CN219402306U - Baking equipment at whole immersion nozzle - Google Patents
Baking equipment at whole immersion nozzle Download PDFInfo
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- CN219402306U CN219402306U CN202320361796.8U CN202320361796U CN219402306U CN 219402306 U CN219402306 U CN 219402306U CN 202320361796 U CN202320361796 U CN 202320361796U CN 219402306 U CN219402306 U CN 219402306U
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Abstract
The utility model discloses a baking device for an integral submerged nozzle, and belongs to the technical field of continuous casting. The utility model relates to a baking device for an integral immersion nozzle, which comprises a baking furnace arranged below a tundish, wherein the top of the baking furnace is provided with a baking furnace cover, a through hole for the immersion nozzle to pass through is arranged on the baking furnace cover, a horizontally arranged partition is arranged at the lower part of an inner cavity of the baking furnace, a mounting hole is arranged at a position corresponding to the through hole on the partition, the partition divides the inner cavity of the baking furnace into a baking area and a negative pressure area, the baking area is provided with a burner, and a negative pressure environment is formed inside the negative pressure area. The utility model aims to provide a baking device for an integral submerged nozzle, which can realize that the baking effect of the inner surface and the outer surface of the submerged nozzle is good, the surface temperature is uniformly distributed, the probability of continuous casting of the cold steel is greatly reduced, the casting success rate of continuous casting is improved, and the service life of the submerged nozzle is prolonged.
Description
Technical Field
The utility model belongs to the technical field of continuous casting, and particularly relates to a baking device for an integral submerged nozzle.
Background
The immersion nozzle is positioned between the tundish and the crystallizer of the continuous casting machine, so that molten steel is guided to the crystallizer from the tundish, and the immersion nozzle has the following functions: preventing secondary oxidation of molten steel, controlling the flowing state and pouring speed of molten steel, promoting floating of inclusion, and preventing casting powder and nonmetallic inclusion from being involved in molten steel. The submerged nozzle is a channel for ensuring that molten steel is smoothly cast into a crystallizer, so that the nozzle is prevented from being blocked due to excessively low temperature of the molten steel, the submerged nozzle is burst due to stress concentration caused by excessively high temperature gradient of the molten steel and the submerged nozzle, the nozzle is required to be ensured to be dry in the casting process, explosion accidents caused by water or water vapor on the nozzle are prevented, and the submerged nozzle is required to be baked before use in order to ensure that casting is smoothly carried out.
In order to prevent carbon in the refractory material of the submerged nozzle from being oxidized and reduce adhesion of inclusions in molten steel, a glaze layer is coated on the surface of the submerged nozzle in the manufacturing process, and the glaze layer needs to be formed into a compact glaze layer when baked to 900-1100 ℃ so as to play a role in protecting the nozzle and reducing adhesion of inclusions in molten steel, so that the submerged nozzle needs to be baked before use. The most commonly used baking modes of the immersion nozzle at present are an exhaust type baking device and a blowing type baking device, wherein the exhaust type baking device adopts a baking device with an exhaust fan, and the blower is used for exhausting air to pump out high-temperature gas in the tundish through the inner hole of the nozzle, so that the purpose of baking the nozzle is achieved; the blowing type roaster is to replace the exhaust fan with high pressure air flow to extract high temperature air from the middle ladle to roast the immersed water gap. The baking temperature of the inner surface of the immersed nozzle in the two baking modes can reach more than 1000 ℃, the water opening requirement of the nozzle can be met, the outer surface temperature of the nozzle is lower, and is only 500-600 ℃ or even lower, so that the steel is cooled on the outer wall of the nozzle in the water opening process, smooth water opening is affected, even water opening failure is caused, a compact glaze layer is not formed on the outer wall of the nozzle, the immersed nozzle cannot be effectively protected from being oxidized, and the service life of the nozzle is shortened.
Through retrieval, chinese patent CN202555811U, blowing nozzle roaster and Chinese patent CN204770643U, a continuous casting tundish submerged nozzle negative pressure roaster. The two methods both adopt a blowing type water gap roaster, the method can realize the advantages of low investment, low cost, high equipment reliability and the like, but the temperature of the outer surface of the water gap is lower and only 500-600 ℃ or even lower, which can lead to the junction of steel on the outer wall of the water gap in the casting process, influence the smooth casting and even lead to casting failure.
Chinese patent CN101879590a, on-line baking apparatus and baking method for continuous casting tundish submerged nozzle, which uses tundish baking flame to bake the submerged nozzle, although this method can save gas. Flame during tundish baking is affected by gas heat value and a submerged nozzle baking device, the submerged nozzle baking effect is poor, and cold steel is bonded on the outer wall of the nozzle in the casting process due to the fact that the outer surface of the submerged nozzle cannot be baked, so that casting is affected.
In view of the defects of the prior art, the utility model provides the integral submerged nozzle baking device, which can realize that the baking effect of the inner surface and the outer surface of the submerged nozzle is good, and the surface temperature is uniformly distributed, so that the continuous casting is ensured to start.
Disclosure of Invention
1. Problems to be solved
The utility model aims to provide a baking device for an integral submerged nozzle, which can realize that the baking effect of the inner surface and the outer surface of the submerged nozzle is good, the surface temperature is uniformly distributed, the probability of continuous casting of the cold steel is greatly reduced, the casting success rate of continuous casting is improved, and the service life of the submerged nozzle is prolonged.
2. Technical proposal
In order to solve the problems, the utility model adopts the following technical scheme.
The utility model relates to a baking device for an integral immersion nozzle, which comprises a baking furnace arranged below a tundish, wherein the top of the baking furnace is provided with a baking furnace cover, a through hole for the immersion nozzle to pass through is arranged on the baking furnace cover, a horizontally arranged partition is arranged at the lower part of an inner cavity of the baking furnace, a mounting hole is arranged at a position corresponding to the through hole on the partition, the partition divides the inner cavity of the baking furnace into a baking area and a negative pressure area, the baking area is provided with a burner, and a negative pressure environment is formed inside the negative pressure area.
As a further improvement of the utility model, one side of the negative pressure area is provided with a compressed air outlet pipe communicated with the inside of the negative pressure area, and the compressed air outlet pipe is provided with a first compressed air inlet pipe communicated with the negative pressure area, and the pipe diameter of the first compressed air inlet pipe is smaller than that of the first compressed air inlet pipe.
As a further improvement of the utility model, the first compressed air inlet pipe is of an L-shaped structure, the first compressed air inlet pipe comprises an air inlet end perpendicular to the compressed air outlet pipe, an air outlet end perpendicular to the air inlet end is arranged at the bottom of the air inlet end of the first compressed air inlet pipe, and the air outlet end is opened towards the outlet side of the compressed air outlet pipe.
As a further improvement of the utility model, a plurality of burners are arranged, and the plurality of burners are uniformly distributed on the inner side wall of the baking area in a surrounding manner.
As a further improvement of the utility model, two air inlets of the air inlet end of the burner are respectively connected with the second compressed air inlet pipe and the gas inlet pipe.
As a further development of the utility model, the second compressed air inlet pipe and the gas inlet pipe are connected to the inlet end of the burner by means of a compressed air distributor and a gas distributor, respectively.
As a further improvement of the utility model, the air inlet end of the burner and the air outlet end of the burner are in a Y-shaped structure.
As a further improvement of the utility model, the top of the internal cavity of the baking oven is provided with a matched sealing ring, and the sealing ring is positioned below the baking oven cover.
As a further improvement of the utility model, the sealing ring is made of asbestos materials, and the partition and the baking furnace cover are made of refractory materials.
As a further improvement of the utility model, the baking oven is arranged at the bottom of the bottom plate of the tundish.
3. Advantageous effects
Compared with the prior art, the utility model has the beneficial effects that:
(1) According to the baking device for the integral submerged nozzle, a negative pressure environment is formed in the negative pressure area, the lower space of the baking furnace is pumped into negative pressure, so that flames in the tundish are driven to be discharged from the lower opening of the submerged nozzle, the purpose of baking the whole inner surface of the submerged nozzle is achieved, the baking effect on the inner surface and the outer surface of the baked submerged nozzle is good, the temperature distribution is uniform, the probability of continuous casting and casting of cold steel is greatly reduced, the continuous casting and casting success rate is improved, and the service life of the submerged nozzle is prolonged.
(2) According to the baking device for the integral submerged nozzle, provided by the utility model, the number of the nozzles is multiple, the nozzles are uniformly distributed on the upper part of the inner side wall of the baking area in a surrounding mode, so that the outer surface of the submerged nozzle can be uniformly baked, the temperature of the outer surface of the submerged nozzle is uniformly increased, and the temperature distribution of the outer surface is uniform.
(3) According to the baking device for the integral immersion nozzle, disclosed by the utility model, the nozzles in a baking area are communicated with the compressed air distributor and the gas distributor through pipelines, and in order to ensure that the lengths of fires emitted by each nozzle are the same, the diameters of the compressed air distributor and the gas distributor are controlled to be 3-4 times that of the nozzles. The purpose of arranging a plurality of burners around equidistantly is to reduce the uneven temperature rise generated by heating the single burner, and prevent the problem of failure of the surface glaze layer of the submerged nozzle caused by local overhigh temperature. Compressed air and coal gas are respectively led into the coal gas distributor and the compressed air distributor through the second compressed air inlet pipe and the coal gas inlet pipe, and the coal gas and the compressed air are sent to the burner through the distributor for combustion, so that the purpose of baking and heating the outer surface of the submerged nozzle is achieved.
(4) The baking device for the integral submerged nozzle can realize good baking effect on the inner surface and the outer surface of the submerged nozzle, has uniform surface temperature of the nozzle, greatly reduces the probability of continuous casting of the cold steel, and improves the success rate of continuous casting.
Drawings
FIG. 1 is a schematic front view of a baking apparatus for an integral submerged nozzle according to the present utility model;
fig. 2 is a schematic top view of a baking apparatus for an integral submerged nozzle according to the present utility model.
The reference numerals in the figures are:
1. baking oven; 11. a baking area; 12. a negative pressure region; 13. partition; 131. a mounting hole; 14. a compressed air outlet pipe; 141. a first compressed air inlet pipe; 15. a seal ring; 16. a baking furnace cover;
2. a submerged entry nozzle; 3. a burner; 31. a compressed air distributor; 311. a second compressed air inlet pipe; 32. a gas distributor; 321. a gas inlet pipe; 4. a tundish bottom plate.
Detailed Description
For a further understanding of the present utility model, the present utility model will be described in detail with reference to the drawings.
In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The following describes the embodiments of the present utility model in further detail by way of examples of implementation.
Example 1
Referring to fig. 1 and 2, a baking device for an integral submerged nozzle according to the present embodiment includes a baking oven 1 disposed below a tundish, and specifically, in this embodiment, the baking oven 1 is disposed at the bottom of a bottom plate 4 of the tundish. As shown in fig. 1, in this embodiment, a baking furnace cover 16 is disposed at the top of the baking furnace 1, a through hole through which the submerged nozzle 2 passes is formed in the baking furnace cover 16, a partition 13 disposed horizontally is disposed at the lower portion of the inner cavity of the baking furnace 1, a mounting hole 131 is formed in the partition 13 and corresponds to the through hole, the through hole and the mounting hole 131 are both located at the inner central position of the baking furnace 1, and the submerged nozzle 2 is vertically fixed at the inner central position of the baking furnace 1 through the baking furnace cover 16 and the partition 13, so that the inner and outer surfaces of the submerged nozzle 2 are baked conveniently. When the embodiment is used, the bottom of the submerged entry nozzle 2 sequentially passes through the through hole on the baking furnace cover 16 and the mounting hole 131 on the partition 13, the submerged entry nozzle 2 is fixed in the baking furnace 1, the top of the submerged entry nozzle 2 stretches into the tundish, and the bottom of the submerged entry nozzle 2 stretches into the negative pressure region 12.
In this embodiment, the partition 13 divides the internal cavity of the baking oven 1 into a baking area 11 and a negative pressure area 12, the baking area 11 is provided with a burner 3, and the burner 3 sprays flame to the outer surface of the submerged nozzle 2 and baking is performed. In this embodiment, a negative pressure environment is formed in the negative pressure area 12, the lower space of the baking furnace 1 is pumped into negative pressure, so that flames in the tundish are driven to be discharged from the lower opening of the submerged nozzle 2, the purpose of baking the whole inner surface of the submerged nozzle 2 is achieved, the baking effect on the inner surface and the outer surface of the baked submerged nozzle 2 is good, the temperature distribution is uniform, the probability of continuous casting of cold steel is greatly reduced, the continuous casting success rate is improved, and the service life of the submerged nozzle 2 is prolonged.
In this embodiment, a compressed air outlet pipe 14 is disposed at one side of the negative pressure area 12 and is communicated with the inside of the negative pressure area, and a first compressed air inlet pipe 141 is disposed on the compressed air outlet pipe 14 and is communicated with the inside of the negative pressure area, and the pipe diameter of the first compressed air inlet pipe 141 is smaller than that of the first compressed air inlet pipe 141. The first compressed air inlet pipe 141 is in an L-shaped structure, the first compressed air inlet pipe 141 includes an air inlet end perpendicular to the compressed air outlet pipe 14, an air outlet end perpendicular to the air inlet end is provided at the bottom of the air inlet end of the first compressed air inlet pipe 141, and an opening of the air outlet end faces the outlet side of the compressed air outlet pipe 14. Compressed air is introduced into the negative pressure region 12 through the first compressed air inlet pipe 141 and then discharged from the compressed air outlet pipe 14, so that the negative pressure region 12 can be pumped into a negative pressure environment, flames in the tundish are introduced into and penetrate through the whole submerged entry nozzle 2, and the whole inner surface of the submerged entry nozzle 2 is uniformly baked, so that the temperature distribution of the inner surface of the submerged entry nozzle 2 is more uniform.
In this embodiment, the number of the burners 3 is plural, and the plurality of burners 3 are uniformly distributed around the upper portion of the inner side wall of the baking area 11, so that the outer surface of the submerged nozzle 2 can be uniformly baked, and the temperature of the outer surface of the submerged nozzle 2 is uniformly increased, so that the temperature distribution of the outer surface is uniform. Two air inlets of the air inlet end of the burner 3 are respectively connected with a second compressed air inlet pipe 311 and a gas inlet pipe 321. The second compressed air inlet pipe 311 and the gas inlet pipe 321 are connected with the air inlet end of the burner 3 through the compressed air distributor 31 and the gas distributor 32, respectively. Wherein the air inlet end of the burner 3 and the air outlet end of the burner 3 are in a Y-shaped structure. The burners 3 in the baking area 11 are communicated with the compressed air distributor 31 and the gas distributor 32 through pipelines, and in order to ensure that the lengths of the fires emitted by each burner 3 are the same, the diameters of the compressed air distributor 31 and the gas distributor 32 are controlled to be 3-4 times that of the burners 3. The purpose of arranging a plurality of burners 3 around equidistantly is to reduce the uneven heating caused by the heating of a single burner 3 and prevent the problem of failure of the surface glaze layer of the submerged nozzle 2 caused by local overhigh temperature. Compressed air and coal gas are respectively led into the coal gas distributor 32 and the compressed air distributor 31 through the second compressed air inlet pipe 311 and the coal gas inlet pipe 321, and are sent to the burner 3 for combustion through the distributor, so that the purpose of baking and heating the outer surface of the submerged nozzle 2 is achieved.
In this embodiment, a sealing ring 15 is disposed on top of the inner cavity of the baking oven 1, and the sealing ring 15 is located below the baking oven cover 16. The sealing ring 15 is made of asbestos materials, and the partition 13 and the baking furnace cover 16 are made of refractory materials.
When the baking device of the embodiment is specifically used, the following operation steps are performed:
1) In the process of building the tundish, the immersed nozzle 2 is ensured to be vertically arranged, so that the immersed nozzle 2 is conveniently inserted into the baking furnace 1.
2) Before the tundish is baked, the tundish is opened to a baking position, the immersed nozzle 2 is slowly placed into the baking furnace 1, the baking furnace cover 16 is covered, and meanwhile, the baking furnace cover 16 and the top of the baking furnace 1 are sealed by using an asbestos sealing ring 15.
3) And starting to fire and bake the tundish, and after the tundish is baked with big fire, simultaneously, starting to pour for about 1 hour, and opening a valve on the first compressed air inlet pipe 141 to bake the inner surface of the submerged nozzle 2. The surface of the immersed nozzle 2 is provided with a glaze layer, and the glaze layer can form a glass phase protection layer at 900 ℃ to protect the nozzle from oxidation. If the water gap is in the range of 300-800 ℃ for a long time, carbonaceous materials in the water gap are extremely easy to oxidize, and the service life of the water gap is influenced. Therefore, before the valve is opened, the baking temperature of the tundish is ensured to be higher than 1100 ℃, so that the water gap heating rate is ensured to be higher, the residence time is shorter in the range of 300-800 ℃, and the oxidation time is reduced.
4) Simultaneously, valves on the second compressed air inlet pipe 311 and the gas inlet pipe 321 are opened, and the burner 3 is ignited to bake the outer surface of the submerged nozzle 2. Generally, the ratio of the gas flow to the compressed air flow is required to be controlled to be optimal at 1:4, and the amount of the compressed air can be correspondingly increased or decreased if the heat value of the gas fluctuates.
5) The baking time of the immersed nozzle 2 is controlled between 45 and 70min, and the temperature of the inner surface and the outer surface of the nozzle can be ensured to be higher than 1000 ℃ at the moment, so that the continuous casting requirement can be met.
6) If the continuous casting time is delayed for reasons, the baking time of the submerged entry nozzle 2 exceeds the upper limit, and the gas and compressed air amount needs to be adjusted in time to about 80% of the optimal flow, so that the surface temperature of the submerged entry nozzle 2 can be ensured not to be increased or reduced.
The examples of the present utility model are merely for describing the preferred embodiments of the present utility model, and are not intended to limit the spirit and scope of the present utility model, and those skilled in the art should make various changes and modifications to the technical solution of the present utility model without departing from the spirit of the present utility model.
Claims (10)
1. A baking device for an integral submerged nozzle, which is characterized in that: including setting up in the bake out furnace (1) of middle package below, the top of bake out furnace (1) is equipped with toast bell (16), offer the through-hole that supplies immersion nozzle (2) to pass on toast bell (16), bake out furnace (1) inside cavity lower part is equipped with a horizontal arrangement cuts off (13), cut off (13) go up with the corresponding position of through-hole has seted up mounting hole (131), cut off (13) separate bake out furnace (1) inside cavity into toast region (11) and negative pressure region (12), toast region (11) are equipped with nozzle (3), negative pressure region (12) inside negative pressure environment that forms.
2. A baking apparatus for an integral submerged nozzle as claimed in claim 1, wherein: one side of the negative pressure area (12) is provided with a compressed air outlet pipe (14) communicated with the inside of the negative pressure area, the compressed air outlet pipe (14) is provided with a first compressed air inlet pipe (141) communicated with the negative pressure area, and the pipe diameter of the first compressed air inlet pipe (141) is smaller than that of the first compressed air inlet pipe (141).
3. A baking apparatus for an integral submerged nozzle as claimed in claim 2, wherein: the first compressed air inlet pipe (141) is L-shaped, the first compressed air inlet pipe (141) comprises an air inlet end perpendicular to the compressed air outlet pipe (14), an air outlet end perpendicular to the air inlet end is arranged at the bottom of the air inlet end of the first compressed air inlet pipe (141), and an air outlet end opening faces to the outlet side of the compressed air outlet pipe (14).
4. A baking apparatus for an integral submerged nozzle according to any of claims 1-3, characterized in that: the number of the burners (3) is plural, and the burners (3) are uniformly distributed on the inner side wall of the baking area (11) in a surrounding mode.
5. The baking apparatus for an integral submerged nozzle of claim 4, wherein: two air inlets of the air inlet end of the burner (3) are respectively connected with a second compressed air inlet pipe (311) and a gas inlet pipe (321).
6. The baking apparatus for an integral submerged nozzle of claim 5, wherein: the second compressed air inlet pipe (311) and the gas inlet pipe (321) are respectively connected with the air inlet end of the burner (3) through a compressed air distributor (31) and a gas distributor (32).
7. The baking apparatus for an integral submerged nozzle of claim 6, wherein: the air inlet end of the burner (3) and the air outlet end of the burner (3) are in a Y-shaped structure.
8. A baking apparatus for an integral submerged nozzle as claimed in claim 1, wherein: the top of the internal cavity of the baking furnace (1) is provided with a matched sealing ring (15), and the sealing ring (15) is positioned below the baking furnace cover (16).
9. The baking apparatus for an integral submerged nozzle of claim 8, wherein: the sealing ring (15) is made of asbestos materials, and the partition (13) and the baking furnace cover (16) are made of refractory materials.
10. A baking apparatus for an integral submerged nozzle as claimed in claim 1, wherein: the baking oven (1) is arranged at the bottom of the tundish bottom plate (4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320361796.8U CN219402306U (en) | 2023-02-27 | 2023-02-27 | Baking equipment at whole immersion nozzle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320361796.8U CN219402306U (en) | 2023-02-27 | 2023-02-27 | Baking equipment at whole immersion nozzle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219402306U true CN219402306U (en) | 2023-07-25 |
Family
ID=87239769
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202320361796.8U Active CN219402306U (en) | 2023-02-27 | 2023-02-27 | Baking equipment at whole immersion nozzle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN219402306U (en) |
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2023
- 2023-02-27 CN CN202320361796.8U patent/CN219402306U/en active Active
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