Converter oxygen lance inlet sealing device

Abstract

The invention discloses a converter oxygen lance inlet sealing device. Comprising an upper sealing cover, an inlet sealing cover, a telescopic pipe cover and a butt joint pipe opening. The upper sealing cover is fixed with a lance body of the converter oxygen lance, the upper sealing cover is connected with the inlet sealing cover through the telescopic pipe cover, and the butt joint pipe orifice is fixedly connected with a converter top platform; when the oxygen lance descends, the inlet sealing cover can be connected with the butt joint pipe orifice in a self-adaptive mode, when the oxygen lance carries out blowing, the telescopic pipe cover can stretch out and draw back vertically along with the oxygen lance, the whole device seals the inlet of the oxygen lance, harmful gas is not leaked to the outside, an original nitrogen sealing scheme is replaced, the using amount of nitrogen is saved, and the effects of reducing pollution, saving energy and reducing emission are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of converter steelmaking, and particularly to a sealing device for the inlet of a converter oxygen lance. Background Art

[0002] During the oxygen lance blowing process in converter steelmaking, a large amount of gas is generated. When the reaction is intense, a large amount of toxic and harmful flue gas escapes from the oxygen lance water jacket and enters the interior of the steelmaking workshop. The main components of the flue gas include unburned CO, which poses a great potential safety hazard to normal safe production. The traditional method generally introduces a large amount of nitrogen at the oxygen lance inlet to block the overflowing dust. This not only consumes a large amount of nitrogen and increases the blowing cost, but also has a very limited sealing effect on the dust.

[0003] In the existing solutions, a simple and practical method is to use a seamless pipe with a diameter of Φ57 to bend and manufacture a self-made steam ring pipe through a pipe bender. However, in the actual use process, on the premise that the steam pressure in the main steam pipe is stable, the steam of this self-made steam ring pipe is extremely unstable, and no steam vortex is designed, so it still cannot achieve a good sealing effect. In the field of non-ferrous metal smelting, the method of increasing the sealing cover is adopted to control the dust. However, due to the generally low temperature in non-ferrous metal smelting, the structure of the furnace body and the working mode of the oxygen lance are quite different from those in iron and steel metallurgy, and the sealing, high-temperature resistance, and fatigue resistance cannot meet the requirements of converter steelmaking. Especially in converter steelmaking, the working temperature is usually between 1500 - 1700 °C, and the high-temperature factor needs to be considered for all parts of the sealing device; during the oxygen lance blowing process in the converter, the amplitude and frequency of the up and down movement of the oxygen lance need to be considered, and the fatigue resistance factor needs to be considered for the sealing device; after the smelting is completed, the oxygen lance needs to be completely lifted, and the sealing device needs to be completely separated from the converter. When smelting again, a sealed environment needs to be formed again with the oxygen lance inlet, and the factor of being able to achieve repeated self-adaptive connection and sealing needs to be considered; at the same time, the use cost needs to be comprehensively considered, and the problem of reducing the nitrogen consumption needs to be solved. Based on the above factors, the present invention provides the following design scheme. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a sealing device for the inlet of an oxygen lance used in converter steelmaking. A technical solution with high-temperature resistance, fatigue resistance, and the ability to achieve repeated self-adaptive connection is provided for the technical characteristics of converter steelmaking, so as to solve the technical problems of improving the dust blocking effect and reducing the use cost.

[0005] The technical solution of the present invention is as follows:

[0006] A converter oxygen lance inlet sealing device includes an upper sealing cover, an inlet sealing cover, a telescopic pipe cover, and a butt joint pipe orifice. There is an oxygen lance passage left in the center of the sealing device. The upper sealing cover is fixed to the lance body of the converter oxygen lance. The oxygen lance passes through the oxygen lance passage left in the center of the upper sealing cover, the inlet sealing cover, and the telescopic pipe cover. The upper sealing cover and the inlet sealing cover are connected through the telescopic pipe cover. The butt joint pipe orifice is fixedly connected to the converter roof platform. When the oxygen lance descends, the inlet sealing cover abuts against the butt joint pipe orifice under the action of gravity; when the lifting height of the oxygen lance is within the maximum stretching length range of the telescopic pipe cover, the inlet sealing cover still abuts against the butt joint pipe orifice; when the lifting height of the oxygen lance exceeds the maximum stretching length of the telescopic pipe cover, the inlet sealing cover and the butt joint pipe orifice can be separated.

[0007] Further, there is a self-heat exchange device inside the inlet sealing cover. The self-heat exchange device is of a cylindrical structure. The axis direction of the cylinder is perpendicular to the circular surface direction of the inlet sealing cover. The oxygen lance passes through the center of the cylinder. On the one hand, the self-heat exchange device increases the weight of the inlet sealing cover, so as to increase the pressure during the process of centering and abutting against the inlet butt joint pipe by gravity; on the other hand, when the oxygen lance blows oxygen, high-temperature flue gas will pour into the inside of the sealing cover at the central gap of the cylinder, and the cylinder produces a cooling and heat dissipation effect, preventing high-temperature flue gas from damaging devices such as the telescopic pipe cover.

[0008] Further, the butt joint pipe orifice is of a cylindrical structure, and there are multiple ribs around the cylinder. The ribs, on the one hand, increase the strength of the butt joint pipe and are not easily deformed during the repeated lifting and falling of the inlet sealing cover and the repeated abutting and separating processes, ensuring the sealing effect; on the other hand, they increase the heat dissipation effect of the material in the high-temperature smelting environment, preventing structural deformation and changes in material properties caused by excessive temperature.

[0009] Further, the outer edge of the inlet sealing cover has a flared opening. During the process of the inlet sealing cover falling with the oxygen lance, the flared opening has a self-centering effect when docking with the butt joint pipe orifice, making the docking angle accurate and enhancing the sealing effect; when the inlet sealing cover is close to the butt joint pipe orifice, it controls the flow direction of hot air, so that the hot air does not immediately flow upward to damage devices such as the telescopic pipe cover and the external limit belt.

[0010] Further, a sealing filler is arranged at the lower part of the inlet sealing cover, at the annular contact part when the inlet sealing cover abuts against the butt joint pipe orifice. The sealing filler is a material with certain flexibility, and is resistant to high temperature and corrosion, such as graphite and asbestos materials. It increases the docking sealing effect and stability.

[0011] Furthermore, a slag blocking assembly is fixedly installed on the oxygen lance barrel and moves up and down with the oxygen lance. When the oxygen lance passes through the oxygen lance passage, the slag blocking assembly can also pass through the oxygen lance passage. When the oxygen lance passes through the oxygen lance passage, since it cannot fit tightly with the passage completely, a large amount of gaps will be left between the passages. During the oxygen blowing process of the oxygen lance, a large amount of flue gas in the furnace will pour into the inside of the sealing device through these gaps, damaging the device. Adding a slag blocking assembly can fill the gaps to a certain extent and greatly reduce the amount of flue gas pouring into the inside of the sealing device. The slag blocking assembly can be modified from the original nitrogen sealing plug of the oxygen lance, changing the material to increase the strength and heat resistance of the original nitrogen sealing plug, or retaining part of the nitrogen blowing function of the nitrogen sealing plug while reducing the nitrogen blowing amount. Reducing the loss of nitrogen and increasing the sealing effect of the sealing cover.

[0012] Furthermore, the telescopic pipe cover is of a corrugated pipe structure and is composed of a flexible high-temperature resistant material, and the joints of the corrugations are sewn and connected. When the oxygen lance descends, the lower inlet sealing cover of the telescopic pipe cover abuts against the butt joint pipe orifice. As the oxygen lance gradually descends, the telescopic pipe cover is compressed. When the oxygen lance reaches the lowest point, the length of the telescopic pipe cover after being compressed is still greater than the minimum length. When the oxygen lance is lifted, when the lifting height exceeds the maximum stretching length of the telescopic pipe cover, the inlet sealing cover is lifted with the oxygen lance and separated from the butt joint pipe orifice. The corrugated pipe is not an integral structure but is sewn and connected by several pipe rings. Looking at the corrugations locally, the suture at the pipe ring is not in an "S" shape but in a "zigzag" shape, that is, there is a certain overlapping amount at the suture of the two sections of annular materials, which increases the fatigue resistance when the corrugated pipe is bent, and the sewn connection also increases the heat dissipation effect of the pipe wall.

[0013] Furthermore, a limiting belt is provided on the outer side of the telescopic pipe cover. The limiting belt is parallel to the outer wall of the telescopic pipe cover. The upper end of the limiting belt is connected to the upper sealing cover, the lower end of the limiting belt is connected to the inlet sealing cover, and the middle part of the limiting belt is connected to the corrugation of the telescopic pipe cover. The length of the limiting belt is equal to the maximum stretching length of the telescopic pipe cover. When the telescopic pipe cover is stretched, the limiting belt limits the maximum stretching length of the corrugated pipe, preventing the corrugated pipe from being damaged due to excessive tensile force.

[0014] Since the pipe cover material is not a single integral material, during the stretching process of the corrugated pipe, due to uneven materials or different tensile strengths at the joints, the situation of increased local fatigue will inevitably occur. By fixing and connecting the limiting belt to the telescopic pipe at intervals, each section of the corrugated pipe is limited, that is, a maximum stretching length is set for each section, so that the maximum force of the corrugated pipe is evenly distributed in each section of the pipe cover interval.

[0015] The beneficial effects of the present invention are as follows: The present invention provides a sealing device designed for the inlet of a converter oxygen lance, overcoming the problem in the prior art that the sealing cover cannot adaptively close and separate from the oxygen lance inlet; it is suitable for high-temperature environments and has the characteristics of anti-fatigue and durability; it enhances the smoke and dust blocking effect, reduces the nitrogen emission, and achieves the effects of reducing pollution, energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematically shows the front view of the telescopic sealing device for the converter oxygen lance inlet;

[0017] Figure 2 Schematically shows the structural view of the local stitching part of the telescopic pipe cover;

[0018] Explanation of the reference numerals in the drawings: 1, upper sealing cover; 2, telescopic pipe cover; 3, inlet sealing cover; 4, butt joint pipe orifice; 5, oxygen lance channel; 6, converter oxygen lance; 7, furnace top platform; 8, self-heat exchange device; 9, rib; 10, flared opening; 11, sealing packing; 12, slag blocking assembly; 13, limiting band; 21, pipe ring stitching place.

[0019] Figure 1 Among them, 6, the converter oxygen lance, and 7, the furnace top platform are the original devices of the converter, not the technical features protected by the present invention, and are only used to illustrate the structures and positions of the components of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] Hereinafter, the disclosed exemplary embodiments will be described in more detail with reference to the drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0021] As shown in the figure, the embodiment of the present application provides a sealing device for the converter oxygen lance inlet, including an upper sealing cover 1, an inlet sealing cover 3, a telescopic pipe cover 2, and a butt joint pipe orifice 4.

[0022] The oxygen lance 6 is vertically placed perpendicular to the ground in the application environment. The "upper", "lower" and other orientations used in this description are based on the relative positions when the oxygen lance is vertically placed.

[0023] The upper sealing cover 1 is fixed to the upper part of the oxygen lance 6 gun body, and the oxygen lance 6 passes through the oxygen lance channel 5 in the center of the upper sealing cover, the inlet sealing cover 3, and the telescopic pipe cover 2.

[0024] The upper end of the telescopic pipe cover 2 is connected to the upper sealing cover 1, and the lower end is connected to the inlet sealing cover 3. The inlet sealing cover 3 stretches the telescopic pipe cover 2 under the action of gravity, and the length is the maximum length of the telescopic pipe cover 2 restricted by the limiting band.

[0025] The butt joint pipe orifice 4 is fixedly connected to the converter top platform 7.

[0026] During the process when the oxygen lance 6 starts to move downward and extends into the converter for blowing, the inlet seal cover 3 descends by gravity, first contacts and tightly connects with the butt joint pipe orifice 4.

[0027] An auto heat exchange device 8 is arranged inside the inlet seal cover 3. The auto heat exchange device 8 is of a cylindrical structure. By adjusting the counterweight, when the inlet seal cover 3 is connected to the butt joint pipe orifice 4 by gravity, the contact pressure is increased, enhancing the self - centering and sealing effect; when the flue gas gushes out in the cylindrical structure, the temperature of the cylindrical pipe wall is reduced.

[0028] Multiple ribs 9 are arranged on the side wall of the butt joint pipe orifice 4, increasing the strength of the butt joint pipe orifice. In a high - temperature environment, these ribs 9 enhance the heat dissipation effect, avoiding the softening of the material due to excessive temperature and affecting the sealing effect.

[0029] The outer edge of the inlet seal cover 3 has a flared opening 10, which produces a self - centering effect when contacting the butt joint pipe orifice 4, overcoming the position deviation caused by jitter during the descending process and increasing the connection precision between the inlet seal cover 3 and the butt joint pipe orifice 4.

[0030] A sealing filler 11 is arranged at the butt joint of the bottom of the inlet seal cover 3 and the butt joint pipe orifice. The sealing filler is preferably graphite, making the connection tighter and increasing the sealing effect when the inlet seal cover abuts against the butt joint pipe orifice.

[0031] The inlet seal cover 3 gradually drops with the oxygen lance 6 and is tightly connected to the butt joint pipe orifice 4 under the action of gravity. During the continuous downward movement of the oxygen lance 6, the length of the telescopic pipe cover 2 starts to be compressed. When the oxygen lance 6 drops to the lowest point, it is ensured that there is still a certain compression space in the telescopic pipe cover 2. When the oxygen lance 6 performs blowing, it moves up and down periodically. The telescopic pipe cover 2 is stretched and compressed along with the oxygen lance, and it is ensured that the movement range is still between the maximum length that the telescopic pipe cover 2 can be stretched and the minimum length that it can be compressed, and the inlet seal cover 3 is still tightly connected to the butt joint pipe orifice 9.

[0032] A slag - blocking assembly 12 is fixedly installed on the oxygen lance. The slag - blocking assembly 12 is annular, surrounds the oxygen lance 6 and is fixed on the oxygen lance, filling the large gap between the oxygen lance and the channel, blocking a large amount of slag carried out when the flue gas is blown out and damaging the device. Preferably, the slag - blocking assembly 12 can be refitted from the original nitrogen seal ring of the oxygen lance, such as replacing it with high - strength and high - temperature - resistant materials while retaining the property of being able to pass nitrogen for sealing. A small amount of nitrogen can be introduced into the slag - blocking device to increase the slag - blocking effect and save nitrogen consumption compared with the original nitrogen seal ring.

[0033] The telescopic pipe cover 2 is of a corrugated pipe structure and is made of a flexible high-temperature resistant material. The corrugated pipe is sewn and connected by small sections of annular materials, and the pipe ring sewing joint 21 is in a zigzag shape. The fatigue resistance is increased during the frequent telescopic process of the pipe cover, making it not easy to break. The sewing gap helps with heat dissipation and improves the service life.

[0034] The outer side of the telescopic pipe cover 2 is provided with a limit strip 13. The limit strip 13 is parallel to the axial direction of the telescopic pipe cover 2. The upper end of the limit strip 13 is connected to the upper sealing cover 1, the lower end is connected to the inlet sealing cover 3, and the middle part is connected to the corrugation of the telescopic pipe cover 2. The length of the limit strip 13 is equal to the maximum stretching length of the telescopic pipe cover.

[0035] When the oxygen lance blows, a large amount of gas is blown into the converter. A large amount of flue gas in the furnace will gush out from the oxygen lance inlet. Through the sealing device of the present invention, harmful gases are blocked inside the sealing device and do not leak into the workshop working environment. After the oxygen lance blowing is completed, the oxygen lance is lifted to completely leave the converter. The inlet sealing device moves upward with the oxygen lance. After the telescopic pipe cover 2 reaches the maximum stretching length, under the action of the pulling force, the inlet sealing cover 3 is separated from the butt joint pipe orifice 4 and returns to the original position with the oxygen lance.

Claims

1. A sealing device for the inlet of a converter oxygen lance, characterized in that: It includes an upper sealing cover, an inlet sealing cover, a telescopic pipe cover, and a butt joint pipe orifice. There is an oxygen lance passage left in the center of the oxygen lance inlet sealing device. The upper sealing cover is fixedly connected to the upper part of the converter oxygen lance. The upper sealing cover and the inlet sealing cover are connected through the telescopic pipe cover. The oxygen lance passes through the oxygen lance passage in the center of the upper sealing cover, the inlet sealing cover, and the telescopic pipe cover. The butt joint pipe orifice is fixed on the furnace top platform. When the oxygen lance drops, the inlet sealing cover abuts against the butt joint pipe orifice.

2. The converter oxygen lance inlet sealing device according to claim 1, characterized in that There is a self-heat exchange device inside the inlet sealing cover. The self-heat exchange device is of a cylindrical structure. The axis direction of the cylinder is perpendicular to the circular surface direction of the inlet sealing cover. The oxygen lance can pass through the center of the cylinder.

3. The converter oxygen lance inlet sealing device according to claim 1, characterized in that The butt joint pipe orifice is of a cylindrical structure, and multiple ribs are provided on the side wall of the butt joint pipe orifice.

4. The converter oxygen lance inlet sealing device according to claim 1, characterized in that The outer edge of the inlet sealing cover has a flared opening.

5. The converter oxygen lance inlet sealing device according to claim 1, characterized in that Sealing packing is arranged at the lower part of the inlet sealing cover. The sealing packing is located at the annular contact part when the inlet sealing cover abuts against the butt joint pipe orifice.

6. The converter oxygen lance inlet sealing device according to claim 1, characterized in that It includes a slag blocking component. The slag blocking component is fixed on the oxygen lance and is located at the lower part of the inlet sealing cover. When the oxygen lance moves up and down, the slag blocking component can pass through the butt joint pipe orifice.

7. The converter oxygen lance inlet sealing device according to claim 1, characterized in that The telescopic pipe cover is of a corrugated pipe structure. The telescopic pipe cover is made of a soft high-temperature resistant material. The connections of the corrugations are sewn connections, and the sewing joints are in a "zigzag" shape.

8. The converter oxygen lance inlet sealing device according to claim 1, characterized in that There is a limiting band on the outside of the telescopic pipe cover. The limiting band is parallel to the axis direction of the telescopic pipe. The upper end of the limiting band is connected to the upper sealing cover, the lower end of the limiting band is connected to the inlet sealing cover, the middle part of the limiting band is connected to the corrugation of the telescopic pipe cover, and the length of the limiting band is equal to the maximum stretching length of the telescopic pipe cover.

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