Automatic control method in ladle argon blowing process

Abstract

The invention discloses an automatic control method in a steel ladle argon blowing process, relates to the technical field of automatic control in the metallurgical industry, and researches three argon blowing modes, namely a low-iron-consumption refining mode, a shallow treatment mode and an argon blowing straight-up mode, according to actual production process requirements. A whole set of steel ladle automatic argon blowing control is realized on the basis that the flow, the pressure and the argon blowing time of argon are controlled by a PLC (Programmable Logic Controller), the walking of a buggy ladle and the control of a vibrating feeder for cooling materials behind a furnace and a temperature measuring and sampling robot, so that an argon blowing control mode meeting different production requirements is realized, and the stability of the temperature of the steel ladle and the full mixing of molten steel in different modes are realized; and the quality of molten steel stirred by argon when the steel ladle does not pass through the treatment mode is improved.

Description

Technical Field

[0001] The present application relates to the technical field of automatic control in the metallurgical industry, and in particular to an automatic control method in a ladle argon blowing process. Background Art

[0002] Argon blowing from the bottom of the ladle is one of the important links to ensure the quality of molten steel. By blowing argon into the bottom or top of the ladle, the molten steel is boiled, so as to achieve the purpose of uniform chemical composition and temperature of the molten steel, accelerate chemical reactions, remove harmful gases and inclusions, and purify the molten steel. By controlling the pressure and time of argon blowing, precise control of the molten steel can be achieved. Ladle argon blowing treatment is widely used in various steel production processes, especially in situations where harmful gases and inclusions need to be removed. Through argon blowing treatment, the quality and purity of steel can be effectively improved to meet high-standard production requirements. If the amount of argon, the blowing time and the amount of cold material added during the ladle argon blowing process are not properly controlled, not only will the molten steel slag roll and the insufficient removal of inclusions will occur, but also the quality of the molten steel will be deteriorated.

[0003] In traditional technology, steel mills have always controlled and adjusted the amount of argon gas blown at the bottom of the ladle, the blowing time and the amount of cold material input through manual experience. However, due to the uneven manual experience, the control of the amount of gas or the amount of cold material added is not accurate, and there is no standard value, which occasionally causes molten steel quality problems such as uneven molten steel temperature and segregation of molten steel components. In addition, the original argon blowing process is manually operated to collect the composition and temperature of the molten steel. The argon blowing point is close to the ladle, the environment is harsh, and the employees who operate the argon blowing are at safety risk. Chinese patent CN112410510B discloses a method and system for automatic argon blowing of a ladle. The method for automatic argon blowing of a ladle provided realizes automatic argon blowing of the entire process from the beginning of steel tapping to the ladle before the continuous casting machine, reduces the labor intensity of the staff, and improves the safety of the automatic argon blowing operation. Chinese patent CN104073588B discloses a method for automatic control of argon blowing at the bottom of a converter ladle, which realizes full automatic control of argon blowing at the bottom of a converter ladle, reduces the labor intensity of the operator, standardizes the bottom argon blowing operation, and improves the quality of argon-stirred molten steel.

[0004] The above-mentioned argon blowing automatic control method realizes the automation of argon blowing of the ladle, and the focus is on how to achieve accurate argon blowing parameters to improve the effect of argon blowing of the ladle. However, in the metal smelting converter, there are cases where the ladle enters the refining furnace or does not need to be refined, and the argon blowing methods in different cases are also different. Summary of the invention

[0005] In order to solve the above technical problems, this application proposes the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides an automatic control method in a ladle argon blowing process, comprising:

[0007] Determine the flow rate, pressure and time setting values ​​for different argon blowing processes corresponding to different steel grades;

[0008] After the ladle car arrives at the argon blowing position, an argon blowing operation is performed in accordance with the selected argon blowing mode, the set pressure, flow rate and set time;

[0009] When the argon blowing operation is continued until the temperature measurement stage, a signal is sent to the robot, and the robot holds the temperature measuring rod and extends it into the ladle for temperature measurement. After the temperature measurement is completed, the temperature measurement data is transmitted to the PLC to wait for the next temperature measurement instruction.

[0010] After receiving the temperature measurement data, the PLC automatically finds the cold material discharge value corresponding to the corresponding temperature range according to the temperature measurement value, sends a vibration start command to the vibrating feeder behind the furnace, and sends a vibration stop signal when the discharge cut-off value is reached;

[0011] After receiving the vibration stop signal from the vibrating feeder, the argon blowing mode switches to the large argon stirring mode and blows the corresponding set argon volume according to the set time;

[0012] Finally, different temperature measurements and subsequent argon blowing treatments are performed according to the subsequent treatment mode of the ladle after being treated in the large argon stirring mode.

[0013] In a possible implementation, after the ladle is treated in the large argon stirring mode, the treatment modes include: low iron consumption refining mode, shallow treatment mode and argon blowing straight up mode, according to whether the ladle is to be refined, wherein: the ladle entering the low iron consumption refining mode enters the refining furnace for refining, the ladle entering the shallow treatment mode determines whether to enter the refining furnace for refining according to production demand, and the ladle entering the argon blowing straight up mode does not enter the refining furnace for refining.

[0014] In one possible implementation, if the ladle enters the low iron consumption refining mode after being treated in the high argon stirring mode, after receiving the vibration stop signal of the vibrating feeder, the ladle car sends a signal to advance to the cover position. When it reaches the position, the argon blowing flow and pressure are all automatically set to 0, and the automatic argon blowing process ends.

[0015] In one possible implementation, if the ladle enters the shallow treatment mode and the argon blowing straight-up mode after being treated in the large argon stirring mode, after the timing of the large argon stirring mode ends, the robot is controlled to perform a second temperature measurement and a sampling operation. After the argon blowing is switched to the temperature measurement and sampling mode for inspection, the test results are automatically uploaded to the control center for optimizing the composition ratio of the next batch of molten steel.

[0016] In a possible implementation, after the secondary temperature measurement and the primary sampling are completed, if the ladle enters the shallow processing mode, the ladle car sends a signal to advance to the cover-adding position. When it reaches the position, the argon blowing flow and pressure are automatically set to 0, and the automatic argon blowing process ends.

[0017] In one possible implementation, after the secondary temperature measurement and sampling is completed, if the ladle enters the argon blowing straight-up mode, it is necessary to carry out secondary feeding to adjust the molten steel composition according to the test results, control the robot to perform the third temperature measurement and secondary sampling, and then the ladle car sends a signal to move forward to the cover-opening position. When it is in place, the argon blowing flow and pressure are automatically set to 0, and the automatic argon blowing process ends.

[0018] In the embodiments of the present application, according to the actual production process requirements, three argon blowing modes are studied: low iron consumption refining mode, shallow treatment mode and argon blowing straight up mode. Based on PLC control of argon flow, pressure, argon blowing time, movement of the ladle car, vibrating feeder of the cold material behind the furnace and robot control of temperature measurement and sampling, a complete set of automatic argon blowing control for the ladle is realized, and argon blowing control modes that meet different production requirements are realized. The stability of the ladle temperature and the sufficient mixing of the molten steel in different modes are achieved, and the quality of the argon stirring molten steel in the ladle non-processing mode is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic flow chart of an automatic control method for a ladle argon blowing process provided in an embodiment of the present application;

[0020] Figure 2 A control interface diagram of a robot provided in an embodiment of the present application for controlling temperature measurement and sampling;

[0021] Figure 3 A schematic diagram of the argon blowing process of the ladle in the low iron consumption refining mode provided in an embodiment of the present application;

[0022] Figure 4 A schematic diagram of the ladle argon blowing process for the shallow treatment mode provided in an embodiment of the present application;

[0023] Figure 5 This is a schematic diagram of the argon blowing process of the ladle in the argon blowing straight-up mode provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] The present solution is described below in conjunction with the accompanying drawings and specific implementation methods.

[0025] See also Figure 1 The automatic control method for the ladle argon blowing process provided in this embodiment includes:

[0026] S101, determining flow rate, pressure and time setting values ​​in different argon blowing processes corresponding to smelting of different steel grades.

[0027] S102, after the ladle car arrives at the argon blowing position, an argon blowing operation is performed in accordance with the selected argon blowing mode in sequence according to the set pressure, flow rate and set time.

[0028] S103, when the argon blowing operation is maintained until the temperature measurement stage, a signal is sent to the robot, and the robot clamps the temperature measuring rod and extends it down into the ladle to measure the temperature. After the temperature measurement is completed, the temperature measurement data is transmitted to the PLC to wait for the next temperature measurement instruction.

[0029] S104, after receiving the temperature measurement data, the PLC automatically finds the cold material discharge value corresponding to the corresponding temperature range according to the temperature measurement value, sends a vibration start command to the vibrating feeder behind the furnace, and sends a vibration stop signal when the discharge cut-off value is reached.

[0030] S105, after receiving the vibration stop signal of the vibrating feeder, the argon blowing is switched to a large argon stirring mode, and the corresponding set argon volume is blown according to the set time.

[0031] S106, finally, different temperature measurements and subsequent argon blowing treatments are performed according to the subsequent treatment modes of the ladle after the treatment in the large argon stirring mode.

[0032] See also Figure 2 , Control of the temperature measurement and sampling robot: According to the process, send temperature measurement or sampling signals to the robot, the robot automatically enters the ladle car to work and transmit data.

[0033] In the present embodiment, after the ladle is treated in the large argon stirring mode, the treatment modes include: low iron consumption refining mode, shallow treatment mode and argon blowing straight up mode, according to whether the ladle is to be refined, wherein: the ladle entering the low iron consumption refining mode enters the refining furnace for refining, the ladle entering the shallow treatment mode determines whether to enter the refining furnace for refining according to production demand, and the ladle entering the argon blowing straight up mode does not enter the refining furnace for refining.

[0034] Further, if the ladle enters the low iron consumption refining mode after the high argon stirring mode treatment, see Figure 3 After receiving the vibration stop signal from the vibrating feeder, the ladle car sends a signal to move forward to the cover opening position. When it reaches the position, the argon blowing flow and pressure are all automatically set to 0, and the automatic argon blowing process ends.

[0035] The low iron consumption refining mode is suitable for the secondary processing of molten steel into the refining furnace after argon blowing, with the goal of reducing iron consumption and improving the purity of molten steel. PLC achieves gentle stirring and degassing of molten steel by accurately controlling the flow and pressure of nitrogen and argon, avoiding increased iron consumption caused by excessive stirring.

[0036] If the ladle enters the shallow treatment mode and argon blowing straight up mode after being treated in the large argon stirring mode, the robot is controlled to perform secondary temperature measurement and primary sampling after the timing of the large argon stirring mode ends. After the argon blowing is switched to the temperature measurement and sampling mode and the inspection is completed, the test results are automatically uploaded to the control center for optimizing the composition ratio of the next batch of molten steel.

[0037] See also Figure 4After the secondary temperature measurement and primary sampling are completed, if the ladle enters the shallow processing mode, the ladle car sends a signal to move forward to the cover-adding position. When it is in place, the argon blowing flow and pressure are automatically set to 0, and the automatic argon blowing process ends.

[0038] The shallow treatment mode is suitable for the scene of preliminary treatment of molten steel. The flow rate and pressure of argon are controlled by PLC to achieve slight stirring and degassing of the molten steel surface. The flow rate and pressure parameters are set according to the steel type and process requirements to ensure the stability of the molten steel quality.

[0039] See also Figure 5 After the secondary temperature measurement and sampling is completed, if the ladle enters the argon blowing straight up mode, it is necessary to carry out secondary feeding to adjust the molten steel composition according to the test results, control the robot to perform three temperature measurement and secondary sampling, and then the ladle car sends a signal to move forward to the cover opening position. When it is in place, the argon blowing flow and pressure are automatically set to 0, and the automatic argon blowing process ends.

[0040] In this mode, the molten steel no longer enters the refining furnace for secondary processing. It has higher requirements for the argon blowing mode. There will be three temperature measurements, two samplings, and two feedings for the molten steel mode processing to ensure the stability of the molten steel temperature and composition.

[0041] In this embodiment, the PLC hardware configuration is composed of Siemens S7-1500, the argon blowing regulating valve opening control is all collected and calculated by 1512 series CPU, the robot is controlled by 1516 series CPU, and the vibrating feeder and ladle car are controlled by 1517 series CPU. The program is implemented through Siemens automation programming software Botu ladder diagram, the programming module is independent, and the program is simple and efficient. The upper computer monitoring uses Siemens WINCC7.5.1 screen editing software, which has the functions of collecting variable trends and printing reports.

[0042] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0043] The above is only a specific implementation of the present application. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. The protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An automatic control method for ladle argon blowing process, characterized in that: include: Determine the flow rate, pressure and time setting values ​​for different argon blowing processes corresponding to different steel grades; After the ladle car arrives at the argon blowing position, an argon blowing operation is performed in accordance with the selected argon blowing mode, the set pressure, flow rate and set time; When the argon blowing operation is continued until the temperature measurement stage, a signal is sent to the robot, and the robot holds the temperature measuring rod and extends it into the ladle for temperature measurement. After the temperature measurement is completed, the temperature measurement data is transmitted to the PLC to wait for the next temperature measurement instruction. After receiving the temperature measurement data, the PLC automatically finds the cold material discharge value corresponding to the corresponding temperature range according to the temperature measurement value, sends a vibration start command to the vibrating feeder behind the furnace, and sends a vibration stop signal when the discharge cut-off value is reached; After receiving the vibration stop signal from the vibrating feeder, the argon blowing mode switches to the large argon stirring mode and blows the corresponding set argon volume according to the set time; Finally, different temperature measurements and subsequent argon blowing treatments are performed according to the subsequent treatment mode of the ladle after being treated in the large argon stirring mode.

2. The automatic control method in the ladle argon blowing process according to claim 1, characterized in that: After the ladle is treated in the large argon stirring mode, depending on whether it is to be refined, the treatment modes include: low iron consumption refining mode, shallow treatment mode and argon blowing straight up mode, wherein: the ladle entering the low iron consumption refining mode enters the refining furnace for refining, the ladle entering the shallow treatment mode determines whether to enter the refining furnace for refining according to production demand, and the ladle entering the argon blowing straight up mode does not enter the refining furnace for refining.

3. The automatic control method in the ladle argon blowing process according to claim 2, characterized in that: If the ladle enters the low iron consumption refining mode after being treated in the large argon stirring mode, after receiving the vibration stop signal of the vibrating feeder, the ladle car sends a signal to move forward to the cover opening position. When it reaches the position, the argon blowing flow and pressure are all automatically set to 0, and the automatic argon blowing process ends.

4. The automatic control method in the ladle argon blowing process according to claim 2, characterized in that: If the ladle enters the shallow treatment mode and argon blowing straight up mode after being treated in the large argon stirring mode, the robot is controlled to perform secondary temperature measurement and primary sampling after the timing of the large argon stirring mode ends. After the argon blowing is switched to the temperature measurement and sampling mode and the inspection is completed, the test results are automatically uploaded to the control center for optimizing the composition ratio of the next batch of molten steel.

5. The automatic control method in the ladle argon blowing process according to claim 4, characterized in that: After the secondary temperature measurement and primary sampling are completed, if the ladle enters the shallow processing mode, the ladle car sends a signal to move forward to the cover-adding position. When it reaches the position, the argon blowing flow and pressure are automatically set to 0, and the automatic argon blowing process ends.

6. The automatic control method in the ladle argon blowing process according to claim 4, characterized in that: After the secondary temperature measurement and sampling is completed, if the ladle enters the argon blowing straight up mode, it is necessary to carry out secondary feeding to adjust the molten steel composition according to the test results, control the robot to perform three temperature measurement and secondary sampling, and then the ladle car sends a signal to move forward to the cover opening position. When it is in place, the argon blowing flow and pressure are automatically set to 0, and the automatic argon blowing process ends.

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