Method for removing cold steel outside RH vacuum tank line

Abstract

The invention relates to the technical field of cold steel removal before replacement and masonry of an RH vacuum tank in the ferrous metallurgy industry, and discloses a method for removing cold steel outside an RH vacuum tank line. The method comprises the steps that S1, an RH vacuum tank is moved to a non-production area, and the position of cold steel and the pre-estimated amount of the cold steel are determined; s2, the slag receiving device runs according to a remote instruction to reach a cold steel position to receive molten cold steel; top lance parameters are remotely set according to the pre-estimated quantity of the cold steel, and the top lance works according to the remote parameters to heat and melt the cold steel; when the cold steel is melted, the cold steel removal condition is analyzed through visual monitoring, and a feedback result is used for a central remote adjustment strategy. According to the method, the RH vacuum tank off-line cold steel removal process is adopted, the effect is remarkable, seamless butt joint vacuum tank replacement is achieved, and improvement of the overall efficiency of the RH furnace is promoted; the cold steel removal quality is guaranteed through top lance temperature control, refractory treatment is facilitated through nondestructive testing, dust is effectively controlled through dust removal facilities, slag recovery and emission reduction are achieved, and stable implementation of the process is supported.

Description

Technical Field

[0001] The invention relates to the technical field of cold steel removal before replacement and masonry of an RH vacuum tank in the iron and steel metallurgical industry, and in particular to a method for removing cold steel outside an RH vacuum tank line. Background Art

[0002] In modern steel production, the RH furnace vacuum tank is of great significance to molten steel refining and can improve the quality of molten steel. However, during the molten steel refining process, the refractory materials inside the vacuum tank will be eroded by the molten steel, baked at high temperature and chemically eroded by the components of the molten steel. The iron oxide and other components in the molten steel will react chemically with the refractory materials. Over time, the refractory materials will peel off, become thinner, and crack. Once the refractory materials are severely damaged, they cannot effectively insulate and protect the outer shell of the vacuum tank, and will also affect the quality of the molten steel, so they need to be replaced. Before replacing the tank body, the cold steel in the tank body needs to be removed to ensure the safety of the masonry personnel and equipment to prevent the cold steel from falling off and injuring people, and the residual cold steel may fall off and fall into the molten steel after the new vacuum tank is put into use. The impurities in the cold steel will increase the inclusions in the molten steel and reduce the purity of the molten steel.

[0003] At present, when replacing the vacuum tank, the tank body is first baked and heated to 1300℃, and then a Laval nozzle oxygen gun is used to accelerate from subsonic to supersonic speed, thereby generating a high-speed jet (2000Nm 3 / h) Forced oxygen blowing is performed on the cold steel of the vacuum tank wall to remove the cold steel. A violent oxidation reaction occurs between the high-flow pure oxygen and the cold steel. The iron element in the cold steel is oxidized, and other impurity elements (such as manganese, silicon, etc.) also undergo oxidation reactions when blowing oxygen, producing a large amount of metal oxide smoke. These smoke will not only affect visibility in the workplace, but also cause harm to the respiratory tract of operators. At the same time, the emission of smoke does not meet environmental protection requirements and causes environmental pollution. In addition, the existing online method for removing cold steel in vacuum tanks has a cycle of up to 4-5 hours, which interrupts production continuity, restricts the improvement of production efficiency, and increases production costs.

[0004] Chinese patent CN106011386B discloses a control method for RH top gun cold steel, and its technical solution is mainly to solve the technical problems in the prior art that the top gun position, flow rate and duration control are fuzzy, resulting in unstable cold steel efficiency and easy to cause excessive damage to refining equipment. The shortcomings of this technical solution are: it is necessary to carry out cold steel processing online, occupying production equipment, being too cumbersome in actual operation, the cold steel cycle is long, and the conditions are restrictive, which is not conducive to efficient production and restricts the release of production capacity. This situation requires personnel to make judgments and operations, and this patent does not mention the cleaning effect of cold steel in the vacuum tank. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems in the prior art that the online process for removing cold steel in an RH vacuum tank is time-consuming, has low production efficiency, high production cost and serious environmental pollution. A method for removing cold steel outside the RH vacuum tank line is provided. The method adopts the process for removing cold steel outside the RH vacuum tank line, and the implementation effect is significant, realizing seamless vacuum tank replacement and promoting the improvement of the overall efficiency of the RH furnace; top gun temperature control ensures the quality of cold steel removal, non-destructive testing is conducive to refractory processing, dust removal facilities effectively control smoke and dust, slag recovery reduces emissions, and supports stable implementation of the process.

[0006] In order to achieve the above object, the present invention provides a method for removing cold steel outside the RH vacuum tank line, the method comprising the following steps:

[0007] S1. Move the RH vacuum tank to a non-production area, inspect the cold steel, and determine the cold steel location and estimated cold steel quantity;

[0008] S2. The slag receiving device runs according to remote instructions to reach the cold steel position to receive the molten cold steel; in the fully automatic mode, the top gun parameters are set remotely according to the estimated amount of cold steel, and the top gun works according to the remote parameters to heat and melt the cold steel through coal oxygen baking operation; when the cold steel is melted, the cold steel removal situation is analyzed through visual monitoring, and the feedback results are used for the central remote adjustment strategy.

[0009] Preferably, in step S1, the transfer equipment is directed by an automated control system to move the RH vacuum tank to a non-production area.

[0010] Preferably, in step S1, the process of detecting the cold steel includes: automatically detecting the cold steel using ultrasonic detection equipment.

[0011] Preferably, in step S2, the top gun parameters include a set flow ratio of coal gas to oxygen.

[0012] Preferably, the flow ratio of coal gas to oxygen is set to 1:1-2.

[0013] Preferably, in step S2, the process of heating and melting the cold steel through the coal-oxygen baking operation includes: according to the set flow ratio of coal gas to oxygen, first opening the gas valve, then opening the oxygen valve, performing the ignition operation, igniting the coal-oxygen mixed gas sprayed from the top gun, and baking the cold steel in the RH vacuum tank.

[0014] Preferably, in step S2, the heating temperature for heating and melting the cold steel is 1250-1350°C.

[0015] Preferably, the method further comprises: in step S3, when the cold steel is melted, automatically operating dust removal facilities to process smoke.

[0016] Preferably, in step S2, the process of analyzing the cold steel removal situation through visual monitoring when the cold steel is melted includes: installing a high-definition camera in the RH vacuum tank to collect images and transmit them to a remote control center, and an image processing system analyzes the cold steel removal situation.

[0017] Preferably, the method further comprises: after the cold steel is removed, building refractory materials outside the RH vacuum tank body.

[0018] Preferably, non-destructive testing technology is used to automatically test the RH vacuum tank refractory materials, and the results are transmitted to the remote control center to provide a basis for the refractory materials that need to be removed and replaced before masonry.

[0019] Compared with the prior art, the present invention has at least the following beneficial effects:

[0020] (1) High-efficiency off-line slag removal and production efficiency transformation

[0021] The online slagging of RH furnace restricts the continuity of production. It takes 4-5 hours to do the online slagging, which can easily affect the production schedule and the fulfillment of planned varieties. The technical solution provided by the present invention realizes the innovation of off-line slagging, and the cold steel processing time is significantly shortened to 2-2.5 hours. The significantly shortened tank changing operation time will not cause long-term stagnation, thereby increasing the daily output of the production line, reducing energy consumption, and reducing equipment maintenance costs. At the same time, it solves the problem of affecting the production schedule and the fulfillment of planned varieties due to the replacement of vacuum tank online slagging, ensuring the continuity and stability of production.

[0022] (2) Refractory protection and cost optimization

[0023] Avoid the erosion of refractory materials by traditional forced oxygen blowing, and extend the service life of refractory materials by 20%. Off-line slag removal adopts the automatic slag removal mode of coal oxygen baking, and the top gun slag removal can move up and down in the vacuum tank, which is conducive to cleaning the residual steel and slag, reducing the adverse effects on refractory materials, and reducing the replacement frequency and cost.

[0024] (3) Intelligent precision control and assurance

[0025] Intelligent control: The system generates solutions based on vacuum tank parameters and cold steel estimation, automatically adjusts equipment parameters and makes adaptive adjustments based on sensor feedback to improve accuracy and stability;

[0026] Technology combination: The central control system accurately controls the coal-oxygen baking parameters, effectively softens and decomposes cold steel, and reduces thermal shock to refractory materials;

[0027] Equipment and monitoring: The special cold steel removal equipment is multifunctional and self-adjustable, and the visual monitoring system assists decision-making, improves the accuracy of slag removal operation and achieves efficient removal of cold steel in the vacuum tank (about 1 ton / minute).

[0028] (4) Environmental protection and resource recycling benefits

[0029] Off-line rapid replacement makes the entire slagging process more efficient, reduces exhaust gas and dust emissions by 95%, reduces environmental pollution pressure, helps companies meet environmental protection requirements and reduce environmental risks. The off-line slagging process can recycle waste heat and valuable metals, achieving a win-win situation for environmental protection and economy. DETAILED DESCRIPTION

[0030] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0031] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0032] The process path for removing cold steel off-line in the RH vacuum tank provided by the present invention is: adjusting the RH vacuum tank away from the production area → removing cold steel by slag off-line → laying refractory materials.

[0033] Specifically, the method for removing cold steel outside the RH vacuum tank line includes the following steps:

[0034] S1. Move the RH vacuum tank to a non-production area, inspect the cold steel, and determine the cold steel location and estimated cold steel quantity;

[0035] S2. The slag receiving device runs according to remote instructions to reach the cold steel position to receive the molten cold steel; in the fully automatic mode, the top gun parameters are set remotely according to the estimated amount of cold steel, and the top gun works according to the remote parameters to heat and melt the cold steel through coal oxygen baking operation; when the cold steel is melted, the cold steel removal situation is analyzed through visual monitoring, and the feedback results are used for the central remote adjustment strategy.

[0036] In one embodiment, when the RH vacuum tank needs to be replaced, the automated control system directs the transfer equipment to move the RH vacuum tank to a non-production area, where the cold steel is removed and does not occupy the production area, thereby improving production efficiency. The process is operated by a remote control center. The transfer equipment may be a transfer vehicle, and the transfer speed may be 1-2 m / s.

[0037] In one embodiment, when the RH vacuum tank reaches the non-production area, an ultrasonic detection device is used to automatically detect the cold steel, determine the cold steel position and the estimated cold steel amount, and transmit the result to the remote control center. The accuracy of the ultrasonic detection device is ±5 mm.

[0038] In the present invention, preparations need to be made before melting the cold steel. On the one hand, the slag receiving device needs to be operated according to remote instructions to reach the cold steel position. The slag receiving device is a ladle car with a slag receiving pot. The slag receiving pot is placed under the RH vacuum tank to receive the molten cold steel and slag. The slag receiving pot is lifted to a suitable position according to the lifting method during the treatment of molten steel to ensure that the immersion depth meets the requirements, usually greater than 400mm. The slag receiving pot is automatically replaced when it is full, and the cold steel slag in the slag receiving pot can be subsequently processed to achieve environmentally friendly utilization and recycle cold steel resources. On the second hand, it is necessary to check the top gun equipment to ensure that it can work normally, including whether the gun body is damaged and whether the nozzle is blocked. At the same time, check the oxygen pipeline and gas pipeline to ensure that the valve switch is flexible and there is no leakage. On the third hand, turn on relevant detection instruments, such as oxygen concentration test instruments, to monitor the oxygen content in the working environment in real time.

[0039] In the present invention, the cold steel removal process is started by automated operation. In the fully automatic mode, the remote control center remotely sets the top gun parameters according to the estimated amount of cold steel without manual operation, and then the top gun works according to the remote parameters, wherein the top gun parameters include the set flow ratio of coal gas to oxygen. In one embodiment, the set flow ratio of coal gas to oxygen can be 1:1 to 2, preferably 1:1.4. Among them, in the RH vacuum tank, the relationship between the estimated amount of cold steel and the coal gas flow rate will be affected by many factors, and needs to be continuously optimized and adjusted according to specific production data.

[0040] In the present invention, the process of heating and melting cold steel by coal-oxygen baking operation includes: according to the set flow ratio of coal gas to oxygen, first open the coal gas valve, then open the oxygen valve, perform ignition operation, ignite the coal-oxygen mixed gas sprayed from the top gun, and bake the cold steel in the RH vacuum tank. The heating temperature of heating and melting cold steel is controlled at about 1300°C, specifically, 1250-1350°C; the heating temperature is monitored and fed back by a temperature sensor (accuracy ±5°C), and the remote control system adjusts the heating power to prevent overheating.

[0041] In a more specific embodiment, the process of heating and melting cold steel through coal-oxygen baking operation includes: (1) according to the set ratio of coal gas to oxygen, for example, the ratio of coal gas to oxygen is about 1:1.4, first open the gas valve, then open the oxygen valve, perform ignition operation, ignite the coal-oxygen mixed gas sprayed from the top gun, and bake the cold steel in the RH vacuum tank; (2) according to the position and distribution of the cold steel in the vacuum tank, set the top gun position according to the principle of "high first and low later". At the beginning, the top gun is placed at a higher position and baked with a larger gas and oxygen flow rate to allow the cold steel to be initially heated and softened; (3) As the baking progresses, the gun position is gradually lowered, and the gas and oxygen flow rates are adjusted in time according to the melting condition of the cold steel, so that the heat generated by the combustion of coal and oxygen can be effectively transferred to the cold steel, accelerating the melting of the cold steel; (4) When liquid slag flows out of the insertion tube, the top gun position is further adjusted. The adjustment range each time can be between 100-500mm. It can be adjusted 2-5 times during the oxygen blowing period, and each adjustment is maintained for 5-20 minutes to ensure that the cold steel can be fully melted and fall off the tank wall.

[0042] In the present invention, the process of heating and melting the cold steel also includes the end operation. Specifically, the end operation includes the following steps: (1) when the cold steel is basically melted and removed, first close the gas valve, then close the oxygen valve, and stop the coal oxygen baking operation; (2) open the nitrogen protective gas of the top gun, and the nitrogen flow rate is generally 100-200m 3 / h, purge for 5-20min to reduce the oxygen concentration in the vacuum chamber and prevent the residual oxygen from reacting with the equipment or the surrounding environment. (3) After the oxygen concentration in the vacuum chamber is reduced, lift the top gun to the standby position, and finally remove the slag tank, clean and inspect the equipment and the work site to prepare for the next operation.

[0043] In the present invention, the process of analyzing the removal of cold steel by visual monitoring when the cold steel is melted includes: installing a high-definition camera in the RH vacuum tank to collect images and transmit them to the remote control center, and the image processing system analyzes the removal of the cold steel. The high-definition cameras are distributed at key positions with a field of view of 60-90 degrees; the image recognition accuracy is ±2 kg.

[0044] In one embodiment, the method further comprises: in step S2, when the cold steel is melted, automatically operating the dust removal facility to process the smoke, wherein the dust collection pipeline, the status of the fan equipment and the processing data are transmitted to the remote central control center, wherein the fan automatically adjusts the power according to the feedback of the smoke concentration sensor.

[0045] In the present invention, the method further includes: after the cold steel is removed, refractory materials are built outside the RH vacuum tank body. In the present invention, non-destructive testing technology is used to automatically detect the RH vacuum tank refractory materials, and the results are transmitted to the remote control center to provide a basis for the refractory materials that need to be removed and replaced before building. Among them, the non-destructive testing technology can be infrared thermal imaging, which can detect the temperature distribution and thickness changes of the refractory materials with an accuracy of ±0.1 mm. When the refractory material is detected to be intact, it does not need to be replaced or built; when the refractory material is detected to be corroded, it needs to be replaced or built.

[0046] The method for removing cold steel from the RH vacuum tank off-line provided by the present invention does not require cleaning of the cold steel in the tank body before the tank body is offline when replacing the vacuum tank, so that the replacement of the vacuum tank can be completed quickly, so that the RH production can be seamlessly connected, thereby achieving the production plan and variety fulfillment. Specifically, the stable and efficient removal of cold steel (for example, about 1 ton per minute) is achieved by innovatively adopting off-line automated slag operation and innovative slag-removing process technology combination to overcome the low efficiency of the traditional vacuum tank online cold steel removal method, so that the vacuum tank can be restored to a normal usable state as soon as possible, and the production interruption time caused by replacing the vacuum tank online to process cold steel is reduced. At the same time, the equipment parameters are accurately adjusted with the help of the automation system and sensors, and the operation is adapted to different cold steel conditions in combination with visual monitoring, avoiding imprecise manual operation and preventing excessive or incomplete removal from damaging the vacuum tank. Innovative cold steel removal processes (such as coal oxygen baking and oxygen blowing technology) are used to accurately control parameters to reduce refractory erosion, reduce the erosion rate by 30%-50%, reduce the frequency and cost of refractory replacement, avoid the safety risks of manual cold steel removal to ensure the safety of operators, and reduce the emission of waste gas and smoke through precise control to achieve a win-win situation for environmental protection and economy.

[0047] The process of removing cold steel outside the RH vacuum tank provided by the present invention has significant implementation effects, realizing seamless docking vacuum tank replacement to promote the overall efficiency of the RH furnace, precise temperature control of the slag top gun to promote efficient melting of cold steel, continuity of automated operations such as slag connection, and visual monitoring to assist strategy adjustment, speed up the process and shorten the cycle. In terms of quality assurance, top gun temperature control ensures the quality of cold steel removal, non-destructive testing is beneficial to refractory material processing, environmentally friendly utilization of slag improves resource recovery rate and reduces cost consumption, dust removal facilities effectively control smoke and dust, slag recovery reduces emissions, and supports stable implementation of the process.

[0048] The present invention will be described in detail below by way of examples, but the protection scope of the present invention is not limited thereto. In the following examples, unless otherwise specified, the processes used are conventional operations.

[0049] Example 1

[0050] Off-line preparation:

[0051] The automated control system directs the transfer vehicle to move the RH vacuum tank to the off-line area (non-production area) at a speed of 1.2 m / s. The cold steel is inspected by ultrasonic testing equipment with an accuracy of ±5 mm to determine that the cold steel is at the bottom of the tank. The estimated amount of cold steel is 80 tons, and the data is transmitted to the remote center.

[0052] Cold Steel Removal:

[0053] (1) Preparation

[0054] The slag receiving device is operated according to the remote command to reach the cold steel position. The slag receiving device is a ladle car with a slag receiving pot. The slag receiving pot is placed under the RH vacuum tank to receive the molten cold steel and slag. The slag receiving pot is lifted to a suitable position according to the lifting method during the treatment of molten steel to ensure that the immersion depth meets the requirements, usually greater than 400mm. The slag receiving pot is automatically replaced when it is full. The cold steel slag in the slag receiving pot can be subsequently processed to achieve environmental protection and recycle cold steel resources.

[0055] Check the top gun equipment to ensure that it can work properly, including whether the gun body is damaged, whether the nozzle is blocked, etc. At the same time, check the oxygen pipeline and gas pipeline to ensure that the valve switch is flexible and there is no leakage.

[0056] Turn on relevant detection instruments, such as oxygen concentration test instruments, to monitor the oxygen content in the working environment in real time.

[0057] (2) Specific process of cold steel melting

[0058] In the fully automatic mode, the remote control center remotely sets the flow ratio of gas to oxygen to 1:1.4 based on the estimated amount of cold steel. According to the set ratio of gas to oxygen, the gas valve is opened first, and then the oxygen valve is opened to perform the ignition operation, ignite the coal-oxygen mixed gas sprayed from the top gun, and bake the cold steel in the RH vacuum tank.

[0059] According to the position and distribution of the cold steel in the vacuum tank, the top gun position is set according to the principle of "high first and low later". At the beginning, the top gun is placed at a higher position and baked with a larger gas and oxygen flow rate to make the cold steel initially heated and softened.

[0060] As the baking progresses, the gun position is gradually lowered, and the flow rates of coal gas and oxygen are adjusted in time according to the melting conditions of the cold steel, so that the heat generated by the combustion of coal and oxygen can be effectively transferred to the cold steel, accelerating the melting of the cold steel.

[0061] When liquid slag flows out of the insertion tube, the top gun position is further adjusted with a range of 300 mm each time. It can be adjusted 3 times during oxygen blowing, and each adjustment is maintained for 18 minutes to ensure that the cold steel can be fully melted and fall off the tank wall.

[0062] During the coal oxygen baking operation to heat and melt the cold steel, the heating temperature is controlled at around 1300°C. The heating temperature is monitored and fed back by a temperature sensor (accuracy ±5°C), and the remote control system adjusts the heating power to prevent overheating.

[0063] When cold steel is melting, dust removal facilities are automatically operated to treat smoke and dust. The dust collection pipeline, fan equipment status and processing data are transmitted to the remote central control center, and the fan automatically adjusts power according to the feedback from the smoke and dust concentration sensor.

[0064] When the cold steel is melting, a high-definition camera is installed in the RH vacuum tank to collect images and transmit them to the remote control center, and the image processing system analyzes the cold steel removal situation.

[0065] (3) End the operation

[0066] When the cold steel is basically melted and removed, close the gas valve first, then close the oxygen valve, and stop the coal-oxygen baking operation.

[0067] Open the nitrogen protective gas of the top gun, and the nitrogen flow rate is 150m 3 / h, purge for 10 minutes to reduce the oxygen concentration in the vacuum chamber and prevent residual oxygen from reacting with the equipment or the surrounding environment.

[0068] After the oxygen concentration in the vacuum chamber decreases, the top gun is lifted to the standby position, and finally the slag tank is removed, and the equipment and the work site are cleaned and inspected to prepare for the next operation.

[0069] Cleaning and post-processing:

[0070] High-pressure air blowing combined with manual inspection and cleaning, and infrared thermal imaging detection confirmed that the refractory material was intact and did not need to be replaced.

[0071] The effects of this embodiment are as follows: the cold steel processing time is shortened to 2 hours, the daily output is increased by 18%, the energy consumption is reduced by 8%, the emission meets the standard, and the life of the RH vacuum tank is extended.

[0072] Example 2

[0073] Off-line preparation:

[0074] The automated control system directs the transfer vehicle to move the RH vacuum tank to the off-line area (non-production area) at a speed of 1.8 m / s. The cold steel is inspected by ultrasonic testing equipment with an accuracy of ±5 mm to determine the location of the cold steel on the tank wall and bottom. The estimated amount of cold steel is 130 tons, and the data is transmitted to the remote center.

[0075] Cold Steel Removal:

[0076] (1) Preparation

[0077] The slag receiving device is operated according to the remote command to reach the cold steel position. The slag receiving device is a ladle car with a slag receiving pot. The slag receiving pot is placed under the RH vacuum tank to receive the molten cold steel and slag. The slag receiving pot is lifted to a suitable position according to the lifting method during the treatment of molten steel to ensure that the immersion depth meets the requirements, usually greater than 400mm. The slag receiving pot is automatically replaced when it is full. The cold steel slag in the slag receiving pot can be subsequently processed to achieve environmental protection and recycle cold steel resources.

[0078] Check the top gun equipment to ensure that it can work properly, including whether the gun body is damaged, whether the nozzle is blocked, etc. At the same time, check the oxygen pipeline and gas pipeline to ensure that the valve switch is flexible and there is no leakage.

[0079] Turn on relevant detection instruments, such as oxygen concentration test instruments, to monitor the oxygen content in the working environment in real time.

[0080] (2) Specific process of cold steel melting

[0081] In the fully automatic mode, the remote control center remotely sets the flow ratio of gas to oxygen to 1:1.4 based on the estimated amount of cold steel. According to the set ratio of gas to oxygen, the gas valve is opened first, and then the oxygen valve is opened to perform the ignition operation, ignite the coal-oxygen mixed gas sprayed from the top gun, and bake the cold steel in the RH vacuum tank.

[0082] According to the position and distribution of the cold steel in the vacuum tank, the top gun position is set according to the principle of "high first and low later". At the beginning, the top gun is placed at a higher position and baked with a larger gas and oxygen flow rate to make the cold steel initially heated and softened.

[0083] As the baking progresses, the gun position is gradually lowered, and the flow rates of coal gas and oxygen are adjusted in time according to the melting conditions of the cold steel, so that the heat generated by the combustion of coal and oxygen can be effectively transferred to the cold steel, accelerating the melting of the cold steel.

[0084] When liquid slag flows out of the insertion tube, further adjust the top gun position, each adjustment range is 400mm. It can be adjusted twice during oxygen blowing, each time for 15 minutes to ensure that the cold steel can be fully melted and fall off the tank wall.

[0085] During the coal oxygen baking operation to heat and melt the cold steel, the heating temperature is controlled at around 1300°C. The heating temperature is monitored and fed back by a temperature sensor (accuracy ±5°C), and the remote control system adjusts the heating power to prevent overheating.

[0086] When cold steel is melting, dust removal facilities are automatically operated to treat smoke and dust. The dust collection pipeline, fan equipment status and processing data are transmitted to the remote central control center, and the fan automatically adjusts power according to the feedback from the smoke and dust concentration sensor.

[0087] When the cold steel is melting, a high-definition camera is installed in the RH vacuum tank to collect images and transmit them to the remote control center, and the image processing system analyzes the cold steel removal situation.

[0088] (3) End the operation

[0089] When the cold steel is basically melted and removed, close the gas valve first, then close the oxygen valve, and stop the coal-oxygen baking operation.

[0090] Open the nitrogen protective gas of the top gun, the nitrogen flow rate is 200m 3 / h, purge for 15 minutes to reduce the oxygen concentration in the vacuum chamber and prevent residual oxygen from reacting with the equipment or the surrounding environment.

[0091] After the oxygen concentration in the vacuum chamber decreases, the top gun is lifted to the standby position, and finally the slag tank is removed, and the equipment and the work site are cleaned and inspected to prepare for the next operation.

[0092] Cleaning and post-processing:

[0093] High-pressure air blowing combined with manual inspection and cleaning, and infrared thermal imaging detection to ensure that the refractory material is not damaged.

[0094] The effects of this embodiment are as follows: the cold steel processing time is shortened to 2.5 hours, the daily output is increased by 22%, the energy consumption is reduced by 12%, the emission meets the standard, and the equipment stability is enhanced.

[0095] It can be seen from the examples that the method for removing cold steel off-line using the RH vacuum tank described in the present invention can greatly improve the cold steel removal efficiency, significantly shorten the cold steel processing time, and at the same time significantly increase the daily output of the production line and significantly reduce energy consumption.

[0096] It should be understood that parts not elaborated in detail in this specification belong to the prior art.

[0097] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for removing cold steel outside the RH vacuum tank line, characterized in that: The method comprises the following steps: S1. Move the RH vacuum tank to a non-production area, inspect the cold steel, and determine the cold steel location and estimated cold steel quantity; S2. The slag receiving device runs according to remote instructions to reach the cold steel position to receive the molten cold steel; in the fully automatic mode, the top gun parameters are set remotely according to the estimated amount of cold steel, and the top gun works according to the remote parameters to heat and melt the cold steel through coal oxygen baking operation; when the cold steel is melted, the cold steel removal situation is analyzed through visual monitoring, and the feedback results are used for the central remote adjustment strategy.

2. The method according to claim 1, characterized in that In step S1, the transfer equipment is directed by the automated control system to move the RH vacuum tank to a non-production area; And / or, in step S1, the process of detecting the cold steel includes: automatically detecting the cold steel using ultrasonic detection equipment.

3. The method according to claim 1 or 2, characterized in that: In step S2, the top gun parameters include a set flow ratio of coal gas to oxygen.

4. The method according to claim 3, characterized in that The set flow ratio of coal gas to oxygen is 1:1~2.

5. The method according to claim 4, characterized in that In step S2, the process of heating and melting the cold steel through the coal-oxygen baking operation includes: according to the set flow ratio of coal gas to oxygen, first opening the gas valve, then opening the oxygen valve, performing the ignition operation, igniting the coal-oxygen mixed gas sprayed from the top gun, and baking the cold steel in the RH vacuum tank.

6. The method according to claim 1, characterized in that In step S2, the heating temperature for heating and melting the cold steel is 1250-1350°C.

7. The method according to claim 1, characterized in that The method further comprises: in step S2, when the cold steel is melted, automatically operating dust removal facilities to process smoke.

8. The method according to claim 1, characterized in that In step S2, the process of analyzing the removal of cold steel by visual monitoring when the cold steel is melted includes: installing a high-definition camera in the RH vacuum tank to collect images and transmit them to the remote control center, and the image processing system analyzes the removal of the cold steel.

9. The method according to claim 1, characterized in that: The method also includes: after the cold steel is removed, refractory materials are built outside the RH vacuum tank body.

10. The method according to claim 9, characterized in that Non-destructive testing technology is used to automatically test the RH vacuum tank refractory materials, and the results are transmitted to the remote control center to provide a basis for the refractory materials that need to be removed and replaced before masonry.