation of connecting the hose (17t) to the newly connected drive device (17, 17w) when the drive device (17, 17w) is stored in the storage rack (29) of the loading platform, to avoid performing the complex operation.

[0135] Molten metal casting method

[0136] The present invention also relates to a method for casting molten metal (2) from ladles (11, 12) into a tundish (1) in a casting facility as previously described, wherein the first ladle (11) is filled with molten metal and is located at a metal and casting station, and the second ladle (12) is filled with molten metal and is located at a loading station. As illustrated in FIG. 1a, the ladle sliding gate (15) of the first ladle (11) is in a sealed position and is equipped with a ladle cover (13a-13c) and a collector nozzle (14). The lower plate (15d) of the ladle sliding gate is coupled to a drive device (17). If the ladle sliding gate (15) is of the type described for the first embodiment that includes a drawer (15w), the drawer is coupled to a drawer drive device (17w). The ladle sliding gate (15) of the second ladle (12) is in a sealed position and does not include a ladle cover. The ladle sliding gate (15) of the second ladle (12) is not coupled to any (drawer) drive device (17, 17w).

[0137] To begin casting molten metal from the first ladle (11) into the tundish (2) through the ladle cover (13a), the ladle slide gate (15) of the first ladle (11) is moved to the casting position. This operation is performed by operating the drive device (17). The first ladle (11) discharges the molten metal (2) contained therein into the tundish (1) until the first ladle is considered to be empty.

[0138] As the first ladle (11) discharges its contents into the tundish, the robot (21) loads a new ladle cover (13b) into the ladle slide gate (15) of the second ladle (12) (see FIG. 1b). As illustrated in FIG. 1c, the robot (21) also connects the drive device (17) and optionally the drawer drive device (17w) to the slide plate gate (15) of the second ladle (12). As previously described, this operation is simplified if the first and second holding devices of the turret (30) are provided with a storage unit for storing one or more (drawer) drive devices (17, 17w), because, accordingly, one or more (drawer) devices can remain connected to a source of pressurized fluid (17h) through a hose (17t) during the entire casting operation involving emptying several (more than two) ladles into the tundish. If one or more (drawer) drive devices (17, 17w) are stored elsewhere, typically in a storage rack (29) located on a loading platform (20), the robot (21) must additionally connect one or more hoses (17t) to the corresponding one or more (drawer) drive devices so that they can be operated. During the entire operation for the second ladle (12), the ladle slide gate is maintained in a sealed position.

[0139] As illustrated in FIG. 1d, when the first ladle is substantially empty, the ladle slide gate (15) of the first ladle (11) is moved from the casting position to the sealing position to block any flow of molten metal out of the first ladle (11). The positions of the first and second ladles are swapped by moving the first ladle (11) from the casting station to the loading station, and simultaneously, moving the second ladle (12) from the loading station to the casting station. The swapping of the positions of the first and second ladles (11, 12) can be performed as follows. FIG. 1d illustrates how the turret (30) can raise the first and second ladles (11, 12) until the ladle covers (13a, 13b) of both the first and second ladles are separated from the tundish and are higher than the tundish in the vertical direction (Z) to form a rotational height. Accordingly, the turret can rotate without any risk of the ladle covers (13a, 13b) of the first or second ladle (11, 12) colliding with any other component of the tundish or casting facility. FIG. 1e illustrates a rotation of the turret by 180° around a vertical axis (Z) to move the empty first ladle (11) over the loading station, the filled second ladle (12) over the casting station, and over the tundish (2). During the rotation operation, the first and second ladles are maintained at a constant rotational height. At this stage, the first and second ladles (11, 12) can be lowered to their respective loading and casting stations, and the ladle cover (13b) of the second ladle is inserted into the tundish (2).

[0140] The ladle slide gate (15) of the second ladle (12) can be moved to a casting position so that molten metal can flow from the second ladle (12) through the ladle cover (13b) to the tundish (2). The entire replacement operation from closing the ladle slide gate of the first ladle (11) to opening the ladle slide gate of the second ladle (12) can last for less than 2 minutes, preferably less than 1 minute, more preferably less than 30 seconds, and the molten metal level in the tundish can be easily restored to a fixed casting level.

[0141] The emptied first ladle (11) parked at the loading station now has its ladle cover removed so that it can be removed and transported across the workshop to a repair station (not shown). The used ladle cover (11a) can be removed from the ladle slide gate (15) of the emptied first ladle (11) by a robot (21). The used ladle cover (13a) can be stored for repair and cleaning (not shown) or as waste in a waste container (27) as shown in FIG. 1f.

[0142] As illustrated in FIG. 1f, the robot (21) may also detach and remove one or more (drawer) drive devices (17, 17w) from the sliding plate gate (15) of the first ladle (11) and store them for further use. If the first and second holding devices of the turret (30) are equipped with a storage unit for storing one or more (drawer) drive devices (17, 17w), then the robot (21) does not need to detach one or more corresponding hoses (17t) before storing them, because a source of hydraulic or pneumatic fluid (17h) or a power source is also located in the first and second holding devices. On the other hand, if one or more drive devices (17, 17w) are stored in a storage rack (29) located on a loading platform (20), then the robot must also detach one or more hoses (17t) from the corresponding one or more (drawer) drive devices (17, 17w) before storing them in the storage rack (29). This applies equally if the (drawer) drive device needs to be changed due to a defect.

[0143] The first empty ladle, with the ladle cover (13a) and one or more (drawer) drive means (17, 17w) removed, can be removed from the first holding device by a crane to a repair station (not shown), where the ladle can be cleaned, repaired, and prepared to be filled with a load of new molten metal from the furnace. The new ladle filled with molten metal can be loaded onto the now empty first holding device of the ladle turret (30) at the loading station, where, similar to the second ladle (12) of step (a), the new ladle includes a ladle slide gate (15) in a sealed position and does not include the ladle cover (13a-13c) or the (drawer) drive means (17, 17w). Accordingly, the cycles illustrated in FIGS. 1a through 1f can be repeated, and casting from the tundish to the tool can proceed continuously, and the level of molten metal in the tundish is substantially constant throughout the continuous casting operation with almost no variation when switching the positions of the empty ladle (11) and the filled ladle (12) defined in step (e). Since the switching operation is very rapid when functioning optimally, the variation may be very small.

[0144] In cases where the step (e) of swapping the positions of the first and second ladles does not proceed optimally because the inner and / or upper bore is blocked by solidified plugging material, the use of a ladle sliding gate (15) containing both the ladle cover (13a-13c) and the collector nozzle (14) side by side enables rapid and efficient clearing of the inner and / or upper bore by using a suitable clearing tool (19r) through the collector bore, as previously described in the "Ladle Sliding Gate (15)" section. In this way, the interruption of metal flow into the tundish is reduced to a minimum. Without the option for rapid unclogging through the collector bore, many workers, whether or not they have a robot (21), would be reluctant to secure the ladle cover (13a-13c) to the bottom of the ladle at the loading station, because unclogging the inner and upper bores while the ladle cover is secured to the ladle sliding gate would require returning the clogged ladle to the loading station, replacing the ladle cover with a collector nozzle to enable unclogging using a unclogging tool (19r), and then reassembling the ladle cover and moving the ladle back to the casting station. All of these operations would take too long, along with the risk of metal freezing, which has been prevented by the use of plugging materials. Furthermore, if molten metal is not supplied to the tundish for a long period, it would cause a interruption in the casting operation, which must be avoided at all costs.

[0145] In a preferred embodiment, the loading operation of the second ladle (12) located at the loading station is performed in the following order: (1) the drive device(s) (drawer) is attached to the ladle sliding gate (15), and then the new ladle cover (13b) is attached. The unloading operation of the empty first ladle (11) placed at the loading station is preferably performed in the following order: (1) the used ladle cover (13b) is removed, and then the drive device (drawer) is removed from the ladle sliding gate (15).

[0146] The present invention provides an automated metal casting facility, wherein the new ladle can be prepared for casting by a robot (21) at a loading station without any additional risk of interruption of casting to the tool compared to a conventional metal casting facility. Explanation of the symbols

[0147] 1 tundish 2 Molten metal 3 Casting Tools 5 Tundish Runway Gate 11 1st Ladle 11o Opening of the first ladle 12 2nd Ladle 12o Opening of the second ladle 13a-13c Collector Nozzles 14 Ladle Cover 15 Ladle Runway Gate 15d Lower plate of ladle sliding gate Upper plate of the 15u ladle sliding gate 15w drawer 17 Driving Devices 17c cylinder 17h Hydraulic / Pneumatic Fluid Source 17p Piston 17t hose 17W drawer drive device 18 internal nozzles 19 Plugging material 19r Unblocking stick 20 Loading Platforms 21 robots Preheat oven to 25 27 waste containers 29 storage racks 30 Ladle Turrets

Claims

Claim 1 In a metal casting facility, (a) a loading platform (20), (b) a tundish (1), (c) a first ladle (11) and a second ladle (12), wherein each of the first and second ladles comprises: a bottom having an opening (11o, 12o), a collector nozzle (14) and a ladle cover (13a-13c), and a ladle sliding gate (15); and (d) a ladle turret (30) comprising at least a first holding device and a second holding device for holding the first ladle (11) and the second ladle (12), respectively, wherein the ladle turret moves and holds the first and second ladles (11, 12) in place between a loading station adjacent to the loading platform (20) and a casting station on the tundish (1). A metal casting facility comprising a ladle turret (30) configured such that the ladle sliding gate is configured to reversibly receive and support the collector nozzle and the ladle cover, and is further configured to be coupled to a drive device (17) for operating the ladle sliding gate between a sealing position where the opening is sealed, a casting position where the opening is fluidly in communication with the ladle cover (13a-13c), and a clearing position where the opening is fluidly in communication with the collector nozzle (14); and the metal casting facility comprises a robot (21) configured to perform the following operations with respect to the first or second ladle (11, 12) held at the loading station: · loading a new ladle cover (13b) into the ladle sliding gate (15), and · coupling the drive device (17) to the ladle sliding gate (15), wherein the robot (21) is located on or adjacent to the loading platform (20). Claim 2 A metal casting facility according to claim 1, wherein the loading platform (20) comprises a tool storage rack (29), the tool storage rack comprises one or more spare ladle covers (13b, 13c) within the reach of the robot (21), and one or more drive devices (17), spare collector nozzles (14), or both. Claim 3 A metal casting facility according to claim 2, wherein the robot (21) is movably mounted on the loading platform (20) so that the robot can translate parallel to a first axis (X), a second axis (Y) perpendicular to the first axis (X), or a combination thereof, or rotate around a vertical axis (Z) perpendicular to the first and second axes (X, Y), to reach and retrieve any tool or component from the tool storage rack (29), and to reach the ladle sliding gate of the first or second ladle (11, 12) held in the loading station to perform the operation of loading the new ladle cover (13b) into the ladle sliding gate (15) and the operation of coupling the drive device (17) to the ladle sliding gate (15). Claim 4 A metal casting facility according to any one of claims 1 to 3, wherein the robot (21) is configured to remove the ladle cover (13a-13c) and the driving device (17) from the empty first or second ladle (11, 12) held in the loading station after being moved from the casting station. Claim 5 In any one of claims 1 to 3, the ladle sliding gate (15) comprises: (a) an upper plate (15u) comprising: a fixed surface and a lower sliding surface separated from each other by the thickness of the upper plate; and an upper bore extending from the fixed surface to the lower sliding surface, wherein the fixed surface of the upper plate is rigidly fixed to the lower portion of a first or second ladle (11, 12) corresponding to a state in which the upper bore is in fluid communication with the opening; and (b) a lower plate (15d) comprising: a nozzle sliding surface and an upper sliding surface separated from each other by the thickness of the lower plate; and a lower bore extending from the upper sliding surface to the nozzle sliding surface, wherein the lower plate (15d) is slidably mounted so that the upper sliding surface can slide translationally along the lower sliding surface, thereby allowing the lower bore to enter and exit a state in fluid communication with the upper bore. A plate (15d), (c) a drawer (15w) configured to rigidly hold a ladle cover (13a-13c) having a cover bore opening on an upper cover surface and a collector nozzle (14) having a collector bore opening on an upper collector surface, wherein the drawer is movably mounted to translate the upper cover surface and the collector surface along the nozzle sliding surface of the lower plate (15d) between a cover position where the cover bore is fluidly in communication with the lower bore and a collector position where the collector bore is fluidly in communication with the lower bore, (d) a driving device (17) coupled to the lower plate (15d) to drive the translation of the lower plate, and (e) a drawer driving device (17w) coupled to the drawer (15w) to drive the translation of the drawer, wherein the driving device (17) is coupled to the lower plate (15d) and a corresponding first or second ladle (11,A metal casting apparatus comprising a cylinder (17c) rigidly and reversibly coupled to the bottom portion of 12) and a piston (17p) rigidly and reversibly fixed to the lower plate (15d), wherein the driving device is configured to move the lower plate so as to cause the lower bore to enter and exit a state of alignment with the upper bore, and the drawer driving device (17w) is coupled to the drawer (15w) and comprises a cylinder (17c) rigidly and reversibly coupled to the bottom portion of the corresponding first or second ladle (11, 12) and a piston (17p) rigidly and reversibly fixed to the drawer (15w), and wherein the drawer driving device is configured to move the drawer so as to cause the cover bore and the collector bore to enter and exit a state of alignment with the lower bore. Claim 6 In any one of claims 1 to 3, the ladle sliding gate (15) comprises: (a) an upper plate (15u) comprising: a fixed surface and a lower sliding surface separated from each other by the thickness of the upper plate; an upper bore extending from the fixed surface to the lower sliding surface; and the fixed surface of the upper plate being rigidly fixed to the lower portion of a first or second ladle (11, 12) corresponding to a state in which the upper bore is in fluid communication with the opening; (b) a lower plate (15d) comprising: a nozzle surface and an upper sliding surface separated from each other by the thickness of the lower plate; and a first bore and a second bore each extending from the upper sliding surface to the nozzle surface; and the lower plate (15d) being slidably mounted so that the upper sliding surface can slide along the lower sliding surface, thereby allowing each of the first and second bores to enter and exit a state in fluid communication with the upper bore, and the nozzle surface A metal casting apparatus comprising a lower plate (15d) configured to be rigidly and reversibly coupled to the ladle cover (13a-13c) having a ladle bore in fluid communication with the first bore and the collector nozzle having a collector bore in fluid communication with the second bore, wherein the driving device (17) comprises a cylinder (17c) coupled to the lower plate (15d) and rigidly and reversibly coupled to the bottom portion of the corresponding first or second ladle (11, 12), and a piston (17p) rigidly and reversibly fixed to the lower plate (15d), and wherein the driving device is configured to move the lower plate to cause the first and second bores to enter and exit a state of alignment with the upper bore. Claim 7 A metal casting facility according to any one of claims 1 to 3, wherein the driving device (17) is operated hydraulically, pneumatically, or electrically, and each of the at least first holding device and second holding device of the ladle turret comprises: a source of pressurized fluid or a power source for operating the driving device (17) through a hose (17t); and a storage station for storing the driving device (17) ready to be coupled to the ladle sliding gate. Claim 8 A metal casting facility according to any one of claims 1 to 3, comprising a preheating oven (25) for bringing a new ladle cover (13b) loaded into the ladle slide gate (15) of the first or second ladle (12) located at the loading station to a preheating temperature and maintaining it. Claim 9 A metal casting facility according to any one of claims 1 to 3, wherein the robot is also configured to: · check the condition of a used ladle cover (13a-13c) after removal from an empty ladle; · evaluate whether the used ladle cover can be reused after cleaning or must be discarded; and · clean the used ladle cover with an oxygen shower to remove any residue attached to the wall of the used ladle cover. Claim 10 A method for casting molten metal, comprising: (a) providing a metal casting facility according to any one of claims 1 to 3, wherein: · the first ladle is filled with molten metal (2) and is located at the casting station; · the second ladle (12) is filled with molten metal (2) and is located at the loading station; · the ladle sliding gate (15) of the first ladle (11) is located at the sealing position and is coupled to one or more driving devices (17) or optionally a drawer driving device (17w), and is equipped with a ladle cover (13a-13c) and a collector nozzle (14); · the ladle sliding gate (15) of the second ladle (12) is located at the sealing position and does not include the ladle cover (13a-13c), the driving device (17), or the driving drawer driving device (17w); (b) the ladle sliding of the first ladle (11). (c) moving the gate (15) from the first ladle (11) to a casting position for casting molten metal into the tundish (1) through the ladle cover (13a); (c) during the previous step, loading a new ladle cover (13b) onto the ladle sliding gate (15) of the second ladle (12) by the robot (21); and (d) attaching the drive device (17) to the ladle sliding gate (15) of the second ladle (12) by the robot (21); (d) moving the ladle sliding gate (15) of the first ladle (11) to a sealing position when the first ladle is substantially empty; then, (e) moving the first ladle (11) from the casting station to the loading station, and simultaneously, moving the second ladle (12) from the loading station to the casting station to swap the positions of the first and second ladles; (f) the second Move the ladle sliding gate (15) of the ladle (12) to the casting position, andA method comprising the step of casting molten metal from the second ladle (12) to the tundish (1) through the ladle cover (13b). Claim 11 A method according to claim 10, wherein during step (f), (g) removing the used ladle cover (13a) from the ladle slide gate (15) of the first ladle (11) that has been emptied by a robot (21) and storing the used ladle cover for repair or as waste; (h) disengaging and removing one or more drive devices (17) from the ladle slide gate (15) of the first ladle (11) by a robot (21) and storing them for further use; (i) removing the first ladle (11) that has been emptied; and (j) loading a new ladle filled with molten metal onto the first holding device of the ladle turret (30) at the loading station, wherein, similar to the second ladle (12) of step (a), the new ladle includes the ladle slide gate (15) at the sealed position and does not include the ladle cover (13a-13c). Claim 12 A method according to claim 10, wherein the opening of the first ladle is filled with a plugging material (19), and when molten metal does not flow out from the opening when the ladle sliding gate (15) of the first ladle (11) is moved to a casting station in step (b), the steps of: moving the ladle sliding gate (15) of the first ladle (11) to an unclogged position; breaking the plugging material using an unclogging tool (19r) to unclogg the opening of the first ladle; and moving the ladle sliding gate (15) of the first ladle (11) to a casting position to cast molten metal from the first ladle (11) through the unclogged opening and through the ladle cover (13a) into the tundish (1) when the plugging material begins to flow out from the collector nozzle. Claim 13 A method according to claim 10, wherein (e) the step of swapping the positions of the first and second ladles comprises: · raising the first and second ladles (11, 12) until the ladle covers (13a, 13b) of the first and second ladles are both removed from the tundish and are higher than the tundish in the vertical direction (Z); · rotating the ladle turret 180° around the vertical axis (Z) to move the first ladle (11) over the loading station and the second ladle (12) over the casting station and over the tundish (1); · lowering the first and second ladles (11, 12) to their respective loading and casting stations, wherein the ladle cover (13b) of the second ladle is inserted into the tundish (1). Claim 14 A method according to claim 10, wherein the robot also: · checks the condition of the used ladle cover (13a-13c) after removal from the empty ladle; · evaluates whether the used ladle cover can be reused after cleaning or must be discarded; and · cleans the used ladle cover with an oxygen shower to remove any residue attached to the walls of the used ladle cover.

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