Masonry method of refined steel ladle structure

Abstract

The invention discloses a masonry method of a refined steel ladle structure, and relates to the technical field of steel-making equipment production, a steel ladle is provided with a steel ladle bottom structure and a steel ladle wall structure, the steel ladle bottom structure comprises a nozzle seating brick and an air brick, a castable is poured around the nozzle seating brick and the air brick to form a castable layer, and the castable layer is provided with an air inlet and an air outlet. The castable layers comprise a ladle bottom permanent castable layer and a ladle bottom working castable layer from bottom to top; a refining steel ladle nozzle cap is sleeved on the nozzle brick cup, the bottom of the refining steel ladle nozzle cap is tightly attached to the ladle bottom permanent castable layer on the periphery of the nozzle brick cup, and castable is poured on the outer side face of a boss at the bottom of the refining steel ladle nozzle cap and the top of the boss to form a ladle bottom working castable layer. Compared with the prior art, the steel ladle bottom structure has the advantages that molten steel residues are effectively reduced, and slag entrapment in the molten steel pouring process can be prevented at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of steelmaking equipment production, in particular to a masonry method for a refined steel ladle structure. Background Art

[0002] With the increase in high-grade special steel varieties, especially the sharp increase in demand for clean steel, aluminum-killed steel and silicon steel, the quality requirements for molten steel are getting higher and higher, which significantly increases the performance and masonry structure requirements for the working lining refractory materials of the refined steel ladle. In the continuous casting process, the molten steel in the refined steel ladle passes through the nozzle seat brick at the bottom of the ladle - the upper nozzle - the slide - the lower nozzle, and then enters the continuous casting machine. After the molten steel in the ladle is poured, there is often too much residual steel and steel slag at the bottom, which can generally reach about 1 to 10 tons, affecting the overall molten steel recovery rate. On the one hand, the steel tapping from the converter scours the impact area of ​​the bottom working layer of the ladle, causing pits on the upper surface of the bottom working layer. During the pouring process, the molten steel in the pits is difficult to flow out; on the other hand, at the end of the ladle pouring, when the molten steel level drops to a certain height, the molten steel generates a vortex due to the Coriolis force caused by the rotation of the earth, the circulation induced by the uneven flow field, and the potential energy of the fluid itself during the outflow process. The steel flow is swirled, causing slag. Considering the requirements for molten steel quality, the water inlet is closed through the control of the slag detection system, so that the molten steel remains in the ladle. These two aspects mainly affect the amount of residual molten steel in the ladle. In recent years, with the cost and energy-saving considerations of steel mills, the requirements for increasing the molten steel recovery rate and reducing the waste of molten steel without affecting the quality of molten steel are getting higher and higher. At present, the ladles of steel mills generally adopt flat bottoms. Since the residual molten steel and the amount of slag roll are related to the masonry structure on the upper surface of the working layer of the ladle bottom, some enterprises have improved the ladle bottom structure. For example, Chinese patent CN202220872149.9 involves a ladle bottom structure that effectively reduces the residual amount of molten steel in the ladle. In the impact zone at the center of the ladle bottom, a cast prefabricated plate with good corrosion resistance is used to replace the on-site overall casting construction method, which effectively enhances the corrosion and scouring resistance of the central part of the ladle bottom, avoids the appearance of pits as much as possible, and thus reduces the residual amount of molten steel in the ladle. However, at the interface between the cast prefabricated block and the ladle bottom castable, due to repeated alternation of hot and cold during long-term service, through cracks are easily formed, resulting in cracking and abnormal peeling of the prefabricated block in the impact zone. At the same time, the presence of through cracks is likely to cause pits in the working layer, affecting the casting surplus of the ladle, posing a safety risk. For example, in the ladle bottom structure involved in Chinese patent CN202120265685.8, the top surface of the impact brick is higher than the top surface of the nozzle brick, and a guide groove is provided in the castable layer between the impact brick and the nozzle brick. By pre-setting the slag control area and the guide groove, the structure of the upper surface of the ladle bottom working lining is optimized to improve the flow field of the molten steel at the bottom of the ladle and reduce the casting residue of the molten steel, but no blocking measures are taken to prevent the casting residue slag from flowing into the nozzle. Summary of the invention

[0003] The purpose of the present invention is to provide a masonry method for a refining ladle structure, which can solve the problem of molten steel residue at the bottom of the existing ladle.

[0004] In order to solve the above problems, the technical solution adopted by the present invention is: it has a ladle bottom structure and a ladle wall structure, the ladle bottom structure includes a nozzle seat brick and a breathable brick, and castables are poured around the nozzle seat brick and the breathable brick to form a castable layer, and the castable layers are respectively a permanent castable layer for the bottom of the ladle and a working castable layer for the bottom of the ladle from bottom to top; a refined steel ladle nozzle cap is sleeved on the nozzle seat brick, and the refined steel ladle nozzle cap includes a cap body, which is a hollow structure, and its upper and lower parts are open. The shape of the cap body is a rectangular parallelepiped or a cube or a cylinder or a prism, and the side walls of the cap body are symmetrically inclined and provided with backflow holes, and the bottom side of the cap body is provided with outwardly extending During the construction of the boss, the nozzle cap of the refined steel ladle is placed on the nozzle seat brick, and the bottom end of the nozzle cap of the refined steel ladle is pressed onto the permanent casting material layer of the bottom of the ladle around the nozzle seat brick, and then the casting material is poured onto the boss of the nozzle cap of the refined steel ladle and the outside of the boss, and the casting material is poured to 0 to 30 mm from the lower edge of the outer side of the diversion hole of the nozzle cap of the refined steel ladle, where the casting material is connected with the working casting material layer of the bottom of the ladle and forms the working casting material layer of the bottom of the ladle to be concave toward the nozzle seat brick in a slope shape; a casting material layer of the bottom impact zone is poured in the middle of the bottom structure of the steel ladle, and the upper surface of the casting material layer of the bottom impact zone is higher than the upper surface of the working casting material layer of the bottom of the ladle.

[0005] In the above technical solution, a more specific technical solution may also be: the radius of the flow-conducting hole of the cap body is 30 mm to 70 mm.

[0006] In some possible implementation schemes, the flow-conducting holes are axially symmetrically arranged on the side wall of the cap body, and the number of the flow-conducting holes is 2 to 8.

[0007] In some possible implementation schemes, the cap body is a prefabricated part made of refractory material.

[0008] In some possible implementation schemes, the refractory material used for the cap body is corundum spinel, aluminum magnesium or corundum.

[0009] In some possible embodiments, the ladle wall comprises, from the outside to the inside, a steel shell, a permanent castable layer for the ladle wall, slag line bricks for the ladle wall working layer and precast blocks for the ladle wall working layer in sequence; the permanent castable layer for the ladle bottom and the permanent castable layer for the ladle wall are both formed by casting high-alumina refractory castables, the precast blocks for the ladle wall working layer are formed by laying carbon-free corundum-spinel precast blocks, the slag line bricks for the ladle wall working layer are formed by laying magnesia-carbon bricks, and the working castable layer for the ladle bottom and the castable layer for the ladle impact zone are formed by casting corundum-spinel castables.

[0010] In some possible embodiments, the upper surface of the bottom working castable layer is an inclined surface, and the height difference between its highest point and the bottom working castable layer at the nozzle brick is 30 to 80 mm; the height difference between the bottom impact zone castable layer and the bottom working castable layer at the nozzle brick is 30 to 80 mm.

[0011] In some possible implementations, a gap filling castable is used to fill the gap between the nozzle seat brick and the permanent castable layer at the bottom of the package.

[0012] Due to the adoption of the above technical solution, the present invention has the following beneficial effects compared with the prior art: 1. Since the nozzle cap of the refined steel ladle is built around the nozzle seat brick, the molten steel flows out from the backflow hole of the nozzle cap, preventing slag from entering the nozzle, reducing molten steel casting surplus, improving molten steel recovery rate, and ensuring the safe operation of the ladle.

[0013] 2. A nozzle cap for a refined steel ladle is installed around the nozzle seat brick at the bottom of the refined steel ladle, and the working castable layer at the bottom of the steel ladle is sloped and recessed toward the nozzle seat brick, so that a concave area is formed at the nozzle seat brick. A castable layer for the impact zone of the ladle bottom is poured in the middle of the ladle bottom structure, and the upper surface of the castable layer for the impact zone of the ladle bottom is higher than the upper surface of the working castable layer of the ladle bottom, so that the castable layer for the impact zone of the ladle bottom forms a high convex area. Such a structure effectively reduces the residual molten steel and prevents slag rolling during the pouring of molten steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the nozzle cap of the refining ladle.

[0015] Figure 2 It is a structural schematic diagram of the refining ladle structure.

[0016] Figure 3 Yes Figure 2 AA rotated section view.

[0017] Description of the markings in the figure: Refining steel ladle nozzle cap 1, cap body 1-1, backflow hole 1-2, boss 1-3, nozzle seat brick 2, caulking castable 3, ladle bottom permanent castable layer 4, ladle bottom working castable layer 5, ladle bottom impact zone castable layer 6, air-permeable brick 7, ladle wall working layer prefabricated block 8, ladle wall working layer slag line brick 9, ladle wall permanent castable layer 10, steel shell 11. DETAILED DESCRIPTION

[0018] In order to make the above-mentioned purposes, features and advantages of the present invention easier to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. In the following description, many specific details are set forth in order to fully understand the present invention, but the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0019] In the description of the present invention, it should be understood that the terms "middle", "length", "width", "up", "down", "front", "back", "top", "bottom", "inside", "outside", "radial", "circumferential" and the like indicate the orientation or position relationship given in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the position or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0020] like Figure 1 The water inlet cap of the refined steel ladle shown in the figure can be made into a rectangular parallelepiped, a cube, a cylinder or a prism shape. In this embodiment, the water inlet cap of the refined steel ladle includes a cap body 1-1, which is a cube with a hollow structure, and is open at the top and bottom. The side wall of the cap body is symmetrically inclined with backflow holes 1-2, and the bottom side of the cap body is provided with a boss 1-3 extending outward, on which the castable is poured. The radius of the flow guide hole 1-3 of the cap body 1-1 is 30 mm to 70 mm. In this embodiment, there are 4 flow guide holes, 1-3 are axially symmetrically arranged on the four side walls of the cap body 1-1; the cap body 1-1 is a refractory prefabricated part, and the refractory material used is corundum spinel, aluminum magnesium or corundum.

[0021] like Figure 2 and Figure 3 The refining ladle structure shown in the embodiment is as follows: Figure 1The bottom of the steel ladle is lined with the refined ladle nozzle cap shown. The refined ladle structure has a ladle bottom structure and a ladle wall structure. The ladle bottom structure includes a nozzle seat brick 2 and a porous plug 7. A castable is poured around the nozzle seat brick 2 and the porous plug 7 to form a castable layer, which is, from bottom to top, the permanent bottom castable layer 4 and the working bottom castable layer 5; A refined ladle nozzle cap 1 is sleeved on the nozzle seat brick 2. In this embodiment, the height of the refined ladle nozzle cap 1 is 500 mm. The bottom of the refined ladle nozzle cap is closely placed on the permanent bottom castable layer 4 around the nozzle seat brick 2. Then, a castable is poured on the outer side surface and the top of the boss at the bottom of the refined ladle nozzle cap to form the working bottom castable layer 5. In this way, the boss 1-3 is buried under the working bottom castable layer, so that the refined ladle nozzle cap can be stably set on the nozzle seat brick 2. A caulking castable 3 is filled between the nozzle seat brick 2 and the permanent bottom castable layer 4; The working bottom castable layer 5 is recessed in a slope shape towards the nozzle seat brick 2, so that a low concave area is formed at the nozzle seat brick. In this embodiment, this low concave area is 80 mm lower than the entire ladle bottom plane; The height from the lower edge of the outer side of the flow guiding through hole 1-2 of the refined ladle nozzle cap 1 to the upper surface of the working bottom castable layer 5 outside the side wall of the cap body 1-1 is 0-30 mm; A bottom impact zone castable layer 6 is poured upwards in the middle of the ladle bottom structure. The upper surface of this bottom impact zone castable layer is higher than the upper surface of the working bottom castable layer 5, making it a high convex area. In this embodiment, this high convex area is 50 mm higher than the entire ladle bottom plane.

[0022] Since the impact zone part in this invention patent is higher than the nozzle part, the working bottom castable layer of the ladle is smoothly transitioned and in a slope shape from the impact zone to the nozzle part. At the same time, a refined ladle nozzle cap is used around the nozzle seat brick. By optimizing the structure of the upper surface of the working bottom lining and adding the refined ladle nozzle cap for slag blocking, it is very beneficial to improve the flow field of the molten steel at the bottom of the ladle, prevent the steel slag from entering the nozzle, reduce the casting residue of the molten steel, increase the yield of the molten steel, and ensure the safe operation of the ladle.

[0023] The above examples are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for building a refining ladle structure, characterized in that: The invention has a ladle bottom structure and a ladle wall structure, wherein the ladle bottom structure comprises a nozzle seat brick (2) and a gas-permeable brick (7), and castables are poured around the nozzle seat brick (2) and the gas-permeable brick (7) to form castable layers, wherein the castable layers are respectively a ladle bottom permanent castable layer (4) and a ladle bottom working castable layer (5) from bottom to top; a refined steel ladle nozzle cap (1) is sleeved on the nozzle seat brick (2), and the refined steel ladle nozzle cap comprises a cap body (1-1), which is a hollow structure with openings at the top and bottom, and has a rectangular or cube-shaped or cylindrical or prism-shaped shape, and the side walls of the cap body are symmetrically inclined and provided with backflow holes (1-2), and the side surfaces of the bottom of the cap body are provided with outwardly extending bosses (1-3). When the ladle is laid, A refined steel ladle nozzle cap (1) is placed on the nozzle seat brick (2), and the bottom end of the refined steel ladle nozzle cap is pressed onto the ladle bottom permanent castable material layer (4) around the nozzle seat brick (1). Then, the castable material is poured onto the boss of the refined steel ladle nozzle cap and the outside of the boss, and the castable material is poured to a distance of 0 to 30 mm from the lower edge of the outer side of the diversion hole (1-2) of the refined steel ladle nozzle cap (1). The castable material at this location is poured and connected with the ladle bottom working castable material layer to form the ladle bottom working castable layer (5) which is sloped and recessed toward the nozzle seat brick (2); a ladle bottom impact zone castable material layer (6) is poured in the middle of the ladle bottom structure, and the upper surface of the ladle bottom impact zone castable material layer is higher than the upper surface of the ladle bottom working castable material layer (5).

2. The method for building a refined steel ladle structure according to claim 1, characterized in that: The radius of the flow-conducting hole (1-3) of the cap body (1-1) is 30 mm to 70 mm.

3. The method for building a refined steel ladle structure according to claim 1 or 2, characterized in that: The flow-guiding holes (1-3) are axially symmetrically arranged on the side wall of the cap body (1-1), and the number of the flow-guiding holes (1-3) is 2 to 8.

4. The method for building a refined steel ladle structure according to claim 1, characterized in that: The cap body (1-1) is a prefabricated part made of refractory material.

5. The method for building a refined steel ladle structure according to claim 4, characterized in that: The refractory material used for the cap body (1-1) is corundum spinel, aluminum magnesium or corundum.

6. The method for building a refined steel ladle structure according to claim 1, characterized in that: The ladle wall comprises, from the outside to the inside, a steel shell (11), a permanent ladle wall castable layer (10), a ladle wall working layer slag line brick (9) and a ladle wall working layer prefabricated block (8), wherein the ladle bottom permanent castable layer (4) and the ladle wall permanent castable layer (10) are both formed by casting high-alumina refractory castables, the ladle wall working layer prefabricated blocks (8) are formed by laying carbon-free corundum spinel prefabricated blocks, the ladle wall working layer slag line brick (9) are formed by laying magnesia carbon bricks, and the ladle bottom working castable layer (5) and the ladle bottom impact zone castable layer (6) are formed by casting corundum spinel castables.

7. The method for building a refined steel ladle structure according to claim 6, characterized in that: The upper surface of the bottom covering working castable layer (5) is an inclined surface, and the height difference between the highest point and the bottom covering working castable layer at the nozzle brick is 30 to 80 mm; the height difference between the bottom covering impact zone castable layer and the bottom covering working castable layer at the nozzle brick is 30 to 80 mm.

8. The method for building a refined steel ladle structure according to claim 6, characterized in that: A gap filling castable (3) is used to fill between the nozzle seat brick (2) and the bottom permanent castable layer (4).

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