Multi-strand continuous casting machine and control method thereof

Abstract

The invention provides a multi-strand continuous casting machine and a control method thereof. The multi-strand continuous casting machine comprises a steel ladle; the steel ladle is connected with the at least two intermediate tanks through the steel ladle long nozzles respectively; the interior of the intermediate tank is divided into a mixing cavity and a pouring cavity through a partition plate structure, a plurality of flow uniformizing holes are formed in the partition plate structure so that molten steel in the mixing cavity can flow into the pouring cavity in a split mode, and a plurality of molten steel outlets are evenly distributed in the wall face, opposite to the partition plate structure, of the pouring cavity at intervals. The plurality of molten steel outlets are respectively connected with a plurality of submersed nozzles which are uniformly distributed at intervals; the at least two intermediate tanks are respectively connected with the crystallizer through a plurality of submersed nozzles. According to the multi-flow continuous casting machine, the design of the two intermediate tanks is adopted, the multi-flow continuous casting machine can be matched with a large converter, molten steel is fully mixed and purified in the intermediate tanks, the uniformity and adaptability of a molten steel flow path are guaranteed, the multi-flow continuous casting machine can be used for producing large square billets or round billets, the quality of casting billets can be guaranteed, and the multi-flow continuous casting machine can be matched with the large converter.

Description

Technical Field

[0001] This invention relates to the field of steel production technology, and more particularly to a multi-strand continuous casting machine and its control method, especially to a multi-strand continuous casting machine and its control method in the steelmaking continuous casting process. Background Technology

[0002] With the development of steel enterprises, the nominal capacity of converters is getting larger and larger. Increased capacity reduces the production cost per ton of steel. However, when the nominal capacity of a converter exceeds 150t (especially 200t), slab continuous casting machines have a large production capacity, and large-capacity converters are well-matched with them. But for square billet continuous casting machines, due to their limited flow rate (the number of billets that a single casting machine can cast simultaneously, i.e., the number of independent flow channels for simultaneous casting) and low capacity, square billet continuous casting machines cannot be used in conjunction with large converters.

[0003] For example, the maximum number of streams in current small billet continuous casting machines is 12. Since small billets are mainly used for building materials and ordinary steel production, the quality requirements for the cast billets are not high, so a double tundish can be used. However, large billets (especially those with a cross-section greater than 300×400mm) are generally used to produce special steel, which has high requirements for the quality of the cast billets. A single tundish is generally used because the flow field of a single tundish is better, which is beneficial to improving the quality of the cast billets of large billets. The number of streams in large billet continuous casting machines is generally 7-8. Since the number of streams is relatively small, if a single tundish is used and it is matched with a large converter of 200t or above, the continuous casting needs to be centered, the converter output will be reduced, and output needs to be sacrificed to ensure the quality of the cast billets. If a double tundish is used, the flow field path in the tundish will cause problems with the quality of the cast billets of large billet continuous casting machines due to the different lengths of multiple paths in the flow field (such as the impact zone of some shorter paths being smaller due to the different lengths of multiple paths in the flow field, resulting in the situation that inclusions in the steel flow do not have time to float to the surface and are discharged before they can float to the surface).

[0004] Therefore, this invention proposes a multi-strand continuous casting machine and its control method to overcome the shortcomings of the prior art. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-strand continuous casting machine and its control method, which can use a double tundish to produce large square billets or round billets, and can ensure the adaptability of the flow field path in the tundish and the quality of the billet. This multi-strand continuous casting machine can be matched with a large converter.

[0006] The objective of this invention can be achieved through the following methods: This invention provides a multi-strand continuous casting machine, the multi-strand continuous casting machine comprising: Ladle of molten steel; At least two intermediate tanks, wherein the molten steel ladle is connected to the long water inlets of the at least two intermediate tanks respectively through the long water inlet of the ladle; The intermediate tank has a partition structure inside, which divides the interior of the intermediate tank into a mixing chamber and a casting chamber. The mixing chamber is connected to the long water inlet. The partition structure has multiple flow equalization holes to allow the molten steel in the mixing chamber to flow into the casting chamber. The casting chamber and the wall opposite to the partition structure have multiple molten steel outlets spaced apart and evenly distributed. The multiple molten steel outlets are respectively connected to multiple immersion nozzles spaced apart and evenly distributed. The crystallizer, at least two of the intermediate tanks are connected to the crystallizer via a plurality of the immersion nozzles.

[0007] In a preferred embodiment of the present invention, the mixing chamber is a long strip-shaped chamber, and the long water inlet and the partition structure are located at both ends of the mixing chamber along the length direction.

[0008] In a preferred embodiment of the present invention, the casting cavity is connected to the mixing cavity through a constriction section thereon, the partition structure is disposed on the constriction section, and the chamber of the casting cavity expands to both sides relative to the constriction section, so that the casting cavity forms a flat wall on the side opposite to the partition structure, and a plurality of molten steel outlets are spaced apart and evenly arranged along the length direction of the wall.

[0009] In a preferred embodiment of the present invention, the partition structure includes a first partition and two second partitions located on both sides of the first partition, the plurality of flow equalization holes are located on the two second partitions, the two opposite edges of the first partition are connected to one side edge of the two second partitions, and the other opposite side edge of the two second partitions is connected to the inner wall of the intermediate tank. The angle between the surface of the first partition and the surface of the second partition is an obtuse angle. When the partition structure is installed, the first partition protrudes into the mixing cavity, and the surfaces of the two second partitions face the two sides of the partition structure, so as to evenly distribute the molten steel to the casting cavity.

[0010] In a preferred embodiment of the present invention, a temperature measuring point is provided at the location of the casting cavity and the plurality of molten steel outlets, and a temperature measuring element is provided at the temperature measuring point.

[0011] In a preferred embodiment of the present invention, a stopper rod is provided at each of the plurality of molten steel outlets.

[0012] In a preferred embodiment of the present invention, the multi-strand continuous casting machine further includes multiple straightening machines, and a fan-shaped section and a fixed section are sequentially connected between the outlet of the crystallizer and the straightening machine, and multiple clamping rollers are respectively provided on both sides of the fan-shaped section and the fixed section.

[0013] This invention provides a multi-strand continuous casting control method, which is implemented using the aforementioned multi-strand continuous casting machine. The multi-strand continuous casting control method includes the following steps: Step S1: Pour the molten steel into a ladle; Step S2: The molten steel in the ladle is injected into the two intermediate tanks through the two long ladle nozzles respectively; Step S201: The molten steel enters the mixing chamber through the long water inlet on the intermediate tank, and the molten steel is temporarily retained in the mixing chamber to remove floating inclusions; Step S202: The mixed and purified molten steel is evenly distributed into the casting cavity through multiple flow equalization holes on the partition structure; Step S3: The molten steel in the casting cavity is injected into the crystallizer through multiple submerged entry nozzles and multiple flow paths, and a billet with a shell is formed in the crystallizer.

[0014] In a preferred embodiment of the present invention, after step S3, the method further includes: Step S4: The billet with the shell is conveyed to the fan-shaped section, and the clamping rollers located on both sides of the fan-shaped section support and cool the billet; Step S5: The completely solidified billet is conveyed to the fixed section, and the clamping rollers located on both sides of the fixed section guide and cool the billet again. Step S6: The billet is conveyed to a straightening machine to straighten it; Step S7: The straightened billet is cut and removed from the production line using a billet removal device to complete the production of large square billets or round billets.

[0015] In a preferred embodiment of the present invention, in step S3, the flow rate of molten steel at multiple molten steel outlets on the casting cavity is independently controlled by multiple stoppers.

[0016] Based on the above, the features and advantages of the multi-strand continuous casting machine and its control method of the present invention are as follows: At least two intermediate ladles are installed below the ladle, allowing molten steel from the ladle to flow into both ladles simultaneously. The multiple ladles provide more flow paths to match the large converter and meet the casting requirements for large square or round billets. To address the problem of poor flow field stability in the ladles leading to reduced billet quality, this invention adds a baffle structure inside the ladles. This baffle structure divides the interior of the ladles into a mixing chamber and a pouring chamber. The mixing chamber is connected to the long water inlet, providing sufficient space for the molten steel initially entering the ladles, ensuring thorough mixing within the mixing chamber and removing inclusions after they float to the surface. Furthermore, the baffle structure has multiple flow equalization holes, and multiple molten steel outlets are spaced apart and evenly distributed on the opposite wall of the pouring chamber. These flow equalization holes and outlets distribute the molten steel evenly, further ensuring the quality of the cast billets. Attached Figure Description

[0017] The following figures are intended only to illustrate and explain the present invention and do not limit the scope of the invention. Wherein: Figure 1 This is a schematic diagram of the structure of the multi-strand continuous casting machine of the present invention; Figure 2 This is a schematic diagram showing the arrangement of the molten steel ladle and tundish in the multi-strand continuous casting machine of the present invention; Figure 3 This is a schematic diagram of the internal structure of the two intermediate tanks in the multi-strand continuous casting machine of the present invention; Figure 4 This is a side cross-sectional view of the intermediate jar in the multi-strand continuous casting machine of the present invention; Figure 5 This is a front view of the diaphragm structure in the multi-strand continuous casting machine of the present invention; Figure 6 This is a side view of the diaphragm structure in the multi-strand continuous casting machine of the present invention; Figure 7 This is a top view of the diaphragm structure in the multi-strand continuous casting machine of the present invention.

[0018] The reference numerals in the accompanying drawings of this invention are: 1. Ladle; 2. Ladle nozzle; 3. Tundish; 301. Outer shell; 3011. Trunnion; 302. Mixing chamber; 303. Casting chamber; 304. Long water inlet; 305. Baffle structure; 3051. Flow equalization hole; 3052. First baffle; 3053. Second baffle; 306. Stopper rod; 307. Molten steel outlet; 308. Temperature measuring point; 309. Refractory layer; 310. Narrowing section; 4. Submerged entry nozzle; 5. Crystallizer; 6. Vibration device; 7. Fan-shaped section; 8. Fixed section; 9. Straightening machine; 10. Cast billet. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0020] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] Implementation Method 1

[0023] like Figures 1 to 7 As shown, the present invention provides a multi-strand continuous casting machine, which includes a ladle 1, a crystallizer 5, and at least two tundishes 3. The ladle 1 is connected to the long water inlets 304 of the at least two tundishes 3 through long water inlets 2 (or protective pipes). The tundishes 3 have a partition structure 305 inside, which divides the interior of the tundishes 3 into a mixing chamber 302 and a pouring chamber 303. The mixing chamber 302 is connected to the long water inlets 304. The partition structure 305 has multiple flow equalization holes 3051 to allow the molten steel in the mixing chamber 302 to flow into the pouring chamber 303. The pouring chamber 303 and the wall opposite to the partition structure 305 have multiple molten steel outlets 307 spaced apart and evenly distributed. The multiple molten steel outlets 307 are connected to multiple immersion nozzles 4 spaced apart and evenly distributed. The at least two tundishes 3 are connected to the crystallizer 5 through multiple immersion nozzles 4.

[0024] In this invention, at least two intermediate ladles 3 are provided below the ladle 1. The molten steel in the ladle 1 can flow into at least two intermediate ladles 3 at the same time. The arrangement of multiple intermediate ladles 3 can provide more flow paths so that the continuous casting machine can be matched with the large converter to meet the casting requirements of large square billets or round billets.

[0025] In this invention, to address the problem of poor flow field stability in the intermediate tank 3 leading to reduced billet quality, a baffle structure 305 is added inside the intermediate tank 3. The baffle structure 305 divides the interior of the intermediate tank 3 into a mixing chamber 302 and a pouring chamber 303. The mixing chamber 302 is connected to the long water inlet 304 on the intermediate tank 3, providing sufficient space for the molten steel initially entering the intermediate tank 3, ensuring thorough mixing within the mixing chamber 302 and removing inclusions from the molten steel after they float to the surface. Furthermore, multiple flow equalization holes 3051 are provided on the baffle structure 305, and multiple molten steel outlets 307 are spaced apart and evenly distributed on the wall surface of the pouring chamber 303 opposite to the baffle structure 305. The multiple flow equalization holes 3051 and multiple molten steel outlets 307 distribute and divert the molten steel evenly, further ensuring the quality of the billet.

[0026] In an optional embodiment of the present invention, such as Figure 1 As shown, the multi-strand continuous casting machine also includes multiple straighteners 9. A sector section 7 and a fixed section 8 are sequentially connected between the outlet of the crystallizer 5 and the straightener 9. Multiple clamping rollers are respectively provided on both sides of the sector section 7 and the fixed section 8. The sector segment 7 is composed of multiple segments arranged along an arc trajectory. Multiple clamping rollers (drive rollers and free rollers) are set on both sides of the sector segment 7. When the billet 10 is first output from the crystallizer 5, the inside of the billet 10 is still high-temperature liquid steel. Without external tight support, the thin outer shell of the billet 10 will bulge, deform, or even crack, leading to steel leakage. The sector segment 7 provides solid mechanical support for the billet 10 through the densely arranged clamping rollers, preventing it from bulging. In addition, the sector segment 7 can also provide the billet 10 with a precise movement path from arc to horizontal, guiding the billet 10 to run smoothly according to the set radius of curvature. The sector segment 7 also integrates a water spraying system, which sprays atomized water onto the surface of the billet 10 through nozzles arranged between two adjacent clamping rollers for forced cooling, so that the liquid steel inside the billet 10 continues to solidify until it is completely solidified. The fixed section 8 is located before the straightening machine 9. The fixed section 8 supports, guides and completely cools the fully solidified billet 10 and sends it to the straightening machine 9.

[0027] Specifically, the multi-strand continuous casting machine in this invention is an arc-shaped continuous casting machine, and the radius of the continuous casting machine can be, but is not limited to, R12 meters to R19 meters. The cross-section of the cast billet (large square billet) can be, but is not limited to, 300×400 square millimeters to 450×600 square millimeters; or the cross-section of the cast billet (round billet) is... 300 mm to 1000 mm. It adopts a double intermediate ladle 3 structure. Each intermediate ladle 3 can have, but is not limited to, 3 to 6 molten steel outlets 307. The two intermediate ladle 3 can have 6 to 12 molten steel outlets 307, that is, the amount of molten steel that can be poured can be 6 to 12.

[0028] Furthermore, such as Figure 1 As shown, the multi-strand continuous casting machine also includes a vibration device 6 installed on the crystallizer 5. Existing vibration equipment can be used here, which can make the crystallizer 5 perform high-frequency reciprocating motion through vibration, so as to achieve demolding of the billet 10.

[0029] In an optional embodiment of the present invention, such as Figures 2 to 4 As shown, the mixing chamber 302 is a long strip-shaped chamber. Along the length of the mixing chamber 302, the long water inlet 304 and the baffle structure 305 are located at both ends of the mixing chamber 302, which allows the molten steel to remain in the mixing chamber 302 for as long as possible, so as to ensure that the molten steel can be fully mixed in the mixing chamber 302, and that the non-metallic inclusions in the molten steel can be fully floated and fully absorbed by the covering agent, thereby ensuring the quality of the billet 10.

[0030] Furthermore, such as Figure 3 As shown, the casting cavity 303 is connected to the mixing cavity 302 through the constriction section 310 thereon. The baffle structure 305 is set on the constriction section 310. The cross-sectional area of ​​the constriction section 310 is smaller than that of the casting cavity 303. Along the length of the casting cavity 303, the chambers of the casting cavity 303 expand to both sides relative to the constriction section 310. This not only extends the length of the wall of the casting cavity 303 facing the steel output side, but also makes it easier for the casting cavity 303 to form a straight wall on the side opposite to the baffle structure 305. This allows multiple steel outlets 307 to be spaced apart and evenly arranged along the length of the straight wall on the side opposite to the baffle structure 305 of the casting cavity 303. This ensures that each flow path is independent and evenly distributed. The billets 10 of multiple flow paths can obtain the same cooling and process conditions, enabling the mass and stable production of high-quality products and avoiding product quality fluctuations.

[0031] Specifically, such as Figure 3As shown, the partition structure 305 includes a first partition 3052 and two second partitions 3053 located on both sides of the first partition 3052. Multiple flow equalization holes 3051 are located on the two second partitions 3053. The two opposite edges of the first partition 3052 are connected to one edge of each of the two second partitions 3053, and the other opposite edges of the two second partitions 3053 are connected to the inner wall of the intermediate tank 3. The included angle between the surfaces of the first partition 3052 and the second partitions 3053 is... With an obtuse angle, when the partition structure 305 is installed in the intermediate tank 3, the first partition 3052 protrudes into the mixing chamber 302, and the two second partitions 3053 face the two sides of the partition structure 305 respectively (i.e. towards the direction of expansion of the casting chamber 303 located on both sides of the constriction section 310), so that the molten steel can flow more evenly into the casting chamber 303 through the multiple uniform flow holes 3051 on the two second partitions 3053, thereby achieving the purpose of more easily and evenly distributing the flow in the casting chamber 303.

[0032] The first partition 3052 and the two second partitions 3053 may be integrally formed, but are not limited to.

[0033] In this invention, the number of uniform flow holes 3051 on each second partition 3053 may be, but is not limited to, 3 (i.e., the number of uniform flow holes 3051 on the entire partition structure 305 may be, but is not limited to, 6), and the diameter of the uniform flow holes 3051 may be, but is not limited to, 3. 100mm.

[0034] In an optional embodiment of the present invention, such as Figure 3 As shown, the casting cavity 303 and the multiple molten steel outlets 307 each have a temperature measuring point 308, and a temperature measuring element is installed at each temperature measuring point 308. A stopper rod 306 is installed at each of the multiple molten steel outlets 307. The stopper rod 306 is an existing structure, used to control the flow rate of the molten steel outlets 307 in real time to maintain the stability of the liquid level in the crystallizer 5.

[0035] Specifically, temperature measuring point 308 is located approximately 150mm to one side of stopper rod 306. It can continuously monitor the temperature of each flow path in real time via a temperature measuring element, thereby obtaining the molten steel temperature of each flow path. This provides real-time molten steel temperature data for the secondary cooling calculation model of each flow path (i.e., a preset calculation model used to calculate and control the cooling water volume and distribution in the secondary cooling zone (sector 7)). This provides fundamental data support for process calculations, improves the accuracy of temperature model calculations in steel production, and ultimately ensures the quality of the cast billet 10 for large square or round billets. The temperature measuring element can be, but is not limited to, a temperature sensor.

[0036] In an optional embodiment of the present invention, such as Figure 3 and Figure 4As shown, the intermediate tank 3 includes an outer shell 301, within which a mixing chamber 302 and a casting chamber 303 are formed. The inner wall of the outer shell 301 has a refractory layer 309. The refractory layer 309 may be, but is not limited to, refractory bricks.

[0037] In an optional embodiment of the present invention, such as Figure 3 As shown, a trunnion 3011 is provided on the top outer wall of the outer casing 301. The trunnion 3011 can be used as a hoisting fulcrum, and the crane hook can use the trunnion 3011 to hoist the intermediate tank 3 to the working position above the crystallizer 5.

[0038] The features and advantages of the multi-strand continuous casting machine of the present invention are as follows: First, the structure of this multi-strand continuous casting machine allows the production capacity of the large billet or round billet continuous casting machine to match the production capacity of a large converter of 200 tons or more, solving the long-standing bottleneck of "large converter matching small continuous casting". It eliminates the need for the converter to reduce its output to adapt to the continuous casting machine, thereby significantly improving the efficiency and economic benefits of the entire steelmaking process.

[0039] Second, this multi-flow continuous casting machine overcomes the defects of uneven flow field and insufficient floating of inclusions in the traditional double intermediate tank structure through the internal structural design of the intermediate tank 3. This allows it to produce high-quality billets 10 suitable for special steel while using a high-flow-rate double intermediate tank. The purity and internal quality of the billets 10 can be effectively guaranteed.

[0040] Third, the uniform flow field design in the intermediate tank 3 of this multi-flow continuous casting machine, combined with independent temperature measurement and flow control for each flow path, ensures that the billets 10 in multiple flow paths can obtain the same cooling and process conditions, enabling large-scale and stable production of high-quality products and avoiding product quality fluctuations.

[0041] Implementation Method 2

[0042] This invention provides a multi-strand continuous casting control method, which is implemented using the aforementioned multi-strand continuous casting machine. The multi-strand continuous casting control method includes the following steps: Step S1: Smelt qualified molten steel from a large converter (200t and above) and pour the molten steel into ladle 1; Step S2: Molten steel in ladle 1 is injected into two independent intermediate tanks 3 through two long ladle nozzles 2; Step S2 also includes, Step S201: Molten steel enters the mixing chamber 302 through the long water inlet 304 on the intermediate tank 3. The mixing chamber 302 provides sufficient space and time for the molten steel from the ladle 1 to mix and stabilize. The molten steel is temporarily retained in the mixing chamber 302, allowing non-metallic inclusions to float to the surface and be absorbed and removed by the covering agent. Step S202: The mixed and purified molten steel is smoothly and evenly distributed into the casting cavity 303 through multiple flow equalization holes 3051 on the partition structure 305; Step S202 is a key step. Through this step, the path length and shape of the molten steel flow field corresponding to each uniform flow hole 3051 can be kept basically consistent, thereby avoiding the problem of poor quality of some billets due to the difference in internal flow field in the traditional double intermediate tank structure.

[0043] Step S3: Molten steel in the casting cavity 303 is injected into the crystallizer 5 through multiple submerged entry nozzles and multiple flow paths, and a billet 10 with a shell is formed in the crystallizer 5; Cooling water flows through the crystallizer 5, where the high-temperature molten steel is rapidly cooled upon contact with the copper plate, forming a billet shell of a certain thickness. During this process, a vibrating device continuously vibrates the crystallizer 5 to prevent the nascent billet shell from sticking to the copper plate.

[0044] Step S4: The billet 10 with the shell is conveyed to the sector section 7, and the clamping rollers on both sides of the sector section 7 support and cool the billet 10. Among them, the clamping rollers arranged in the fan-shaped section 7 provide mechanical support for the billet shell to prevent it from bulging and deforming under the action of internal static pressure of molten steel; in addition, since multiple nozzles are arranged in the fan-shaped section 7, they are used to spray atomized water onto the surface of the billet 10 for powerful secondary cooling. During this process, the thickness of the billet shell continuously increases until the billet 10 is completely solidified.

[0045] Step S5: The completely solidified billet 10 is conveyed to the fixed section 8, and the clamping rollers on both sides of the fixed section 8 guide and cool the billet 10 again. Step S6: The billet 10 is conveyed to the straightening machine 9 to straighten the billet 10 so that it meets the preset flatness requirements; Step S7: The straightened billet is cut to a fixed length using billet-out equipment (such as a flame cutting machine), and then transported off the production line to complete the production of large square billets or round billets.

[0046] In an optional embodiment of the present invention, in step S3, the flow rate of molten steel at multiple molten steel outlets 307 on the casting cavity 303 is independently controlled by multiple stoppers 306, and the temperature of each flow path is continuously monitored in real time by temperature measuring elements, thereby obtaining the molten steel temperature of each flow path. This can provide real-time molten steel temperature for the secondary cooling calculation model of each flow path (i.e., the preset calculation model for calculating and controlling the cooling water volume and distribution of the secondary cooling zone (fan-shaped segment 7), providing basic data support for process calculation, improving the accuracy of temperature model calculation in steel production, and thus ensuring the quality of the casting billet 10 of large square billets or round billets.

[0047] The multi-flow continuous casting control method of the present invention can realize the production of irregularly shaped continuous casting billets (such as large square billets or round billets), and can provide the required irregularly shaped billets for steel rolling.

[0048] The multi-strand continuous casting control method of the present invention has the same features and advantages as the multi-strand continuous casting machine described above, and will not be repeated here.

[0049] It should be noted that in the description of this application, the terms "first," "second," etc., are used only for descriptive purposes and to distinguish similar objects; there is no order between them, nor should they be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "multiple" means two or more.

[0050] The various embodiments described in this specification are presented in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0051] The above are merely a few embodiments of the present invention. Although the embodiments disclosed in the present invention are as described above, the content is only for the purpose of facilitating understanding of the present invention and is not intended to limit the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention should fall within the scope of protection of the present invention.

Claims

1. A multiple strand continuous caster characterized by, The multi-stream continuous casting machine comprises: a ladle; at least two tundishes, the ladle being connected with the long-water interfaces of the at least two tundishes through long ladle shroud respectively; the inside of the tundish has a partition structure, which divides the inside of the tundish into a mixing cavity and a pouring cavity, the mixing cavity being communicated with the long-water interface, the partition structure having a plurality of flow uniformizing holes, so that the molten steel in the mixing cavity is branched into the pouring cavity, the pouring cavity having a plurality of molten steel outlets which are spaced and uniformly distributed on the wall surface opposite to the partition structure, and the plurality of molten steel outlets being connected with a plurality of submerged nozzles respectively; a crystallizer, the at least two tundishes being connected with the crystallizer through the plurality of submerged nozzles respectively.

2. The multiple-strand continuous caster of claim 1 wherein, The mixing cavity is a long strip-shaped cavity, and the long-water interface and the partition structure are located at two ends of the mixing cavity in the length direction respectively.

3. A multiple-strand continuous caster as claimed in claim 1 or 2, characterised in that, The pouring cavity is communicated with the mixing cavity through a necking section on the pouring cavity, the partition structure is arranged on the necking section, and the cavity of the pouring cavity is expanded to two sides relative to the necking section respectively, so that the pouring cavity forms a flat wall surface on the side opposite to the partition structure, and the plurality of molten steel outlets are spaced and uniformly distributed along the length direction of the wall surface.

4. The multiple-strand continuous caster of claim 3 wherein, The partition structure comprises a first partition plate and two second partition plates located on two sides of the first partition plate respectively, the plurality of flow uniformizing holes are located on the two second partition plates respectively, two opposite edges of the first partition plate are connected with one side edge of the two second partition plates respectively, and the other opposite side edges of the two second partition plates are connected with the inner wall of the tundish. The included angle between the plate surface of the first partition plate and the plate surface of the second partition plate is obtuse, the first partition plate protrudes into the mixing cavity in the installed state of the partition structure, and the plate surfaces of the two second partition plates are respectively directed to two sides of the partition structure, so as to uniformly branch the molten steel to the pouring cavity.

5. The multiple-strand continuous caster of claim 1 wherein, Temperature measuring points are arranged at the positions of the pouring cavity and the plurality of molten steel outlets respectively, and temperature measuring elements are arranged at the temperature measuring points.

6. The multiple-strand continuous caster of claim 5 wherein, Plug rods are arranged at the plurality of molten steel outlets respectively.

7. The multiple-strand continuous caster of claim 1 wherein, The multi-stream continuous casting machine further comprises a plurality of withdrawal straightening machines, and a fan-shaped section and a fixed section are sequentially connected between the outlet of the crystallizer and the withdrawal straightening machines, and the two sides of the fan-shaped section and the fixed section have a plurality of clamping rollers respectively.

8. A multi-strand continuous casting control method which is implemented by the multi-strand continuous casting machine according to any one of claims 1 to 7, characterized by, The multi-stream continuous casting control method comprises the following steps: Step S1: molten steel is filled into a ladle; Step S2: the molten steel in the ladle is injected into two tundishes through two long ladle shrouds respectively; Step S201: the molten steel enters the mixing cavity through the long-water interface on the tundish, and the molten steel is temporarily retained in the mixing cavity and the floating inclusions are removed; Step S202: the mixed and purified molten steel is uniformly branched into the pouring cavity through the plurality of flow uniformizing holes on the partition structure; Step S3: the molten steel in the pouring cavity is injected into the crystallizer through the plurality of submerged nozzles in multiple flow paths, and a casting blank with a shell is formed in the crystallizer.

9. The multi-strand continuous casting control method as claimed in claim 8, characterized by, After the step S3, the following steps are further included: Step S4: the casting blank with the shell is transported to a fan-shaped section, and a pair of clamping rollers on both sides of the fan-shaped section support and cool the casting blank; Step S5: the completely solidified casting blank is transported to a fixed section, and a pair of clamping rollers on both sides of the fixed section guide and re-cool the casting blank; Step S6: the casting blank is transported to a straightening machine to straighten the casting blank; Step S7: the straightened casting blank is cut and discharged by an ejection device, and the production of a bloom or a round billet is completed.

10. The multi-strand continuous casting control method as claimed in claim 8, characterized by, In the step S3, the flow of molten steel of the multiple molten steel outlets on the pouring cavity is independently controlled by multiple stoppers.

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