Submerged entry nozzle quick change and crystallizer slag addition robotic system and method of use

Abstract

The present application relates to the field of device for supporting, operating or replacing casting nozzle of a container for casting a melt, in particular to a submerged nozzle quick-change and crystallizer slagging robot system and a use method thereof. The submerged nozzle quick-change and crystallizer slagging robot system comprises an execution module (1), a visual positioning module (2) and a centralized control system (3), characterized in that: the execution module (1) comprises an inverted track robot (11) and an end effector (12); the visual positioning module (2) comprises at least one binocular camera (21); and the centralized control system (3) comprises a programmable logic controller (31), an industrial computer (32) and a robot control cabinet (33). The present application has high automation degree, reduces labor intensity and improves production efficiency.

Description

Technical Field

[0001] This invention relates to the field of devices for supporting, manipulating, or replacing pouring nozzles in casting molten material containers, specifically a robotic system for quick-change of immersion nozzles and slag addition to crystallizers, and its method of use. Background Technology

[0002] In slab continuous casting production, the tundish typically lasts for 15 heats, but the submerged entry nozzle only lasts for about 9 heats. This is mainly due to the erosion of the nozzle by the protective slag and the deposition of inclusions in the molten steel, which leads to nozzle blockage and affects the stability of the molten steel flow field within the mold. The submerged entry nozzle usually needs to be replaced after the 8th or 9th heat.

[0003] Currently, most water inlet replacements rely on manual operation, which presents the following problems: 1. The manual labor is physically demanding and the ambient temperature is high (approximately 800℃), posing safety hazards; 2. Differences in the skill levels of various operators can easily lead to fluctuations in the molten steel level in the crystallizer, thereby affecting product quality; 3. The existing robot-assisted slag replacement solution cannot achieve rapid nozzle replacement, has limited functionality, and lacks sufficient automation.

[0004] Therefore, there is a need for an automated system that can be completed by robots in a limited space for quick replacement of submerged nozzles and slag addition to crystallizers, in order to reduce labor intensity, improve safety and production stability. Summary of the Invention

[0005] In order to overcome the shortcomings of the existing technology and provide a replacement device that is highly adaptable to the environment, reduces labor intensity, and is safe and reliable, this invention discloses a robot system for quick-change of immersion nozzles and slag addition to crystallizers, and its usage method.

[0006] The present invention achieves its objective through the following technical solution: A robotic system for quick-change of immersion nozzles and slag addition to a crystallizer includes: an execution module, a vision positioning module, and a centralized control system. The centralized control system is connected to the execution module and the vision positioning module via signal lines. Its characteristics are: The execution module includes an inverted track robot and an end effector. The inverted track robot is installed on a retractable or fixed track. The inverted track robot is connected to a servo motor via a signal line, and the servo motor drives the inverted track robot to move along the track. The inverted track robot is connected to an end effector via a flange interface. The end effector is used to hold the immersion nozzle and the feed pipe. The visual positioning module includes at least one binocular camera, which is used to detect intermediate bag reference marks and determine real-time position deviation; The centralized control system includes a programmable logic controller (PLC), an industrial computer, and a robot control cabinet. The robot control cabinet is connected to the PLC and the industrial computer via signal lines. The PLC is connected to the end effector via signal lines, and the industrial computer is connected to a binocular camera via signal lines. The centralized control system is used to coordinate communication between the execution module, the vision positioning module, and the continuous casting main control system.

[0007] The aforementioned immersion-type quick-change water inlet and slag-adding robot system for crystallizers is characterized by: If a fixed track would obstruct the movement of the intermediate car or the derrick car, a telescopic track should be selected. The inverted track robot can be a six-axis or four-axis industrial robot. The inverted track robot is controlled by a standard control cabinet and programming language, or by a custom coordinate system. The end effector includes interchangeable gripping fixtures, cylinders, and directional valves. The gripping fixtures are connected to the cylinders via an air supply pipe that connects the directional valves in series. The gripping fixtures are equipped with a heat insulation layer. The gripping fixtures are driven by the cylinders and controlled to open and close by the directional valves. The heat insulation layer of the gripping fixtures is adapted to metallurgical environments above ℃.

[0008] The aforementioned immersion-type quick-change water inlet and crystallizer slag addition robot system is characterized in that: the vision positioning module generates Euler angle coordinate data (X,Y,Z,a,b,c) through a binocular camera and inputs it into the centralized control system, and the centralized control system corrects the trajectory of the inverted track robot in real time through a homogeneous transformation matrix.

[0009] The robot system for quick-change of immersion nozzle and slag addition to crystallizer is characterized in that: the centralized control system also includes a human-machine interface and an industrial Ethernet; the robot control cabinet is connected to the programmable logic controller, the industrial computer and the human-machine interface respectively through the industrial Ethernet; the programmable logic controller is connected to the end effector through the industrial Ethernet; and the industrial computer is connected to the binocular camera through the industrial Ethernet. The centralized control system uses industrial Ethernet communication to synchronize the movements of the inverted track robot with the continuous casting process.

[0010] The robot system for quick-change of immersion nozzle and slag addition to crystallizer is characterized in that it further includes a base coordinate establishment module, which calculates the reference coordinate system using the three-point method and stores it in a FRAME data structure. The visual positioning module restores the three-dimensional coordinates of the sprue quick-change target through polar geometry calibration, with a positioning accuracy of no less than 1mm.

[0011] The aforementioned immersion-type quick-change nozzle and crystallizer slag feeding robot system is characterized by: further including auxiliary devices, which are used for temporarily placing nozzle components in a nozzle storage rack, for directional slag feeding pipes, and an electrical cabinet installed on site.

[0012] The method of using the aforementioned immersion-type quick-change nozzle and crystallizer slag-adding robotic system is characterized by the following steps being implemented sequentially: S1. Drive the inverted track robot to move along the track to the preset working position; S2. The inverted track robot uses a flange interface to clamp the preheating water inlet or the feeding pipe with the end effector; S3. The visual positioning module acquires real-time images of the intermediate package reference marker using a binocular camera and calculates the positional deviation; S4. The centralized control system calculates and corrects the working trajectory of the inverted track robot through homogeneous transformation matrix calculation; S5. Under the coordination of communication between the centralized control system and the continuous casting main control system, the nozzle replacement and slag addition operations are completed.

[0013] This invention provides a robotic device mounted on an inverted track. The robot can be a multi-axis servo-driven robotic arm, equipped with replaceable flange tools and a gripping device at its end, for stable operation under high-temperature conditions. The gripping device can reliably clamp and transport the feed pipe and preheating water inlet, ensuring safety and stability within a confined space.

[0014] On the other hand, the present invention incorporates a visual recognition system. This system may include a binocular camera or a structured light sensor for locating the quick-change nozzle mechanism and determining precise installation coordinates. The visual data is processed by an industrial computer and transmitted to the robot control system via an industrial Ethernet protocol, enabling the robot to dynamically correct its trajectory and avoid obstacles in confined spaces, achieving high-precision operation.

[0015] Furthermore, this invention provides a centralized control system, including a programmable logic controller (PLC), input / output modules, and a robot control cabinet. This control system can coordinate the operation of the robot, vision module, human-machine interface, and peripheral devices, and maintain communication interlock with the continuous casting main control system, thereby ensuring the continuity and safety of the process.

[0016] By combining robotic operation, vision-based precise positioning, and automated control, this invention achieves the dual functions of adding protective slag and quick-change of submerged nozzles. It can complete complex process actions under unmanned conditions, thereby significantly reducing the labor intensity of workers, reducing the risk of high-temperature operations, improving the stability of the continuous casting process, and extending the number of consecutive furnaces cast in the tundish, ultimately reducing the overall production cost. Attached Figure Description

[0017] Figure 1 This is a flowchart of the quick-change process for the sprue nozzle of the present invention. Figure 2 This is a flowchart of the slag addition process of the present invention. Figure 3 This is a schematic diagram of the robot trajectory and motion process in this invention. Figure 4 This is a schematic diagram of the homogeneous transformation matrix in this invention. Figure 5 This is a schematic diagram of the binocular vision geometry principle in this invention. Figure 6 This is a diagram showing the components of the binocular vision positioning system in this invention. Figure 7 This is the network topology diagram of the control system in this invention. Figure 8 This is a schematic diagram of the inverted robot in this invention. Figure 9 This is a schematic diagram of the inverted robot auxiliary device structure in this invention. Figure 10 This is a schematic diagram of the base coordinate positioning in this invention. Detailed Implementation

[0018] The present invention will be further illustrated below through specific embodiments. Example

[0019] A robotic system for quick-change of immersion nozzles and slag addition to a crystallizer includes: an execution module 1, a vision positioning module 2, and a centralized control system 3. The centralized control system 3 is connected to the execution module 1 and the vision positioning module 2 via signal lines, such as... Figures 1-9 As shown, the specific structure is: Execution module 1 includes an inverted track robot 11 and an end effector 12. The inverted track robot 11 is installed on a retractable or fixed track 111. The inverted track robot 11 is connected to a servo motor 112 via a signal line. The servo motor 112 drives the inverted track robot 11 to move along the track 111. The inverted track robot 11 is connected to the end effector 12 via a flange interface. The end effector 12 is used to clamp the immersion nozzle and the feeding pipe. The visual positioning module 2 includes at least one binocular camera 21, which is used to detect intermediate bag reference marks and determine real-time position deviation. The centralized control system 3 includes a programmable logic controller 31, an industrial computer 32, and a robot control cabinet 33. The robot control cabinet 33 is connected to the programmable logic controller 31 and the industrial computer 32 via signal lines. The programmable logic controller 31 is connected to the end effector 12 via signal lines, and the industrial computer 32 is connected to the binocular camera 21 via signal lines. The centralized control system 3 is used to coordinate the communication between the execution module 1, the vision positioning module 2, and the continuous casting main control system.

[0020] In this embodiment: Track 111 can be fixed. If a fixed track would obstruct the movement of the intermediate car or the derrick car, a telescopic track should be used. The inverted track robot 11 is a six-axis or four-axis industrial robot. The inverted track robot 11 is controlled by a standard control cabinet and programming language, or by a custom coordinate system. The end effector 12 includes an interchangeable gripping clamp 121, a cylinder 122, and a reversing valve 123. The gripping clamp 121 is connected to the cylinder 122 through an air supply pipe connected in series with the reversing valve 123. The gripping clamp 121 is provided with a heat insulation layer. The gripping clamp 121 is driven by the cylinder 122 and controlled to open and close by the reversing valve 123. The heat insulation layer of the gripping clamp 121 is adapted to metallurgical environments above 800°C.

[0021] In this embodiment: the visual positioning module 2 generates Euler angle coordinate data (X,Y,Z,a,b,c) through the binocular camera 21 and inputs it into the centralized control system 3. The centralized control system 3 corrects the trajectory of the inverted track robot 11 in real time through the homogeneous transformation matrix.

[0022] In this embodiment: the centralized control system 3 also includes a human-machine interface 34 and an industrial Ethernet 35. The robot control cabinet 33 is connected to the programmable logic controller 31, the industrial computer 32 and the human-machine interface 34 respectively through the industrial Ethernet 35. The programmable logic controller 31 is connected to the end effector 12 through the industrial Ethernet 35. The industrial computer 32 is connected to the binocular camera 21 through the industrial Ethernet 35. The centralized control system 3 communicates via industrial Ethernet 35 to synchronize the movements of the inverted track robot 11 with the continuous casting process.

[0023] This embodiment also includes a base coordinate establishment module 4, which calculates the reference coordinate system using the three-point method and stores it in a FRAME data structure; The visual positioning module 2 restores the three-dimensional coordinates of the sprue quick-change target through polar geometry calibration, with a positioning accuracy of not less than 1mm.

[0024] This embodiment also includes an auxiliary device 5, which is used to temporarily place the sprue assembly in a sprue storage rack, a feeding pipe for directional feeding of slag, and an electrical cabinet installed on site.

[0025] Brief description of the features of each component: 1. Inverted Track Robot: The inverted track robot 11 is installed on an inverted track 111, which can be either fixed or telescopic. When track 111 does not affect the movement of the derrick car or tundish car, the fixed type is preferred because the structure is simpler and more reliable. If a fixed track 111 would obstruct movement, a telescopic track would be used to ensure that the operation of the inverted track robot 11 and the passage of vehicles do not interfere with each other.

[0026] The inverted track robot 11 moves along the track 111 via a servo drive system and completes the slag addition and quick-change of water inlet operations via the end effector 12.

[0027] 2. Configuration of the inverted track robot: The inverted track robot 11 can be configured with either six or four axes: The six-axis robot comes with a standard control cabinet and programming language, making it suitable for complex operations; The four-axis robot is controlled by a self-developed underlying coordinate system and can perform repetitive trajectory actions such as quick sprue replacement.

[0028] The implementation of trajectory movements is based on the definition of several coordinate points in space. Through point-by-point teaching or offline planning, a complete operation path is formed to ensure the robot's repeatability accuracy.

[0029] 3. Flange interface and end effector: The end effector 12 is connected to the inverted track robot 11 via a flange interface. A gripper 121 is mounted on one end of the end effector 12 as a tool for adding slag or quickly changing water inlets. The end effector 12 is driven by a cylinder 122 and its opening and closing actions are controlled by a reversing valve 123. To adapt to the high-temperature metallurgical environment, both the gripper 121 and the end effector 12 are equipped with heat insulation layers to ensure long-term stable operation.

[0030] 4. Visual positioning module: Since the installation locations of different intermediate packages vary, this system introduces a visual positioning module 2 for visual positioning.

[0031] The binocular camera 21 can be mounted on the end of the inverted track robot 11 or on a fixed platform. The visual positioning module 2 captures images of key marker points on the intermediate package, calculates the deviation between the actual position and the standard reference, and thus achieves real-time correction of the working points of the inverted track robot 11, with a positioning accuracy better than 1mm. The data type is Euler angle notation: (X,Y,Z,a,b,c), where X,Y,Z are coordinate values, and a,b,c are rotation angles. The coordinate system transformation process is as follows: first, translate the origin to X,Y,Z; then rotate around the Z-axis by angle a; then rotate around the Y-axis by angle b; and finally rotate around the X-axis by angle c.

[0032] In three dimensions, homogeneous transformation matrices are generally used, such as... Figure 4 As shown, the position and orientation changes between coordinate systems are described. It is equivalent to the robot's FRAME data type (Euler angle representation). In image processing software, the homogeneous transformation matrix is ​​mainly used for description and calculation.

[0033] The homogeneous transformation matrix is ​​used to determine the position of a fixed point P in a moving coordinate system {A} within a fixed reference coordinate system {B}. Given coordinate systems {A}, {B}, and {C}, and knowing the description of {B} relative to {A}, and the description of {C} relative to {B}, then the description of {C} relative to {A}.

[0034] 5. Robot base coordinate establishment: The base coordinate system is established using the three-point method. By selecting three non-collinear points on site, the inverted track robot 11 can calculate the base coordinate system and save it as a FRAME data structure with the format X, Y, Z, a, b, c.

[0035] The coordinate transformation relationship of the inverted track robot 11 can be derived as follows: The base coordinate system of the inverted track robot 11 is a coordinate system created at a certain position around the inverted track robot 11 based on the world coordinate system. Its purpose is to ensure that the movement and programmed position of the inverted track robot 11 are referenced to this coordinate system. When the position and attitude of this reference point deviate in the world coordinate system, the inverted track robot 11 can find the target object simply by correcting the base coordinate system. Generally, the edges of workpiece supports and drawers, pallets, or the outer edge of the machine can all serve as reasonable reference points for the base coordinate system.

[0036] The inverted track robot 11 can establish its base coordinate system using the three-point method (origin, square point on the X-axis, and positive Y-value point on the XY plane), such as... Figure 10 As shown, the data is stored using a FRAME data structure. When the base coordinates are moved, as long as the relationship between the old and new base coordinates is known, the new base coordinate system can be obtained through transformation spatial geometry calculations.

[0037] 6. Binocular Vision and Polar Geometry The two optical centers of the binocular camera 21 are C and C′, respectively. The projections of the target point P onto the imaging planes of the two cameras are p and p′. The line connecting the two, CC′, and point P define the polar plane π, which intersects at the image plane to form epipolar lines l and l′, with the intersection points being poles e and e′.

[0038] The three-dimensional coordinates of the target point can be recovered through polar geometry constraints and camera calibration.

[0039] The triangulation formula for binocular vision is: For a binocular vision system, there are two cameras, with their optical centers defined as C and C'. In three-dimensional space, there exists a scene point X. The plane formed by this point and the optical centers of the two cameras is the epipolar plane π. Each camera has an image plane, Image1 and Image2. CX intersects Image1 at point x, and C'X intersects Image2 at point x'. The line CC' intersects the two image planes at points e and e', these two points are called poles, and CC' is called the baseline. The epipolar plane intersects the image planes at two epipolar lines l and l'. These two epipolar lines are corresponding, and x, e, x', and e' lie on l and l', respectively. Figure 5 As shown.

[0040] As the points in the 3D scene move, the epipolar planes will rotate around the baseline. These epipolar planes together form an epipolar bundle, which intersects the image plane to form an epipolar family, which intersects at two poles, e and e'.

[0041] By calibrating the parameters of the binocular camera 21, the position and attitude relationship (i.e., homogeneous transformation matrix) of C relative to C' can be determined. If the positions of the projection point x on image plane Image1 and the projection point x' on image plane Image2 are known, the homogeneous transformation matrix can be calculated. By determining the positions of three points on the calibration plate, the homogeneous transformation matrix of the optical origin coordinate system {C} of the binocular camera 21 relative to the target plate coordinate system {P} can be obtained using the three-point method. The inverse of the matrix is ​​then obtained. The values ​​of C and P are calculated during calibration and measurement respectively. Matrix multiplication (equivalent to the KUKA operator ":") yields the homogeneous transformation matrix of the current target plate coordinate system {} relative to the coordinate system {} during target plate calibration, which is then converted to FRAME format, i.e., FRAME_Change.

[0042] 7. Control System The control system includes: Siemens PLC (1500 series), ET200, IO modules; Industrial routers, power modules, and touch screens; Two portable programmers; KUKAKRC4 control system.

[0043] 7.1 Control Flow The operating process of the control system is as follows: Figure 7 As shown. The system first enters the Home (500) initial state, and then proceeds with various operation steps: a. Pick-up and drop-down process: From the Home state, the control system can enter MagGet (506) to acquire the workpiece or component; after completion, it enters MagPut (507) to place the component in the specified position; during this process, the system can choose to end as needed and enter Finish (599) state.

[0044] b. Heating process: From the Home state or the pick-up / place-down step, the system can enter HeaterGet (510); then enter HeaterPre (520) for pre-processing, and then enter HeaterPut (511) to complete the placement; then enter TurningOut (530) to perform the rotation operation.

[0045] c. Rotation and positioning process: In the TurningOut (530) state, the workpiece is rotated to a predetermined angle; then it enters CamLocation (532) to determine the precise position.

[0046] d. Installation and disassembly process: After positioning is completed, the system can enter AttachPre (536) and then Attach (537) to complete the installation operation; or enter DetachPre (550) and then Detach (552) to complete the disassembly operation; after the above installation or disassembly is completed, the process returns to TurningIn (531).

[0047] e. Recycling and End: From TurningIn (531), the system can choose according to the task requirements: return to Home (500) to prepare for the next cycle; enter Discard (560) to discard unnecessary workpieces; or directly enter Finish (599) to end the entire process.

[0048] Thus, the control system, through state switching, realizes a complete operational logic from workpiece acquisition, preprocessing, rotational positioning, installation or disassembly, to final completion. This process ensures controllable sequence and clear logic between each process, and supports flexible selection under different working conditions. Furthermore, the system uniformly coordinates the inverted track robot 11, the turntable, and the vision module, achieving real-time communication and task scheduling.

[0049] 8. Auxiliary equipment The supporting auxiliary devices include: Sprue storage rack, used for temporary placement of sprue components; Feed pipe, used for targeted feeding of slag materials; Electrical cabinets and signal cabinets are installed on-site or in the electrical room, respectively.

Claims

1. A robotic system for quick-change of submersible nozzles and slag addition to a crystallizer, comprising: The system consists of an execution module (1), a vision positioning module (2), and a centralized control system (3). The centralized control system (3) is connected to the execution module (1) and the vision positioning module (2) via signal lines. Its characteristics are: The execution module (1) includes an inverted track robot (11) and an end effector (12). The inverted track robot (11) is installed on a retractable or fixed track (111). The inverted track robot (11) is connected to a servo motor (112) via a signal line. The servo motor (112) drives the inverted track robot (11) to move along the track (111). The inverted track robot (11) is connected to the end effector (12) via a flange interface. The end effector (12) is used to hold the immersion nozzle and the feed pipe. The visual positioning module (2) includes at least one binocular camera (21), which is used to detect intermediate bag reference marks and determine real-time position deviation; The centralized control system (3) includes a programmable logic controller (31), an industrial computer (32), and a robot control cabinet (33). The robot control cabinet (33) is connected to the programmable logic controller (31) and the industrial computer (32) via signal lines. The programmable logic controller (31) is connected to the end effector (12) via signal lines. The industrial computer (32) is connected to the binocular camera (21) via signal lines.

2. The immersion-type quick-change nozzle and crystallizer slag-adding robotic system as described in claim 1, characterized in that: The track (111) can be fixed or telescopic; The inverted track robot (11) is a six-axis industrial robot or a four-axis industrial robot. The end effector (12) includes interchangeable gripping clamps (121), cylinders (122) and directional valves (123). The gripping clamps (121) are connected to the cylinders (122) via an air supply pipe connected in series with the directional valves (123). The gripping clamps (121) are provided with a heat insulation layer.

3. The immersion-type quick-change nozzle and crystallizer slag-adding robotic system as described in claim 2, characterized in that: The visual positioning module (2) generates Euler angle coordinate data (X,Y,Z,a,b,c) through the binocular camera (21) and inputs it into the centralized control system (3). The centralized control system (3) corrects the trajectory of the inverted track robot (11) in real time through the homogeneous transformation matrix.

4. The immersion-type quick-change nozzle and crystallizer slag-adding robotic system as described in claim 3, characterized in that: The centralized control system (3) also includes a human-machine interface (34) and an industrial Ethernet (35). The robot control cabinet (33) is connected to the programmable logic controller (31), the industrial computer (32) and the human-machine interface (34) via the industrial Ethernet (35). The programmable logic controller (31) is connected to the end effector (12) via the industrial Ethernet (35), and the industrial computer (32) is connected to the binocular camera (21) via the industrial Ethernet (35).

5. The immersion-type quick-change nozzle and slag-adding robot system for crystallizers as described in claim 4, characterized in that: It also includes a base coordinate establishment module (4), which calculates the reference coordinate system using the three-point method and stores it in a FRAME data structure; The visual positioning module (2) restores the three-dimensional coordinates of the water inlet quick-change target through polar geometry calibration, with a positioning accuracy of not less than 1mm.

6. The immersion-type quick-change nozzle and slag-adding robot system for crystallizers as described in claim 5, characterized in that: It also includes auxiliary devices (5), which are used to temporarily place the sprue assembly in a sprue storage rack, a feeding pipe for directional feeding of slag, and an electrical cabinet installed on site.

7. The method of using the submersible nozzle quick-change and crystallizer slag-adding robotic system as described in any one of claims 1 to 6, characterized in that: Follow these steps in sequence: S1. Drive the inverted track robot (11) to move along the track (111) to the preset working position; S2. The inverted track robot (11) uses a flange interface to allow the end effector (12) to clamp the preheating water inlet or the feeding pipe; S3. The visual positioning module (2) acquires real-time images of the intermediate package reference mark through a binocular camera (21) and calculates the position deviation; S4. The centralized control system (3) calculates and corrects the working trajectory of the inverted track robot (11) through homogeneous transformation matrix; S5. Under the coordination of communication between the centralized control system (3) and the continuous casting main control system, the nozzle replacement and slag addition operations are completed.

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