Tundish electromagnetic rotational flow and rotational flow stopper joint control continuous casting device and method

Abstract

The invention belongs to the technical field of continuous casting, and discloses a tundish electromagnetic rotational flow and rotational flow stopper joint control continuous casting device and method. And a rotating speed is provided for the molten steel before the molten steel flows out of the tundish, so that the molten steel in the water gap obtains a relatively strong rotating effect under relatively small electromagnetic rotational flow intensity. The electromagnetic rotational flow device is embedded into the bottom of the tundish, so that the device is prevented from occupying the space of a continuous casting working platform, and the smooth operation of slag pushing work is facilitated. The rotating effect of the molten steel in the nozzle and the crystallizer is improved, the streamline of the molten steel in the crystallizer is increased, and floating removal of inclusions is facilitated. Through the combined action of the cyclone blades at the bottom of the tundish and the electromagnetic cyclone, the flow field in a crystallizer is improved, the bias flow problem is solved, the solidification temperature is homogenized, the solidification structure of a continuous casting billet is optimized, the adaptability of a continuous casting machine to different continuous casting process parameters is improved, and the process stability and economic benefits of continuous casting are improved.

Description

Technical Field

[0001] The invention relates to the technical field of continuous casting, and in particular to a tundish electromagnetic swirl and swirl plug rod joint control continuous casting device and method. Background Art

[0002] Since its advent in the mid-20th century, continuous casting (CC) technology has become a revolutionary technology in the steel industry. By pouring, condensing and cutting molten steel in a continuous casting machine, steel companies can directly obtain ingots with high dimensional accuracy and surface quality, greatly improving production efficiency and product quality. With the continuous development of continuous casting technology, the production capacity of steel companies has also been rapidly improved, greatly promoting the modernization of the steel industry. However, with the intensification of the global energy and resource crisis, the competitive pressure faced by steel companies has also continued to increase. In order to enhance the market competitiveness of enterprises, the quality of steel has become one of the key factors. 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, resulting in a decrease in material strength, but may also cause cracks or surface defects during processing. Therefore, how to effectively control the number, shape, size and distribution of inclusions has become a key task in the continuous casting process.

[0003] In modern steel production, the crystallizer plays a key role. The crystallizer not only determines the cooling rate of the molten steel, but also directly affects the surface quality of the ingot and the generation of internal defects. The surface and internal defects of the continuous casting ingot are closely related to the flow state of the molten steel in the crystallizer. If the flow of the molten steel in the crystallizer is unstable, it may cause a series of problems, which in turn affect the quality of the continuous casting ingot. The flow of molten steel in the crystallizer controls the floating 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. In addition, the flow of molten steel near the meniscus will also affect the melting, spreading and entrainment behavior of the mold slag. If the flow of molten steel is unstable, the mold slag may not be evenly distributed, and even the slag may be entrained in the molten steel, thus affecting the quality of the molten steel and the surface quality of the ingot. The fluctuation of the liquid level in the crystallizer is also a key factor. The fluctuation of the liquid level may cause problems such as shear slag or swirl slag, which may cause defects on the surface of the ingot or reduce the internal quality.

[0004] Common methods for controlling the flow in the crystallizer include electromagnetic stirring, electromagnetic braking, mechanical rotor nozzle technology, and electromagnetic swirl nozzle technology. The mechanical rotor nozzle technology places a rotating blade in the submerged nozzle to make the molten steel in the nozzle swirl. However, in actual production, the mechanical rotor is eroded by the high-temperature and high-speed molten steel and is damaged, becoming the main source of large-sized inclusions in the molten steel. The Chinese patent application number 200510047290.6 discloses an electromagnetic swirl nozzle, and the Chinese patent application number 201410254236.8 discloses an electromagnetic swirl continuous casting method. The electromagnetic swirl nozzle technology drives the molten steel to rotate through electromagnetic force, which helps to improve the flow state of the molten steel in the crystallizer, especially effectively reducing the uneven outflow phenomenon at the nozzle outlet, and can also increase the equiaxed crystal rate, thereby reducing the macro segregation of the ingot. At the same time, the electromagnetic swirl nozzle technology can significantly improve the removal rate of inclusions in the crystallizer, avoid the occurrence of slag roll problems, and thus improve the cleanliness of the continuous casting ingot.

[0005] In the implementation of electromagnetic swirl nozzle technology, in order to optimize the rotation efficiency of molten steel inside the nozzle, a common method is to increase the current of the electromagnetic swirl nozzle device to generate a stronger magnetic field. However, such enhancement measures will inevitably lead to an increase in the volume of the electromagnetic swirl device, thereby occupying more operating space in the operating area of ​​the continuous casting platform.

[0006] Patent CN201610522997 discloses a nozzle swirl generating device and a nozzle swirl continuous casting method. Through the use of a cylindrical swirl tundish and a traditional continuous casting tundish, the molten steel flowing into the crystallizer has a swirling flow. During the continuous casting process, the continuous casting process parameters of different ingot products are different, and the required molten steel rotation speed is different. The swirl effect provided by the device and method provided by this patent cannot be adjusted according to the specific continuous casting process parameters, and is not adaptable enough to the continuous casting process of multiple steel grades and multiple sections.

[0007] Patent CN202210584946 discloses a continuous casting tundish device and process method with swirl effect, which provides a rotation speed for the molten steel by adding a special-shaped stopper rod and a swirl cavity, and the rotating molten steel flows into the crystallizer through the nozzle outlet. Providing a spiral groove on the inner wall of the submerged nozzle is not conducive to nozzle production. In the process of slab continuous casting, the submerged nozzle is replaced. Due to the shape design of the special-shaped stopper rod, it is impossible to close the stopper rod when replacing the nozzle, which is prone to steel leakage accidents.

[0008] Patent CN202410560405 discloses a swirl casting system and method for round billet continuous casting production, which adjusts the flow field of molten steel in the crystallizer through three water inlets with different outflow angles. The cross-section of the round billet crystallizer is circular, and an arrangement of three immersed water inlets can be selected. However, the flow of molten steel in the slab crystallizer cannot be adjusted by adding water inlets with different outflow angles. Although this patent can make the molten steel produce a rotating flow in the crystallizer, the application scenario is relatively single and cannot be applied to slab continuous casting. Summary of the invention

[0009] The purpose of the present invention is to provide a rotational tangential force for the molten steel in the submerged water nozzle by designing a tundish electromagnetic swirl and swirl plug rod joint control continuous casting device and method under different continuous casting process conditions in view of the problems existing in the prior art. The molten steel flowing through the swirl blades of the tundish will have a certain rotational tangential velocity, and at the same time, it will be affected by the rotational electromagnetic force generated by the electromagnetic swirl device, which can increase the swirl velocity of the molten steel. The present invention can improve the deviation of molten steel in the crystallizer, enhance the removal effect of inclusions in the crystallizer, optimize the solidification structure of the ingot, improve the quality of the continuous casting ingot, and improve the process stability and economic benefits of continuous casting.

[0010] The technical scheme of the present invention is as follows: a tundish electromagnetic swirl and swirl plug rod joint control continuous casting device, comprising a swirl plug rod 1, a tundish 2, a tundish swirl blade 3, a tundish electromagnetic swirl device 4, a sliding water gate 5, an immersed water gate 6 and a crystallizer 7; on the basis of not changing the internal cavity structure of the tundish, the tundish swirl blade 3 and the tundish electromagnetic swirl device 4 are installed in the bottom of the tundish; the sliding water gate 5 and the immersed water gate 6 are connected, one end is connected to the tundish swirl blade 3, and the other end is connected to the crystallizer 7; the tundish 2, the tundish outlet, the sliding water gate 5, the immersed water gate 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 swirl blade 3, and flows into the crystallizer 7 through the sliding water gate 5 and the immersed water gate 6 in sequence.

[0011] The tundish electromagnetic cyclone device 4 is placed in the bottom of the tundish 2, concentric with the outlet of the tundish 2; the tundish cyclone blades 3 are located inside the outlet of the tundish 2; the outer diameter of the tundish cyclone blades 3 is smaller than the inner diameter of the tundish electromagnetic cyclone device 4.

[0012] The continuous casting billet drawing speed is controlled by controlling the distance between the swirl stopper rod 1 and the swirl blades 3 of the tundish; the molten steel flows from the tundish 2 into the submerged nozzle 6 through the gap between the swirl stopper rod 1 and the swirl blades 3 of the tundish.

[0013] The shape and size of the end of the swirl stopper rod 1 are exactly the same as those of the swirl blade 3 of the tundish, and the two are interference fit; when the swirl stopper rod 1 reaches the lowest point, the swirl blade 3 of the tundish is embedded in the groove of the stopper rod 1, and the continuous casting speed is 0m / s.

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

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

[0016] The intermediate ladle electromagnetic vortex device 4 is mainly composed of an iron core 9 and a winding coil 10, and a winding coil 10 is wound on the surface of each iron core 9; when 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 intermediate ladle electromagnetic vortex device 4, and drives the molten steel to rotate under the action of the Lorentz force.

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

[0018] The thickness of the intermediate package electromagnetic cyclone device 4 is 5 to 50 cm, and the volume is 35640 to 356400 cm 3 ; Air cooling, water cooling or oil cooling is adopted on the outside of the electromagnetic cyclone device 4 of the tundish.

[0019] A continuous casting method of a tundish electromagnetic swirl and swirl plug joint control continuous casting device, comprising the following steps:

[0020] Step 1, obtaining continuous casting process parameters, including steel type, billet drawing speed and billet cross-sectional dimensions;

[0021] Step 2: according to the continuous casting process parameter requirements, a current of corresponding intensity is introduced into the electromagnetic cyclone device 4 of the tundish;

[0022] Step 3, connecting the tundish 1 and the ladle through the long shroud, and the molten steel in the ladle flows into the tundish 2;

[0023] Step 4, connect the submerged nozzle 6 to the bottom of the tundish 2, and open the sliding nozzle 5;

[0024] Step 5, lifting the swirl plug rod 1, the molten steel in the tundish 2 passes through the tundish swirl blades 3, and passes through the tundish bottom outlet and the action area of ​​the tundish electromagnetic swirl device 4 to enter the sliding nozzle 5 and the submerged nozzle 6 in sequence;

[0025] Step 6: The molten steel generates a tangential velocity in the submerged nozzle 6 under the joint control of the tundish electromagnetic cyclone device 4 and the tundish cyclone blades 3, and starts to rotate and flow;

[0026] Step 7: The molten steel with a rotating tangential velocity flows into the crystallizer 7 through the submerged water inlet 6 to improve the flow field of the molten steel in the crystallizer 7.

[0027] The present tundish electromagnetic swirl and swirl plug rod joint control continuous casting device and method are of great significance to the smooth operation of the continuous casting process and the regulation of the quality of the ingot. According to different ingot cross-sectional dimensions, steel types, pulling speeds, superheat and other process parameters, the rotation speed of the molten steel in the water nozzle and the flow state of the molten steel in the crystallizer are adjusted by adjusting the intensity of the current passed into the electromagnetic swirl device. The advantage of the tundish electromagnetic swirl and swirl plug rod joint control continuous casting device over the single electromagnetic swirl device is that it can increase the swirl speed limit of the molten steel in the water nozzle, and at the same time, it no longer occupies the operating space of the continuous casting platform, which is conducive to the smooth and stable slag pushing work.

[0028] The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device and method can change the flow direction of molten steel through swirl blades, changing vertical flow to swirl flow, and the swirl speed is further increased after passing through the electromagnetic swirl device embedded in the tundish. The rotating molten steel from the submerged water inlet flows into the crystallizer, providing a rotation speed for the molten steel in the crystallizer, which is beneficial to improving the bias flow in the crystallizer and improving the removal effect of inclusions in the crystallizer.

[0029] The beneficial effects of the present invention are as follows: a rotation speed is provided to the molten steel before it flows out of the tundish, so that the molten steel in the water nozzle can obtain a stronger rotation effect under a smaller electromagnetic swirl intensity. The electromagnetic swirl device is embedded in the bottom of the tundish to avoid the device occupying the space of the continuous casting work platform, which is beneficial to the smooth slag pushing work. The rotation effect of the molten steel in the water nozzle and the crystallizer is increased, and the streamline of the molten steel in the crystallizer is increased, which is beneficial to the floating removal of inclusions. The combined action of the swirl blades at the bottom of the tundish and the electromagnetic swirl improves the flow field in the crystallizer, improves the deviation problem, makes the solidification temperature uniform, optimizes the solidification structure of the continuous casting billet, improves the adaptability of the continuous casting machine to different continuous casting process parameters, and improves the process stability and economic benefits of continuous casting. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a three-dimensional schematic diagram of the tundish outflow system controlled by electromagnetic swirl and swirl plug;

[0031] Figure 2 It is a longitudinal section view of the tundish outflow system controlled by electromagnetic swirl and swirl plug;

[0032] Figure 3 for Figure 2 The AA section view provided in;

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

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

[0035] In the figure: 1-swirl plug rod; 2-tundish; 3-tundish swirl blades; 4-electromagnetic swirl device; 5-sliding water inlet; 6-immersion water inlet; 7-crystallizer; 8-molten steel flow channel; 9-iron core; 10-winding coil. DETAILED DESCRIPTION

[0036] A specific implementation method of a tundish electromagnetic swirl and swirl plug rod joint control continuous casting device and method is as follows Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention rather than to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art fall within the scope defined by the claims attached to this application.

[0037] like Figures 1 to 5 As shown, a tundish electromagnetic swirl and swirl plug rod joint control continuous casting device comprises a swirl plug rod 1, a tundish 2, a tundish swirl blade 3, an electromagnetic swirl device 4, a sliding nozzle 5, an immersion nozzle 6, a crystallizer 7 and a molten steel flow channel 8. The swirl plug rod 1 is located inside the tundish 2 and is aligned with the bottom outlet of the tundish.

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

[0039] The swirl stopper rod 1 is located above the swirl blades 3 at the bottom of the tundish, and the continuous casting billet drawing speed is controlled by controlling the distance between the swirl stopper rod 1 and the swirl blades 3 of the tundish.

[0040] The electromagnetic vortex device 4 is composed 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, the tundish swirl blades 3, the sliding nozzle 5, the submerged nozzle 6, and the crystallizer 7 together constitute an overall flow channel 8 for the molten steel. The molten steel in the tundish 2 flows through the tundish swirl blades 3, and the tangential speed of the rotation is increased by the Lorentz force generated by the electromagnetic swirl device 4, and then passes through the sliding nozzle 5 and the submerged nozzle into the crystallizer to cool and solidify.

[0042] A tundish electromagnetic swirl and swirl plug rod joint control continuous casting system and method, comprising a swirl plug rod 1, a tundish 2, a tundish swirl blade 3, an electromagnetic swirl device 4, a sliding nozzle 5, an immersion nozzle 6, a crystallizer 7 and a molten steel flow channel 8;

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

[0044] The electromagnetic cyclone device 4 is embedded in the bottom of the tundish 2 and is concentric with the bottom outlet of the tundish 2 .

[0045] The tundish 2 controls the continuous casting billet drawing speed by controlling the distance between the swirl plug rod 1 and the swirl blades 3 of the tundish.

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

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

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

[0049] Specifically, the height L of the swirl 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 4-400t.

[0051] Specifically, the shape of the tundish swirl blade 3 is a fan blade or a triangular prism, and the cross-sectional shape of the swirl blade is a semicircle, an arc or a polygon, and the polygon has 2 to 20 sides.

[0052] The number of the tundish 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 blade 3 is located at the molten steel outlet at the bottom of the tundish, and the vertical height h of the tundish swirl blade 3 is x The cross-sectional area s of the tundish swirl blade 3 is 20 to 500 mm; the cross-sectional area s of the tundish swirl blade 3 is 5 to 1000 mm 2 .

[0054] The outlet shape of the tundish 2 is the same as the cross-sectional shape of the plug head of the swirl stopper rod 1 .

[0055] Specifically, the plug head of the swirl plug rod 1 is in the shape of a hemisphere, a sphere, a prism or a truncated pyramid.

[0056] The electromagnetic vortex device 4 is composed of an iron core 9 and a winding coil 10 . When the winding coil 10 is energized, a rotating magnetic field is formed in the iron core 9 .

[0057] Specifically, the electromagnetic vortex device 4 is in the shape of a horseshoe, a semicircle, a circle or a parallelogram.

[0058] Specifically, the h of the electromagnetic vortex device 4 is s Thickness is 5-50cm, volume is 35640-356400cm 3 .

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

[0060] The power-on frequency of the electromagnetic vortex device 4 is 5-60 Hz, and the power-on current I is 0-800 A. When the current is 0 A, the electromagnetic vortex device is not started, and the rotation speed is applied to the molten steel by relying on the single action of the vortex blades in the tundish.

[0061] The electromagnetic cyclone device 4 is embedded in the bottom of the tundish 2, and air cooling, water cooling or oil cooling is adopted on the outside of the device.

[0062] The submerged nozzle 6 has a height h of 500-2000 mm, an inner diameter Φ1 of 10-100 mm, and an outer diameter Φ2 of 80-200 mm.

[0063] Specifically, the submerged water inlet may be a straight-through water inlet, a double-side hole water inlet, a four-side hole water inlet or a multi-hole water inlet.

[0064] Specifically, the multi-hole water outlet is a 3-7-hole water outlet; the outlets of the side hole water outlet are centrally symmetrical.

[0065] Specifically, the crystallizer 7 may be a square billet crystallizer, a round billet crystallizer, a slab crystallizer or a profiled billet continuous casting machine crystallizer.

[0066] The electromagnetic swirl and swirl plug joint control continuous casting method adopts the tundish swirl blade 3 and the electromagnetic swirl device 4 to provide a rotating tangential velocity for the molten steel in the nozzle, and comprises the following steps:

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

[0068] Step 2: According to the continuous casting process parameter requirements, a current I adapted to the production intensity is introduced into the tundish electromagnetic cyclone device 4;

[0069] Step 3: connect the tundish 2 and the ladle through the long shroud, and the molten steel flows from the ladle into the tundish 2 under the action of gravity;

[0070] Step 4: Connect the submerged nozzle 6 to the bottom of the tundish and open the sliding nozzle 5.

[0071] Step 5: lift the swirl plug rod 1, and the molten steel in the tundish 2 passes through the tundish swirl blades 3, and passes through the tundish bottom outlet and the action area of ​​the electromagnetic swirl device 4 into the submerged water nozzle 6;

[0072] Step 6: The molten steel generates tangential velocity in the submerged nozzle under the joint control of the electromagnetic swirl and the tundish swirl blades, and starts to swirl;

[0073] Step 7: The molten steel with a rotating tangential velocity flows into the crystallizer through the submerged water inlet to improve the flow field of the molten steel in the crystallizer.

[0074] In the continuous casting production process, the position dimensions of the electromagnetic swirl and swirl plug rod joint control tundish outflow system can be set according to the continuous casting needs. The specific implementation example is as follows:

[0075] Example 1

[0076] A tundish electromagnetic swirl and swirl plug rod joint control continuous casting device, the swirl plug rod 1 has a height L of 1200mm, a diameter D of 100mm, and an elliptical cross-section shape; the plug head is hemispherical. The weight of the tundish 2 filled with molten steel is 100t. The pulling speed is 0.5m / min. The shape of the tundish swirl blade 3 is a fan blade, the cross-section shape of the swirl blade is rectangular, and the cross-sectional area s of the swirl blade 3 is 500mm 2 The number of tundish swirl blades 3 is 4, the angle α between the swirl blades and the vertical direction is 30°, and the vertical height h of the swirl blades is x The electromagnetic swirl device is not connected to electricity. The immersion nozzle 6 is a straight 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 applied to round billet continuous casting. After using the present invention, the same steel liquid rotation intensity as when the conventional electromagnetic swirl nozzle technology is used to apply a current intensity of 200A can be obtained.

[0077] Example 2

[0078] A tundish electromagnetic swirl and swirl plug rod joint control continuous casting device, the swirl plug rod 1 has a height L of 1300mm, a diameter D of 110mm, and a circular cross-section shape; the plug head shape is hemispherical. The weight of the tundish 2 filled with molten steel is 150t. The pulling speed is 0.8m / min. The shape of the tundish swirl blade 3 is a fan blade, the cross-section shape of the swirl blade is rectangular, and the cross-sectional area s of the swirl blade 3 is 500mm 2 The number of tundish swirl blades 3 is 6, the angle α between the swirl blades and the vertical direction is 45°, and the vertical height h of the swirl blades is x The electromagnetic swirl device is not connected to electricity. The immersion nozzle 6 is a double-side hole nozzle, the outlet of the side hole nozzle is centrally symmetrical, 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 applied to slab continuous casting. After using the present invention, the same molten steel rotation intensity as when the conventional electromagnetic swirl nozzle technology is applied with a current intensity of 350A can be obtained.

[0079] Example 3

[0080] An electromagnetic swirl and swirl plug rod joint control continuous casting system, the swirl plug rod 1 has a height L of 1500mm, a diameter D of 120mm, and an elliptical cross-section shape; the plug head shape is hemispherical. The weight of the tundish 2 filled with molten steel is 200t. The pulling speed is 1.4m / min. The shape of the tundish swirl blade 3 is a triangular prism, the cross-section shape of the swirl blade is a triangle, and the cross-sectional area s of the swirl blade 3 is 500mm 2The number of the tundish swirl blades 3 is 8, the angle α between the swirl blades and the vertical direction is 60°, and the vertical height h of the swirl blades is x The electromagnetic vortex device 4 is circular in shape and has a thickness of h s The diameter is 27 cm, the power-on frequency is 50 Hz, the power-on current I is 600 A, and the outer side is water-cooled. The immersion nozzle 6 is a straight-through nozzle with a height h of 900 mm, an inner diameter Φ1 of 90 mm, and an outer diameter Φ2 of 140 mm. The crystallizer 7 is a billet crystallizer. It is used for billet continuous casting.

[0081] After using the present invention, the same molten steel rotation intensity as that when using the conventional electromagnetic cyclone nozzle technology with a current intensity of 700A can be obtained. When the current passed into the electromagnetic cyclone device is 0A, after using the present invention, the molten steel rotation intensity is increased by 20.86% compared with the conventional electromagnetic cyclone nozzle technology with a current intensity of 200A and the same tundish outlet structure.

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

Claims

1. A tundish electromagnetic swirl and swirl plug rod joint control continuous casting device, characterized in that: The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device comprises a swirl plug rod (1), a tundish (2), a tundish swirl blade (3), a tundish electromagnetic swirl device (4), a sliding nozzle (5), an immersion nozzle (6) and a crystallizer (7); the tundish swirl blade (3) and the tundish electromagnetic swirl device (4) are installed in the bottom of the tundish without changing the internal cavity structure of the tundish; the sliding nozzle (5) and the immersion nozzle (6) are connected, one end of which is connected to the tundish swirl blade (3) and the other end is connected to the crystallizer (7); the tundish (2), the tundish outlet, the sliding nozzle (5), the immersion 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 swirl blade (3), and flows into the crystallizer (7) through the sliding nozzle (5) and the immersion nozzle (6) in sequence.

2. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 1, characterized in that: The tundish electromagnetic vortex device (4) is placed in the bottom of the tundish (2) and is concentric with the outlet of the tundish (2); the tundish vortex blades (3) are located inside the outlet of the tundish (2); and the outer diameter of the tundish vortex blades (3) is smaller than the inner diameter of the tundish electromagnetic vortex device (4).

3. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 1, characterized in that: The continuous casting billet drawing speed is controlled by controlling the distance between the swirl stopper rod (1) and the tundish swirl blades (3); the molten steel flows from the tundish (2) through the gap between the swirl stopper rod (1) and the tundish swirl blades (3) into the submerged water nozzle (6).

4. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 3, characterized in that: The shape and size of the end of the swirl stopper rod (1) are exactly the same as those of the tundish swirl blades (3), and the two are interference fit; when the swirl stopper rod (1) reaches the lowest point, the tundish swirl blades (3) are embedded in the grooves of the stopper rod (1), and the continuous casting speed is 0 m / s.

5. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 1, characterized in that: The number of the tundish swirl blades (3) is 1 to 15, and the angle between the tundish swirl blades (3) and the vertical direction is greater than 20° and less than 75°.

6. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 5, characterized in that: When the casting speed is 0.2-0.6 m / min, the angle of the tundish swirl blades (3) is 20°-45°, the number is 3-6, and the tundish electromagnetic swirl device (4) does not need to be turned on; when the casting speed is 0.6-1.0 m / min, the angle of the tundish swirl blades (3) is 30°-60°, the number is 4-8, and the tundish electromagnetic swirl device (4) does not need to be turned on; when the casting speed is 1.0-1.4 m / min, the angle of the tundish swirl blades (3) is 45°-60°, 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°, the number is 4-12, and the input current of the tundish electromagnetic swirl device (4) is above 400A.

7. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 1, characterized in that: The tundish electromagnetic swirling flow device (4) is mainly composed of an iron core (9) and a winding coil (10), and the surface of each iron core (9) is wound with a winding coil (10); when 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 swirling flow device (4), and drives the molten steel to rotate under the action of the Lorentz force.

8. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 7, characterized in that: The tundish swirl blade (3) is located at the molten steel outlet at the bottom of the tundish, and the vertical height of the tundish swirl blade (3) is 20 to 500 mm; the cross-sectional area of ​​the tundish swirl blade (3) is 5 to 1000 mm 2 .

9. The tundish electromagnetic swirl and swirl plug rod joint control continuous casting device according to claim 1, characterized in that: The thickness of the intermediate package electromagnetic cyclone device (4) is 5 to 50 cm, and the volume is 35640 to 356400 cm 3 ; Air cooling, water cooling or oil cooling is adopted on the outside of the electromagnetic cyclone device (4) of the tundish.

10. A continuous casting method according to any one of claims 1 to 9, wherein the continuous casting device is a tundish electromagnetic swirl and swirl plug joint control device, characterized in that: The steps include: Step 1, obtaining continuous casting process parameters, including steel type, billet drawing speed and billet cross-sectional dimensions; Step 2: according to the continuous casting process parameter requirements, a current of corresponding intensity is introduced into the electromagnetic cyclone device (4) of the tundish; Step 3, connecting the tundish (1) and the ladle through the long shroud, and the molten steel in the ladle flows into the tundish (2); Step 4: Connect the submerged nozzle (6) to the bottom of the tundish (2) and open the sliding nozzle (5); Step 5, lifting the swirl plug rod (1), the molten steel in the tundish (2) passes through the tundish swirl blades (3), and passes through the tundish bottom outlet and the action area of ​​the tundish electromagnetic swirl device (4) to enter the sliding water gate (5) and the immersed water gate (6) in sequence; Step 6: The molten steel generates a tangential velocity in the submerged nozzle (6) under the joint control of the tundish electromagnetic cyclone device (4) and the tundish cyclone blades (3), and starts to swirl; Step 7: The molten steel with a rotating tangential velocity flows into the crystallizer (7) through the submerged water inlet (6), thereby improving the flow field of the molten steel in the crystallizer (7).

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