Method for removing burrs of continuous casting billet

Abstract

The invention belongs to the field of steelmaking continuous casting, relates to a method for removing burrs from a continuous casting billet, and aims to solve the problem of poor effect of a traditional burr removing method, the pulling speed, the width of the casting billet and the length of a cutting area are comprehensively considered, and the walking speed of a cutting gun is dynamically adjusted, so that the amount and height of burrs generated on a cutting section are increased, and a cutter head of a burr machine can conveniently scrape the burrs. The specific adjusting rule is that when the continuous casting pulling speed is larger than or equal to 1.40 m / min, the walking speed of the cutting gun is reduced to 220 mm / min; when the continuous casting pulling speed is larger than or equal to 1.20 m / min and smaller than 1.40 m / min, the continuous casting pulling speed is reduced to 200 mm / min; and when the continuous casting pulling speed is smaller than 1.20 m / min, the continuous casting pulling speed is reduced to 180 mm / min. According to the method, the burr removing effect is remarkably improved, the quality loss is reduced, the production efficiency is improved, and the service life of equipment is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of continuous casting in steelmaking, and relates to a method for removing burrs from continuous casting billets. Background Art

[0002] In the field of continuous casting in steelmaking, the production of continuous casting billets is a complex and delicate process, which covers multiple key steps from molten steel smelting to the forming of continuous casting billets. Specifically, the production process of continuous casting billets usually includes the following main links:

[0003] First, the molten steel smelted in the converter is poured into the ladle, and after being treated by the refining process to remove impurities and harmful gases in the molten steel, the purity and quality of the molten steel are improved. Subsequently, the refined molten steel is transported to the continuous casting ladling platform for the next continuous casting operation.

[0004] On the continuous casting ladling platform, the molten steel flows from the ladle into the tundish and then is injected into the mold through the nozzle of the tundish. Under the combined action of the mold and the secondary cooling zone of continuous casting, the molten steel gradually cools and solidifies, and finally forms a continuous casting slab. In this process, the cooling effect of the mold and the temperature control of the secondary cooling zone of continuous casting are crucial for the quality of the continuous casting slab.

[0005] When the continuous casting slab is pulled out from the secondary cooling zone of continuous casting, it enters the cutting area. Here, the cutting gun cuts the continuous casting slab to make it reach the planned size. However, during the cutting process, steel slag and burrs often occur at the lower part of the cutting section of the continuous casting billet. If these burrs are not removed in time, they will have an adverse impact on the subsequent rolling process, and even lead to quality defects such as scarring on the hot coil.

[0006] The traditional method for removing burrs mainly relies on the scraping operation of the cutter head of the burring machine. However, in the actual production process, this method often faces the problem of poor burr removal effect. Specifically, when the burrs are less and shallower, the cutter head of the burring machine is prone to slipping during the scraping process, and it cannot apply enough scraping force to the burrs, resulting in the burrs not being effectively removed.

[0007] In order to improve the burr removal effect, continuous casting workers have tried measures such as adjusting the flame size of the cutting gun and frequently replacing the cutter head of the burring machine. However, these measures have not fundamentally solved the problem, and the burr removal effect is still very poor. Continuous casting workers have not found the real reason why the burrs cannot be removed and have not mastered effective improvement techniques, resulting in a large number of scarring defects on the hot coil after rolling the continuous casting billet, bringing serious quality losses to production.

[0008] In summary, the existing methods for removing burrs from continuous casting billets have problems such as poor burr removal effect and large quality losses, and there is an urgent need for a new method to improve the burr removal effect and the production quality of continuous casting billets. Summary of the Invention

[0009] In view of this, the purpose of the present invention is to provide a method for removing burrs from continuous casting billets, so as to solve the existing problems.

[0010] To achieve the above object, the present invention provides the following technical solution: A method for removing burrs from continuous casting billets, comprising the following steps:

[0011] S1: Pour the molten steel into the ladle after being smelted in the converter, and transport it to the continuous casting pouring platform after refining treatment;

[0012] S2: The molten steel flows from the ladle into the tundish and is injected into the mold through the tundish nozzle, and is cooled into a continuous casting slab in the mold and the secondary cooling zone of the continuous casting;

[0013] S3: After pulling the continuous casting slab out of the secondary cooling zone of the continuous casting, cut it into continuous casting billets of the planned size in the cutting area through a cutting gun;

[0014] S4: During the cutting process, dynamically adjust the walking speed of the cutting gun according to the continuous casting drawing speed, so as to increase the amount and height of burrs generated on the cutting section;

[0015] S5: Scrape the burrs on the cutting section of the continuous casting billet through the cutter head of the burr machine;

[0016] Among them, the adjustment rule of the walking speed of the cutting gun in step S4 is:

[0017] When the continuous casting drawing speed ≥ 1.40 m / min, the walking speed of the cutting gun is reduced to 220 mm / min;

[0018] When 1.20 m / min ≤ continuous casting drawing speed < 1.40 m / min, the walking speed of the cutting gun is reduced to 200 mm / min;

[0019] When the continuous casting drawing speed < 1.20 m / min, the walking speed of the cutting gun is reduced to 180 mm / min.

[0020] Optionally, the initial set value of the walking speed of the cutting gun in step S4 is 350 mm / min, which can achieve the purpose of cutting off the casting billet, but the burrs are less and shallower, and are easy to slide off during scraping.

[0021] Optionally, the adjustment of the walking speed of the cutting gun in step S3 needs to be combined with the width of the casting billet and the length of the cutting area to ensure that the casting billet is completely cut off.

[0022] Optionally, the increase in the amount of burrs in step S4 is achieved by reducing the walking speed of the cutting gun, so that it is not easy to slide off when the cutter head of the burr machine scrapes, introducing new thinking in the burr removal work.

[0023] Optionally, the operation of scraping burrs by the cutter head of the burr machine in step S5 is completed in the billet discharging area.

[0024] Optionally, the method is applicable to the continuous casting production process with a casting speed range of ≤ 1.60 m / min.

[0025] Optionally, the continuous casting billet is a slab, and the burr removal effect after cutting is achieved by a burr height ≥ 2 mm.

[0026] The beneficial effects of the present invention are as follows:

[0027] 1) The burr removal effect is significantly improved: By comprehensively considering the casting speed, the width of the casting billet, and the length of the cutting area, and dynamically adjusting the walking speed of the cutting gun, the amount and height of the burrs generated on the cutting section of the continuous casting billet are increased, so that the burrs are not easily slipped off when being scraped by the cutter head of the burr machine, and the burr removal effect is significantly improved.

[0028] 2) Reduce quality loss: The traditional burr removal method has poor effect, resulting in a large number of scar defects on the hot coils after rolling of the continuous casting billets, bringing serious quality losses to the production. The method of the present invention effectively solves the burr removal problem, reduces the quality defects caused by burrs, and thus reduces the quality loss.

[0029] 3) Improve production efficiency: Although adjusting the walking speed of the cutting gun may affect the cutting speed to a certain extent, by precisely controlling the walking speed, while ensuring the burr removal effect, the impact on production efficiency can be minimized. In addition, due to the improvement of the burr removal effect, the production interruptions and rework caused by burrs are reduced, thereby indirectly improving the production efficiency.

[0030] 4) Reduce costs and alleviate the labor intensity of workers: Frequent replacement of the cutter head of the burr machine not only increases the production cost but also increases the workload of workers. The method of the present invention reduces the replacement frequency of the cutter head by improving the burr removal effect, and also alleviates the labor intensity of workers.

[0031] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following specification. Detailed implementation manners

[0032] The following specific examples illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0033] Specific implementation method of a method for removing burrs from continuous casting billets

[0034] 1. Preparation stage:

[0035] Ensure the normal operation of the equipment in the continuous casting production line, including the converter, ladle, tundish, mold, secondary cooling zone of continuous casting, cutting gun, burr machine, etc.

[0036] Carry out converter smelting on the molten steel. After the smelting is completed, pour the molten steel into the ladle and carry out refining treatment to remove impurities and harmful gases and improve the purity of the molten steel.

[0037] The refined molten steel is transported to the continuous casting pouring platform for continuous casting operation.

[0038] 2. Continuous casting process:

[0039] The molten steel flows from the ladle into the tundish and then is injected into the mold through the tundish nozzle.

[0040] Under the combined action of the mold and the secondary cooling zone of continuous casting, the molten steel gradually cools and solidifies to form a continuous casting slab.

[0041] 3. Cutting process:

[0042] Pull the continuous casting slab out of the secondary cooling zone of continuous casting and enter the cutting area.

[0043] Dynamically adjust the walking speed of the cutting gun according to the continuous casting drawing speed:

[0044] When the continuous casting drawing speed ≥ 1.40 m / min, the walking speed of the cutting gun is reduced to 220 mm / min.

[0045] When 1.20 m / min ≤ continuous casting drawing speed < 1.40 m / min, the walking speed of the cutting gun is reduced to 200 mm / min.

[0046] When the continuous casting drawing speed < 1.20 m / min, the walking speed of the cutting gun is reduced to 180 mm / min.

[0047] During the cutting process, the walking speed of the cutting gun can be appropriately adjusted according to the width of the casting blank and the length of the cutting area to ensure that the casting blank is completely cut off.

[0048] 4. Burr removal process:

[0049] Transport the cut continuous casting billet to the billet discharging area.

[0050] Use the cutter head of the burr machine to scrape off the burrs on the cutting section of the continuous casting billet.

[0051] The operation of scraping off burrs with the cutter head of the burr machine needs to be completed in the billet discharging area.

[0052] 5. Quality control:

[0053] The burr removal effect after cutting is achieved by a burr height ≥ 2 mm to ensure that the burrs are effectively removed.

[0054] Regularly check the quality of the continuous casting billet to ensure that the burr removal effect meets the production requirements.

[0055] Example 1

[0056] The method of the present invention is implemented on a slab continuous caster in a certain steel plant. The continuous casting speed is 1.50 m / min. According to the method of the present invention, the walking speed of the cutting gun is reduced from the initial 350 mm / min to 220 mm / min. During the cutting process, the walking speed of the cutting gun is appropriately adjusted in combination with the width of the casting billet and the length of the cutting area to ensure that the casting billet is completely cut off. After cutting is completed, the continuous casting billet is transported to the billet discharging area, and a burr machine cutter head is used to scrape off the burrs on the cutting section. Through actual production verification, the burr removal effect has been significantly improved, and there are no quality defects such as scabbing in the hot coils after rolling the continuous casting billets.

[0057] Example 2

[0058] The method of the present invention is simultaneously implemented on two slab continuous casters in another steel plant. The casting speed of one continuous caster is 1.30 m / min, and the walking speed of the cutting gun is reduced from 350 mm / min to 200 mm / min; the casting speed of the other continuous caster is 1.10 m / min, and the walking speed of the cutting gun is reduced from 350 mm / min to 180 mm / min. During the cutting process, the walking speed of the cutting gun is also appropriately adjusted in combination with the width of the casting billet and the length of the cutting area. After cutting is completed, a burr machine cutter head is used to scrape off the burrs in the billet discharging area. After a period of production practice, it is found that the burr removal effects of the two continuous casters have been significantly improved, the quality of the hot coils has been significantly improved, and the quality defects and production interruptions caused by burrs have been reduced.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not restrictive. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the present technical solution, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A method for removing burrs from continuous casting billets, characterized in that, It includes the following steps: S1: Pour the molten steel into a ladle after converter smelting, and transport it to the continuous casting pouring platform after refining treatment; S2: The molten steel flows from the ladle into the tundish, and is injected into the mold through the tundish nozzle, and is cooled into a continuous casting slab in the mold and the secondary cooling zone of the continuous casting; S3: After pulling out the continuous casting slab from the secondary cooling zone of the continuous casting, cut it into continuous casting billets of planned size by a cutting gun in the cutting area; S4: During the cutting process, dynamically adjust the walking speed of the cutting gun according to the continuous casting drawing speed, so that the burr amount and height generated on the cutting section increase; S5: Scrape the burrs on the cutting section of the continuous casting billet by the cutter head of the burring machine; Among them, the adjustment rule of the walking speed of the cutting gun in step S4 is: When the continuous casting drawing speed ≥ 1.40 m / min, the walking speed of the cutting gun is reduced to 220 mm / min; When 1.20 m / min ≤ continuous casting drawing speed < 1.40 m / min, the walking speed of the cutting gun is reduced to 200 mm / min; When the continuous casting drawing speed < 1.20 m / min, the walking speed of the cutting gun is reduced to 180 mm / min.

2. The method for removing burrs from continuous casting billets according to claim 1, characterized in that: The initial set value of the walking speed of the cutting gun in step S4 is 350 mm / min, which can achieve the purpose of cutting off the casting billet, but the burrs are less and shallower, and are easy to slide off during scraping.

3. A method for removing burrs from continuous casting billets according to claim 1, characterized in that: The adjustment of the walking speed of the cutting gun in step S3 needs to be combined with the width of the casting billet and the length of the cutting area to ensure that the casting billet is completely cut off.

4. A method for removing burrs from continuous casting billets according to claim 1, characterized in that: The increase in the burr amount in step S4 is achieved by reducing the walking speed of the cutting gun, so that it is not easy to slide off when scraped by the cutter head of the burring machine, introducing new ideas in the burr removal work.

5. A method for removing burrs from a continuous casting billet according to claim 1, characterized in that: The operation of scraping the burrs by the cutter head of the burring machine in step S5 is completed in the billet discharging area.

6. A method for removing burrs from a continuous casting billet according to claim 1, characterized in that: The method is applicable to the continuous casting production process with a drawing speed range of ≤ 1.60 m / min.

7. A method for removing burrs from continuous casting billets according to claim 1, characterized in that: The continuous casting billet is a slab, and the burr removal effect after cutting is achieved by the burr height ≥ 2 mm.