Pneumatic measurement and blockage prevention method for liquid level of molten steel in continuous casting tundish

Abstract

The invention belongs to the relevant technical field of molten metal liquid level detection in the metallurgical industry, and relates to a pneumatic measurement and blockage prevention method for the liquid level of molten steel in a continuous casting tundish. Comprising a pneumatic detection control loop, a large-flow anti-blocking control loop, a high-pressure dredging loop and a self-adaptive proportional pressure module, and effective prevention and dredging of blockage of the vent plug are achieved. According to the method, the liquid level of the molten steel can be accurately measured in a normal detection mode, meanwhile, when it is detected that the blockage probability rises, an anti-blocking and dredging mode is automatically switched, and stable operation of the system is ensured. The equipment operation reliability is improved, the service life of the vent plug is prolonged, the maintenance cost is reduced, the production efficiency and the product quality are improved, and a powerful guarantee is provided for continuous casting production in the metallurgical industry.

Description

Technical Field

[0001] The present invention belongs to the technical field related to the molten metal liquid level detection in the metallurgical industry, and relates to a method for preventing blockage of pneumatic measurement of molten steel level in a continuous casting tundish. Background Art

[0002] In the metallurgical industry, the molten steel level detection technology of a continuous casting machine plays a crucial role. This technology is not only related to production efficiency and product quality, but also closely related to production safety. However, the accurate measurement of the molten steel level in the tundish has always been a technical problem, especially in a harsh working condition environment.

[0003] At present, the molten steel level detection technology in the metallurgical industry still belongs to the category of pioneer technologies in China, and the installation and application technology of the pneumatic detection porous plug supporting it is also in the process of continuous improvement. As a precision pneumatic detection element, the pneumatic detection porous plug has a small flow characteristic and extremely high requirements for airtightness at high temperature. Since the porous plug of the detection porous plug is directly in contact with the molten steel in the tundish, the working condition environment is extremely harsh, which puts extremely high requirements on the performance and durability of the porous plug.

[0004] In practical applications, the porous plug often gets blocked due to the adhesion of molten steel, which not only affects the normal operation of the pneumatic liquid level measurement system, but also increases the equipment maintenance cost and downtime. To solve this problem, some explorations and researches have been carried out in the industry, but no mature and effective anti-blocking technical solution has been formed yet.

[0005] In view of this, the present invention proposes a method for preventing blockage of pneumatic measurement of molten steel level in a continuous casting tundish. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method for preventing blockage of pneumatic measurement of molten steel level in a continuous casting tundish, and to ensure good air permeability of the porous plug under relatively harsh working conditions of the tundish through appropriate means.

[0007] To achieve the above purpose, the present invention provides the following technical solution: A method for preventing blockage of pneumatic measurement of molten steel level in a continuous casting tundish, comprising the following steps:

[0008] 1) Adopt a porous plug hardware with a specific design, which has a rated flow rate and a slit flow characteristic to prevent complete blockage of the porous plug at the hardware level;

[0009] 2) Set up a pneumatic detection system, which includes a pneumatic detection control circuit, a large-flow anti-blocking control circuit, a high-pressure blockage removal circuit, and an adaptive proportional pressure module. Among them, the pneumatic detection control circuit is used to normally detect the molten steel level, the large-flow anti-blocking control circuit is used to prevent the plugging of the porous plug, and the high-pressure blockage removal circuit is used to remove the blocked state when the detected blockage probability exceeds a preset threshold.

[0010] 3) Alternately operate the pneumatic detection circuit and the large-flow anti-blocking circuit, and monitor the blockage probability of the porous plug in real time. According to the real-time monitoring results, optimize the pressure and flow set values of the large-flow anti-blocking operation, and supply argon medium through the adaptive proportional pressure module.

[0011] 4) When the detected blockage probability of the porous plug exceeds the preset full-blockage prevention threshold, the system automatically switches to the high-pressure blockage removal circuit to work, intervenes in the blocked state of the porous plug until the detected blockage probability is reduced below the preset normal state threshold, and then the system switches back to the normal detection working mode.

[0012] Optionally, the porous plug hardware adopts a slit design to match the rated flow rate and the flow characteristics of the slit, thereby preventing the complete blockage of the porous plug.

[0013] Optionally, the pneumatic detection system further includes an instrument control box, a programmable controller, and a touch screen, which are used to control the operation of the system and display the detection and anti-blocking states.

[0014] Optionally, the full-blockage prevention threshold and the normal state threshold can be adjusted and optimized according to the actual working conditions.

[0015] Optionally, this method is applicable to the tundish liquid level detection system of a continuous casting machine in the metallurgical industry, which can effectively reduce the blockage probability of the porous plug, improve the normal operation time of the equipment, and reduce the maintenance cost.

[0016] The beneficial effects of the present invention are as follows:

[0017] (1) Significantly reduce the blockage probability of the porous plug: By adopting the porous plug hardware with a specific design and comprehensively applying the anti-blocking and blockage removal strategies of the pneumatic control system, the present invention can significantly reduce the blockage probability of the porous plug caused by molten steel adhesion and other reasons during operation, thereby ensuring the continuous and stable operation of the pneumatic liquid level measurement system.

[0018] (2) Improve the operation reliability of the equipment: Since the blockage of the porous plug is one of the main reasons for equipment failure and shutdown, the implementation of the present invention will help improve the overall operation reliability of the tundish liquid level detection system of the continuous casting machine, and reduce production interruption and equipment damage caused by blockage.

[0019] (3) Extend the service life of the breathable plug: By optimizing the design of the breathable plug and the working mode of the control system, the present invention can also extend the service life of the breathable plug, reduce the replacement frequency, and further reduce the production cost.

[0020] (4) Reduce the maintenance cost: Due to the reduction in the occurrence of clogging of the breathable plug, the implementation of the present invention will effectively reduce the costs generated by maintaining the breathable plug, including labor costs, spare parts costs, and downtime losses, etc.

[0021] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following specification. Brief Description of the Drawings

[0022] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0023] Figure 1 is a schematic diagram of the tundish liquid level detection system of the continuous casting machine of the present invention;

[0024] Figure 2 is a top view of the slit-type anti-clogging breathable plug of the present invention;

[0025] Figure 3 is Figure 2 the front view of.

[0026] Reference numerals: instrument control box 1, programmable controller and touch screen 2, pneumatic detection control loop 3, large-flow anti-clogging control loop 4, high-pressure clogging removal loop 5, adaptive proportional pressure module 6. Detailed Embodiments

[0027] The following illustrates the implementation manners of the present invention through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present invention schematically. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0028] Among them, the attached drawings are only for illustrative purposes, showing only schematic diagrams rather than actual diagrams, and should not be construed as limiting the present invention; in order to better illustrate the embodiments of the present invention, some components in the attached drawings will be omitted, enlarged or reduced, which do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the attached drawings may be omitted.

[0029] In the attached drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the attached drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the attached drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0030] Please refer to Figures 1 to 3 , which is a pneumatic measurement and anti-blocking method for molten steel level in a continuous casting tundish. In this embodiment, taking the tundish liquid level detection system of the No. 2 continuous caster in Chongqing Iron and Steel as an example, the actual application of a pneumatic measurement and anti-blocking method for molten steel level in a continuous casting tundish of the present invention is described in detail.

[0031] As shown in the figure, the system mainly includes the following components:

[0032] Instrument control box 1: Responsible for functions such as power supply, signal acquisition and transmission of the entire system.

[0033] Programmable controller and touch screen 2: As the control center of the system, it is responsible for receiving signals from the instrument control box, performing data processing and decision-making according to the preset program logic, and at the same time providing a human-machine interaction interface through the touch screen to facilitate operators to monitor and operate the system.

[0034] Pneumatic detection control loop 3: Works in the normal detection mode, detects the molten steel level in the tundish by introducing an appropriate amount of argon medium into the porous plug using the pneumatic principle.

[0035] Large-flow anti-blocking control loop 4: Works in the anti-blocking prevention mode, flushes away the molten steel impurities that may adhere to the porous plug by increasing the argon flow rate introduced into the porous plug, thereby reducing the blocking probability. The pressure and flow rate set values of this loop can be dynamically optimized according to the real-time monitoring results.

[0036] High-pressure blockage removal circuit 5: When the detected blockage probability of the breather plug exceeds the preset full blockage prevention threshold, the system automatically switches to this circuit for operation. By introducing high-pressure argon gas into the breather plug, the blocked state is strongly dredged until the detected blockage probability is reduced below the preset normal state threshold.

[0037] Adaptive proportional pressure module 6: According to the real-time monitoring results and the working requirements of the large-flow anti-blockage control circuit and the high-pressure blockage removal circuit, it automatically adjusts the pressure and flow rate set values of the argon medium to ensure the stable operation of the system and the anti-blockage effect.

[0038] In practical applications, the working process of this system is as follows:

[0039] After the system is started, it first enters the normal detection mode, and the pneumatic detection control circuit 3 starts to work. By introducing an appropriate amount of argon medium into the breather plug, the liquid level of the molten steel in the tundish is detected.

[0040] At the same time, the system real-time monitors the blockage probability of the breather plug through the instrument control box 1, the programmable controller, and the touch screen 2.

[0041] When the blockage probability reaches the preset warning value, the system automatically switches to the blockage prevention mode, and the large-flow anti-blockage control circuit 4 starts to work. By increasing the argon gas flow rate, the impurities on the breather plug are washed away.

[0042] If the blockage probability continues to rise and exceeds 80% (the full blockage prevention threshold), the system automatically switches to the high-pressure blockage removal circuit 5 for operation to strongly dredge the breather plug.

[0043] Dredge the blocked state until the detected blockage probability is less than 30% of the normal state, and then switch to the normal detection working mode.

[0044] During the whole process, the adaptive proportional pressure module 6 automatically adjusts the pressure and flow rate set values of the argon medium according to the actual needs to ensure the stable operation of the system and the best anti-blockage effect.

[0045] In this embodiment, the system can autonomously monitor the blockage state of the breather plug and automatically switch the corresponding working mode to the detection mode, the anti-blockage mode, and the blockage removal mode for relevant operations. It extends the working life of the porous plug, increases the working reliability of the system, and the robustness of the detection.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A method for preventing clogging by pneumatically measuring the molten steel level in a continuous casting tundish, characterized in that: The following steps are involved: 1) Use specially designed vent plug hardware with rated flow and gap flow characteristics to prevent complete blockage of the vent plug at the hardware level; 2) A pneumatic detection system is provided, which includes a pneumatic detection control circuit, a large flow anti-blocking control circuit and a high pressure unblocking circuit, and an adaptive proportional pressure module; wherein the pneumatic detection control circuit is used to normally detect the molten steel level, the large flow anti-blocking control circuit is used to prevent the vent plug from being blocked, and the high pressure unblocking circuit is used to clear the blockage state when it is detected that the blockage probability exceeds a preset threshold; 3) The pneumatic detection circuit and the large flow prevention circuit work alternately, and the blockage probability of the vent plug is monitored in real time; According to the real-time monitoring results, the pressure and flow set values ​​for large flow anti-blocking work are optimized, and the argon medium is set through the adaptive proportional pressure module; 4) When it is detected that the blockage probability of the vent plug exceeds the preset threshold for preventing total blockage, the system automatically switches to the high-pressure unblocking circuit to work and intervene in the blockage state of the vent plug until the blockage probability is detected to be reduced to below the preset normal state threshold, and then the system switches back to the normal detection working mode.

2. The method for pneumatically measuring the molten steel level in a continuous casting tundish to prevent blockage according to claim 1, characterized in that: The vent plug hardware adopts a slit-type design to match the rated flow and the gap flow characteristics, thereby preventing the vent plug from being completely blocked.

3. The method for pneumatically measuring the molten steel level in a continuous casting tundish to prevent blockage according to claim 1, characterized in that: The pneumatic detection system also includes an instrument control box, a programmable controller and a touch screen, which are used to control the operation of the system and display the detection and anti-blocking status.

4. The method for pneumatically measuring the molten steel level in a continuous casting tundish and preventing blockage according to claim 1, characterized in that: The total blockage prevention threshold and the normal state threshold can be adjusted and optimized according to actual working conditions.

5. The method for pneumatically measuring the molten steel level in a continuous casting tundish to prevent blockage according to claim 1, characterized in that: The method is applicable to the tundish liquid level detection system of the continuous casting machine in the metallurgical industry, which can effectively reduce the probability of blockage of the air plug, improve the normal operation time of the equipment and reduce the maintenance cost.

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