CN118122977A - Method for reducing slag rolling of sheet billet continuous casting machine - Google Patents
Method for reducing slag rolling of sheet billet continuous casting machine Download PDFInfo
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Abstract
The invention discloses a method for reducing slag rolling of a sheet billet continuous casting machine, which comprises the following steps: cleaning the tundish by using a dust collector, controlling the flow of argon blown into the continuous casting machine, and deslagging, supplementing a covering agent and casting according to a preset strategy so as to reduce molten steel pollution; calculating a crystallizer liquid level parameter of the continuous casting machine through frequency and pull speed, and controlling the crystallizer liquid level to be in a preset fluctuation range; when the water immersion depth of the crystallizer is smaller than a threshold value, controlling electromagnetic braking compensation current, and reducing the flow rate of molten steel in the crystallizer to a preset range; when the continuous casting machine detects that the quantity of the nozzle eye-drop is increased in the casting process, signals are sent to a refining main control device and a rolling mill main control device of the continuous casting machine; and responding to the signal, controlling the detection equipment to detect the surface quality of the steel coil corresponding to the heat, and feeding the data of the detected slag rolling phenomenon back to the terminal. By reducing the occurrence of slag rolling, accidents caused by slag rolling are reduced, and the product quality is improved.
Description
Technical Field
The invention relates to the technical field of ferrous metallurgy, in particular to a method for reducing slag coiling of a sheet billet continuous casting machine.
Background
In the production process of the sheet bar continuous casting machine, with continuous lifting of the pulling speed, high speed exceeding 6 m/min is achieved at present, which clearly improves the production efficiency. However, this high-speed production also presents new challenges, especially in cases of poor control of the cleanliness of the molten steel, unstable casting conditions due to variations in the drawing speed and anomalies in the cooling system of the crystalliser, the risk of slag inclusions in the continuous casting slab increases significantly. Slag inclusion defects, i.e., oxides adhering to the surface of the steel slab, have been key factors affecting the surface quality of the strip steel. Since these defects are difficult to eliminate during subsequent processing, and as the reduction increases, the slag inclusion defects may further amplify. This not only results in degradation of the product due to substandard surface quality, increasing the rejection rate, but also may affect on-time delivery of the product, even in extreme cases, causing safety accidents such as casting machine steel leakage or rolling mill steel piling. Therefore, how to effectively control and reduce the slag coiling defect becomes a technical problem to be solved in the continuous casting machine production.
Disclosure of Invention
The embodiment of the invention solves the technical problem that the continuous casting machine has slag rolling defects in the prior art by providing the slag rolling reduction method of the sheet billet continuous casting machine, realizes the reduction of accidents caused by slag rolling, and improves the product quality.
In order to solve the technical problems, the invention provides the following technical scheme:
in a first aspect, the invention discloses a method for reducing slag from a thin slab caster, comprising:
cleaning particles in the tundish by using a dust collector, controlling the flow of argon blown into the continuous casting machine, and deslagging, supplementing a covering agent and casting according to a preset strategy so as to reduce molten steel pollution;
Calculating the crystallizer liquid level parameter of the continuous casting machine through frequency and pull speed, and controlling the crystallizer liquid level to be in a preset fluctuation range; when the depth of the immersed opening of the crystallizer is smaller than a threshold value, controlling electromagnetic braking compensation current, and reducing the flow rate of molten steel in the crystallizer to a preset range;
When the casting process of the continuous casting machine detects that the quantity of the nozzle eye-drop is increased, signals are sent to a refining main control device and a rolling mill main control device of the continuous casting machine; and responding to the signals, controlling the detection equipment to detect the surface quality of the steel coil corresponding to the heat, and feeding the data of the detected slag rolling phenomenon back to the terminal.
Optionally, the step of controlling the flow rate of the argon blown into the continuous casting machine further includes:
Before the continuous casting machine is started, argon is blown into a tundish of the continuous casting machine until the volume fraction of the oxidizing gas is reduced below a threshold value, so that the gas replacement efficiency in the tundish is improved.
Optionally, the step of controlling the flow rate of the argon blown into the continuous casting machine further includes:
And controlling the argon blowing flow of the ladle long nozzle of the continuous casting machine to a preset range so as to reduce the liquid level rising of an argon impact area.
Optionally, the steps of deslagging, supplementing covering agent and casting according to a preset strategy specifically comprise:
When the continuous casting machine is started and the second furnace is started, deslagging is carried out on the tundish, and a covering agent is added again;
Replacing the sealing ring of the long water gap every furnace, discharging slag once every preset number of furnace times, and prompting slag discharge if steel slag flowing into the tundish from the ladle is detected;
When the tonnage of the starting furnace tundish is larger than the preset weight, opening a stopper rod for casting;
And when the slag quantity ratio is detected to be larger than the preset percentage, reducing the slag quantity of the tundish until the slag quantity ratio is lower than the preset percentage.
Optionally, the step of calculating the crystallizer liquid level parameter of the continuous casting machine by the passing frequency and the pulling speed specifically includes:
for liquid level fluctuation of fixed frequency, calculating the position generating the liquid level fluctuation according to the frequency and the pulling speed, and increasing the preset secondary cooling intensity to avoid high-frequency liquid level fluctuation.
Optionally, the step of controlling the liquid level of the crystallizer within a preset fluctuation range further includes:
The immersed nozzle of the crystallizer is centered by laser, so that the drift of molten steel is avoided.
Optionally, after the reducing the flow rate of the molten steel in the crystallizer to the preset range, the method further includes:
When the continuous casting machine just starts to run, when the eye-covering phenomenon is detected, the rod shaking is started, and the eye-covering is eliminated through vibration.
Optionally, the method further comprises:
And in the stage of the crystallizer inspection, controlling the movement of the end part of the spot inspection rod on the liquid slag layer so as to reduce slag coiling caused by the contact of the head of the spot inspection rod with molten steel.
Optionally, the method further comprises:
In the stage of expanding and pulling speed at the initial stage of casting, judging waste of the casting blank based on a wedge-shaped waste judging principle according to the shape and the size of the casting blank;
Determining a corresponding pouring length threshold based on the waste judgment data; and controlling the pouring length to finish the treatment of the cold steel and slag strips before the pouring length threshold value is reached.
Optionally, the method further comprises:
In a preset area taking the immersed nozzle of the crystallizer as the center, a long roller of a slag picking roller is adopted to pick liquid slag from outside to inside so as to cover all positions;
In the region far away from the immersed nozzle in the crystallizer, picking liquid slag by using a right-angle slag picking rod; and acquiring the state of the right-angle slag picking rod in real time, and judging the maximum depth of slag picking operation when the right-angle slag picking rod vibrates.
One or more technical schemes provided by the invention have at least the following technical effects or advantages:
The technical scheme of the invention aims to reduce slag rolling defects and improve the quality of casting blanks. In the continuous casting process, ensuring the quality of casting blanks is important for the subsequent rolling process. Firstly, the dust collector is used for cleaning the particulate matters in the tundish, so that the impurities carried by molten steel in the flowing process can be effectively reduced, and the generation of slag is reduced. And secondly, controlling the flow of argon blown into the continuous casting machine, and carrying out slag discharging, covering agent supplementing and casting starting operations according to a preset strategy. The measures are helpful for reducing the pollution of molten steel in the casting process, ensuring the purity of the molten steel, and improving the overall quality of casting blanks. In addition, the probability of slag coiling can be further reduced by precisely controlling the liquid level in the crystallizer to keep the liquid level in a preset fluctuation range. The method not only reduces the quantity of carried-out products and improves the product qualification rate of the production line, but also reduces the safety accident risk caused by slag coiling. Meanwhile, the scheme also comprises the steps of detecting the quantity of the nozzle eye rod in the casting process of the continuous casting machine and monitoring the surface quality of the steel coil of the corresponding heat by using detection equipment. The quality problem of the slab continuous casting machine can be found and repaired in time by feeding the detected slag rolling phenomenon data back to the terminal, so that the surface quality of a final product is improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of a method for reducing slag from a sheet billet caster according to the present invention;
Fig. 2 is a schematic view of a mold of a thin slab caster according to the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, and not limited to the technical solutions of the present application, and the embodiments of the present application and the technical features in the embodiments may be combined with each other without conflict.
The embodiment of the invention solves the technical problem that the continuous casting machine has slag rolling defects in the prior art by providing the slag rolling reduction method of the sheet billet continuous casting machine, realizes the reduction of accidents caused by slag rolling, and improves the product quality.
In an embodiment of the present invention, a method for reducing slag of a thin slab caster as shown in fig. 1 is provided, and the method includes:
And step S101, cleaning particles in the tundish by using a dust collector, controlling the flow of argon blown into the continuous casting machine, and deslagging, supplementing a covering agent and casting according to a preset strategy so as to reduce molten steel pollution.
The cleaning method comprises the steps of cleaning a tundish by using a dust collector, and aims to clean particles in the tundish by using the dust collector, so that the pollution of molten steel is avoided by improving the standards of the cover and the cleanliness in the tundish. And then controlling the flow rate of argon blown into the continuous casting machine, and specifically: before the continuous casting machine is started, argon is blown into a tundish of the continuous casting machine until the volume fraction of the oxidizing gas is reduced below a threshold value, so that the gas replacement efficiency in the tundish is improved. Therefore, the external argon blowing pipe is increased to directly extend into the bottom of the tundish, the gas replacement efficiency and effect in the tundish are improved, and the volume fraction of the oxidizing gas in the tundish is reduced to below 0.1%. And controlling the argon blowing flow of the ladle long nozzle of the continuous casting machine to a preset range of 10Nm 3/h to 20Nm 3/h so as to reduce the liquid level of the argon impact area from rising.
In addition, slag is discharged according to a preset strategy, a covering agent is supplemented, and casting is started; specifically, when the continuous casting machine is started and the second furnace is started, slag is discharged from the tundish, and a sufficient amount of covering agent is added again. Replacing a sealing ring of a long water gap every furnace, deslagging every 4 heats, and prompting deslagging if steel slag flowing into a tundish from a ladle is detected; among them, for the detection of steel slag, various modes can be adopted, such as: 1. optical detection is adopted, namely, an optical sensor or a camera is used for monitoring the flow of molten steel in real time. And detecting impurities and bubbles in the molten steel so as to judge whether slag enters the tundish. 2. Ultrasonic detection is adopted: by installing an ultrasonic sensor at a specific position of the tundish, abnormal changes in the flow of molten steel such as abnormal fluctuations in flow velocity, flow rate or temperature are detected, thereby judging that slag enters the tundish. 3. Electromagnetic detection is adopted: the electromagnetic induction principle is utilized to change the distribution of an electromagnetic field based on impurities, and the nonmetallic impurities in the molten steel are detected by arranging electromagnetic coils around a ladle nozzle. 4. And (3) detecting by adopting a thermal imager: the thermal imager can detect the temperature distribution of molten steel, and the steel slag can show different temperature characteristics from normal molten steel on the thermal imager due to the lower melting point of the steel slag. 5. Chemical analysis was used: and judging the existence of steel slag by sampling and analyzing the chemical components of the molten steel. That is, steel slag is generally high in oxygen content, and the distribution of the steel slag is estimated by analyzing the oxygen content in the molten steel.
And when the tonnage of the starting furnace tundish is larger than the preset weight, opening a stopper rod for casting. The device aims to control the flow of molten steel and the floating of inclusions in a tundish, and prevent the inclusions from entering a nozzle or a crystallizer in the casting process to cause sleeve hole or slag rolling and steel leakage accidents.
And when the slag quantity ratio is detected to be larger than the preset percentage, reducing the slag quantity of the tundish until the slag quantity ratio is lower than the preset percentage. In the continuous casting process, excessive steel slag in the tundish can increase the impurity and gas content in the molten steel, thereby affecting the purity and quality of the molten steel. Meanwhile, excessive steel slag can cause excessive erosion to the refractory material of the tundish, so that the service life of the tundish is shortened. Therefore, in order to improve the quality of molten steel and prevent damage to equipment, the preset percentage is set to 10%, and the slag amount is controlled according to the preset percentage.
Step S102, calculating a crystallizer liquid level parameter of the continuous casting machine through frequency and pull speed, and controlling the crystallizer liquid level to be in a preset fluctuation range; when the water immersion depth of the crystallizer is smaller than a threshold value, controlling electromagnetic braking compensation current, and reducing the flow rate of molten steel in the crystallizer to a preset range;
The crystallizer liquid level parameter of the continuous casting machine is calculated through frequency and pulling speed, and is mainly controlled according to liquid level fluctuation of fixed frequency, namely, the position generating liquid level fluctuation is calculated according to frequency and pulling speed, and the high-frequency liquid level fluctuation caused by bulging, sector section deviation and the like is avoided by increasing the preset secondary cooling intensity. In the continuous casting process, bulging refers to a phenomenon that a casting blank bulges in the horizontal direction due to the action of hydrostatic pressure of molten steel in the solidification process. The segment deviation refers to the deviation of the position or shape of the casting blank caused by equipment failure or improper operation and the like when the casting blank passes through the segment in the direction of drawing the blank in the continuous casting machine. In order to alleviate the high-frequency liquid level fluctuation caused by the deviation of the belly and the sector section, the embodiment adopts measures for increasing the secondary cooling intensity. Through strengthening the cooling of casting blank, can reduce the bulging degree and the fan-shaped section deviation of casting blank to stabilize the crystallizer liquid level, improve the quality of casting blank and the production efficiency of conticaster. The strength of the secondary cooling is generally expressed in terms of specific water content in L/kg. The specific water amount refers to the ratio of the amount of cooling water consumed per unit time to the weight of the cast slab passing through the secondary cooling zone.
The step of controlling the crystallizer liquid level within a preset fluctuation range further comprises the following steps: the immersed nozzle of the crystallizer is centered by laser, so that the drift of molten steel is avoided. Among them, the submerged nozzle is an important component in the mold of the continuous casting machine, also called submerged nozzle jacket or submerged nozzle cup. It is located at the bottom of the mold for introducing molten steel from a ladle or tundish into the mold. The submerged nozzle is used for controlling the flow and direction of molten steel and helping to protect the copper wall of the crystallizer from direct scouring and erosion of high-temperature molten steel. In existing submerged entry nozzle designs, the molten steel, after exiting the submerged entry nozzle, passes through a relatively long passage before reaching the copper wall of the mould. Because the channel is longer, the drift phenomenon of molten steel flow is easy to cause, and the heat transfer and crystallization process of the crystallizer can be influenced, so that the quality of casting blanks is influenced. To address this problem, the present embodiment employs a laser precision centering technique to optimize the design and installation of the submerged entry nozzle. The technique ensures that the centering precision between the submerged nozzle and the copper wall of the crystallizer reaches millimeter level through a high-precision laser measurement and control system, thereby avoiding the drift phenomenon of molten steel flow. Based on the accurate centering and post-operation, the flow direction and the speed field of molten steel can be better controlled, and the heat transfer efficiency and the crystallization quality of the crystallizer are improved. In addition, the scouring and erosion to the copper wall of the crystallizer can be reduced by utilizing the laser to precisely center, and the service life of the crystallizer can be prolonged.
In addition, the step of reducing the flow rate of molten steel in the crystallizer to a preset range is to increase the electromagnetic braking compensation current by 30-50A when the depth of a soaking opening is smaller than 130mm, and reduce the flow rate of molten steel in the crystallizer. The principle is as follows: the depth of the submerged entry nozzle refers to the distance from the bottom of the submerged entry nozzle to the level of the mould. Thus, when the submerged entry nozzle depth is less than 130mm, this means that the submerged entry nozzle is less than 130mm from the mould level. The electromagnetic braking compensation current 30-50A is increased in order to reduce the flow rate of molten steel in the mold. Electromagnetic braking is a technique for controlling the flow rate of molten steel by using a magnetic field, and by increasing a compensation current, the effect of the electromagnetic field can be enhanced, thereby reducing the flow rate of molten steel. Thereby better controlling the temperature of molten steel and the crystallization process, improving the quality of casting blanks and reducing the crack tendency of the casting blanks. Meanwhile, the reduction of the flow rate is also beneficial to reducing the scouring and erosion of the copper wall of the crystallizer and prolonging the service life of the crystallizer.
Further, after reducing the flow rate of molten steel in the mold to a preset range, it further comprises: when the continuous casting machine just starts to run, when the eye-covering phenomenon is detected, the rod shaking is started, and the eye-covering is eliminated through vibration. By flushing the eye-covering product as soon as possible, the impact range is reduced. The eye-covering phenomenon can be judged by continuously increasing the opening amount of the stopper in the casting process and the opening amount of the stopper at the stable pulling speed. And whether the eye-covering phenomenon exists can also be judged by analyzing whether the chemical components of molten steel in the crystallizer are abnormal.
Step S103, when the casting process of the continuous casting machine detects that the quantity of the nozzle hole rod is increased, signals are sent to a refining main control device and a rolling mill main control device of the continuous casting machine; and responding to the signal, controlling the detection equipment to detect the surface quality of the steel coil corresponding to the heat, and feeding the data of the detected slag rolling phenomenon back to the terminal.
It should be noted that this step is mainly to operate on the emergency situation of slag rolling. When the sensor detects that the quantity of the nozzle eye rod is increased, signals are sent to a refining main control device of the continuous casting machine and a rolling mill main control device, and steel coils are detected. The detection can adopt image recognition to acquire the slag rolling characteristics so as to judge whether slag rolling occurs or not, and the problem feedback value is ended, so that staff can acquire problem information rapidly and process the problem information in time, and the product quality is improved.
Further, the method further comprises the steps of:
In the stage of crystallizer inspection, the end part of the spot inspection bar is controlled to move on the liquid slag layer so as to reduce slag coiling caused by the contact of the spot inspection bar head and molten steel.
In the continuous casting process, the slag layer in the crystallizer is an oxide film formed on the surface of molten steel, and plays a role in lubrication and isolation while protecting the molten steel from secondary oxidation. The purpose of the point inspection rod is to ensure the cleaning and normal working state of the interior of the crystallizer and to monitor the thickness and quality of the liquid slag layer. By allowing the end of the spot inspection rod to move on the slag layer, the chance of the rod head directly contacting with high-temperature molten steel can be reduced, thereby avoiding severe reaction caused by direct contact. Such reactions may lead to rapid oxidation or melting of the club head material, affecting the accuracy of the inspection. In addition, direct contact with the molten steel may cause tiny fragments or scale of the club head material to enter the molten steel, forming slag. Therefore, the end part of the control point detecting rod moves on the liquid slag layer to avoid the phenomenon of slag rolling.
Further, the method further comprises the steps of:
In the stage of expanding and pulling speed at the initial stage of casting, judging waste of the casting blank based on a wedge-shaped waste judging principle according to the shape and the size of the casting blank; determining a corresponding pouring length threshold based on the waste judgment data; and controlling the pouring length to finish the treatment of the cold steel and slag strips before reaching the threshold value of the pouring length.
In the continuous casting process, the shape and the size of the casting blank need to be controlled and judged. Wedge-shaped waste judgment refers to a method for judging waste of a casting blank according to whether the shape and the size of the casting blank meet the requirements. Specifically, whether the casting blank is qualified or not is judged according to the width and the thickness of the casting blank and the proportion relation of the width and the thickness of the casting blank. If the width and thickness of the casting blank are not satisfactory or their ratio exceeds a certain range, the casting blank is judged as unacceptable and is required to be processed or discarded.
In addition, the cold steel and slag strips are processed before the casting length is controlled to be 3.5m (wedge-shaped waste judgment) in the initial stage of the expansion and pulling speed, namely, the casting length is controlled to be within 3.5m after the continuous casting machine starts to cast, and the cold steel and slag strips are processed in the stage. Wherein, cold steel refers to a billet which is not completely solidified in the crystallizer, and slag bars are impurities and slag in the crystallizer. Thereby avoiding the untimely treatment of slag strips and influencing the quality of casting blanks and the normal operation of continuous casting machines.
Further, the method further comprises the steps of:
As shown in fig. 2, in a preset area taking a submerged nozzle of a crystallizer as a center, a long roller of a slag picking roller is adopted to pick liquid slag from outside to inside so as to cover all positions; in the region far away from the immersed nozzle in the crystallizer, picking liquid slag by using a right-angle slag picking rod; the state of the right-angle slag picking rod is obtained in real time, and when the right-angle slag picking rod vibrates, the maximum depth of slag picking operation is judged.
Specifically, as shown in fig. 2, in order to cover all positions, in a preset area (namely, an area 1, an area 2, an area 5 and an area 6) taking a submerged nozzle of a crystallizer as a center, a long roller of a slag picking roller is adopted to pick liquid slag from the area 1 and the area 2 towards the direction of the submerged nozzle, so that the position in the area is covered. And for the areas 3 and 4, the right-angle slag picking rod is adopted to pick slag, and because the liquid slag layer in the crystallizer is continuously supplemented into the gap between the blank shell and the copper plate of the crystallizer, the liquid slag layer plays a role in lubricating and isolating while protecting molten steel from secondary oxidation. When the slag picking rod goes deep downwards, once the slag picking rod is contacted with molten steel, the violent reaction generated by direct contact generates shaking, so that the state of the right-angle slag picking rod is acquired in real time by utilizing the vibration sensor, and the maximum depth of slag picking operation is judged when the right-angle slag picking rod vibrates. The tiny fragments or oxide skin of the slag picking stick caused by the follow-up operation are prevented from entering molten steel, and the product quality is improved.
In summary, the technical scheme provides a method for reducing slag rolling of a sheet billet continuous casting machine, which is used for controlling impurities from a source, optimizing a casting process, accurately controlling the liquid level of a crystallizer, and monitoring and feeding back quality information in real time, so as to comprehensively improve the quality of a casting blank, provide a higher-quality raw material for a rolling mill, reduce the risk of rolling breakage, ensure smooth delivery of products and improve the overall production efficiency.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (10)
1. A method of reducing slag in a thin slab caster, the method comprising:
Cleaning particles in the tundish by using a dust collector, controlling the flow of argon blown into the continuous casting machine, and deslagging, supplementing a covering agent and casting according to a preset strategy so as to reduce molten steel pollution;
Calculating a crystallizer liquid level parameter of the continuous casting machine through frequency and pull speed, and controlling the crystallizer liquid level to be in a preset fluctuation range; when the immersion depth of the crystallizer is smaller than a threshold value, controlling electromagnetic braking compensation current, and reducing the flow rate of molten steel in the crystallizer to a preset range;
When the continuous casting machine detects that the quantity of the nozzle hole rod is increased in the casting process, signals are sent to a refining main control device and a rolling mill main control device of the continuous casting machine; and responding to the signal, controlling the detection equipment to detect the surface quality of the steel coil of the corresponding heat, and feeding the data of the detected slag rolling phenomenon back to the terminal.
2. The method of claim 1, wherein the step of controlling the flow rate of argon blown into the continuous casting machine further comprises:
Before the continuous casting machine is started, argon is blown into a tundish of the continuous casting machine until the volume fraction of the oxidizing gas is reduced below a threshold value, so that the gas replacement efficiency in the tundish is improved.
3. The method of claim 2, wherein the step of controlling the flow rate of argon blown into the continuous casting machine further comprises:
and controlling the argon blowing flow of the ladle long nozzle of the continuous casting machine to a preset range so as to reduce the liquid level rising of an argon impact area.
4. The method of claim 3, wherein the steps of deslagging, replenishing the covering agent and casting according to a preset strategy comprise:
When the continuous casting machine is started and the second furnace is started, deslagging is carried out on the tundish, and a covering agent is added again;
Replacing a sealing ring of the long water gap every furnace, discharging slag once every preset number of furnace times, and prompting slag discharge if steel slag flowing into the tundish from the ladle is detected;
When the tonnage of the starting furnace tundish is larger than the preset weight, opening a stopper rod for casting;
and when the slag quantity ratio is detected to be larger than a preset percentage, reducing the slag quantity of the tundish until the slag quantity ratio is lower than the preset percentage.
5. The method according to claim 1, characterized in that said step of calculating the crystallizer level parameter of said continuous casting machine by frequency and pull rate comprises in particular:
for liquid level fluctuation of fixed frequency, calculating the position generating the liquid level fluctuation according to the frequency and the pulling speed, and increasing the preset secondary cooling intensity to avoid high-frequency liquid level fluctuation.
6. The method of claim 5, wherein said step of controlling said crystallizer liquid level to be within a predetermined fluctuation range further comprises:
and the immersed nozzle of the crystallizer is centered by laser, so that the drift of molten steel is avoided.
7. The method of claim 1, wherein after reducing the flow rate of molten steel in the mold to a predetermined range, further comprising:
When the continuous casting machine just starts to run, when the eye-covering phenomenon is detected, the rod shaking is started, and the eye-covering is eliminated through vibration.
8. The method of any one of claims 1-7, further comprising:
and in the stage of the crystallizer inspection, controlling the movement of the end part of the spot inspection bar on the liquid slag layer so as to reduce slag coiling caused by the contact of the head of the spot inspection bar with molten steel.
9. The method of claim 8, wherein the method further comprises:
In the stage of expanding and pulling speed at the initial stage of casting, judging waste of the casting blank based on a wedge-shaped waste judging principle according to the shape and the size of the casting blank;
determining a corresponding pouring length threshold based on the waste judgment data; and controlling the pouring length to finish the treatment of the cold steel and slag strips before the pouring length threshold value is reached.
10. The method of claim 9, wherein the method further comprises:
in a preset area taking the immersed nozzle of the crystallizer as the center, adopting a long roller of a slag picking roller to pick liquid slag from outside to inside so as to cover all positions;
In the region far away from the immersed nozzle in the crystallizer, picking liquid slag by using a right-angle slag picking rod; and acquiring the state of the right-angle slag picking rod in real time, and judging the maximum depth of slag picking operation when the right-angle slag picking rod vibrates.
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