RH refining automatic jacking system and control method

Abstract

The invention belongs to the technical field of metallurgical industry, and particularly relates to an automatic jacking system for RH refining and a control method. The automatic jacking system is organically composed of an image processing module, an image acquisition module, a jacking calculation module, a control module and a jacking device. According to the automatic jacking system for RH refining, control over the automatic jacking system for RH refining is completed through the five steps that a steel ladle falls on a steel ladle car, uncovering is completed, complete equipment information is obtained, an image collecting module circularly collects a molten steel level image, an image processing module processes the image, and a control module receives an instruction of the image processing module and controls the jacking device to act. The molten steel level state fed back in real time through an image recognition algorithm serves as the input end of the closed-loop control system, the real-time position information of the jacking device serves as the output end of the closed-loop control system, the jacking speed and height are controlled in the working stage of the jacking system, it is guaranteed that a vacuum tank dip pipe is inserted into the molten steel at the optimal position, and the production efficiency is improved. And personal errors are reduced, and the RH refining production efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgical industry, and in particular relates to an RH refining automatic lifting system and a control method. Background Art

[0002] RH vacuum refining is a secondary refining process for producing high-quality steel. First, the ladle is lifted to a predetermined height by a hydraulic lifting device, and then vacuum treatment is performed. The lifting operation refers to: the lifting device drives the lifting frame to lift the ladle trolley and the ladle on the trolley through the hydraulic cylinder, and the immersion pipe of the vacuum tank is inserted into the ladle to an appropriate depth for vacuum treatment.

[0003] The main method used in traditional lifting operations is that the ladle car is lifted by a hydraulic cylinder. The specific lifting height is manually controlled and adjusted through observation. When the immersion tube of the vacuum tank enters the molten steel and is inserted to a preset depth, the lifting is completed and the vacuum pump is started. With the demand for "one-button RH refining", automatic lifting is the primary technical difficulty. The lifting time and height control still rely on manual experience and manual operation, resulting in the inability to guarantee lifting accuracy. While the production efficiency is low, it also limits the development of intelligent RH refining. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides an RH refining automatic lifting system and a control method.

[0005] To achieve the above object, the technical solution adopted by the present invention is: An RH refining automatic lifting system, the system comprising: The lifting calculation module is used to collect basic data of related equipment and calculate the target position where the immersion pipe should be inserted into the molten steel, so as to prepare for the calculation of the lifting height, i.e., the insertion depth of the immersion pipe; An image acquisition module is used to capture the liquid surface image of the RH fine process in real time and transmit the acquired image information to the image processing module; The image processing module is used to receive the image information from the image acquisition module and perform preprocessing, feature extraction and target recognition, and send control instructions; A control module, used to receive control instructions sent by the image processing module and control the lifting device to perform actions; The lifting device receives control instructions to realize the lifting and lowering of the ladle car system.

[0006] The image processing module includes OpenCV library for image preprocessing, feature extraction, and object recognition; Image processing software integrates OpenCV library to realize image recognition of molten steel surface and positioning algorithm of ladle car system, and sends control instructions to the control module.

[0007] The image acquisition module comprises High-definition, high-temperature-resistant industrial camera, used to capture the liquid level image of the RH fine process in real time; The image transmission device is used to transmit the collected image information to the image processing module.

[0008] The high-definition, high-temperature-resistant industrial camera acquires images at a shooting frequency of 35-70 ms / frame.

[0009] The control module is a PLC controller, which is used to receive control instructions sent by the image processing module and control the action of the lifting device.

[0010] It also includes a safety monitoring module; the safety monitoring module includes The sensor unit includes a limit switch and a weight sensor, which is used to monitor the position and weight parameters of the molten steel tank in real time; The emergency stop device can quickly cut off the power supply or stop the operation of the jacking device under abnormal circumstances to prevent accidents.

[0011] The lifting calculation module includes Data acquisition system, used to collect basic data of ladle, molten steel and related equipment; The lifting calculation unit is used to calculate the target position where the immersion pipe should be inserted into the molten steel based on the collected data.

[0012] A control method for an RH refining automatic lifting system, using the RH refining automatic lifting system, comprises the following steps: Step 1: The ladle is placed on the ladle car and the lid is opened; Step 2: Get complete device information; Step 3: The image acquisition module cyclically acquires the steel liquid surface image; Step 4: The image processing module processes the image; Step 5: The control module receives the instruction from the image processing module and controls the action of the lifting device; When the image processing module feeds back that the vacuum tank immersion tube has reached the surface of the molten steel, the jacking calculation module calculates the optimal depth of the immersion tube inserted into the molten steel, and the jacking control system executes the corresponding instructions, the jacking operation is completed; if the vacuum tank immersion tube has not reached the surface of the molten steel, the control module receives the image processing module instructions again to control the action of the jacking device.

[0013] The processed data obtained in step 1 include the real-time position of the ladle car during the lifting stage, the image of the molten steel surface taken in real time by a high-temperature resistant industrial camera, and the depth data of the immersion tube inserted into the molten steel.

[0014] In step 4, the image processing module processes the image by an image recognition method based on the OpenCV algorithm, feeds back the real-time position of the immersion pipe to the lifting device, and controls the automatic lifting operation through the control module.

[0015] The beneficial effects produced by the present invention are as follows: The present invention uses a phased closed-loop control method to control the ladle lifting operation in the RH refining process. In the first stage, by collecting the real-time position feedback of the ladle car during the lifting stage, the real-time image of the molten steel surface taken by the high-temperature resistant industrial camera, the depth of the immersion tube inserted into the molten steel and other data, an image recognition algorithm based on the OpenCV computer vision library is established. The molten steel surface state fed back by the image recognition algorithm in real time is used as the input end of the closed-loop control system, and the real-time position information of the jacking device is used as the output end of the closed-loop control system to realize the first stage operation control of the immersion tube entering the molten steel surface. In the second stage, by collecting the basic information of the ladle and the molten steel, the current system equipment and other data, the information is used as the input end of the closed-loop control system of this stage, the system calculates the current ladle clearance and determines the target depth of the immersion tube insertion. With the target depth of the immersion tube insertion as the output end of the closed-loop control system of this stage, the lifting speed is controlled in the second stage of the jacking system operation to ensure that the vacuum tank immersion tube is inserted into the optimal position (depth) of the molten steel, reduce human errors and improve the RH refining production efficiency.

[0016] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a flow chart of the present invention.

[0019] Figure 2 It is a system structure diagram of the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Embodiment 1: like Figure 2 As shown, an RH refining automatic lifting system, the system comprises: The lifting calculation module is used to collect basic data of related equipment and calculate the target position where the immersion pipe should be inserted into the molten steel, so as to prepare for the calculation of the lifting height, i.e., the insertion depth of the immersion pipe; An image acquisition module is used to capture the liquid surface image of the RH fine process in real time and transmit the acquired image information to the image processing module; The image processing module is used to receive the image information from the image acquisition module and perform preprocessing, feature extraction and target recognition, and send control instructions; A control module, used to receive control instructions sent by the image processing module and control the lifting device to perform actions; The lifting device receives control instructions to realize the lifting and lowering of the ladle car system.

[0022] In some embodiments, the image processing module includes OpenCV library for image preprocessing, feature extraction, and object recognition; Image processing software integrates OpenCV library to realize image recognition of molten steel surface and positioning algorithm of ladle car system, and sends control instructions to the control module.

[0023] In some embodiments, the image acquisition module includes High-definition, high-temperature-resistant industrial camera, used to capture the liquid level image of the RH fine process in real time; The image transmission device is used to transmit the collected image information to the image processing module.

[0024] The high-definition, high-temperature-resistant industrial camera acquires images at a shooting frequency of 35-70 ms / frame.

[0025] In specific applications, during the lifting process, the molten steel surface will fluctuate violently due to gas stirring, eddy currents, bubble bursting, etc. This unstable state changes rapidly, and a higher shooting frequency helps capture the real-time details of the molten steel surface fluctuations. Recommended frequency: 35-70ms / frame, which can capture the instantaneous changes of the molten steel surface during the lifting and stirring process, and facilitate monitoring the flow state and stability of the liquid surface.

[0026] The control module is a PLC controller, which is used to receive control instructions sent by the image processing module and control the action of the lifting device.

[0027] It also includes a safety monitoring module; the safety monitoring module includes A sensor unit, the sensor unit comprising a limit switch and a weight sensor, for real-time monitoring of the position and weight parameters of the molten steel tank; The emergency stop device can quickly cut off the power supply or stop the operation of the jacking device under abnormal circumstances to prevent accidents.

[0028] In actual use, the high-definition high-temperature resistant industrial camera in the image acquisition module captures the RH fine process liquid surface image in real time at a frequency of 250ms / time; the image transmission device transmits the collected image information to the image processing module. The OpenCV library in the image processing module, as the core image processing tool, provides image preprocessing, feature extraction, target recognition and other functions. The image processing software integrates the OpenCV library to realize the image recognition of the molten steel liquid surface and the positioning algorithm of the ladle car system, and sends control instructions to the control module. The PLC (programmable logic controller) in the control module receives the control instructions sent by the image processing module and controls the action of the jacking device. The jacking device, such as the hydraulic cylinder and the motor, realizes the lifting and lowering of the ladle car system according to the control instructions of the PLC. The sensors in the safety monitoring module use limit switches, weight sensors, etc. to monitor the position, weight and other parameters of the molten steel tank in real time to ensure the safety of the jacking process; the emergency stop device ensures that in abnormal circumstances, the power supply can be quickly cut off or the action of the jacking device can be stopped to prevent accidents.

[0029] The present invention uses a closed-loop control method to control the lifting of the ladle in the RH refining process. By collecting data such as real-time position feedback of the ladle car during the lifting stage, real-time image capture of the molten steel surface by a high-temperature resistant industrial camera, and the depth of the immersion tube inserted into the molten steel, an image recognition algorithm based on the OpenCV computer vision library is established to achieve the operation state control of the ladle car system during the lifting stage. The molten steel surface state fed back by the image recognition algorithm in real time is used as the input end of the closed-loop control system, and the real-time position information of the lifting device is used as the output end of the closed-loop control system. The lifting speed and height are controlled during the operation stage of the lifting system to ensure that the vacuum tank immersion tube is inserted into the optimal position of the molten steel, thereby reducing human errors and improving the RH refining production efficiency.

[0030] Embodiment 2: like Figure 1 As shown, a control method of an RH refining automatic lifting system, using the RH refining automatic lifting system, comprises the following steps: Step 1: Get complete processing data; Step 2: The ladle is placed on the ladle car and the lid is opened; Step 3: The image acquisition module cyclically acquires images of the steel liquid surface; Step 4: The image processing module processes the image; Step 5: The control module receives the instruction from the image processing module and controls the action of the lifting device; When the image processing module feeds back that the vacuum tank immersion tube has reached the surface of the molten steel, the jacking calculation module calculates the optimal target depth of the immersion tube inserted into the molten steel, and the jacking control system executes the corresponding instructions, the jacking operation is completed; if the vacuum tank immersion tube has not reached the surface of the molten steel, the control module re-receives the image processing module instructions to control the action of the jacking device.

[0031] Furthermore, the processed data acquired in step 1 includes the real-time position of the ladle car during the lifting stage, the image of the molten steel surface taken in real time by a high-temperature resistant industrial camera, and the depth data of the immersion tube inserted into the molten steel.

[0032] Furthermore, in step 4, the image processing module processes the image using an image recognition method based on the OpenCV algorithm, feeds back the real-time position of the immersion pipe to the lifting device, and controls the lifting operation automatically through the control module.

[0033] The calculation method for the optimal insertion depth of the immersion pipe in this embodiment is as follows: Known weight of molten steel , steel liquid density , ladle inner diameter 、Steel Enclosure Volume

[0034] Calculate: Liquid steel volume

[0035] Steel liquid level =

[0036] Ladle clearance

[0037] Dip tube inserted into target depth

[0038] in, It is the target depth coefficient of the immersion pipe, and its value is generally between 0.3 and 0.5.

[0039] Embodiment three: A control method for RH refining automatic lifting system In the first step, the ladle containing molten steel is placed on the ladle trolley, and the data acquisition system collects complete equipment information. After the lid-lifting device completes the ladle lid-lifting operation and reveals the entire surface of the molten steel, the robotic arm installed on the operating platform delivers a high-definition, high-temperature-resistant industrial camera to the surface of the molten steel. The industrial camera captures the image of the molten steel surface at a frequency of 250ms / time, and the image sensor transmits the results to the PC end equipped with an image recognition algorithm in real time.

[0040] In the second step, the PC-side image recognition algorithm performs online analysis on the current image. First, the acquired image is converted into a grayscale picture. The higher the grayscale value, the brighter the image. The average pixel value is calculated as the brightness, and then the image recognition result is fed back to the control system of the hydraulic jacking device.

[0041] In the third step, after receiving the feedback of the image recognition result, the lifting device controls the lifting system to automatically lift the steel, and receives the steel liquid surface image recognition result again. The image recognition algorithm and the hydraulic lifting device form a lifting closed-loop control system. When the image recognition algorithm feedbacks that the vacuum tank immersion pipe has passed through the steel liquid surface slag to reach the steel liquid, the hydraulic lifting device completes the first stage of the operation task.

[0042] In the fourth step, the basic information of the ladle, molten steel and other related equipment (such as ladle size, molten steel weight, etc.) collected by the data acquisition system is used as the second stage input, and the jacking calculation algorithm calculates the optimal position (depth) for the vacuum tank immersion pipe to be inserted into the molten steel, and the hydraulic jacking device performs the second stage jacking operation again. When the immersion pipe reaches the target position, the hydraulic jacking device stops the jacking work, and the automatic jacking operation is completed.

[0043] The present invention uses an image recognition algorithm based on the OpenCV computer vision library, which is an open source computer vision library for image processing. The specific method of use in the present invention is: first, the collected molten steel image is converted into a grayscale image using the function provided by the OpenCV algorithm, and then the pixel grayscale value, mean and standard deviation of the grayscale image are obtained. The pixel grayscale value is between 0 and 255, and the higher the pixel brightness, the higher the grayscale value; the mean represents the overall brightness of the image, and the larger the mean, the brighter the image; the standard deviation represents the contrast of the brightness change of the image, and the larger the standard deviation, the stronger the brightness change.

[0044] When the dip tube reaches the molten steel surface, the brightness is not very bright due to the slag attached to the surface of the liquid. When the dip tube penetrates the slag and contacts the molten steel, the brightness of the molten steel becomes very bright, and the first stage of lifting is completed.

[0045] In the RH refining process, since the liquid level and state of the molten steel entering each furnace are different, the vacuum tank immersion pipe needs to be manually adjusted during the process of entering the molten steel until the immersion pipe passes through the slag and reaches the appropriate position in the molten steel. Therefore, the second stage of this control system aims to calculate the optimal position of the immersion pipe inserted into the molten steel through the jacking algorithm, reduce errors and improve the RH refining production efficiency.

[0046] In the absence of conflicts, technicians in this field can combine the relevant technical features in the above examples according to actual conditions to achieve corresponding technical effects. The specific combinations are not described here one by one.

[0047] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0048] In addition, the descriptions of "first", "second", etc. in the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0049] The above are only preferred embodiments of the present invention. The present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein. Any simple modification, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An automatic lifting system for RH refining, characterized by: The system includes: The lifting calculation module is used to collect basic data of related equipment and calculate the target position where the immersion pipe should be inserted into the molten steel, so as to prepare for the calculation of the lifting height, i.e., the insertion depth of the immersion pipe; An image acquisition module is used to capture the liquid surface image of the RH fine process in real time and transmit the acquired image information to the image processing module; The image processing module is used to receive the image information from the image acquisition module and perform preprocessing, feature extraction and target recognition, and send control instructions; A control module, used to receive control instructions sent by the image processing module and control the lifting device to perform actions; The lifting device receives control instructions to realize the lifting and lowering of the ladle car system.

2. The RH refining automatic lifting system according to claim 1, characterized in that: The image processing module includes OpenCV library for image preprocessing, feature extraction, and object recognition; Image processing software integrates OpenCV library to realize image recognition of molten steel surface and positioning algorithm of ladle car system, and sends control instructions to the control module.

3. The RH refining automatic lifting system according to claim 1, characterized in that: The image acquisition module comprises High-definition, high-temperature-resistant industrial camera, used to capture the liquid level image of the RH fine process in real time; The image transmission device is used to transmit the collected image information to the image processing module.

4. The RH refining automatic lifting system according to claim 3, characterized in that: The high-definition, high-temperature-resistant industrial camera acquires images at a shooting frequency of 35-70 ms / frame.

5. The RH refining automatic lifting system according to claim 1, characterized in that: The control module is a PLC controller, which is used to receive control instructions sent by the image processing module and control the action of the lifting device.

6. The RH refining automatic lifting system according to claim 1, characterized in that: It also includes a safety monitoring module; the safety monitoring module includes The sensor unit includes a limit switch and a weight sensor, which is used to monitor the position and weight parameters of the molten steel tank in real time; The emergency stop device can quickly cut off the power supply or stop the operation of the jacking device under abnormal circumstances to prevent accidents.

7. The RH refining automatic lifting system according to claim 1, characterized in that: The lifting calculation module includes Data acquisition system, used to collect basic data of ladle, molten steel and related equipment; The lifting calculation unit is used to calculate the target position where the immersion pipe should be inserted into the molten steel based on the collected data.

8. A control method for an RH refining automatic lifting system, characterized in that: The RH refining automatic lifting system according to any one of claims 1 to 7 comprises the following steps: Step 1: The ladle is placed on the ladle car and the lid is opened; Step 2: Get complete device information; Step 3: The image acquisition module cyclically acquires the steel liquid surface image; Step 4: The image processing module processes the image; Step 5: The control module receives the instruction from the image processing module and controls the action of the lifting device; When the image processing module feeds back that the vacuum tank immersion tube has reached the surface of the molten steel, the jacking calculation module calculates the optimal depth of the immersion tube inserted into the molten steel, and the jacking control system executes the corresponding instructions, the jacking operation is completed; if the vacuum tank immersion tube has not reached the surface of the molten steel, the control module receives the image processing module instructions again to control the action of the jacking device.

9. The control method of the RH refining automatic lifting system according to claim 8, characterized in that: The processed data obtained in step 1 include the real-time position of the ladle car during the lifting stage, the image of the molten steel surface taken in real time by a high-temperature resistant industrial camera, and the depth data of the immersion tube inserted into the molten steel.

10. A control method for an RH refining automatic lifting system as claimed in claim 8 or 9, characterized in that: In step 4, the image processing module processes the image by an image recognition method based on the OpenCV algorithm, feeds back the real-time position of the immersion pipe to the lifting device, and controls the automatic lifting operation through the control module.

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