A tundish pouring system

Abstract

The present invention discloses a tundish pouring system, which relates to the technical field of metallurgical equipment. It comprises: a tundish, a nozzle bag and a center pouring pipe, wherein the first end of the center pouring pipe is connected to the tundish; a protective assembly, wherein the protective assembly is arranged between the tundish and the nozzle bag, and a sealed protective cavity is formed between the tundish, the nozzle bag and the protective assembly, wherein the center pouring pipe is located in the protective cavity; and a first air inlet pipe, wherein the first air inlet pipe is connected to the protective cavity. The present invention protects the center pouring pipe in the protective cavity through the protective cavity formed between the protective assembly, the tundish and the nozzle bag, and constantly injects protective gas into the protective cavity through the first air inlet pipe, so that the center pouring pipe is always protected by the protective gas. When the connection between the center pouring pipe, the tundish and the nozzle bag is not tightly sealed, the molten steel in the center pouring pipe will not be oxidized, thereby reducing the adverse effects on the production of wide ultra-thin nanocrystalline strips.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical equipment, in particular to a tundish pouring system. Background Art

[0002] In nanocrystalline strip production, master alloy steel is typically smelted in an induction furnace. Various tundishes are then used to calm the steel and slow the production process. Ultra-thin nanocrystalline strip is then produced using a flat-surface strip casting process. Due to the unique characteristics of ultra-thin strip production, the master alloy steel must be highly purified. During the continuous nanocrystalline strip production process, steel is typically supplied to the nozzle ladle via bottom pouring from the tundish to achieve continuous production. Molten steel first enters the center pouring pipe from the bottom of the tundish, then flows from the bottom of the center pouring pipe into the nozzle ladle. Finally, it is ejected from the nozzle slit at the bottom of the nozzle ladle onto the high-speed rotating mold to form the ultra-thin strip. During the bottom pouring process, the tundish bottom pouring port and the center pouring pipe's upper gate, as well as the nozzle ladle's upper gate and the center pouring pipe's lower gate, require tight sealing. If this space is not properly sealed, exposure of the injected stream to the atmosphere can lead to secondary oxidation of the molten steel. At the same time, the exposure of the center pouring pipe to the atmosphere causes a significant temperature drop, leading to the precipitation of high-melting-point inclusions. The formation of new oxides and the increase in inclusions deteriorate the purity of the molten steel. The precipitation and accumulation of inclusions at the nozzle seam can severely affect the surface quality of the strip, causing scratches, splitting, and even nozzle blockage, leading to the termination of the spout. Therefore, protecting the injection flow in the center pouring pipe and reducing the N and O gas content and the precipitation of high-melting-point impurities during the bottom pouring process have become the main limitations on further improving the continuous production of wide, ultra-thin nanocrystalline strip. Summary of the Invention

[0003] The object of the present invention is to provide a tundish pouring system to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a tundish pouring system, comprising: a tundish, the tundish being used to receive molten steel; a nozzle bag, the nozzle bag being used to receive molten steel from the tundish; a center pouring pipe, the first end of the center pouring pipe being connected to the tundish, the second end of the center pouring pipe being connected to the nozzle bag, and the molten steel in the tundish can be transported to the nozzle bag through the center pouring pipe; a protective assembly, the protective assembly being arranged between the tundish and the nozzle bag, and a closed protective cavity being formed between the tundish, the nozzle bag and the protective assembly, and the center pouring pipe being located in the protective cavity; a first air inlet pipe, the first air inlet pipe being connected to the protective cavity, and the first air inlet pipe being used to transport protective gas to the protective cavity.

[0005] Preferably, the present technical solution further includes a second air inlet pipe and an air outlet pipe, wherein the second air inlet pipe and the air outlet pipe are both connected to the center injection pipe, and the height of the air outlet pipe in the vertical direction is higher than the height of the second air inlet pipe in the vertical direction.

[0006] Preferably in the present technical solution, the center injection pipe is a circular tubular structure, and the protective component includes: a connecting shell, the connecting shell is sleeved on the outside of the center injection pipe, the axis of the connecting shell coincides with the axis of the center injection pipe, the first end of the connecting shell is connected to the intermediate package, and the second end of the connecting shell is connected to the nozzle package.

[0007] Preferably, the first end of the connecting shell is connected to the tundish via an elastic compensating member, and the elastic compensating member is used to form a flexible connection between the connecting shell and the tundish.

[0008] More preferably, the second end of the connecting shell is connected to the nozzle package via a stabilizing member, and the stabilizing member is used to limit relative displacement between the second end of the connecting shell and the nozzle package.

[0009] Preferably in the present technical solution, the elastic compensation part is a stainless steel tube or a stainless steel bellows, the stabilizing part is a circular tubular structure, and the tube diameter of the stabilizing part is larger than the tube diameter of the connecting shell, a first connecting part is provided in the middle of the center injection tube, and a second connecting part is provided at the first end of the stabilizing part, and the first connecting part can be connected to the second connecting part.

[0010] Preferably in the present technical solution, a plurality of filter layers are sequentially arranged inside the center injection pipe from top to bottom, the filter hole diameters of the plurality of filter layers decrease successively, and a molten steel buffer area is formed between adjacent filter layers and the center injection pipe, and the molten steel buffer area is used to store liquid steel.

[0011] Preferably, the multiple filter layers include: a first filter layer and a second filter layer, and the filter hole diameter of the first filter layer is larger than the filter hole diameter of the second filter layer.

[0012] Preferably in the present technical solution, a heating device is further provided on the outside of the center pouring pipe, and the heating device is used to heat the molten steel inside the center pouring pipe.

[0013] Preferably in the present technical solution, the heating device is of a tubular structure, and the heating device comprises, from the inside to the outside, a heating supplement layer, a thermal insulation layer, an electromagnetic heating layer and a protective layer. The heating supplement layer heats the molten steel inside the center injection pipe by thermal radiation, the thermal insulation layer is used to reduce the heat loss of the molten steel inside the center injection pipe, the electromagnetic heating layer is used to increase the temperature of the heating supplement layer, and the protective layer is used to protect the heating supplement layer, the thermal insulation layer and the electromagnetic heating layer.

[0014] Preferably, the heating supplement layer is a graphite tube, and the length of the heating supplement layer along the first direction covers the total length of multiple molten steel buffer areas along the first direction, and the first direction is parallel to the axial direction of the center injection pipe; the insulation layer is an aluminum silicate fiber blanket; the protective layer is asbestos cloth; and the electromagnetic heating layer is a spiral electromagnetic induction coil.

[0015] Preferably in the present technical solution, a stopper rod structure is provided in the tundish, and the stopper rod structure is used to adjust the flow rate of the molten steel.

[0016] Preferably in the present technical solution, the stopper rod structure includes: a stopper rod, a nozzle and a seat brick arranged in sequence from top to bottom, the seat brick is used to be fixed to the inner wall of the tundish, the nozzle is connected to the seat brick, and a flow channel is provided on the seat brick, the nozzle is connected to the center injection pipe through the flow channel, the bottom end of the stopper rod is provided with an arc-shaped groove, the top end of the nozzle is an arc-shaped end, and the arc-shaped end is adapted to the arc-shaped groove.

[0017] Preferably in the present technical solution, an annular filter plate is further provided between the stopper rod and the water inlet, and the annular filter plate is used to filter the molten steel flowing into the water inlet.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The tundish pouring system protects the center pouring pipe in the protective cavity through the protective cavity formed between the protective component, the tundish and the nozzle package, and constantly injects protective gas into the protective cavity through the first air inlet pipe, so that the center pouring pipe is always under the protection of the protective gas. When the connection between the center pouring pipe, the tundish and the nozzle package is not tightly sealed, it will not cause oxidation of the molten steel in the center pouring pipe, thereby reducing the adverse effects on the production of wide ultra-thin nanocrystalline strips.

[0020] At the same time, after the molten steel is buffered and diverted by the multi-stage filtration layer in the center injection pipe, the molten steel turns into small liquid drips, thereby reducing the impact on the liquid surface of the nozzle package, thereby reducing the instability of the strip making process and thickness caused by the fluctuation of the molten steel level in the nozzle package.

[0021] The present invention can solve the technical problems of a large increase in the oxygen content of the molten steel caused by poor sealing during the casting process of wide ultra-thin nanocrystalline strips, and a large amount of oxide inclusions in the molten steel washed out, resulting in strip breakage and deterioration in strip performance during the strip making process. At the same time, it can solve the technical problems of large heat loss of molten steel in the injection pipe and difficulty in reheating the high-speed moving molten steel in the prior art.

[0022] At the same time, induction heating of the graphite tube for supplementary heating can quickly adjust the temperature of the molten steel, so that the temperature fluctuation of the molten steel in the tundish is within 3 degrees Celsius during the entire bottom pouring process, which meets the temperature control accuracy requirements required for the continuous preparation of wide ultra-thin nanocrystalline strips. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A perspective view of the present invention;

[0024] Figure 2 is a cross-sectional view of the present invention;

[0025] Figure 3 For the present invention Figure 2 Enlarged view of part A;

[0026] Figure 4 A cross-sectional view of a stopper rod structure proposed in the present invention;

[0027] Figure 5 A three-dimensional diagram of another stopper rod structure proposed by the present invention;

[0028] Figure 6 For the present invention Figure 5 Cross-sectional view of the middle stopper structure.

[0029] In the figure: 1. stopper rod; 15. arc-shaped groove; 2. water inlet; 3. seat brick; 31. flow channel; 4. annular filter plate; 5. tundish; 6. elastic compensation part; 7. heating device; 71. heating layer; 72. insulation layer; 73. electromagnetic heating layer; 74. electromagnetic induction coil; 75. protective layer; 8. center injection pipe; 81. second air inlet pipe; 82. air outlet pipe; 83. first filter layer; 84. second filter layer; 85. molten steel buffer area; 86. first connecting piece; 9. stabilizing piece; 91. first air inlet pipe; 92. second connecting piece; 10. connecting shell. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] It should be noted that, in the description of the present invention, the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0032] Furthermore, it should be understood that for the sake of ease of description, the sizes of the various components shown in the drawings are not drawn according to actual proportions. For example, the thickness or width of certain layers may be exaggerated relative to other layers.

[0033] It should be noted that like numbers and letters represent similar items in the following figures, so once an item is defined or described in one figure, it will not need to be further discussed and described in detail in the description of the subsequent figures.

[0034] like Figure 1 and Figure 2 As shown, the present invention provides a technical solution: a tundish pouring system comprising a tundish 5, a nozzle bag (not shown), and a center pouring pipe 8. In the prior art, the first end of the center pouring pipe 8 is connected to the tundish 5, and the second end of the center pouring pipe 8 is connected to the nozzle bag. Through the center pouring pipe 8, molten steel in the tundish 5 can be transported to the nozzle bag. It should be noted that during use, to maintain the stability of the liquid level in the nozzle bag, the center pouring pipe 8 generally needs to extend into the interior of the molten steel in the nozzle bag. Because the center pouring pipe 8 transports molten steel over a long period of time, it is also a consumable part. Its ends are generally connected to the tundish 5 and the nozzle bag, respectively, via detachable structures. Because this is a highly mature prior art, the detachable structure is not shown in the figure. It should also be noted that in the present invention, the shape and structure of the tundish 5, center pouring pipe 8, and nozzle bag are not limited in any way; they can be of any structure. The tundish 5 shown in the present invention is a cylindrical shell structure, and the center pouring pipe 8 is a quartz tube with a circular tubular structure.

[0035] As can be seen from the above, in the present invention, the tundish 5 is used to receive molten steel. The nozzle bag is used to receive molten steel from the tundish 5. In the prior art, the center injection pipe 8 is exposed to the air. If the connection between the center injection pipe 8 and the tundish 5 or the nozzle bag leaks, it can easily cause oxidation of the molten steel. Therefore, in the present invention, a protective assembly and a first air inlet pipe 91 are also required. The protective assembly is disposed between the tundish 5 and the nozzle bag, and a sealed protective cavity is formed between the tundish 5, the nozzle bag, and the protective assembly. The center injection pipe 8 is located within the protective cavity. The first air inlet pipe 91 is connected to the protective cavity and is used to supply protective gas to the protective cavity. During the production process, protective gas is constantly supplied to the protective cavity through the first air inlet pipe 91 (i.e., the first air inlet pipe 91 is always maintained at a positive pressure to prevent external air from entering the protective cavity). The protective gas can then protect the molten steel in the center injection pipe 8.

[0036] It should be clear that in order to further ensure that the molten steel inside the center injection pipe 8 will not be oxidized. The present invention also includes a second air inlet pipe 81 and an air outlet pipe 82, and the second air inlet pipe 81 and the air outlet pipe 82 are both connected to the center injection pipe 8. The second air inlet pipe 81 is mainly used to input protective gas into the interior of the center injection pipe 8, while the air outlet pipe 82 is mainly used to output protective gas. In one embodiment of the present invention, the protective gas can be an inert gas with a density greater than that of air, such as argon or nitrogen. When the density of the protective gas is greater than that of air, when designing, the height of the air outlet pipe 82 in the vertical direction is higher than the height of the second air inlet pipe 81 in the vertical direction.

[0037] Before pouring, shielding gas is introduced into the shielding chamber and center injection pipe 8 through the first and second inlet pipes 91 and 81, respectively. By slowly introducing shielding gas, it displaces the air in the shielding chamber, center injection pipe 8, and nozzle pack from bottom to top. This bottom-up movement of shielding gas ensures complete replacement of all air within the system, preventing oxidation and contamination of the molten steel during transportation. Once air displacement within the center injection pipe 8 and nozzle pack is complete, the second inlet pipe 81 and outlet pipe 82 are closed.

[0038] It should be clear that in the present invention, Figure 1 and Figure 2 As shown, the center injection pipe 8 is a circular tubular structure. The protective assembly includes a connecting shell 10, which is sleeved onto the outside of the center injection pipe 8. The axis of the connecting shell 10 coincides with the axis of the center injection pipe 8. The first end of the connecting shell 10 is connected to the tundish 5, and the second end of the connecting shell 10 is connected to the nozzle package. The cavity formed between the connecting shell 10, the tundish 5, and the nozzle package is the protective cavity. It should be understood that the connecting shell 10 here can not only protect the center injection pipe 8 through the protective gas inside it, but also provide physical protection for the center injection pipe 8.

[0039] To further enhance the practicality of the present invention, the first end of the connecting shell 10 is connected to the tundish 5 via an elastic compensating member 6. This member 6 provides a flexible connection between the shell 10 and the tundish 5. The primary purpose of providing this elastic compensating member 6 is to allow for a certain amount of play and movement in the connecting shell 10, facilitating ease of use and installation. In this embodiment, the elastic compensating member 6 is a stainless steel tube or a stainless steel bellows.

[0040] In order to further enhance the practicality of the present invention, the second end of the connecting shell 10 is connected to the nozzle package via a stabilizing member 9, and the stabilizing member 9 is used to limit the relative displacement between the second end of the connecting shell 10 and the nozzle package. Figure 1 and Figure 2As shown, the stabilizer 9 is a circular tubular structure, and the diameter of the stabilizer 9 is larger than the diameter of the connecting shell 10. A first connecting member 86 is provided in the middle of the injection tube 8, and a second connecting member 92 is provided at the first end of the stabilizer 9. The first connecting member 86 can be connected to the second connecting member 92.

[0041] It should be clear that the first connecting member 86 and the second connecting member 92 are located in the middle of the injection tube 8. In the prior art, only the two ends of the injection tube 8 are fixed. In the present invention, the middle part of the injection tube 8 is fixed by the stabilizer 9, the first connecting member 86 and the second connecting member 92. This makes the injection tube 8 more stable and less likely to produce relative displacement with the nozzle package. In the present invention, the stabilizer 9 is a circular tubular structure, which can be directly sleeved on the nozzle package. Or the stabilizer 9 is fixed to the top of the nozzle package. Specifically, the second end of the stabilizer 9 can be welded to the nozzle package, or the second end of the stabilizer 9 can be threadedly connected to the nozzle package through a flange (not shown in the figure), and there is no restriction on its specific connection form. At the same time, since the diameter of the stabilizer 9 is larger than the diameter of the connecting shell 10 (it can be clearly known that the diameter of the injection tube 8 is also smaller than that of the stabilizer 9), the stabilizer 9 can be more stably connected to the nozzle package.

[0042] Meanwhile, in another embodiment of the present invention, as Figure 2 and Figure 3 As shown. The interior of the center pouring pipe 8 is sequentially provided with a first filter layer 83 and a second filter layer 84 from top to bottom. The filter hole diameter of the first filter layer 83 is larger than the filter hole diameter of the second filter layer 84. A molten steel buffer area 85 is formed between the center pouring pipe 8, the first filter layer 83 and the second filter layer 84. The molten steel buffer area 85 is used to store liquid molten steel. It should be understood that since the filter hole diameter of the first filter layer 83 is larger than the filter hole diameter of the second filter layer 84. Therefore, the flow rate of the molten steel through the first filter layer 83 is greater than the flow rate through the second filter layer 84, which allows the molten steel to accumulate in the molten steel buffer area 85. In other words, the molten steel is dynamic. During the pouring process, the molten steel flows out of the tundish 5, flows through the center pouring pipe 8, and then enters the nozzle bag. When the molten steel passes through the center pouring pipe 8, the molten steel is buffered at the first filter layer 83 and the second filter layer 84. The molten steel will accumulate in the molten steel buffer area 85, forming a section of dynamically stable molten steel, that is, a steel storage pool. It should be noted that, while only two filter layers are provided in this embodiment, multiple filter layers may be provided in other embodiments. The filter pore diameters of the multiple filter layers decrease from top to bottom. Adjacent filter layers are spaced a certain distance apart, and the area separated by the adjacent filter layers is the molten steel buffer area 85.

[0043] It should be noted that, in the present invention, the filter layer can adopt any form of product. In one embodiment of the present invention, the filter layer is a zirconia foam ceramic filter screen. The filtration pore size of the first filter layer 83 is controlled to be greater than or equal to 25ppi, and less than or equal to 30ppi. Specifically, it can be any one of 25ppi, 26ppi, 27ppi, 28ppi, 29ppi and 30ppi, or it can be any pore size between the two adjacent pores. The filtration pore size of the second filter layer 84 is controlled to be greater than or equal to 15ppi, and less than or equal to 20ppi. Specifically, it can be any one of 15ppi, 16ppi, 17ppi, 18ppi, 19ppi and 20ppi, or it can be any pore size between the two adjacent pores. By designing such pores, not only can the above-mentioned molten steel buffer zone 85 be formed, but it can also filter out slag and impurities in the molten steel.

[0044] It should also be noted that the large flow of molten steel flowing out of the tundish 5 is converted into small drops after being buffered and diverted by the first and second filter layers 83 and 84. This reduces the impact on the molten steel surface in the nozzle ladle, thereby reducing the instability of the strip making process and thickness caused by liquid level fluctuations.

[0045] In order to further enhance the practicality of the present invention, in another embodiment of the present invention. A heating device 7 is further provided on the outside of the center injection pipe 8, and the heating device 7 is used to heat the molten steel inside the center injection pipe 8. Therefore, the heating device 7 can be fully utilized to supplement the heat of the molten steel in the molten steel buffer area 85 to make up for the heat lost by the molten steel during the flow. It should be clear that in the present invention, the heating device 7 can be used to cover the entire center injection pipe 8 along the axial direction of the center injection pipe 8. However, as can be seen from the above, in the center injection pipe 8 of the present invention, the flow rate of the molten steel in the center injection pipe 8 located in the upper section of the molten steel buffer area 85 is faster, and the molten steel in the center injection pipe 8 located in the lower section of the molten steel buffer area 85 is in the form of droplets. Therefore, in other embodiments of the present invention, the heating device 7 can be covered in the molten steel buffer area 85 in the center injection pipe 8 to supplement the heat of the molten steel therein.

[0046] It should be understood that, in the present invention, the heating device 7 can be any device capable of heating. For example, a resistance heating device and an electromagnetic heating device. Specifically, Figure 3 As shown, the heating device 7 of the present invention has a tubular structure, and the heating device 7 includes, from the inside to the outside, a heating layer 71, a thermal insulation layer 72, an electromagnetic heating layer 73 and a protective layer 75. The heating layer 71 heats the molten steel inside the center injection pipe 8 by thermal radiation, the thermal insulation layer 72 is used to reduce the heat loss of the molten steel inside the center injection pipe 8, the electromagnetic heating layer 73 is used to increase the temperature of the heating layer 71, and the protective layer 75 is used to protect the heating layer 71, the thermal insulation layer 72 and the electromagnetic heating layer 73.

[0047] As a preferred embodiment of the present invention, the supplementary heating layer 71 is a graphite tube. In the present invention, the supplementary heating layer 71 can also be other types of pipes capable of rapid heating through electromagnetic induction, such as heat-resistant steel pipes. The present invention uses induction heating to heat the graphite tube to 1000 degrees Celsius within 30 seconds. By simultaneously heating the molten steel in the center injection tube 8 through graphite tube supplementary heating and electromagnetic induction heating, heating efficiency and stability can be significantly improved. Furthermore, when there is no molten steel in the center injection tube 8, the supplementary heating through thermal radiation from the graphite tube can still maintain a relatively high temperature. Therefore, to enhance the supplementary heating effect of the supplementary heating layer 71, it is readily apparent that the length of the supplementary heating layer 71 along the first direction needs to cover the total length of the molten steel buffer area 85 along the first direction, where the first direction is parallel to the axis of the center injection tube 8. Here, "covering" means that the supplementary heating layer 71 is able to enclose all of the molten steel buffer areas 85. That is, the projections of all of the molten steel buffer areas 85 along the second direction are within the projections formed by the supplementary heating layer 71 along the second direction. The second direction is perpendicular to the first direction.

[0048] It should be understood that, in the present invention, the thermal insulation layer 72 can be any material that can insulate heat and prevent heat loss. For example, it can be an aluminum silicate fiber blanket. The thermal insulation layer 72 can improve the safety of the furnace body while insulating and retaining heat. The protective layer 75 is mainly for physical protection, so it can be a structure of any material. For example, a ceramic tube or asbestos cloth. The electromagnetic heating layer 73 is a spiral electromagnetic induction coil 74. Preferably, the spiral axis of the electromagnetic induction coil 74 coincides with the axis of the heating layer 71.

[0049] In other embodiments of the present invention, the heating device 7 may also be provided with a temperature measuring port for measuring temperature, such as an infrared temperature measuring port. This is used to monitor the temperature generated by the heating device 7 in real time. The heating device further comprises an induction coil adjustment unit, a temperature measuring component, and a PLC control unit, wherein the induction coil adjustment unit can adjust the temperature by adjusting the electromagnetic induction coil 74; the temperature measuring component can measure the temperature of the molten steel at the corresponding position in the middle injection pipe 8 through the temperature measuring port; and the PLC control unit is also connected to the electromagnetic induction coil 74 adjustment unit to achieve automatic temperature adjustment and maintain the stability of the molten steel temperature. The above functions can all be easily implemented and are relatively mature existing technologies, so they will not be elaborated on here.

[0050] In order to further improve the practicality of the present invention, Figure 4As shown, a stopper rod structure is provided within the tundish 5, which is used to regulate the flow of molten steel. It should be understood that the stopper rod structure in the present invention comprises: a stopper rod 1, a nozzle 2, and a support brick 3, arranged in order from top to bottom. The support brick 3 is secured to the inner wall of the tundish 5. The nozzle 2 is connected to the support brick 3, and a flow channel 31 is defined in the support brick 3. The nozzle 2 is connected to the center pouring pipe 8 through the flow channel 31. The bottom end of the stopper rod 1 is defined by an arcuate groove 15, and the top end of the nozzle 2 is an arcuate end that mates with the arcuate groove 15.

[0051] It should be noted that the top of the nozzle 2 is higher than the height of the base brick 3. When in use, the molten steel in the tundish 5 does not exceed the stopper rod 1. When the molten steel in the tundish 5 needs to flow from the tundish into the center pouring pipe 8, its flow path is as follows: Figure 4 As shown in the route a in FIG. Therefore, when this kind of stopper rod structure can prevent heavy impurities from entering the nozzle 2, it can ensure the purity of the molten steel flowing into the nozzle. Figure 5 and Figure 6 As shown, it is easy to imagine that, in order to further improve the purity of the molten steel, based on the above-mentioned stopper rod structure, an annular filter plate 4 can be further provided between the stopper rod 1 and the nozzle 2. The annular filter plate 4 is used to filter the molten steel flowing into the nozzle 2. The annular filter plate 4 can slow the flow of the circulating molten steel and block slag, and can also serve to position the stopper rod 1.

[0052] It should be understood that the annular filter plate 4 can be a ceramic plate with filter holes, or a foam ceramic, such as zirconium oxide foam ceramic, without any limitation on its type.

[0053] All the tundish pouring systems proposed in the embodiments of the present invention can be applied to the tundish bottom pouring process of nanocrystalline planar flow casting strip. Of course, the present invention is not limited thereto and can also be applied to other types of tundish bottom pouring processes in the smelting field.

[0054] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A tundish pouring system, characterized in that: include: a tundish (5), the tundish (5) being used to receive molten steel; a nozzle package, the nozzle package being used to receive molten steel from the tundish (5); a center pouring pipe (8), wherein a first end of the center pouring pipe (8) is connected to the tundish (5), a second end of the center pouring pipe (8) is connected to the nozzle bag, and the molten steel in the tundish (5) can be transported to the nozzle bag through the center pouring pipe (8), and the second end of the center pouring pipe (8) extends to the interior of the molten steel in the nozzle bag; A stabilizing member (9), the stabilizing member (9) is in a circular tubular structure, a first connecting member (86) is provided in the middle of the center injection tube (8), a second connecting member (92) is provided at the first end of the stabilizing member (9), the first connecting member (86) and the second connecting member (92) are connected; the middle of the center injection tube (8) is fixed by the stabilizing member (9), the first connecting member (86) and the second connecting member (92); The two ends of the center injection pipe (8) are respectively connected to the tundish (5) and the nozzle pack via a detachable structure; A protective assembly, the protective assembly being arranged between the tundish (5) and the nozzle package, and a sealed protective cavity being formed between the tundish (5), the nozzle package and the protective assembly, the center injection pipe (8) being located in the protective cavity; a first air inlet pipe (91), the first air inlet pipe (91) being in communication with the protective cavity, and the first air inlet pipe (91) being used to transport protective gas to the protective cavity; a second air inlet pipe (81) and an air outlet pipe (82), wherein the second air inlet pipe (81) and the air outlet pipe (82) are both connected to the center injection pipe (8), and the height of the air outlet pipe (82) in the vertical direction is higher than the height of the second air inlet pipe (81) in the vertical direction; The center injection pipe (8) is a circular tubular structure, and the protective component includes: A connecting shell (10), wherein the connecting shell (10) is sleeved on the outside of the center injection pipe (8), the axis of the connecting shell (10) coincides with the axis of the center injection pipe (8), the first end of the connecting shell (10) is connected to the tundish (5), and the second end of the connecting shell (10) is connected to the nozzle bag; wherein the diameter of the stabilizing member (9) is larger than the diameter of the connecting shell (10); The first end of the connecting shell (10) is connected to the tundish (5) via an elastic compensating member (6), and the elastic compensating member (6) is used to form a flexible connection between the connecting shell (10) and the tundish (5); The elastic compensating member (6) is a stainless steel bellows.

2. The tundish pouring system according to claim 1, characterized in that: The second end of the connecting shell (10) is connected to the nozzle package via a stabilizing member (9), and the stabilizing member (9) is used to limit relative displacement between the second end of the connecting shell (10) and the nozzle package.

3. The tundish pouring system according to claim 1, characterized in that: The interior of the center injection pipe (8) is provided with a plurality of filter layers from top to bottom, the filter hole diameters of the plurality of filter layers decrease in sequence, and a molten steel buffer area (85) is formed between the adjacent filter layers and the center injection pipe (8), and the molten steel buffer area (85) is used to store liquid molten steel.

4. The tundish pouring system according to claim 3, characterized in that: The multiple filter layers include: a first filter layer (83) and a second filter layer (84); the filter hole diameter of the first filter layer (83) is larger than the filter hole diameter of the second filter layer (84).

5. The tundish pouring system according to claim 3, characterized in that: A heating device (7) is further provided on the outside of the center pouring pipe (8), and the heating device (7) is used to heat the molten steel inside the center pouring pipe (8).

6. The tundish pouring system according to claim 5, characterized in that: The heating device (7) is a tubular structure, and the heating device (7) includes, from the inside to the outside, a heating layer (71), a thermal insulation layer (72), an electromagnetic heating layer (73) and a protective layer (75). The heating layer (71) heats the molten steel inside the center injection pipe (8) by thermal radiation. The thermal insulation layer (72) is used to reduce the heat loss of the molten steel inside the center injection pipe (8). The electromagnetic heating layer (73) is used to increase the temperature of the heating layer (71). The protective layer (75) is used to protect the heating layer (71), the thermal insulation layer (72) and the electromagnetic heating layer (73).

7. The tundish pouring system according to claim 6, characterized in that: The heating supplement layer (71) is a graphite tube, and the length of the heating supplement layer (71) along the first direction covers the total length of multiple steel liquid buffer areas (85) along the first direction, and the first direction is parallel to the axial direction of the center injection pipe (8); the thermal insulation layer (72) is an aluminum silicate fiber blanket; the protective layer (75) is asbestos cloth; and the electromagnetic heating layer (73) is a spiral electromagnetic induction coil (74).

8. The tundish pouring system according to claim 1, characterized in that: A stopper rod structure is provided in the tundish (5), and the stopper rod structure is used to adjust the flow rate of the molten steel.

9. The tundish pouring system according to claim 8, characterized in that: The stopper rod structure comprises: a stopper rod (1), a nozzle (2) and a seat brick (3) arranged in sequence from top to bottom, the seat brick (3) being used to be fixed to the inner wall of the tundish (5), the nozzle (2) being connected to the seat brick (3), and a flow channel (31) being provided on the seat brick (3), the nozzle (2) being connected to the center injection pipe (8) through the flow channel (31), the bottom end of the stopper rod (1) being provided with an arc-shaped groove (15), the top end of the nozzle (2) being an arc-shaped end, and the arc-shaped end being adapted to the arc-shaped groove (15).

10. The tundish pouring system according to claim 9, characterized in that: An annular filter plate (4) is further provided between the stopper rod (1) and the water inlet (2), and the annular filter plate (4) is used to filter the molten steel flowing into the water inlet (2).

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