Automatic flow-down tundish for starting casting of continuous casting machine

Abstract

The utility model relates to a continuous casting machine automatic flow -down tundish of casting -on, including the tundish body, and the seat brick of a plurality of upper water gaps of tundish body bottom, the upper water gap is fixed with the casting -on cup, the casting -on cup is inside and is passed along the vertical and is communicated with the inner hole of upper water gap's flow -steel hole, the upper end of casting -on cup is no less than the tundish bottom, and along the molten steel flow direction, the upper end height of any casting -on cup is greater than or equal to its upstream side adjacent casting -on cup upper end height. The utility model discloses the casting -on cup is set up on the upper water gap, and the casting -on cup top is higher than the tundish bottom, along the molten steel flow direction, the upper end surface of the casting -on cup corresponding to the flow -steel hole is set gradually from low to high, makes the molten steel flow out gradually from the flow -steel hole along the flow direction, has improved the tundish casting -on success rate, effectively solved the sizing slider tundish casting -on self -opening rate low, the problem of the tundish casting -on personnel tension, the high production accident rate of multiple flow continuous casting machine.

Description

Technical Field

[0001] This utility model relates to the field of tundish technology for continuous casting in iron and steel metallurgy, and in particular to an automatic downstream tundish for continuous casting machine start-up. Background Technology

[0002] Currently, there are three main types of tundish flow control: sizing slider, stopper rod, and slide plate. Stopper rod and slide plate tundishes can achieve automatic flow control during tundish start-up by controlling the stroke of the stopper rod and slide plate (with exhaust heating at the top nozzle). However, sizing slider tundishes, which control flow by adding guiding sand or calcium silicate blocks to the top nozzle and slide plate cavity, have a low self-opening rate. This is mainly because the guiding sand added to the top nozzle and slide plate cavity needs to be added before tundish baking. After prolonged high-temperature flame baking, the guiding sand easily sinters and clumps, preventing the tundish from opening automatically during start-up. Similarly, the calcium silicate blocks added to the top nozzle and slide plate cavity are affected by the quality and quantity of the calcium silicate blocks, as well as the molten steel temperature, preventing the tundish from opening automatically during start-up.

[0003] In addition, the current trend of small billet continuous casting machines is to adopt a multi-flow design with more than 8 flowers. The more flowers the continuous casting machine has in the tundish, the more personnel are needed to start the tundish. When the tundish does not open automatically, a burn-in operation is required, which leads to a shortage of tundish start-up personnel and a high production accident rate.

[0004] If the sizing slider tundish is used directly without adding diluents such as diluent sand or calcium silicate blocks, the tundish will contain a lot of impurities and refractory material, which can easily clog the inlet and prevent the slider from opening automatically. The tundish bottom temperature will be low, resulting in low molten steel temperature, causing issues such as flow dispersion and frozen spots that prevent automatic opening during casting. Chinese patent document CN114453577A (202210086990.X) describes a quick-change sizing tundish diluent rod and a diluent rod casting process. The diluent rod includes a packaging tube, which comprises a first filling section and a second filling section. The first filling section is filled with ferrosilicon alloy, and the second filling section is filled with diluent sand. The process of using a guide rod for initial casting includes steps S1, baking the tundish without adding any material to the sizing nozzle, and simultaneously baking the tundish with a negative pressure baking device installed under the slide block for 3-6 hours until the temperature inside the tundish reaches 1000℃-1200℃; S2, installing the guide rod by inserting it into the slide block through-hole and the tundish sizing nozzle channel from the lower end of the slide block, ensuring the first filling section is above the second filling section; S3, sealing the lower end through-hole of the slide block with a plug cone; and S4, injecting molten steel into the tundish. When the molten steel level is not lower than two-thirds of the working layer height of the tundish, the plug cone is removed, and initial casting begins. The above application has the following drawbacks: Adding ferrosilicon alloy and guide sand to the tundish nozzle causes the ferrosilicon alloy and guide sand to melt and agglomerate in direct contact with the flame after prolonged baking, resulting in a generally low actual initial casting rate; the initial casting rate is significantly affected by the amount added, the size of the ferrosilicon alloy pieces, and the properties of the guide sand. Methods for opening the pouring tube with a guide rod: During the tundish drying process, debris inside the tundish can easily enter the tundish top nozzle, clogging the channel and making it difficult to insert the guide rod; the outer shell of the guide rod is made of steel, which can easily solidify and stick when the molten steel is at a low temperature, causing it not to open automatically; other high-temperature resistant materials are expensive to use; after it does not open automatically, it is extremely difficult to manually burn the nozzle to open the pouring tube. Utility Model Content

[0005] This invention addresses the shortcomings of existing technologies by providing an automatic tundish for continuous casting machine start-up. By setting start-up cups of different heights, it significantly improves the success rate of tundish start-up.

[0006] This utility model is achieved through the following technical solution: providing an automatic downstream tundish for continuous casting machine, including a ladle body, and a plurality of water inlets and seat bricks disposed at the bottom of the ladle body. An opening cup is fixed on the water inlet, and a steel flow hole is opened in the opening cup, which is vertically penetrating and communicating with the inner hole of the water inlet. The upper end of the opening cup is not lower than the bottom of the ladle, and along the direction of steel flow, the upper end height of any opening cup is greater than or equal to the upper end height of the adjacent opening cup on its upstream side.

[0007] This solution controls the height of molten steel flow by setting up opening cups, so that the molten steel flows out sequentially from the flow holes of each opening cup during the process of flowing in the ladle, thereby improving the success rate of tundish opening.

[0008] As an optimization, the steel flow hole is fitted downwards onto the outer wall of the water inlet, and the wall of the steel flow hole is sealed to the water inlet. This optimized solution allows the pouring cup to be fitted onto the water inlet through the steel flow hole, making the installation of the pouring cup more convenient and facilitating the sealing between the steel flow hole and the water inlet.

[0009] As an optimization, the outer wall of the inlet is tapered, wider at the top and narrower at the bottom. The diameter of the steel flow hole is larger than the upper outer diameter of the inlet and smaller than the lower outer diameter. This optimized design, by making the outer wall of the inlet tapered, facilitates the sealing between the steel flow hole and the outer wall of the inlet. Furthermore, the greater the downward pressure on the pouring cup, the better the sealing effect between the steel flow hole and the outer wall of the inlet.

[0010] As an optimization, five pouring cups are arranged sequentially and at intervals along the direction of molten steel flow. These five pouring cups are designated as Pouring Cup I, Pouring Cup II, Pouring Cup III, Pouring Cup IV, and Pouring Cup V. The upper end of Pouring Cup I is higher than the bottom of the ladle. The upper ends of Pouring Cups II and III are equal in height and both greater than the upper end of Pouring Cup I. The upper ends of Pouring Cups IV and V are equal in height and both greater than the upper end of Pouring Cup III. This optimized scheme, with five pouring cups, ensures a flow rate of 10 streams when two tundishes are used simultaneously. Furthermore, by adjusting the height of each pouring cup within the same tundish, it achieves both gradual molten steel flow and ensures pouring efficiency.

[0011] As an optimization, the upper ends of pouring cups IV and V are 350mm above the bottom of the ladle, the upper ends of pouring cups II and III are 250mm above the bottom of the ladle, and the upper end of pouring cup I is 150mm above the bottom of the ladle. This optimized height setting for each pouring cup better enables the automatic pouring and downward flow of molten steel through pouring cups of different heights.

[0012] As an optimization, the outer wall of the pouring cup is tapered, wider at the top and narrower at the bottom. The lower end of the pouring cup is supported on the upper surface of the base brick and covered with a refractory material. This optimized pouring cup design offers better stability and is easier to fix.

[0013] As an optimization, the pouring cup includes a left half-cup and a right half-cup arranged laterally opposite each other. The opposite sides of the left and right half-cups are each provided with a semi-circular groove. The semi-circular grooves of the left and right half-cups engage to form the flow hole. The joints of the left and right half-cups on both sides of the flow hole are Z-shaped, and the Z-shaped joints are filled with putty. This optimized solution sets the pouring cup into a left and right half-cup structure, making manufacturing easier and facilitating high-pressure forming. This is achieved by setting the contact contours of the left and right half-cups to a Z-shape and positioning them mutually.

[0014] The beneficial effects of this utility model are as follows: by setting an opening cup above the top of the water inlet, with the top of the opening cup higher than the bottom of the tundish, and by setting the upper surfaces of the opening cups corresponding to the steel flow holes in sequence from low to high along the direction of molten steel flow, the molten steel flows out from the steel flow holes in sequence along the flow direction, which improves the success rate of tundish opening and effectively solves the problems of low self-opening rate of tundish opening for sizing sliders, shortage of personnel for tundish opening in multi-strand continuous casting machines, and high production accident rate. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the intermediate liner structure of this utility model; Figure 2 This is a top view of the intermediate liner of this utility model; Figure 3 This is a schematic diagram of the pouring cup structure in this utility model; Figure 4 A top view of the pouring cup; As shown in the figure: 1. Wrench body, 2. Opening cup, 3. Inlet, 4. Sizing slider, 5. Ventilation equipment, 21. Left half cup, 22. Right half cup, 101. Pouring position, 102. Flow hole. Detailed Implementation

[0016] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0017] like Figure 1 The diagram shows an automatic downstream tundish for continuous casting, comprising a ladle body 1, and several inlet gates 3, sizing sliders 4, ventilation devices 5, and a base brick located at the bottom of the ladle body. The bottom of the ladle is also provided with refractory material. A pouring position 101 is provided inside the ladle body, and molten steel flows from the pouring position away from it. The sizing sliders 4 are located below the inlet gates 3, and the ventilation devices 5 are located below the sizing sliders 4. The inlet gates are fixed to the base brick, which matches the inlet gate 3. The base brick has a height of 150mm. The thickness of the pouring cup 2 matches that of the base brick, the inlet gates 3, and the refractory material at the bottom of the tundish. The sizing sliders 4, ventilation devices 5, the refractory material at the bottom of the ladle, and the base brick are all existing technologies and will not be described in detail. The structure of the inlet gates also adopts existing technology, with each inlet gate arranged sequentially at intervals along the direction of molten steel flow.

[0018] In this embodiment, a casting cup 2 is fixed on the inlet 3. The casting cup 2 has a vertically penetrating flow hole 102 that communicates with the inner hole of the inlet. The flow hole 102 extends from the bottom surface to the top surface of the casting cup, and the diameter of the flow hole is consistent vertically. The upper end of the casting cup is not lower than the bottom of the ladle, meaning the upper end of the casting cup is higher than or flush with the bottom of the ladle. Furthermore, along the direction of molten steel flow, the height of the upper end of any casting cup is greater than or equal to the height of the upper end of its adjacent upstream casting cup. Preferably, in this embodiment, the upper end of each casting cup is higher than the bottom of the ladle.

[0019] In this embodiment, the outer wall of the inlet is tapered, wider at the top and narrower at the bottom. The diameter of the steel flow hole is larger than the outer diameter of the upper end of the inlet and smaller than the outer diameter of the lower end. The steel flow hole is fitted downwards onto the upper end of the outer wall of the inlet, and the hole wall is sealed to the inlet.

[0020] Five pouring cups are arranged at intervals along the direction of molten steel flow. The five pouring cups are pouring cup I, pouring cup II, pouring cup III, pouring cup IV, and pouring cup V. The upper end of pouring cup I is higher than the bottom of the ladle. The upper ends of pouring cups II and III are equal in height and both are greater than the upper end of pouring cup I. The upper ends of pouring cups IV and V are equal in height and both are greater than the upper end of pouring cup III.

[0021] The height of pouring cups IV and V is 450mm, and the top of pouring cups IV and V is 350mm higher than the bottom of the ladle; the height of pouring cups II and III is 350mm, and the top of pouring cups II and III is 250mm higher than the bottom of the ladle; the height of pouring cup I is 250mm, and the top of pouring cup I is 150mm higher than the bottom of the ladle.

[0022] The outer wall of the pouring cup is a cone shape that is larger at the top and smaller at the bottom. The lower end of the pouring cup is supported on the upper surface of the base brick and is covered by a bottom refractory material with a thickness of 250mm.

[0023] For ease of manufacturing, the pouring cup in this embodiment includes a left half-cup 21 and a right half-cup 22 arranged laterally opposite each other, which are joined together to form a platform-like structure. Semicircular grooves are provided on the opposite sides of the left and right half-cups, and these grooves interlock to form the flow hole. The joints between the left and right half-cups on both sides of the flow hole are Z-shaped, and the Z-shaped joints are filled with putty. The pouring cup 2 in this embodiment is formed by pressing a mixture of bauxite, magnesia, and graphite, followed by low-temperature baking.

[0024] To meet the requirement of 10 tundish flow rates in a continuous casting machine, two tundishes can be set up for simultaneous casting. The two tundishes are symmetrically arranged, with their casting positions located at adjacent ends. The automatic flow-down method during operation includes the following steps: S1. No diversion sand is added to the sizing slider 4. The intermediate ladle is baked. 0.5-2 hours before the baking is stopped, the sizing slider 4 is baked by exhaust fan 5. The baking temperature of the sizing slider 4 is above 300℃.

[0025] S2. After the intermediate tundish stops baking, move it to the pouring position and wait for pouring to begin.

[0026] S3. Ladle opening and pouring: Molten steel is poured into the tundish and flows down automatically through the opening cups 2 at different heights.

[0027] Specifically, when the liquid level in the tundish rises to more than 150mm, the pouring cups I of both tundishes automatically begin pouring.

[0028] When the liquid level in the tundish rises to above 250mm, the pouring cups II and III of both tundishes automatically begin pouring.

[0029] When the liquid level in the tundish rises to above 350mm, the pouring cups IV and V of both tundishes automatically begin pouring.

[0030] This invention eliminates the need for guiding sand within the sizing slider. Before casting, an exhaust system is used to heat the upper nozzle and slider, ensuring automatic flow during tundish pouring. An opening cup is positioned above the upper nozzle, with its top higher than the tundish bottom. These opening cups are arranged sequentially from low to high along the steel flow direction, corresponding to the flow holes, allowing molten steel to flow out sequentially from the flow holes, thus improving the success rate of tundish pouring. This effectively solves the problems of low self-opening rates due to guiding sand and calcium silicate blocks in the sizing slider tundish, as well as the shortage of personnel and high accident rates during tundish pouring in multi-strand continuous casting machines.

[0031] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. An automatic tundish for continuous casting machine, comprising a ladle body (1), and a plurality of inlet nozzles (3) and seat bricks disposed at the bottom of the ladle body, characterized in that: The upper water inlet is fixedly provided with a pouring cup (2), and the pouring cup (2) is provided with a steel flow hole (102) that runs vertically through and communicates with the inner hole of the upper water inlet. The upper end of the pouring cup is not lower than the bottom of the ladle, and along the direction of steel flow, the height of the upper end of any pouring cup is greater than or equal to the height of the upper end of the adjacent pouring cup on its upstream side.

2. The automatic tundish for continuous casting machine start-up as described in claim 1, characterized in that: The steel flow hole is fitted downwards onto the outer wall of the water inlet, and the wall of the steel flow hole is sealed to the water inlet.

3. The automatic tundish for continuous casting machine start-up as described in claim 2, characterized in that: The outer wall of the inlet is a cone shape, wider at the top and narrower at the bottom. The diameter of the steel flow hole is larger than the outer diameter of the upper end of the inlet and smaller than the outer diameter of the lower end of the inlet.

4. The automatic tundish for continuous casting machine start-up as described in claim 1, characterized in that: Five pouring cups are arranged at intervals along the direction of molten steel flow. The five pouring cups are pouring cup I, pouring cup II, pouring cup III, pouring cup IV, and pouring cup V. The upper end of pouring cup I is higher than the bottom of the ladle. The upper ends of pouring cups II and III are equal in height and both are greater than the upper end of pouring cup I. The upper ends of pouring cups IV and V are equal in height and both are greater than the upper end of pouring cup III.

5. The automatic tundish for continuous casting machine start-up as described in claim 4, characterized in that: The upper ends of pouring cups IV and V are 350mm above the bottom of the ladle, the upper ends of pouring cups II and III are 250mm above the bottom of the ladle, and the upper end of pouring cup I is 150mm above the bottom of the ladle.

6. The automatic tundish for continuous casting machine start-up as described in claim 1, characterized in that: The outer wall of the pouring cup is a cone shape that is larger at the top and smaller at the bottom. The lower end of the pouring cup is supported on the upper surface of the base brick and is covered by a bottom refractory material.

7. The automatic tundish for continuous casting machine start-up as described in claim 1, characterized in that: The pouring cup includes a left half cup (21) and a right half cup (22) arranged opposite each other in the horizontal direction. The left half cup and the right half cup are respectively provided with semi-circular grooves on their opposite sides. The semi-circular grooves of the left half cup and the right half cup are engaged to form the steel flow hole. The joints of the left half cup and the right half cup on both sides of the steel flow hole are Z-shaped and filled with putty.

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