Structure to prevent gas leakage from tuyere

Abstract

The present invention is a structure for preventing gas leakage from a tuyere, comprising a small tuyere sleeve, a middle tuyere sleeve and a large tuyere sleeve. The inner cavity of the small tuyere sleeve constitutes an air supply channel of the tuyere. The sealing sleeve at the large diameter end of the small tuyere sleeve is arranged on the inner side of the small diameter end of the middle tuyere sleeve; the sealing sleeve at the large diameter end of the middle tuyere sleeve is arranged on the inner side of the small diameter end of the large tuyere sleeve; at least three pins are provided on the end surface of the large diameter end of the large tuyere sleeve extending in a direction away from the middle tuyere sleeve, and each of the pins is arranged along the axial direction of the large tuyere sleeve; each of the pins is respectively sleeved with a pressure plate that can be fixed axially and circumferentially, and each of the pressure plates can be clamped and pressed against the end surface of the large diameter end of the middle tuyere sleeve at one end away from the pin. The structure uses a pressure plate to connect the large tuyere sleeve and the middle tuyere sleeve together, effectively preventing the problem of gas leakage caused by the gap between the large tuyere sleeve and the middle tuyere sleeve, effectively avoiding the problem of difficulty in replacing the middle tuyere sleeve and the small tuyere sleeve, and realizing safe and low-consumption production of blast furnaces.

Description

Technical Field

[0001] The invention relates to the technical field of iron and steel metallurgy, and in particular to a structure for preventing gas leakage from an air outlet. Background Art

[0002] During the blast furnace smelting process, complex physical and chemical reactions will take place in the furnace, and some harmful elements such as alkali metals and zinc will be brought into the charge. After high-temperature reduction, some of these harmful elements will be discharged from the furnace with blast furnace gas and slag, and some will circulate and accumulate in the furnace, especially in the tuyere area. When replacing the tuyere, a large amount of alkali metals and zinc will be found. In addition, alkali metals and zinc will penetrate into the refractory material, causing abnormal expansion of the refractory material. The corrosion mechanism is as follows: Alkali metals (K, Na) tend to form low-melting-point substances in the blast furnace, which react chemically with the refractory material, causing the refractory material to lose strength and expand abnormally. The reaction of alkali vapor in the furnace: 2R+CO=R 2 O+C (reaction temperature: 850℃~900℃), the generated R 2 O and graphite carbon simultaneously penetrate into the brick joints or pores of the brick lining and deposit, causing the brick lining to expand abnormally. Compared with potassium and sodium, zinc vapor has a larger particle mass and a smaller ion radius. It has greater momentum and penetration at high temperatures and is easier to enter the interior of the brick lining. The zinc vapor that penetrates the brick lining condenses and oxidizes into Zn0 in the brick lining, causing the volume of the brick lining to expand abnormally. The abnormal expansion of the brick lining will cause the upper tuyere sleeve to warp up and deform. The tuyere sleeve and the tuyere sleeve generally use a hard sealing method with a cone surface combination. Once the tuyere sleeve is warped up, the contact length of the lower joint surface will decrease until a gap is generated, resulting in gas leakage.

[0003] Although the relevant regulations for blast furnace ironmaking require the content of harmful elements in the raw materials entering the furnace, most domestic blast furnaces still fail to meet the regulatory requirements for various reasons, and some blast furnaces that mainly use "economic materials" even seriously exceed the standards. Therefore, domestic blast furnaces generally experience gas leakage from the tuyere after they are put into production, which worsens the working environment in front of the furnace and brings safety hazards to the production site. In addition, the upward deformation of the tuyere middle sleeve will also make it difficult to replace the tuyere middle sleeve and small sleeve, prolonging the blast furnace's wind-down and maintenance time, affecting the blast furnace's output and economic benefits.

[0004] Therefore, the inventor, relying on his many years of experience and practice in related industries, proposes a structure to prevent gas leakage from air vents to overcome the defects of the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a structure for preventing gas leakage from the tuyere, so as to overcome the problems existing in the prior art that the deformation of the tuyere middle sleeve easily leads to leakage, and the maintenance and replacement are difficult. The structure adopts a pressure plate to connect the large tuyere sleeve and the middle tuyere sleeve together, so as to effectively prevent the problem of gas leakage caused by the gap between the large tuyere sleeve and the middle tuyere sleeve, and effectively avoid the problem of difficulty in replacing the middle tuyere sleeve and the small tuyere sleeve, so as to realize safe and low-consumption production of the blast furnace.

[0006] The object of the present invention is achieved in this way. A structure for preventing gas leakage from an air outlet comprises a small air outlet sleeve, a middle air outlet sleeve and a large air outlet sleeve which are overlapped inside and outside and are all arranged in a conical sleeve structure. The inner cavity of the small air outlet sleeve constitutes an air supply channel of the air outlet. A sealing sleeve at the large diameter end of the small air outlet sleeve is arranged on the inner side of the small diameter end of the middle air outlet sleeve; a sealing sleeve at the large diameter end of the middle air outlet sleeve is arranged on the inner side of the small diameter end of the large air outlet sleeve; at least three pins are provided on the end surface of the large diameter end of the large air outlet sleeve extending in a direction away from the middle air outlet sleeve, and each of the pins is arranged along the axial direction of the large air outlet sleeve; each of the pins is respectively sleeved with a pressure plate which can be fixed axially and circumferentially, and each of the pressure plates can be clamped and pressed against the end surface of the large diameter end of the middle air outlet sleeve at one end away from the pin.

[0007] In a preferred embodiment of the present invention, at least three fixed bases are arranged on the end surface of the large diameter end of the air outlet sleeve at circumferential intervals, and each of the fixed bases is arranged corresponding to each pin rod, and one end of each pressure plate away from the pin rod can be clamped and pressed against each of the fixed bases.

[0008] In a preferred embodiment of the present invention, each of the pressure plates is arranged in an L shape, including an axial plate arranged along the axial direction of the large air outlet sleeve, the first end of the axial plate is provided with a radial plate arranged along the radial direction of the large air outlet sleeve, a through-rod hole is provided on the radial plate, the radial plate is sleeved on the pin rod through the through-rod hole, the second end of the axial plate is abutted against the fixed base, a wedge plate is abutted between the end of the pin rod away from the air outlet sleeve and the radial plate, and the wedge plate is used to axially compress and fix the pressure plate.

[0009] In a preferred embodiment of the present invention, a wedge plate installation groove is provided on one end of each of the pin rods away from the air port sleeve, and the wedge plate can be inserted into the wedge plate installation groove to axially press the pressure plate.

[0010] In a preferred embodiment of the present invention, each of the fixed bases includes a base body, and a retaining groove is recessed inward from the radial outer side of the air outlet sleeve on the base body, and one circumferential side of each retaining groove is open to form a circumferential opening, and the circumferential opening direction of at least one retaining groove is opposite to the circumferential opening direction of other retaining grooves; the end face of the second end of each axial plate is axially pressed against each of the retaining grooves, and one side surface of the second end of each axial plate is circumferentially pressed against the circumferential side surface of each retaining groove.

[0011] In a preferred embodiment of the present invention, each of the base bodies is protrudingly disposed on an end surface of a large diameter end of the tuyere sleeve.

[0012] In a preferred embodiment of the present invention, each base body is recessed on an end surface of a large diameter end of the tuyere sleeve.

[0013] In a preferred embodiment of the present invention, three pins are provided on the end surface of the large diameter end of the large tuyere sleeve, and the circumferential angles between adjacent pins are 125°, 130° and 105° respectively.

[0014] In a preferred embodiment of the present invention, pin rod mounting holes are axially arranged on the side wall of the large air outlet sleeve, and each of the pin rods is cast-in and inserted and fixed in each of the pin rod mounting holes.

[0015] In a preferred embodiment of the present invention, a closed first annular cavity is provided on the side wall of the tuyere middle sleeve, and the first annular cavity is connected to the first water inlet pipe and the first drain pipe at one end away from the tuyere small sleeve; a closed second annular cavity is provided on the side wall of the tuyere small sleeve, and the second annular cavity is connected to the second water inlet pipe and the second drain pipe at one end located in the tuyere middle sleeve; the first water inlet pipe, the first drain pipe, the second water inlet pipe, the second drain pipe and each of the pressure plates are arranged at circumferential intervals.

[0016] As described above, the structure for preventing gas leakage from air vents provided by the present invention has the following beneficial effects:

[0017] In the structure for preventing gas leakage from the tuyere of the present invention, a pressure plate is used to connect the large tuyere sleeve and the middle tuyere sleeve together, one end of the pressure plate is inserted into a pin rod, and the other end is pressed against the end face of the large diameter end of the middle tuyere sleeve to form a complete connection system, which plays a role in tightening the middle tuyere sleeve. This structure can effectively prevent the problem of gas leakage caused by the gap between the large tuyere sleeve and the middle tuyere sleeve due to the deformation and axial movement of the middle tuyere sleeve; the pressure plate serves as an axial abutment positioning structure and is easy to disassemble. Therefore, this structure can effectively avoid the problem of difficulty in replacing the middle tuyere sleeve and the small tuyere sleeve. The structure for preventing gas leakage from the tuyere of the present invention is an effective measure to achieve safe and low-consumption production of blast furnaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following drawings are intended only to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0019] Figure 1 : It is a side view of the structure for preventing gas leakage from the air outlet of the present invention.

[0020] Figure 2 :for Figure 1 Sectional view along A axis.

[0021] Figure 3: is a schematic diagram of the tuyere sleeve of the present invention.

[0022] Figure 4 : It is a schematic diagram of the installation pin rod of the large air outlet sleeve of the present invention.

[0023] Figure 5 : is a schematic diagram of the tuyere sleeve of the present invention.

[0024] Figure 6 : It is a side view of the air outlet sleeve of the present invention.

[0025] Figure 7 : It is a schematic diagram of the use status of the structure for preventing gas leakage from the air outlet of the present invention.

[0026] In the figure:

[0027] 100. Structure to prevent gas leakage from tuyere;

[0028] 1. Small air inlet sleeve; 11. Second annular cavity; 12. Second water inlet pipe; 13. Second drain pipe;

[0029] 2. Tuyere middle sleeve; 21. First annular cavity; 22. First water inlet pipe; 23. First drain pipe;

[0030] 3. Large air outlet sleeve; 31. Pin rod mounting hole;

[0031] 4. pin rod; 41. wedge plate; 42. wedge plate mounting groove;

[0032] 5. pressure plate; 51. axial plate; 52. radial plate;

[0033] 6. Fixed base; 61. Base body; 62. Stop groove;

[0034] 91. Air supply equipment; 92. Furnace shell. DETAILED DESCRIPTION

[0035] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0036] The specific embodiments of the present invention described herein are only used to explain the purpose of the present invention and cannot be understood as limiting the present invention in any way. Under the guidance of the present invention, technicians can conceive of any possible variations based on the present invention, which should be considered to belong to the scope of the present invention. It should be noted that when an element is referred to as "arranged on" another element, it can be directly on the other element or there can also be a central element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a central element at the same time. The terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, or it can be the internal communication of two elements, it can be directly connected, or it can be indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only implementation method.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0038] like Figures 1 to 7 As shown, the present invention provides a structure 100 for preventing gas leakage from the tuyere, which is used to provide a channel for air supply equipment to supply air into the blast furnace. The structure includes a small tuyere sleeve 1, a middle tuyere sleeve 2 and a large tuyere sleeve 3 (existing technology) which are stacked inside and outside and are all arranged in a cone sleeve structure. The inner cavity of the small tuyere sleeve 1 constitutes an air supply channel of the tuyere, and the outlet of the air supply equipment 91 is inserted into the structure 100 for preventing gas leakage from the tuyere. The outlet of the air supply equipment 91 is sealed and connected with the inner cavity of the small tuyere sleeve 1 to supply air into the blast furnace; the sealing sleeve at the large diameter end of the small tuyere sleeve 1 is arranged on the inner side of the small diameter end of the middle tuyere sleeve 2; the sealing sleeve at the large diameter end of the middle tuyere sleeve 2 is arranged on the inner side of the small diameter end of the large tuyere sleeve 3; the large tuyere sleeve 3 seals and passes through the large sleeve flange fixed on the blast furnace shell 92 (existing technology);

[0039] At least three pins 4 are provided on the end surface of the large diameter end of the large tuyere sleeve 3, extending in the direction away from the middle tuyere sleeve 2, and each pin 4 is arranged along the axial direction of the large tuyere sleeve; each pin 4 is respectively sleeved with a pressure plate 5 that can be fixed axially and circumferentially, and the end of each pressure plate 5 away from the pin 4 can be clamped and pressed against the end surface of the large diameter end of the middle tuyere sleeve 2.

[0040] In the structure for preventing coal gas leakage from the tuyere of the present invention, a pressure plate is used to connect the large tuyere sleeve and the middle tuyere sleeve together, one end of the pressure plate is inserted into a pin rod, and the other end is pressed against the end face of the large diameter end of the middle tuyere sleeve to form a complete connection system, which plays a role in tightening the middle tuyere sleeve. This structure can effectively prevent the problem of coal gas leakage caused by the gap between the large tuyere sleeve and the middle tuyere sleeve due to axial movement caused by deformation of the middle tuyere sleeve (same as the prior art, the deformation of the middle tuyere sleeve 2 is generally caused by the abnormal expansion of the brick lining refractory material below it); the pressure plate serves as an axial abutment positioning structure, which is easy to disassemble, so this structure can effectively avoid the problem of difficulty in replacing the middle tuyere sleeve and the small tuyere sleeve. The structure for preventing coal gas leakage from the tuyere of the present invention is an effective measure to achieve safe and low-consumption production of blast furnaces.

[0041] Further, if Figure 1 , Figure 5 , Figure 6 As shown, at least three fixed bases 6 are arranged at intervals along the circumferential direction on the end surface of the large diameter end of the tuyere sleeve 2, and each fixed base 6 is arranged corresponding to each pin rod 4, and one end of each pressure plate 5 away from the pin rod 4 can be clamped and pressed against each fixed base 6.

[0042] Further, if Figure 2 As shown, each pressure plate 5 is arranged in an L shape, including an axial plate 51 arranged along the axial direction of the large air outlet sleeve 3, a radial plate 52 arranged along the radial direction of the large air outlet sleeve is provided at the first end of the axial plate 51, a through-rod hole is provided on the radial plate 52, the radial plate 52 is sleeved on the pin rod 4 through the through-rod hole, the second end of the axial plate 51 is pressed against the fixed base 6, a wedge plate 41 is pressed against between the end of the pin rod 4 away from the middle air outlet sleeve 2 and the radial plate 52, and the wedge plate 41 is used to axially press the fixed pressure plate 5.

[0043] like Figure 2 , Figure 4 As shown, in this embodiment, a wedge plate installation groove 42 is provided on one end of each pin rod 4 away from the tuyere sleeve 2, and a wedge plate 41 can be inserted into the wedge plate installation groove 42 to axially press the pressing plate 5. The wedge plate fixing method makes the fixing method of the pressing plate 5 more flexible and is suitable for a variety of pressing plates or pin rods of different lengths.

[0044] Further, if Figure 5 , Figure 6As shown, each fixed base 6 includes a base body 61, on which a retaining groove 62 is recessed from the radial outer side of the tuyere middle sleeve to the inside, and one circumferential side of each retaining groove 62 is open to form a circumferential opening, and the circumferential opening direction of at least one retaining groove 62 is opposite to the circumferential opening direction of other retaining grooves; the end face of the second end of each axial plate 51 is axially pressed against each retaining groove 62, and one side surface of the second end of each axial plate 51 is circumferentially pressed against the circumferential side surface of each retaining groove 62, further ensuring the circumferential fixation of the second end of the axial plate 51, avoiding the axial plate 51 from slipping due to deformation of the tuyere middle sleeve 2, and the axial plate 51 can be axially and circumferentially fixed against the fixed base 6, further ensuring the relative fixation between the tuyere middle sleeve and the tuyere large sleeve, avoiding the occurrence of air leakage.

[0045] In this embodiment, each base body 61 can be convexly arranged on the end surface of the large diameter end of the air outlet sleeve 2, or can be concavely arranged on the end surface of the large diameter end of the air outlet sleeve 2 (a groove is arranged on the end surface of the large diameter end of the air outlet sleeve 2, and the base body is arranged in the groove, which is not shown in the figure).

[0046] In a specific embodiment of the present invention, three pins 4 are provided on the end surface of the large diameter end of the large sleeve 3 of the tuyere, and the circumferential angles between adjacent pins 4 are 125°, 130° and 105° respectively. Correspondingly, the number of the pressing plates 5 and the fixed bases 6 is also 3, and the angles of the circumferential intervals thereof correspond to the pins 3. The pins 4, the pressing plates 5 and the fixed bases 6 are arranged at a certain angle to avoid interference with the water pipes (water inlet pipes and drainage pipes, prior art), and are distributed as evenly as possible to achieve uniform force at each point, which is conducive to the stability of the sleeve in the tuyere.

[0047] Further, if Figure 3 As shown, a pin rod mounting hole 31 is axially arranged on the side wall of the large air outlet sleeve 3, and each pin rod 4 is cast-in and inserted and fixed in each pin rod mounting hole 31.

[0048] Further, if Figure 1 As shown, a closed first annular cavity 21 is arranged on the side wall of the tuyere middle sleeve 2, and a first water inlet pipe 22 and a first drain pipe 23 are arranged in communication with the end of the first annular cavity 21 away from the tuyere small sleeve 1; a closed second annular cavity 11 is arranged on the side wall of the tuyere small sleeve 1, and a second water inlet pipe 12 and a second drain pipe 13 are arranged in communication with the end of the second annular cavity 11 located in the tuyere middle sleeve 2; the first water inlet pipe 22, the first drain pipe 23, the second water inlet pipe 12, the second drain pipe 13 and each pressing plate 5 are arranged at intervals in the circumferential direction to avoid interference. The first water inlet pipe 22 and the first drain pipe 23 are the inlet and outlet pipes of the cooling water of the tuyere middle sleeve 2, and the second water inlet pipe 12 and the second drain pipe 13 are the inlet and outlet pipes of the cooling water of the tuyere small sleeve 1, and the cooling water is mainly used for cooling equipment to avoid burning.

[0049] The installation method of the structure 100 for preventing gas leakage from the air outlet of the present invention is as follows:

[0050] First, install the large tuyere sleeve 3 on the large sleeve flange fixed on the blast furnace shell 92. Note that in order to ensure smooth air supply, the large tuyere sleeve 3 and the middle tuyere sleeve 2 are in a horizontal state, and the small tuyere sleeve 1 is in a horizontal or inclined state (determined according to needs. In a specific embodiment of the present invention, the small tuyere sleeve 1 is in a downwardly inclined state from the outside to the inside, that is, the small tuyere sleeve 1 will be in the innermost and lowermost position);

[0051] Then, push the middle tuyere sleeve 2 and the small tuyere sleeve 1 into the large tuyere sleeve 3 to ensure that the joint surfaces between the adjacent structures are in close contact and sealed; in this process, pay attention to adjust the middle tuyere sleeve 2 so that the fixed base 6 on it corresponds to the pin rod 4 on the large tuyere sleeve 3 one by one;

[0052] Then, each pressing plate 5 is respectively sleeved on each pin rod 4, and the second end of the axial plate 51 abuts against the retaining groove 62 on the fixed base 6, and the circumferential position is adjusted to ensure the circumferential abutment;

[0053] Finally, the wedge plate 41 is wedged into the wedge plate installation groove 42 to axially press the pressure plate 5 .

[0054] As described above, the structure for preventing gas leakage from air vents provided by the present invention has the following beneficial effects:

[0055] In the structure for preventing gas leakage from the tuyere of the present invention, a pressure plate is used to connect the large tuyere sleeve and the middle tuyere sleeve together, one end of the pressure plate is inserted into a pin rod, and the other end is pressed against the end face of the large diameter end of the middle tuyere sleeve to form a complete connection system, which plays a role in tightening the middle tuyere sleeve. This structure can effectively prevent the problem of gas leakage caused by the gap between the large tuyere sleeve and the middle tuyere sleeve due to the deformation and axial movement of the middle tuyere sleeve; the pressure plate serves as an axial abutment positioning structure and is easy to disassemble. Therefore, this structure can effectively avoid the problem of difficulty in replacing the middle tuyere sleeve and the small tuyere sleeve. The structure for preventing gas leakage from the tuyere of the present invention is an effective measure to achieve safe and low-consumption production of blast furnaces.

[0056] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by any person skilled in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A structure for preventing gas leakage from air vents, characterized in that: It comprises a small air outlet sleeve, a middle air outlet sleeve and a large air outlet sleeve which are overlapped inside and outside and are all arranged in a cone sleeve structure. The inner cavity of the small air outlet sleeve constitutes an air supply channel of the air outlet. The sealing sleeve at the large diameter end of the small air outlet sleeve is arranged on the inner side of the small diameter end of the middle air outlet sleeve; the sealing sleeve at the large diameter end of the middle air outlet sleeve is arranged on the inner side of the small diameter end of the large air outlet sleeve; at least three pins are provided on the end surface of the large diameter end of the large air outlet sleeve extending in the direction away from the middle air outlet sleeve, and each of the pins is arranged along the axial direction of the large air outlet sleeve; each of the pins is respectively sleeved with a pressure plate which can be fixed in the axial direction and the circumferential direction, and each of the pressure plates can be clamped and pressed against the end surface of the large diameter end of the middle air outlet sleeve at one end away from the pin; At least three fixed bases are arranged at intervals along the circumferential direction on the end surface of the large diameter end of the tuyere sleeve, and each of the fixed bases is arranged corresponding to each pin rod, and one end of each pressure plate away from the pin rod can be clamped and pressed against each of the fixed bases; Each of the pressure plates is arranged in an L shape, including an axial plate arranged along the axial direction of the large sleeve of the tuyere, a radial plate arranged along the radial direction of the large sleeve of the tuyere is provided at the first end of the axial plate, a through-rod through-hole is provided on the radial plate, the radial plate is sleeved on the pin rod through the through-rod through-hole, the second end of the axial plate abuts against the fixed base, a wedge plate is abutted against an end of the pin rod away from the sleeve of the tuyere and the radial plate, and the wedge plate is used to axially press and fix the pressure plate; Each of the fixed bases comprises a base body, on which a retaining groove is recessed inwardly from the radial outer side of the air outlet sleeve, and one circumferential side of each retaining groove is open to form a circumferential opening, and the circumferential opening direction of at least one retaining groove is opposite to the circumferential opening direction of other retaining grooves; the end surface of the second end of each axial plate is axially pressed against each of the retaining grooves, and one side surface of the second end of each axial plate is circumferentially pressed against the circumferential side surface of each retaining groove; A wedge plate installation groove is arranged on one end of each pin rod away from the air port sleeve, and the wedge plate can be inserted into the wedge plate installation groove to axially press the pressure plate.

2. The structure for preventing gas leakage from air vents according to claim 1, characterized in that: Each base body is convexly arranged on the end surface of the large diameter end of the air inlet sleeve.

3. The structure for preventing gas leakage from air vents according to claim 1, characterized in that: Each base body is recessed on the end surface of the large diameter end of the tuyere sleeve.

4. The structure for preventing gas leakage from air vents according to claim 1, characterized in that: Three pins are arranged on the end surface of the large diameter end of the large tuyere sleeve, and the circumferential angles between adjacent pins are 125°, 130° and 105° respectively.

5. The structure for preventing gas leakage from air vents according to claim 1, characterized in that: A pin rod mounting hole is arranged axially on the side wall of the large air outlet sleeve, and each of the pin rods is cast-in and inserted and fixed in each of the pin rod mounting holes.

6. The structure for preventing gas leakage from air vents according to claim 1, characterized in that: A closed first annular cavity is arranged on the side wall of the tuyere middle sleeve, and a first water inlet pipe and a first drain pipe are connected to the end of the first annular cavity away from the tuyere small sleeve; a closed second annular cavity is arranged on the side wall of the tuyere small sleeve, and a second water inlet pipe and a second drain pipe are connected to the end of the second annular cavity located in the tuyere middle sleeve; the first water inlet pipe, the first drain pipe, the second water inlet pipe, the second drain pipe and each of the pressure plates are arranged at circumferential intervals.

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