A continuous casting apparatus and method for interlocking electromagnetic swirling flow and swirling flow plug rod control in an tundish

Abstract

This invention belongs to the field of continuous casting technology, and discloses a continuous casting device and method that combines electromagnetic vortex flow and vortex plug rod control in a tundish. Before the molten steel flows out of the tundish, it is provided with a rotational speed, allowing the molten steel in the nozzle to achieve a strong rotational effect under relatively low electromagnetic vortex intensity. Embedding the electromagnetic vortex device at the bottom of the tundish avoids occupying space on the continuous casting platform and facilitates smooth slag pushing. It increases the rotational effect of the molten steel in the nozzle and the crystallizer, lengthening the streamline of the molten steel in the crystallizer, which is beneficial for the flotation and removal of inclusions. The combined effect of the vortex blades at the bottom of the tundish and the electromagnetic vortex improves the flow field in the crystallizer, alleviates flow deviation problems, homogenizes the solidification temperature, optimizes the solidification structure of the continuously cast billet, improves the adaptability of the continuous casting machine to different continuous casting process parameters, and enhances the process stability and economic benefits of continuous casting.

Description

Technical Field

[0001] This invention relates to the field of continuous casting technology, and in particular to a continuous casting device and method for interlocking electromagnetic swirling flow and swirling flow plug rod control in an tundish. Background Technology

[0002] Continuous casting (LCS) technology, since its introduction in the mid-20th century, has become a revolutionary technology in the steel industry. By pouring, cooling, and cutting molten steel in a continuous casting machine, steel companies can directly obtain billets with high dimensional accuracy and surface quality, greatly improving production efficiency and product quality. With the continuous development of LCS technology, the production capacity of steel companies has also rapidly increased, greatly promoting the modernization of the steel industry. However, with the intensification of the global energy and resource crisis, steel companies are facing increasing competitive pressure. To enhance their market competitiveness, the quality of steel has become a key factor. In the steel production process, the cleanliness of molten steel directly affects the mechanical properties and surface quality of the finished steel. Reducing the content of impurity elements in steel, especially non-metallic inclusions, has become a key task for steel companies. Non-metallic inclusions not only affect the mechanical properties of steel, leading to a decrease in material strength, but may also cause cracks or surface defects during processing. Therefore, effectively controlling the quantity, shape, size, and distribution of inclusions has become a crucial task in the continuous casting process.

[0003] In modern steel production, the crystallizer plays a crucial role. It not only determines the cooling rate of the molten steel but also directly affects the surface quality and internal defects of the cast billet. The surface and internal defects of the continuously cast billet are closely related to the flow state of the molten steel within the crystallizer. Unstable molten steel flow can lead to a series of problems, thus affecting the quality of the continuously cast billet. The flow of molten steel within the crystallizer controls the rising and separation of inclusions and bubbles. If the flow pattern is unstable, inclusions and bubbles may not be effectively removed, forming internal defects in the steel. Furthermore, the flow of molten steel near the meniscus also affects the melting, spreading, and entrainment behavior of the protective slag. If the molten steel flow is unstable, the protective slag may not be evenly distributed, or even slag may be entrained into the molten steel, thus affecting the quality of the molten steel and the surface quality of the cast billet. Fluctuations in the crystallizer's liquid level are also a critical factor. These fluctuations can lead to problems such as shear slag entrainment or vortex slag entrainment, both of which can cause surface defects or a decline in internal quality of the cast billet.

[0004] Common flow control methods within the crystallizer include electromagnetic stirring, electromagnetic braking, mechanical rotor nozzle technology, and electromagnetic vortex nozzle technology. Mechanical rotor nozzle technology creates a vortex flow in the molten steel by placing a rotating blade inside the submerged entry nozzle. However, in actual production, the mechanical rotor is eroded by the high temperature and high speed of the molten steel, leading to damage and becoming a major source of large inclusions in the molten steel. Chinese patent application number 200510047290.6 discloses an electromagnetic vortex nozzle, and Chinese patent application number 201410254236.8 discloses an electromagnetic vortex continuous casting method. Electromagnetic vortex nozzle technology drives the molten steel to rotate using electromagnetic force, which helps improve the flow state of the molten steel within the crystallizer, especially effectively reducing uneven outflow at the nozzle outlet and increasing the equiaxed crystal ratio, thereby mitigating macroscopic segregation in the cast billet. Simultaneously, electromagnetic vortex nozzle technology can significantly improve the removal rate of inclusions within the crystallizer and avoid slag entrapment, thus improving the cleanliness of the continuously cast billet.

[0005] In the implementation of electromagnetic vortex nozzle technology, a common method to optimize the rotation efficiency of molten steel inside the nozzle is to increase the current of the electromagnetic vortex nozzle device, thereby generating a stronger magnetic field. However, such enhancement inevitably leads to an increase in the size of the electromagnetic vortex device, which in turn occupies more operating space in the continuous casting platform's working area.

[0006] Patent CN201610522997 discloses a vortex generator and a vortex continuous casting method. By combining a cylindrical vortex tundish with a traditional continuous casting tundish, the molten steel flowing into the mold is made to have a rotating flow. During continuous casting, different billet products have different casting process parameters, requiring different molten steel rotation speeds. The vortex effect provided by the device and method in this patent cannot be adjusted according to specific continuous casting process parameters, and its adaptability to continuous casting processes with multiple steel grades and multiple cross-sections is insufficient.

[0007] Patent CN202210584946 discloses a continuous casting tundish device and process method with swirling flow effect. It provides rotational speed to the molten steel by adding a shaped stopper rod and a swirling cavity. The rotating molten steel flows into the crystallizer through the nozzle outlet. However, setting spiral grooves on the inner wall of the submerged entry nozzle is detrimental to nozzle production. In the slab continuous casting process, the submerged entry nozzle needs to be replaced. Due to the shape design of the shaped stopper rod, it is impossible to close the stopper rod during nozzle replacement, which can easily lead to steel leakage accidents.

[0008] Patent CN202410560405 discloses a swirling casting system and method for continuous casting of round billets, which adjusts the flow field of molten steel in the crystallizer by using three nozzles with different outlet angles. The cross-section of the round billet crystallizer is circular, allowing for the use of a three-submersible nozzle arrangement. However, the flow of molten steel in a slab crystallizer cannot be adjusted by adding nozzles with different outlet angles. Although this patent can generate a swirling flow of molten steel within the crystallizer, its application is relatively limited and cannot be applied to slab continuous casting. Summary of the Invention

[0009] The purpose of this invention is to address the problems existing in the prior art under different continuous casting process conditions by designing a continuous casting device and method that combines electromagnetic swirling flow and swirling stopper rod control in the tundish. This provides a rotating tangential force to the molten steel in the submerged entry nozzle. The molten steel flowing through the swirling blades in the tundish will have a certain rotating tangential velocity, and at the same time, it will be subjected to the rotating electromagnetic force generated by the electromagnetic swirling flow device, which can increase the swirling velocity of the molten steel. This invention can improve the molten steel flow deviation in the mold, enhance the removal effect of inclusions in the mold, optimize the solidification structure of the billet, improve the quality of the continuously cast billet, and improve the process stability and economic benefits of continuous casting.

[0010] The technical solution of the present invention is as follows: A continuous casting device for electromagnetic swirling and swirling plug rod control in a tundish includes a swirling plug rod 1, a tundish 2, a tundish swirling blade 3, a tundish electromagnetic swirling device 4, a sliding nozzle 5, a submerged entry nozzle 6, and a crystallizer 7; without changing the internal cavity structure of the tundish, the tundish swirling blade 3 and the tundish electromagnetic swirling device 4 are installed inside the bottom of the tundish; the sliding nozzle 5 and the submerged entry nozzle 6 are connected, with one end connected to the tundish swirling blade 3 and the other end connected to the crystallizer 7; the tundish 2, the tundish outlet, the sliding nozzle 5, the submerged entry nozzle 6, and the crystallizer 7 together constitute an integral molten steel flow channel 8; the molten steel in the tundish 2 flows out of the tundish 2 through the tundish outlet with the tundish swirling blade 3, and flows into the crystallizer 7 sequentially through the sliding nozzle 5 and the submerged entry nozzle 6.

[0011] The tundish electromagnetic vortex device 4 is placed inside the bottom of the tundish 2 and is concentric with the outlet of the tundish 2; the tundish vortex blade 3 is located inside the outlet of the tundish 2; the outer diameter of the tundish vortex blade 3 is smaller than the inner diameter of the tundish electromagnetic vortex device 4.

[0012] The continuous casting speed is controlled by controlling the distance between the swirling plug rod 1 and the swirling blades 3 in the tundish; the molten steel flows from the tundish 2 through the gap between the swirling plug rod 1 and the swirling blades 3 into the submerged entry nozzle 6.

[0013] The shape and size of the end of the swirling plug rod 1 are exactly the same as the shape and size of the swirling blade 3 in the tundish, and the two are interference-fitted. When the swirling plug rod 1 reaches the lowest point, the swirling blade 3 in the tundish is embedded in the groove of the plug rod 1, and the continuous casting speed is 0m / s.

[0014] The number of intermediate tumbler swirl blades 3 is 1 to 15, and the angle between the intermediate tumbler swirl blades 3 and the vertical direction is greater than 20° and less than 75°.

[0015] When the casting speed is 0.2–0.6 m / min, the angle of the tundish swirl vanes 3 is 20°–45°, and the number is 3–6, so there is no need to turn on the tundish electromagnetic swirl device 4; when the casting speed is 0.6–1.0 m / min, the angle of the tundish swirl vanes 3 is 30°–60°, and the number is 4–8, so there is no need to turn on the tundish electromagnetic swirl device 4; when the casting speed is 1.0–1.4 m / min, the angle of the tundish swirl vanes 3 is 45°–60°, and the number is 4–12, and the input current of the tundish electromagnetic swirl device 4 is 200–400 A; when the casting speed is above 1.4 m / min, the angle of the tundish swirl vanes 3 is 45°–75°, and the number is 4–12, and the input current of the tundish electromagnetic swirl device 4 is above 400 A.

[0016] The tundish electromagnetic vortex device 4 mainly consists of an iron core 9 and a winding coil 10, with the winding coil 10 wound around the surface of each iron core 9; after the winding coil 10 is energized, a rotating magnetic field is formed inside the iron core 9; the rotating magnetic field acts on the molten steel flowing through the tundish electromagnetic vortex device 4, driving the molten steel to rotate under the action of the Lorentz force.

[0017] The tundish swirl vane 3 is located at the bottom of the tundish at the molten steel outlet, and its vertical height is 20–500 mm; the cross-sectional area of ​​the tundish swirl vane 3 is 5–1000 mm². 2 .

[0018] The thickness of the intermediate ladle electromagnetic vortex device 4 is 5-50 cm, and its volume is 35640-356400 cm³. 3 The electromagnetic vortex device 4 in the tundish is cooled by air, water, or oil.

[0019] A continuous casting method using a tundish electromagnetic swirling flow and swirling flow plug rod co-controlled continuous casting device includes the following steps:

[0020] Step 1: Obtain continuous casting process parameters, including steel grade, billet pulling speed, and billet cross-sectional dimensions;

[0021] Step 2: According to the continuous casting process parameters, pass a current of the corresponding intensity into the electromagnetic vortex device 4 in the tundish.

[0022] Step 3: Connect tundish 1 to ladle through a long nozzle, and the molten steel in ladle flows into tundish 2;

[0023] Step 4: Connect the immersion sprue 6 to the bottom of the intermediate tank 2, and open the sliding sprue 5;

[0024] Step 5: Lift the swirling plug 1. The molten steel in the tundish 2 passes through the tundish swirling blades 3, and then through the bottom outlet of the tundish and the working area of ​​the electromagnetic swirling device 4 in the tundish, and enters the sliding nozzle 5 and the submersible nozzle 6 in sequence.

[0025] Step 6: Under the combined control of the electromagnetic vortex device 4 and the vortex blades 3 in the tundish, the molten steel generates a tangential velocity in the submerged nozzle 6 and begins to rotate and flow.

[0026] Step 7: Molten steel with a rotational tangential velocity flows into the crystallizer 7 through the immersion nozzle 6, improving the flow field of molten steel in the crystallizer 7.

[0027] This tundish electromagnetic vortex and vortex plug rod combined control continuous casting device and method is of great significance for the smooth operation of the continuous casting process and the control of billet quality. Based on different billet cross-sectional dimensions, steel grades, casting speeds, and superheat, the rotation speed of the molten steel in the nozzle and the flow state of the molten steel in the crystallizer are adjusted by regulating the current intensity supplied to the electromagnetic vortex device. The advantage of the tundish electromagnetic vortex and vortex plug rod combined control continuous casting device compared to a single electromagnetic vortex device is that it can increase the vortex velocity limit of the molten steel in the nozzle, while not occupying the operating space of the continuous casting platform, which is conducive to the smooth and stable operation of slag pushing.

[0028] This tundish electromagnetic swirling and swirling plug-bar co-controlled continuous casting device and method can change the flow direction of molten steel through swirling blades, transforming vertical flow into rotational flow. The swirling velocity is further increased after passing through the electromagnetic swirling device embedded in the tundish. The rotating molten steel from the submerged entry nozzle flows into the crystallizer, providing rotational velocity to the molten steel inside the crystallizer, which helps to improve the flow deviation within the crystallizer and enhance the removal efficiency of inclusions.

[0029] The beneficial effects of this invention are as follows: It provides a rotational speed to the molten steel before it flows out of the tundish, allowing the molten steel inside the nozzle to achieve a strong rotational effect under relatively low electromagnetic vortex intensity. Embedding the electromagnetic vortex device at the bottom of the tundish avoids occupying space on the continuous casting platform, facilitating smooth slag pushing. It increases the rotational effect of the molten steel inside the nozzle and the crystallizer, lengthening the streamline of the molten steel in the crystallizer, which is beneficial for the flotation and removal of inclusions. The combined effect of the vortex blades at the bottom of the tundish and the electromagnetic vortex improves the flow field within the crystallizer, alleviates flow deviation problems, homogenizes the solidification temperature, optimizes the solidification structure of the continuously cast billet, enhances the adaptability of the continuous casting machine to different continuous casting process parameters, and improves the process stability and economic benefits of continuous casting. Attached Figure Description

[0030] Figure 1 A three-dimensional schematic diagram of the intermediate tundish outflow system controlled by electromagnetic vortex flow and vortex plug rod.

[0031] Figure 2 A longitudinal sectional view of the tundish outlet system controlled by electromagnetic vortex and vortex plug rod.

[0032] Figure 3 for Figure 2 The sectional view at point AA provided in the image;

[0033] Figure 4 for Figure 2 A partially enlarged view of the embedded position of the electromagnetic vortex device;

[0034] Figure 5 for Figure 3 A magnified view of the embedded position of the electromagnetic vortex device.

[0035] In the figure: 1-Swirl plug rod; 2-Tundish; 3-Tundish swirl blade; 4-Electromagnetic swirl device; 5-Sliding nozzle; 6-Immersion nozzle; 7-Crystallizer; 8-Steel liquid flow channel; 9-Iron core; 10-Winding coil. Detailed Implementation

[0036] A specific implementation of a continuous casting device and method for interlocking electromagnetic swirling flow and swirling flow plug rods in an tundish is as follows: Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown in the accompanying drawings and specific embodiments, the technical solution of the present invention will be described in detail below. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

[0037] like Figures 1-5 As shown, a continuous casting device for electromagnetic swirling and swirling plug rod control in a tundish includes a swirling plug rod 1, a tundish 2, tundish swirling blades 3, an electromagnetic swirling device 4, a sliding gate nozzle 5, an immersion nozzle 6, a crystallizer 7, and a molten steel flow channel 8. The swirling plug rod 1 is located inside the tundish 2 and is aligned with the bottom outlet of the tundish.

[0038] The tundish bottom outlet inner wall is provided with tundish swirl blades 3, and the tundish swirl blades 3 and tundish 2 are an integral structure; the size, shape and number of swirl blades determine the size, shape and number of grooves on the stopper head of the swirl stopper 1, which can achieve an interference fit; when the stopper reaches the lowest point, the tundish swirl blades are embedded in the grooves of the stopper, and the continuous casting speed is 0m / s.

[0039] The swirling plug 1 is located above the swirling blade 3 at the bottom of the tundish. The continuous casting speed is controlled by adjusting the distance between the swirling plug 1 and the swirling blade 3 in the tundish.

[0040] The electromagnetic vortex device 4 consists of an iron core 9 and a winding coil 10; it is embedded in the bottom of the tundish 2 and is concentric with the bottom outlet of the tundish 2; the tundish vortex blades 3 are located inside the electromagnetic vortex device 4.

[0041] The tundish 2 cavity, tundish swirl vanes 3, sliding gate nozzle 5, submerged nozzle 6, and crystallizer 7 together form the overall flow channel 8 for molten steel. The molten steel in the tundish 2 flows through the tundish swirl vanes 3, and the Lorentz force generated by the electromagnetic swirl device 4 increases its rotational tangential speed. It then passes through the sliding gate nozzle 5 and the submerged nozzle into the crystallizer for cooling and solidification.

[0042] A continuous casting system and method for tundish electromagnetic swirling and swirling plug rod control includes a swirling plug rod 1, a tundish 2, tundish swirling blades 3, an electromagnetic swirling device 4, a sliding gate nozzle 5, an immersion nozzle 6, a crystallizer 7, and a molten steel flow channel 8.

[0043] The swirl plug 1 is located above the swirl vane 3 at the bottom of the tundish; the tundish cavity 2, the tundish swirl vane 3, the sliding nozzle 5, the submerged nozzle 6, and the crystallizer 7 together form the overall flow channel 8 for molten steel. The molten steel in the tundish 2 flows through the tundish swirl vane 3, passes through the sliding nozzle 5 and the submerged nozzle 6, and enters the crystallizer 7 to cool and solidify.

[0044] The electromagnetic vortex device 4 is embedded in the bottom of the intermediate package 2 and is concentric with the bottom outlet of the intermediate package 2.

[0045] The tundish 2 controls the continuous casting speed by controlling the distance between the swirling plug rod 1 and the swirling blade 3 in the tundish.

[0046] Specifically, the cross-sectional shape of the swirl plug 1 can be circular, elliptical, rectangular, or a polygon with 3 to 20 sides.

[0047] The shape and number of grooves in the swirl plug 1 are affected by the swirl blades 3 in the tundish.

[0048] The shape and size of the swirling stopper rod 1 are exactly the same as those of the swirling blade 3 in the tundish, which can achieve an interference fit; when the stopper rod reaches the lowest point, the swirling blade in the tundish is embedded in the groove of the stopper rod, and the continuous casting speed is 0 m / s.

[0049] Specifically, the height L of the swirling plug rod 1 is 500-3000 mm, and the diameter D is 20-100 mm.

[0050] Specifically, the weight of the tundish 2 filled with molten steel is 4 to 400 tons.

[0051] Specifically, the shape of the intermediate swirl blade 3 is a fan blade or a triangular prism, and the cross-sectional shape of the swirl blade is a semi-circle, an arc, or a polygon, with the polygon having 2 to 20 sides.

[0052] The number of intermediate swirl blades 3 is 1 to 15, and the angle α between the swirl blades and the vertical direction is greater than 20° and less than 75°.

[0053] The tundish swirl vane 3 is located at the bottom of the tundish at the molten steel outlet, and the vertical height h of the tundish swirl vane 3 is... x The cross-sectional area s of the vortex blades in the tundish is 20–500 mm; the cross-sectional area s of the blades in the tundish is 5–1000 mm. 2 .

[0054] The outlet shape of the intermediate cask 2 is the same as the cross-sectional shape of the plug head of the swirling plug rod 1.

[0055] Specifically, the plug head of the swirl plug 1 is hemispherical, spherical, prism, or frustum-shaped.

[0056] The electromagnetic vortex device 4 consists of an iron core 9 and a winding coil 10. When the winding coil 10 is energized, it forms a rotating magnetic field inside the iron core 9.

[0057] Specifically, the electromagnetic vortex device 4 is horseshoe-shaped, semi-circular, circular, or parallelogram-shaped.

[0058] Specifically, the h of the electromagnetic vortex device 4 s Thickness ranges from 5 to 50 cm, and volume ranges from 35,640 to 356,400 cm³. 3 .

[0059] The rotating magnetic field acts on the molten steel flowing through the electromagnetic vortex device 4, driving the molten steel to rotate under the action of the Lorentz force.

[0060] The electromagnetic vortex device 4 has an energizing frequency of 5-60Hz and an energizing current I of 0-800A. When the current is 0A, the electromagnetic vortex device is not activated, and the molten steel is subjected to rotational speed by the vortex blades of the tundish alone.

[0061] The electromagnetic vortex device 4 is embedded in the bottom of the intermediate package 2, and is cooled by air, water or oil on the outside of the device.

[0062] The height h of the immersion inlet 6 is 500-2000mm, the inner diameter Φ1 is 10-100mm, and the outer diameter Φ2 is 80-200mm.

[0063] Specifically, the immersion inlet can be a straight-through inlet, a double-sided inlet, a four-sided inlet, or a multi-hole inlet.

[0064] Specifically, the multi-hole water inlet has 3 to 7 holes; the side-hole water outlets are centrally symmetrical.

[0065] Specifically, the crystallizer 7 can be a square billet crystallizer, a round billet crystallizer, a slab crystallizer, or a crystallizer for a continuous casting machine for irregularly shaped billets.

[0066] The electromagnetic swirling flow and swirling flow plug-controlled continuous casting method uses the aforementioned tundish swirling flow blades 3 and electromagnetic swirling flow device 4 to provide a rotational tangential velocity for the molten steel in the nozzle, and includes the following steps:

[0067] Step 1: Obtain continuous casting process parameters such as steel grade, billet pulling speed, and billet cross-sectional dimensions;

[0068] Step 2: According to the continuous casting process parameters, a current I of appropriate strength to the production requirements is introduced into the electromagnetic vortex device 4 in the tundish.

[0069] Step 3: Connect tundish 2 to ladle through a long nozzle. Molten steel flows from ladle into tundish 2 under the action of gravity.

[0070] Step 4: Connect the immersion gate 6 to the bottom of the intermediate tank and open the sliding gate 5.

[0071] Step 5: Raise the swirling plug rod 1, and the molten steel in the tundish 2 passes through the tundish swirling blades 3, and enters the submerged nozzle 6 through the bottom outlet of the tundish and the working area of ​​the electromagnetic swirling device 4.

[0072] Step Six: Under the combined control of electromagnetic swirling flow and tundish swirling blades, the molten steel generates tangential velocity in the submerged nozzle and begins to rotate and flow.

[0073] Step 7: Molten steel with a rotating tangential velocity flows into the crystallizer through an immersion nozzle, improving the flow field of molten steel in the crystallizer.

[0074] In the continuous casting production process, the dimensions of each position in the tundish outlet system controlled by the electromagnetic vortex flow and vortex plug rod can be set according to the needs of continuous casting. Specific embodiments are as follows:

[0075] Example 1

[0076] A continuous casting device for electromagnetic swirling and swirling stopper rod control in an tundish is disclosed. The swirling stopper rod 1 has a height L of 1200 mm, a diameter D of 100 mm, and an elliptical cross-sectional shape; the stopper head is hemispherical. The tundish 2 is filled with 100 t of molten steel. The casting speed is 0.5 m / min. The swirling blades 3 in the tundish are fan-shaped, with a rectangular cross-sectional shape and a cross-sectional area s of 500 mm². 2 The intermediate shroud has four swirl blades, with an angle α of 30° between the blades and the vertical direction. The vertical height h of the swirl blades is... x The diameter is 100mm. The electromagnetic vortex device is not powered. The submerged entry nozzle 6 is a straight-through nozzle with a height h of 750mm, an inner diameter Φ1 of 75mm, and an outer diameter Φ2 of 120mm. The crystallizer 7 is a round billet crystallizer. It is used for continuous casting of round billets. After using this invention, the same molten steel rotation intensity can be obtained as when a 200A current intensity is applied using conventional electromagnetic vortex nozzle technology.

[0077] Example 2

[0078] A continuous casting device for electromagnetic swirling and swirling stopper rod control in an tundish is disclosed. The swirling stopper rod 1 has a height L of 1300 mm, a diameter D of 110 mm, and a circular cross-sectional shape; the stopper head is hemispherical. The tundish 2, filled with molten steel, weighs 150 t. The casting speed is 0.8 m / min. The swirling blades 3 in the tundish are fan-shaped, with a rectangular cross-sectional shape and a cross-sectional area s of 500 mm². 2 The intermediate shroud has 6 swirl blades, with an angle α of 45° between the blades and the vertical direction, and a vertical height h of the blades. x The diameter is 90mm. The electromagnetic vortex device is not powered. The submerged nozzle 6 is a double-sided nozzle with centrally symmetrical outlets. The height h is 800mm, the inner diameter Φ1 is 80mm, and the outer diameter Φ2 is 130mm. The crystallizer 7 is a slab crystallizer. It is used for slab continuous casting. After using this invention, the same molten steel rotation intensity can be obtained as when a 350A current intensity is applied using conventional electromagnetic vortex nozzle technology.

[0079] Example 3

[0080] An electromagnetic swirling flow and swirling stopper rod co-controlled continuous casting system is disclosed. The swirling stopper rod 1 has a height L of 1500 mm, a diameter D of 120 mm, and an elliptical cross-sectional shape; the stopper head is hemispherical. The tundish 2 is filled with 200 t of molten steel. The casting speed is 1.4 m / min. The swirling blades 3 in the tundish are triangular prisms with a triangular cross-sectional shape and a cross-sectional area s of 500 mm². 2The intermediate shroud has 8 swirl blades, with an angle α of 60° between the blades and the vertical direction, and a vertical height h of the blades. x The thickness is 80mm. The electromagnetic vortex device 4 is circular in shape, with a thickness of h. s The sprue is 27cm long, operates at a frequency of 50Hz, and has a current I of 600A. It is water-cooled on the outside. The submersible nozzle 6 is a straight-through type with a height h of 900mm, an inner diameter Φ1 of 90mm, and an outer diameter Φ2 of 140mm. The crystallizer 7 is a square billet crystallizer, used for continuous casting of square billets.

[0081] Using this invention, the same molten steel rotation intensity as when using conventional electromagnetic vortex nozzle technology with a current intensity of 700A can be obtained. When the current supplied to the electromagnetic vortex device is 0A, the molten steel rotation intensity is increased by 20.86% compared to conventional electromagnetic vortex nozzle technology with a current intensity of 200A applied without changing the tundish outlet structure, after using this invention.

[0082] The solutions described in the embodiments are not intended to limit the scope of patent protection of this invention. All equivalent implementations or modifications that do not depart from the scope of this invention are included in the patent scope of this case.

Claims

1. A continuous casting device for electromagnetic swirling and swirling plug rod control in an tundish, characterized in that, The tundish electromagnetic swirling and swirling plug rod joint control continuous casting device includes a swirling plug rod (1), a tundish (2), a tundish swirling blade (3), a tundish electromagnetic swirling device (4), a sliding gate nozzle (5), an immersion nozzle (6), and a crystallizer (7). Without changing the internal cavity structure of the tundish, the tundish swirling blade (3) and the tundish electromagnetic swirling device (4) are installed inside the bottom of the tundish. The sliding gate nozzle (5) and the immersion nozzle (6) are connected, with one end connected to the tundish swirling blade (3) and the other end connected to the crystallizer (7). The tundish (2) and the tundish outlet are connected to the tundish outlet. The sliding nozzle (5), the submerged nozzle (6), and the crystallizer (7) together form an integral molten steel flow channel (8); the molten steel in the tundish (2) flows out of the tundish (2) through the tundish outlet with tundish swirl blades (3), and flows into the crystallizer (7) through the sliding nozzle (5) and the submerged nozzle (6) in sequence; the tundish electromagnetic swirl device (4) is placed inside the bottom of the tundish (2) and is concentric with the outlet of the tundish (2); the tundish swirl blades (3) are located inside the outlet of the tundish (2); the outer diameter of the tundish swirl blades (3) is smaller than the inner diameter of the tundish electromagnetic swirl device (4); The tundish swirl vane (3) is fan-shaped or triangular prism-shaped, and its cross-sectional shape is semi-circular, arc-shaped, or polygonal. The tundish swirl vane (3) is located at the bottom of the tundish at the molten steel outlet, and its vertical height is 20-500 mm. The cross-sectional area of ​​the tundish swirl vane (3) is 5-1000 mm². 2 ; The continuous casting speed is controlled by controlling the distance between the swirling plug rod (1) and the swirling blades (3) of the tundish; the molten steel flows from the tundish (2) into the submerged entry nozzle (6) through the gap between the swirling plug rod (1) and the swirling blades (3) of the tundish. The shape and size of the end of the swirling plug (1) are exactly the same as the shape and size of the swirling blade (3) in the tundish, and the two are interference fit; when the swirling plug (1) reaches the lowest point, the swirling blade (3) in the tundish is embedded in the groove of the plug (1), and the continuous casting speed is 0 m / s.

2. The tundish electromagnetic swirling and swirling plug rod co-controlled continuous casting device according to claim 1, characterized in that, The number of intermediate swirl blades (3) is 1 to 15, and the angle between the intermediate swirl blades (3) and the vertical direction is greater than 20° and less than 75°.

3. The tundish electromagnetic swirling and swirling plug rod co-controlled continuous casting device according to claim 2, characterized in that, When the billet casting speed is 0.2~0.6 m / min, the angle of the tundish swirl blades (3) is 20°~45°, and the number is 3~6, ​​so there is no need to turn on the tundish electromagnetic swirl device (4); when the casting speed is 0.6~1.0 m / min, the angle of the tundish swirl blades (3) is 30°~60°, and the number is 4~8, so there is no need to turn on the tundish electromagnetic swirl device (4); when the casting speed is 1.0~1.4 m / min, the angle of the tundish swirl blades (3) is 45°~60°, and the number is 4~12, and the input current of the tundish electromagnetic swirl device (4) is 200~400A; when the casting speed is above 1.4 m / min, the angle of the tundish swirl blades (3) is 45°~75°, and the number is 4~12, and the input current of the tundish electromagnetic swirl device (4) is above 400A.

4. The tundish electromagnetic swirling and swirling plug rod co-controlled continuous casting device according to claim 1, characterized in that, The tundish electromagnetic vortex device (4) is mainly composed of an iron core (9) and a winding coil (10). The surface of each iron core (9) is wound with a winding coil (10). After the winding coil (10) is energized, a rotating magnetic field is formed in the iron core (9). The rotating magnetic field acts on the molten steel flowing through the tundish electromagnetic vortex device (4) and drives the molten steel to rotate under the action of the Lorentz force.

5. The tundish electromagnetic swirling and swirling plug rod co-controlled continuous casting device according to claim 1, characterized in that, The thickness of the intermediate ladle electromagnetic vortex device (4) is 5~50cm, and the volume is 35640~356400cm³. 3 Air cooling, water cooling, or oil cooling are used on the outside of the electromagnetic vortex device (4) in the tundish.

6. A continuous casting method for a tundish electromagnetic swirling and swirling plug rod co-controlled continuous casting apparatus according to any one of claims 1-5, characterized in that, The steps include the following: Step 1: Obtain continuous casting process parameters, including steel grade, billet pulling speed, and billet cross-sectional dimensions; Step 2: According to the continuous casting process parameters, pass a current of the corresponding intensity into the electromagnetic vortex device (4) in the tundish; Step 3: Connect the tundish (2) to the ladle through the long nozzle, and the molten steel in the ladle flows into the tundish (2); Step 4: Connect the immersion nozzle (6) to the bottom of the intermediate package (2) and open the sliding nozzle (5); Step 5: Raise the swirling plug (1), and the molten steel in the tundish (2) passes through the tundish swirling blades (3), and then through the bottom outlet of the tundish and the action area of ​​the electromagnetic swirling device (4) of the tundish, and enters the sliding nozzle (5) and the submersible nozzle (6) in sequence; Step 6: Under the combined control of the electromagnetic vortex device (4) and the vortex blades (3) in the tundish, the molten steel generates a tangential velocity in the submerged nozzle (6) and begins to rotate and flow. Step 7: Molten steel with a rotational tangential velocity flows into the crystallizer (7) through the immersion nozzle (6) to improve the flow field of molten steel in the crystallizer (7).

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