Anti-blocking argon blowing stopper rod for improving nozzle nodulation and continuous casting and continuous casting gas supply method

Abstract

The invention discloses an anti-blocking argon blowing stopper rod for improving nozzle nodulation and a continuous casting and continuous casting gas supply method. The argon blowing stopper rod comprises a stopper rod body, a stopper rod head and a gas channel. The bottom of the stopper rod body is connected with the stopper rod head, and one end, far away from the stopper rod head, of the stopper rod body is provided with a gas connecting joint connected with a gas supply pipeline; the gas channel is arranged in the stopper rod body; a gas inlet at the upper end of the gas channel is connected with the gas connector, and a gas outlet at the lower end of the gas channel is arranged at the central hole at the bottom of the stopper head; and the gas channel adopts a Tesla valve structure. The gas channel has the characteristic of a Tesla valve, one-way flowing of fluid is achieved, the phenomenon that the channel is blocked due to backflow of molten steel caused by negative pressure near the stopper rod head is effectively prevented, meanwhile, the argon blowing mode is optimized, and the stability of gas entering a water gap is effectively guaranteed; and the inclusion nodulation state and the continuous casting state of the water gap bowl part and the inner wall are improved, and the molten steel quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of iron and steel metallurgy, and more specifically, to an anti-blocking argon-blowing stopper for improving nozzle nodulation and a gas supply method for continuous casting and continuous pouring. Background Art

[0002] Nozzle nodulation often occurs in the upper nozzle and the submerged nozzle during continuous casting, especially nodulation in the submerged nozzle is the most common. Nozzle nodulation not only affects the smooth progress of continuous casting pouring, reducing the pouring efficiency, but is also a major cause of billet quality problems.

[0003] When pouring aluminum-killed steel, the deoxidation products adhere to the inner wall of the nozzle, and the inlet and outlet of the nozzle are the main positions where inclusions adhere, especially the part below the slag line. In addition to iron, the nodulation substances are mainly Al2O3, and there are also MgO and MnO, etc. Due to the adhesion and deposition of nodulation substances such as Al2O3 on the inner wall of the nozzle, the inner cavity of the nozzle is reduced, the molten steel flow rate is unstable, resulting in uneven flow and violent fluctuations in the mold liquid level, causing quality problems on the surface of the billet. The molten steel flow will also carry the nodulation substances washed and peeled off into the liquid phase of the mold, forming inclusions with larger particles, and finally forming quality defects of the billet; especially during the pouring process in the later stage of continuous pouring, when the nodulation of the stopper is severe to a certain extent, it will cause the inability to continue pouring steel, and the pouring must be ended in advance, which will affect the continuity of pouring, reduce the number of continuous casting heats, affect the continuous casting efficiency, and increase the production cost.

[0004] In order to prevent nozzle nodulation, the existing process is to adopt the stopper argon-blowing method during continuous casting pouring to improve the nozzle pouring state. By opening an argon channel inside the stopper to blow argon with a certain pressure and flow rate into the molten steel, the argon channel is a straight through hole with a certain diameter opened along the axis of the stopper, and the channel diameter is reduced at the stopper head, that is, the argon outlet part, to realize blowing argon during the pouring process, prevent inclusions from nodulating at the inlet bowl and the inner wall of the nozzle during continuous casting pouring, and avoid nozzle blockage. In the argon-blowing stopper, the commonly used gas supply structure forms at present are divided into single-hole type, multi-hole type, and dispersed type argon-blowing stoppers, that is, one or more vent holes are opened on the stopper head, and these vent holes are connected to the argon channel in the stopper body.

[0005] CN202010732290.4 discloses a high-quality steel continuous casting argon-blowing stopper, an argon-blowing stopper system and an argon-blowing method. The gas channel in the argon-blowing stopper includes a main channel, a diffusion gas chamber and a slit-type channel. The main channel is arranged on the central axis of the stopper body. One end of the main channel is connected to the gas supply pipeline, and the other end of the main channel communicates with a plurality of slit-type channels through the diffusion gas chamber. The outlets of the plurality of slit-type channels are dispersedly arranged on the bottom surface of the stopper head. In this argon-blowing system, the displacement sensor for detecting the displacement of the stopper is connected to the flow control valve for controlling the argon gas flow through a PLC. This technology improves the size and distribution state of the argon gas bubbles entering the molten steel, and dynamically adjusts the argon gas flow in the stopper according to the actual casting process, effectively improving the inclusion nodulation state in the nozzle bowl and inner wall and the continuous casting state, and improving the quality of the molten steel.

[0006] CN202010875419.7 provides an argon-blowing stopper and a manufacturing method thereof, including: a through cavity is provided through the center position of the inner layer of the stopper head; one end of the through cavity communicates with the inner cavity, and the other end communicates with the argon gas flow channel; the stopper head is conical, and the formed argon gas flow channel is arc-shaped; the argon gas flow channel is annular and is arranged around the central axis of the rod body; or, the argon gas flow channel is in multiple groups and is spaced apart around the central axis of the rod body, and the channel is arranged at the inner layer of the stopper head, one end communicates with the through cavity, and the other end communicates with the argon gas flow channel. The stopper of this technology has the argon-blowing function and can effectively improve the resistance to molten steel erosion.

[0007] CN202210586388.2 discloses a continuous casting argon-blowing stopper and a preparation method and application thereof. The stopper head at the front end of the stopper is made of a mesoporous material; inside the stopper head, there are two or more spherical gas chambers arranged adjacent to each other in the vertical direction and connected to the tubular argon gas channel. The volume of each spherical gas chamber gradually decreases from top to bottom. The outer wall at the connection between the stopper body and the stopper head is distributed with an erosion-resistant layer along the circumferential direction. This stopper can completely eliminate the problem of concentrated argon blowing, ensure that the argon gas with stable flow is dispersed into the molten steel, form small and uniform bubbles, eliminate the influence of large bubbles on the liquid level fluctuation in the mold, and effectively remove the flocculent inclusions at the stopper head, improve the flow control accuracy, enhance the argon-blowing effect, and purify the quality of the molten steel.

[0008] Generally speaking, the existing argon blowing treatment methods play a good role in preventing nozzle caking and blockage, but there are also problems: (1) There are certain limitations in the design of the argon gas channel inside the stopper rod. The argon gas flow in the head area of the stopper rod is achieved by pre-burying high-temperature straight pipes. This method has a high resistance loss of gas flow. When used under a low gas source pressure, it is very easy to cause the phenomenon of molten steel backflow and steel pouring; (2) A negative pressure is formed in the main channel cavity inside the stopper rod under the action of the molten steel flow at the head of the stopper rod. Since the connection between the tail of the stopper rod and the argon blowing pipe is a high-temperature hard connection, when the argon gas pressure and flow rate are not appropriate, air is inhaled at this connection, resulting in secondary oxidation of the molten steel; (3) Some porous material permeable plugs are used in the head area of the stopper rod. Due to the high resistance loss of the pores, a relatively high operating pressure is required. When the gas source pressure is low, it is easy to be blocked and difficult to be unblocked again. And after being eroded by the molten steel for a long time, the rod head is easy to loosen and fall off; (4) The argon blowing flow rate during the existing casting process is constant, or the argon blowing flow rate is only adjusted after a set time period, so that the argon blowing flow rate does not exactly match the actual casting conditions. Summary of the Invention

[0009] Aiming at the defects existing in the prior art, the purpose of the present invention is to provide an anti-blocking argon blowing stopper rod for improving nozzle caking and a continuous casting and continuous pouring gas supply method. The gas channel for blowing argon into the stopper rod is improved. By utilizing the characteristics of the gas channel having a Tesla valve tube, the unidirectional flow of the fluid is realized, effectively preventing the phenomenon of channel blockage caused by the backflow of molten steel due to negative pressure near the head of the stopper rod. At the same time, the argon blowing method is optimized, effectively ensuring the stability of the gas entering the nozzle, improving the inclusion caking state of the nozzle bowl and inner wall and the continuous casting state, and improving the quality of molten steel.

[0010] To achieve the above purpose, the present invention adopts the following technical solutions:

[0011] The first aspect of the present invention provides an anti-blocking argon blowing stopper rod for improving nozzle caking, comprising a stopper rod body, a stopper rod head and a gas channel;

[0012] The bottom of the stopper rod body is connected to the stopper rod head, and a gas connection joint for connecting with a gas supply pipeline is provided at one end of the stopper rod body away from the stopper rod head;

[0013] The gas channel is arranged inside the stopper rod body; the gas inlet at the upper end of the gas channel is connected to the gas connection joint, and the gas outlet at the lower end thereof is arranged at the central opening position of the bottom of the stopper rod head; the gas channel adopts a Tesla valve structure.

[0014] Preferably, the Tesla valve structure includes a main flow channel and a plurality of branch flow channels opened on the main flow channel, and the plurality of branch flow channels are distributed alternately left and right in sequence from bottom to top.

[0015] Preferably, a separate closed loop is formed between each sub-runner and the main runner.

[0016] Preferably, the sub-runner includes a straight segment and an arc segment; one end of the straight segment is communicated with the main runner, and the other end is connected to the arc segment; the other end of the arc segment is communicated with the main runner.

[0017] Preferably, the included angle θ between the arc segment and the main runner is an obtuse angle.

[0018] Preferably, the gas pipeline is made of alumina ceramic material.

[0019] The second aspect of the present invention provides a continuous casting and continuous pouring gas supply method, which adopts the anti-blocking argon blowing stopper for improving nozzle nodulation as described in the first aspect of the present invention, and includes the following steps:

[0020] S1. When starting to pour from the ladle, when the molten steel flows into the tundish, turn on the argon gas source, supply argon gas into the gas passage of the argon blowing stopper, and control the argon gas flow rate to be 5.5 NL / min to 6.5 NL / min;

[0021] S2. During the pouring process, adjust the argon gas flow rate according to the weight of the molten steel in the tundish and the current casting speed;

[0022] S3. At the end of the casting campaign, when the weight of the molten steel in the tundish is less than 30 t, adjust the supplied argon gas flow rate until the pouring ends.

[0023] Preferably, in the step S1, the continuous supply time of the argon gas is 5 to 10 min.

[0024] Preferably, in the step S2:

[0025] When the weight of the molten steel in the tundish ≥ 30 t, adjust the argon gas flow rate according to the current casting speed;

[0026] When the casting speed > 1 m / min, adjust the argon gas flow rate to 4.5 to 6 NL / min;

[0027] When the casting speed ≤ 1 m / min, adjust the argon gas flow rate to 3 to 4.5 NL / min.

[0028] Preferably, in the step S3, the argon gas flow rate is 3 to 5 NL / min.

[0029] The beneficial effects of the present invention:

[0030] 1. The present invention improves the gas passage in the argon blowing stopper. A gas passage is arranged inside the stopper body, and this gas passage has a Tesla valve structure. It does not require internal mechanical movement, and only uses the spatial structure to promote the forward flow of gas, accelerating the gas through the physical structure and reducing the energy loss of the gas during transportation. During use, the gas resistance of the gas passage is small. Within the pressure range provided by the gas source, the maximum and minimum gas supply intensities required by the process can be met at a relatively low back pressure, preventing the serious fluctuation of the steel slag interface in the mold caused by excessive argon pressure, and effectively ensuring the stability of the gas flow inside the argon blowing stopper.

[0031] 2. The present invention improves the gas passage of the argon blowing stopper. The gas passage inside the stopper body has a Tesla valve structure, which allows the fluid to flow only in one direction, while having a very large resistance or even no flow in the other direction. This check valve characteristic prevents the problems of molten steel backflow and secondary oxidation of molten steel caused by too low argon pressure or negative pressure, and effectively improves the nodulation situation of the stopper head and the nozzle.

[0032] 3. The present invention designs the argon blowing method of the stopper during continuous casting. That is, during normal casting, according to the dynamic changes of the starting casting situation, the molten steel weight in the tundish, and the drawing speed, it adopts staged control, and adjusts the argon blowing flow rate in real time dynamically, ensuring that an appropriate gas carrying capacity per ton of steel is blown into the nozzle, effectively improving the nodulation state of inclusions in the nozzle bowl and inner wall and the continuous casting state, and improving the quality of molten steel.

[0033] 4. The anti-blocking argon blowing stopper for improving nozzle nodulation of the present invention has a simple structure, low processing cost, stable structure, and long service life. It optimizes the gas passage structure of the argon blowing of the stopper, ensures the stability of the gas entering the nozzle of the mold, reduces the backflow blockage of molten steel in the gas passage of the stopper head, gives full play to the role of argon bubbles in adsorbing and removing inclusions and improving nozzle nodulation, and dynamically adjusts the argon flow rate according to the actual casting process, making the blown argon volume adapt to the current casting situation, effectively improving the nodulation state of inclusions in the nozzle bowl and inner wall and the continuous casting state, and improving the quality of molten steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of the anti-blocking argon blowing stopper for improving nozzle nodulation of the present invention;

[0035] Figure 2 In the figure, on the left is a perspective view of the annular gap gas passage of the present invention; on the right is an enlarged view of the shunt passage;

[0036] In the figure, 1. Stopper body, 2. Stopper head; 3. Gas passage; 31. Main passage; 32. Shunt passage; 321. Straight section; 322. Arc section; 4. Gas connection joint; 5. Opening. DETAILED DESCRIPTION OF THE INVENTION

[0037] To better understand the above technical solution of the present invention, the technical solution of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0038] Combined with Figure 1 As shown, an anti-blocking argon-blowing stopper for improving nozzle nodulation provided by the present invention includes a stopper body 1, a stopper head 2, and a gas channel 3. The bottom of the stopper body 1 is connected to the stopper head 2, and a gas connection joint 4 connected to the gas supply pipeline is provided at one end of the stopper body 1 away from the stopper head 2, which facilitates the quick installation and disassembly of the gas supply pipeline. Combined with Figure 1 As shown, the gas channel 3 is arranged inside the stopper body 1; the gas inlet at the upper end of the gas channel 3 is connected to the gas connection joint 4, and the gas outlet at the lower end thereof is arranged at the position of the central opening 5 at the bottom of the stopper head 2; the gas channel 3 adopts a Tesla valve structure.

[0039] Combined with Figure 2 As shown, the Tesla valve structure includes a main flow channel 31 and a plurality of branch flow channels 32 opened on the main flow channel 31, and the plurality of branch flow channels 32 are distributed alternately left and right in sequence from bottom to top. Among them, a separate closed loop is formed between each branch flow channel 32 and the main flow channel 31, and the gas flowing through the branch flow channel 32 from the main flow channel 31 finally returns to the main flow channel 31 again.

[0040] Combined with Figure 2 As shown, the branch flow channel 32 includes a straight section 321 and an arc section 322; one end of the straight section 321 is communicated with the main flow channel 31, and the other end is connected to the connecting arc section 322; the other end of the arc section 322 is communicated with the main flow channel 31; among them, after the arc section 322 changes the direction of the gas, the gas flows back into the main flow channel 31 again.

[0041] Combined with Figure 2 As shown, the included angle θ between the arc section 322 and the main flow channel 31 is an obtuse angle, and such a setting can make the airflow flowing out of the arc section 322 produce a propulsion and acceleration effect on the airflow in the main flow channel 31.

[0042] In a specific embodiment, the gas pipeline is made of alumina ceramic material.

[0043] Combined with Figure 1As shown in the figure, the anti-blocking argon-blowing stopper rod for improving nozzle nodulation of the present invention has the advantages of anti-blocking, easy reconnection, and small resistance loss. The argon-blowing stopper rod makes full use of the physical characteristics of its gas channel 3 having a Tesla valve. The biggest feature of this Tesla valve is that it has no moving parts, and realizes the one-way flow of fluid only through the design of the gas flow channel. When flowing in the reverse direction, a very large resistance will appear. The principle is as follows: when the fluid flows in the reverse direction, the fluid will be divided into two streams by each partition, and one stream of fluid will be deflected by the flow channel and then collide with the main stream fluid, resulting in a large pressure loss. After passing through multiple partitions, the pressure loss gradually increases, resulting in a large pressure difference between the inlet and outlet, thus forming a resistance, so that only a very small amount of fluid can pass through during reverse flow; while this does not happen during forward flow, and at this time the fluid will flow out smoothly along the main flow channel 31. Therefore, it can effectively prevent the backflow of molten steel, work under a lower gas pressure, and is not easily blocked by the negative pressure backflow of the gas supply channel.

[0044] The present invention provides a continuous casting and continuous pouring gas supply method. By studying the relationship between the slag inclusion defect of hot-rolled coils and the continuous casting argon-blowing flow rate under different casting speed intervals, it is found that the generation of slag inclusion defects in hot-rolled coils shows a relatively obvious pattern with the continuous casting argon-blowing flow rate. Under the condition of a low casting speed section, a small argon-blowing flow rate is more likely to cause slag inclusion defects, while under the condition of a high casting speed section, a large argon-blowing flow rate is more likely to cause slag inclusion defects. Therefore, the above anti-blocking argon-blowing stopper rod for improving nozzle nodulation is adopted in the present invention, and after a large number of experimental scheme comparisons, an appropriate argon-blowing method is optimized, and the continuous casting argon-blowing flow rate is adjusted according to the actual pouring process, effectively ensuring the stability of the gas entering the nozzle, improving the nodulation state of inclusions in the nozzle bowl and inner wall and the continuous casting state, and improving the quality of molten steel.

[0045] The continuous casting and continuous pouring gas supply method of the present invention adopts the above anti-blocking argon-blowing stopper rod for improving nozzle nodulation, and adopts phased control according to the dynamic changes of the starting pouring situation, the molten steel weight in the tundish, and the casting speed during the continuous casting and continuous pouring process, and determines the argon gas flow rate range corresponding to each pouring stage of the slab continuous casting and continuous pouring process based on a large number of experimental studies and application time verifications.

[0046] The continuous casting and continuous pouring gas supply method of the present invention specifically includes the following steps:

[0047] S1. When starting to pour from the ladle, when the molten steel flows into the tundish, turn on the argon gas source, supply argon gas into the gas channel 3 of the argon-blowing stopper rod, and control the argon gas flow rate to be 5.5 NL / min to 6.5 NL / min. In a specific embodiment, the continuous supply time of argon gas is 5 to 10 minutes.

[0048] S2. During the pouring process, adjust the argon gas flow rate according to the molten steel weight in the tundish and the current casting speed, specifically as follows:

[0049] When the molten steel weight in the tundish ≥ 30t, adjust the argon gas flow according to the current casting speed; when the casting speed > 1m / min, adjust the argon gas flow to 4.5 - 6NL / min; when the casting speed ≤ 1m / min, adjust the argon gas flow to 3 - 4.5NL / min.

[0050] S3. At the end of the casting campaign, when the molten steel weight in the tundish is less than 30t (such as < 25t, etc.), adjust the supplied argon gas flow until the casting ends; in a specific embodiment, the argon gas flow is reduced to 3 - 5NL / min.

[0051] By using the above anti - clogging argon - blowing stopper rod for improving nozzle nodulation and the continuous casting and continuous pouring gas supply method, the continuous casting and continuous pouring process can be stabilized, the rod position curve of the argon - blowing stopper rod during the casting process is stable, and continuous pouring for more than 10 heats can be achieved; after the casting ends, there are no obvious nodules on the inner wall and the bowl of the nozzle, the used argon - blowing stopper rod is intact, and at the same time, the total oxygen content in the steel of the cast slab product is reduced to within 10ppm.

[0052] The following further introduces the anti - clogging argon - blowing stopper rod for improving nozzle nodulation and the continuous casting and continuous pouring gas supply method of the present invention in combination with specific examples;

[0053] Embodiment

[0054] Combined with Figure 1 As shown, the anti - clogging argon - blowing stopper rod for improving nozzle nodulation is adopted in this embodiment. The stopper rod body 1 is made of aluminum - carbon material, and the stopper rod head 2 is made of magnesia - carbon material. After drying and firing, an aluminum - carbon - magnesia - carbon composite integral stopper rod structure is produced.

[0055] Combined with Figure 1 As shown, at the other end of the stopper rod body 1 away from the stopper rod head 2, there is an outward - extending gas connection joint 4, which is convenient for the quick installation and disassembly of the gas supply pipeline.

[0056] Combined with Figure 1 、 Figure 2 As shown in

[0057] Combined with Figure 2As shown, the runner 32 includes a straight segment 321 and an arc segment 322; one end of the straight segment 321 is connected to the main runner 31, and the other end is connected to the connecting arc segment 322; the other end of the arc segment 322 is connected to the main runner 31; where the arc segment 322 can change the direction of the gas and then flow back into the main runner 31; the included angle θ between the arc segment 322 and the main runner 31 is an obtuse angle, θ = 130°.

[0058] In this embodiment, taking the pouring of a certain grade of calcium-treated aluminum-killed steel as an example, the tundish used: the baking temperature ≥ 1200 °C, the baking time is 90 - 180 min, the outer wall temperature of the nozzle ≥ 600 °C, and the continuous casting and continuous pouring gas supply method includes the following steps:

[0059] (1) When the ladle starts pouring and the molten steel flows into the tundish, turn on the argon gas source, supply argon gas into the gas passage 3 of the argon blowing plug rod, keep the supplied argon gas flow rate at 6 NL / min, and continuously introduce it for 8 min;

[0060] (2) When the weight of the molten steel in the tundish reaches 30 t, adjust the flow rate of the supplied argon gas to 5 NL / min according to the current casting speed of 1.2 m / min;

[0061] (3) At the end of the casting process of a casting sequence, when the weight of the molten steel in the tundish is less than 25 t, reduce the supplied argon gas flow rate to 4 NL / min until the casting ends.

[0062] The method of continuous casting and continuous pouring gas supply in this embodiment can make the continuous casting process stable, the plug rod position curve is stable during the casting process, and the increase value of the rod position curve per hour does not exceed 2 mm, and continuous pouring of more than 10 furnaces of this type of steel can be achieved. After casting, there is no obvious nodulation on the nozzle bowl and inner wall, and the used plug rod is intact; at the same time, the total oxygen content in the steel of the cast slab product is reduced to within 10 ppm.

[0063] Comparative example

[0064] In the existing continuous casting argon blowing plug rod, the gas supply channel is a straight through hole with a certain diameter opened along the axis of the plug rod. A high-temperature resistant straight pipe is buried in the head of the plug rod, and argon gas is introduced into the plug rod through the high-temperature resistant straight pipe during the casting process, so that the argon gas blows towards the nozzle. The flow rate of the argon gas blown in during the casting process is basically constant, or occasionally adjusted manually according to the degree of argon back pressure, mold liquid level fluctuation, etc.

[0065] The continuous casting stability of using the above argon blowing plug rod and argon blowing method is poor. There is a large fluctuation and tumbling phenomenon at the steel slag interface in the mold. The increase value of the rod position curve per hour exceeds 8 mm. In some casting sequences, due to serious nozzle nodulation, the argon blowing back pressure rises sharply, and it is necessary to manually increase the argon blowing amount to adapt. Moreover, the metallurgical quality of the product is not high, and the total oxygen content in the steel of the cast slab product is 15 - 20 ppm.

[0066] In summary, the anti-clogging argon-blowing stopper rod for improving nozzle nodulation according to the present invention has a simple structure, low processing cost, and long service life. At the same time, it combines the argon gas flow strategies blown in different casting stages, ensuring the stability of the continuous casting pouring state, giving full play to the role of the stopper rod blowing argon gas in improving nozzle nodulation and removing inclusions, effectively improving the inclusion nodulation state of the nozzle bowl and inner wall and the continuous casting pouring state, and improving the quality of molten steel.

[0067] It should be noted that those of ordinary skill in the art in this technical field should recognize that the above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. As long as it is within the scope of the spirit of the present invention, changes and modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. An anti-blocking argon-blowing stopper for improving nozzle nodulation, characterized in that, It includes a stopper body, a stopper head, and a gas channel; The bottom of the stopper body is connected to the stopper head, and a gas connection joint connected to the gas supply pipeline is provided at one end of the stopper body away from the stopper head; The gas channel is arranged inside the stopper body; the gas inlet at the upper end of the gas channel is connected to the gas connection joint, and the gas outlet at the lower end thereof is arranged at the central opening position of the bottom of the stopper head; the gas channel adopts a Tesla valve structure.

2. The anti-blocking argon-blowing stopper for improving nozzle nodulation according to claim 1, wherein, The Tesla valve structure includes a main flow channel and a plurality of branch flow channels opened on the main flow channel, and the plurality of branch flow channels are distributed alternately left and right in sequence from bottom to top.

3. The anti-blocking argon-blowing stopper rod for improving nozzle nodulation according to claim 2, characterized in that, Each branch flow channel forms an independent closed loop with the main flow channel.

4. The anti-blocking argon-blowing stopper for improving nozzle caking according to claim 3, characterized in that, The branch flow channel includes a straight section and an arc section; one end of the straight section is communicated with the main flow channel, and the other end is connected to the arc section; the other end of the arc section is communicated with the main flow channel.

5. The anti-blocking argon-blowing stopper for improving nozzle nodulation according to claim 4, characterized in that, The included angle θ between the arc section and the main flow channel is an obtuse angle.

6. The anti-blocking argon-blowing stopper for improving nozzle nodulation according to claim 4, wherein The gas pipeline is made of alumina ceramic material.

7. A continuous casting and continuous pouring gas supply method, characterized in that, Using the anti-blocking argon-blowing stopper for improving nozzle nodulation according to any one of claims 1 to 6, comprising the following steps: S1. When the ladle starts pouring and the molten steel flows into the tundish, turn on the argon gas source, supply argon gas into the gas channel of the argon-blowing stopper, and control the argon gas flow rate to be 5.5 NL / min to 6.5 NL / min; S2. During the pouring process, adjust the argon gas flow rate according to the weight of the molten steel in the tundish and the current casting speed; S3. At the end of the casting campaign, when the weight of the molten steel in the tundish is less than 30 t, adjust the supplied argon gas flow rate until the pouring ends.

8. The continuous casting and continuous pouring gas supply method according to claim 7, characterized in that, In step S1, the continuous supply time of the argon gas is 5 to 10 min.

9. The continuous casting and continuous pouring gas supply method according to claim 7, characterized in that, In step S2: When the weight of the molten steel in the tundish ≥ 30 t, adjust the argon gas flow rate according to the current casting speed; When the casting speed > 1 m / min, adjust the argon gas flow rate to 4.5 to 6 NL / ton of steel; When the casting speed ≤ 1 m / min, adjust the argon gas flow rate to 3 to 4.5 NL / ton of steel.

10. The continuous casting and continuous pouring gas supply method according to claim 7, characterized in that, In step S3, the argon gas flow rate is 3 to 5 NL / min.

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