Downhole brick for casting special steel

Abstract

The utility model relates to a lower nozzle brick for casting special steel, which comprises a first nozzle brick body and a second nozzle brick body, the first nozzle brick body is coaxially connected to an upper port of the second nozzle brick body, a plurality of air holes are radially arranged in the side wall of the second nozzle brick body along the axial direction, the air holes form a radial hole group, and the radial hole group is communicated with the first nozzle brick body. The inner end of the air hole penetrates into the steel flowing hole, the outer side face of the second nozzle brick body is connected with an air inlet connector, and the inner end of the air inlet connector communicates with the outer end of the air hole. A plurality of radial hole sets are evenly distributed in the second nozzle brick body, an annular cavity is formed in the second nozzle brick body, the outer ends of the air holes distributed in the inner circumference of the second nozzle brick body are all communicated with the annular cavity, and the air inlet connector pipe is communicated with all the air holes through the annular cavity. The lower nozzle brick can avoid the phenomenon that molten steel is prone to secondary oxidation, the requirement for special steel types with the low requirement for the casting oxygen content is met, and the casting quality of steel is effectively guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of steelmaking refractory materials, and in particular to a drain outlet brick for casting special steel. Background Technology

[0002] The drain nozzle brick is a key refractory material component at the bottom of the steel ladle, used to control the flow rate and velocity of molten steel. Its core function is to stably guide the flow of molten steel in high-temperature environments, ensuring the safety and efficiency of the casting process. Drain nozzle bricks are widely used in the sliding gate systems of ladles and tundishes, regulating the molten steel flow rate through the sliding of upper and lower slide plates. As a channel for steel flow, the drain nozzle brick connects with the long gate of the ladle to protect the steel during casting and prevent secondary oxidation. Traditional drain nozzles are formed in two ways: one is machine-pressed, where the drain nozzle brick blank is dried and then assembled with the drain nozzle shell; the other is cast-in-place with the shell attached. Neither of these methods effectively prevents secondary oxidation of the molten steel during casting and cannot meet the requirements for casting special steel grades with low oxygen content. Utility Model Content

[0003] To solve the above problems, this utility model proposes a drain outlet brick for casting special steel.

[0004] The technical solution of this utility model is: a drain brick for casting special steel, comprising a first drain brick body and a second drain brick body. The first drain brick body is coaxially connected to the upper port of the second drain brick body. Both the first and second drain brick bodies are provided with steel flow holes inside. The side wall of the second drain brick body is provided with a plurality of vent holes radially along the axial direction. The vent holes are round holes. These vent holes form a radial hole group. The inner end of the vent holes extends into the steel flow holes. An air inlet connector is connected to the outer side of the second drain brick body. Inert air is introduced into each vent hole through the air inlet connector. The inner end of the air inlet connector is connected to the outer end of the vent hole.

[0005] Preferably, the second sprue brick has a plurality of radial hole groups evenly distributed inside, and an annular chamber is provided inside the second sprue brick. The cross-section of the annular chamber is square. The outer ends of the vent holes distributed around the circumference of the second sprue brick are all connected to the annular chamber. The air inlet connector pipe is connected to each vent hole through the annular chamber.

[0006] Preferably, the first sprue brick is a machine-pressed brick, and the second sprue brick is a cast-molded brick. The machine-pressed brick needs to be dried before the second sprue brick is cast.

[0007] Preferably, the bottom surface of the second sprue brick has an annular protrusion with an isosceles trapezoidal cross-section in the middle, and the upper surface of the first sprue brick has an annular groove in the middle that corresponds to the position of the annular protrusion and matches its size, and the annular protrusion fits into the annular groove.

[0008] Preferably, the outer surfaces of the first and second sprue bricks are fitted with steel shells. The upper end of the steel shell is spaced apart from the upper surface of the second sprue brick, and the lower end is spaced apart from the bottom surface of the first sprue brick. The steel shell and the bricks are fixedly connected by fire clay.

[0009] Preferably, the steel shell has an annular rib protruding into its inner side in the middle. The annular rib is embedded in the fire clay. The cross-section of the annular rib is an arc-shaped groove. The annular rib is formed by rolling.

[0010] The beneficial technical effects of this utility model are as follows: the upper part of the drain outlet brick is evenly distributed with a ring of vent holes in a radial pattern. The vent holes and the air inlet are connected through an annular chamber. After the inert gas enters the annular chamber, it can be evenly distributed to each vent hole. When the molten steel passes through the steel flow hole, the inert gas coming out of the vent holes can completely cover the molten steel from the circumference, avoiding the phenomenon of secondary oxidation of the molten steel. This meets the requirements of casting special steel grades with low oxygen content and effectively ensures the casting quality of the steel. Attached Figure Description

[0011] Figure 1 This is a top view of the structure of this utility model;

[0012] Figure 2 yes Figure 1 A schematic diagram of the AA-direction cross-section structure;

[0013] Figure 3 yes Figure 2 Schematic diagram of the BB-direction cross-section structure.

[0014] In the figure, 1. Second sprue brick, 11. Vent hole, 12. Annular chamber, 13. Annular protrusion, 2. First sprue brick, 21. Annular groove, 3. Steel flow hole, 4. Air inlet connector, 5. Steel shell, 51. Annular rib, 6. Fire clay. Detailed Implementation

[0015] Example 1, see appendix Figure 1-3 A type of drain brick for casting special steel includes a first drain brick body 2 and a second drain brick body 1. The first drain brick body 2 is coaxially connected to the upper port of the second drain brick body 1. The side wall of the second drain brick body 1 is provided with a plurality of vent holes 11 radially along the axial direction. The spacing between the ports of each vent hole 11 is the same to ensure the uniform distribution of gas in the steel flow hole 3. These vent holes 11 form a radial hole group, and each group usually arranges four vent holes. The inner end of the vent hole 11 extends into the steel flow hole 3. An air inlet connector 4 is connected to the outer side of the second drain brick body 1. The inner end of the air inlet connector communicates with the outer end of the vent hole 11. The vent hole 11 forms an inclined airflow channel inside the drain brick.

[0016] The second water inlet brick 1 has several radial hole groups evenly distributed inside, and an annular chamber 12 is provided inside the second water inlet brick 1. The outer ends of the vent holes 11 distributed around the circumference of the second water inlet brick 1 are all connected to the annular chamber 12. The air inlet connector 4 is connected to each vent hole 11 through the annular chamber 12. The air inlet connector 4 is connected to the air source through the pipe. Inert gas enters the annular chamber 12 from the air inlet connector 4 and is then distributed from the annular chamber 12 to each vent hole 11.

[0017] Steel shells 5 are fitted onto the outer surfaces of the first sprue brick 2 and the second sprue brick 1. The steel shells 5 and the bricks are fixedly connected by fire putty 6. The fire putty is evenly filled into the gap between the steel shells 5 and the bricks. After drying, the two are firmly bonded and fixed into one piece.

[0018] The steel shell 5 has an annular rib 51 protruding into its inner side in the middle. The annular rib 51 is embedded in the fire clay 6, which can improve the bonding strength between the steel shell 5 and the outer side of the drain brick, and ensure the stability of the two being installed together.

[0019] In this embodiment, when the drain outlet brick is used, inert gas enters the annular chamber 12 inside the drain outlet brick through the air inlet connector 4 and quickly fills the annular chamber 12. Then, it is evenly distributed from the annular chamber 12 into each vent hole 11 and sprayed into the steel flow hole 3 from the inner end of the vent hole 11. When the molten steel passes through the steel flow hole 3, the inert gas coming out of the vent hole 11 can cover the molten steel from the circumference and spray it. The molten steel is not prone to secondary oxidation and will not cause a large amount of oxide impurities to block the drain outlet due to oxidation, thus ensuring the continuous pouring of molten steel and ensuring the pouring quality of the steel.

[0020] Example 2, see appendix Figure 1-3 This embodiment is basically the same as Embodiment 1, and the similarities will not be repeated. The difference is that the first gate brick 2 is a machine-pressed brick, and the second gate brick 1 is a cast brick. The gate brick is made by a combination of extrusion and casting, so that it has the function of preventing secondary oxidation of molten steel.

[0021] The second sprue brick 1 has an annular protrusion 13 with an isosceles trapezoidal cross-section in the middle of its bottom surface. The first sprue brick 2 has an annular groove 21 in the middle of its upper surface that corresponds to the position of the annular protrusion 13 and matches its size. The annular protrusion 13 and the annular groove 21 form a tenon and mortise structure between the second sprue brick 1 and the first sprue brick 2, so that the second sprue brick 1 can interlock with each other after being poured into the upper end of the first sprue brick 2, thereby improving the connection strength between the two bricks.

[0022] The manufacturing process of the outlet brick in this embodiment is as follows: the first outlet brick body 2 is made using a molding press. After the first outlet brick body 2 is dried, a steel shell 5 with an air inlet connector 4 is assembled. After the steel shell 5 is assembled and dried, the second outlet brick body 1 with vent holes 11 is poured. During the pouring process, a burn-off strip is placed between the outlet core and the mold shell. The air inlet is sealed with a burn-off sheet to prevent the mud from entering the vent holes 11 during the pouring process. After the second outlet brick body 1 is poured and naturally dried, the outlet brick finished product is obtained. During the drying process, the pre-embedded burn-off strip and burn-off sheet completely evaporate, forming the vent holes 11.

Claims

1. A type of cast special steel drain outlet brick, characterized in that: It includes a first sprue brick and a second sprue brick. The first sprue brick is coaxially connected to the upper port of the second sprue brick. The side wall of the second sprue brick has a number of vent holes arranged radially along the axial direction. These vent holes form a radial hole group. The inner end of the vent holes extends into the steel flow hole. The outer side of the second sprue brick is connected to an air inlet connector. The inner end of the air inlet connector is connected to the outer end of the vent hole.

2. The drain outlet brick for casting special steel according to claim 1, characterized in that: The second water inlet brick has a number of radial hole groups evenly distributed inside, and an annular cavity is provided inside the second water inlet brick. The outer ends of the vent holes distributed around the circumference of the second water inlet brick are all connected to the annular cavity. The air inlet connector pipe is connected to each vent hole through the annular cavity.

3. The drain outlet brick for casting special steel according to claim 1, characterized in that: The first sprue brick is a machine-pressed brick, and the second sprue brick is a cast brick.

4. The drain outlet brick for casting special steel according to claim 3, characterized in that: The second sprue brick has an annular protrusion with an isosceles trapezoidal cross-section in the middle of its bottom surface, and the first sprue brick has an annular groove in the middle of its upper surface that corresponds to the position of the annular protrusion and matches its size.

5. The drain outlet brick for casting special steel according to claim 1, characterized in that: The outer surfaces of the first and second sprue bricks are fitted with steel shells, and the steel shells and bricks are fixedly connected by fire clay.

6. The drain outlet brick for casting special steel according to claim 5, characterized in that: The steel shell has an annular rib protruding inward from the middle, and the annular rib is embedded in the fire clay.

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