A flexible plugging structure for casing holes on the valve side of a converter transformer valve hall

Abstract

The present invention discloses a flexible plugging structure for the hole of the casing on the valve side of the converter transformer valve hall, which relates to the technical field of plugging the casing on the valve side of the converter transformer valve of the converter station. Its converter transformer casing is installed in the converter transformer casing installation hole of the fireproof plugging plate and the explosion-proof plugging plate; the converter transformer casing installation hole and the converter transformer casing are densely filled with aluminum silicate fiber blanket, aluminum silicate plate and first movable fireproof ring, the outer connection between the aluminum silicate fiber blanket and the fireproof plugging plate is sealed by the second movable fireproof ring, and is sealed by fireproof sealant, and the second movable fireproof ring is fixed to the fireproof plugging plate by stainless steel dovetail nails; the fireproof plugging plate, the second movable fireproof ring and the converter transformer casing are integrally wrapped and sealed by a silicone rubber plate, and are sealed by fireproof sealant. The advantages of the present invention are: by performing multi-layer dense filling on the converter transformer casing installation gap, the strength of the plugging structure is enhanced, the overall fireproof and smokeproof performance of the plugging system is improved, and the overall fire resistance performance is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of bushing plugging on a converter transformer valve side of a converter station, and in particular to a flexible plugging structure for bushing holes on a valve side of a converter transformer valve hall. Background Art

[0002] The valve hall of the converter station is a closed building for placing converter valves. The converter transformer bushing design needs to be installed through the wall. When installing the converter transformer bushing, a fireproof and explosion-proof structure needs to be set between the converter transformer bushing and the firewall to meet the fireproof and explosion-proof requirements. Since the converter transformer bushing is generally filled with oil after the valve hall plug is installed, the bushing becomes heavier after oil filling and sinks about 2-3 mm, resulting in gaps in the upper part of the small plug, affecting the fireproof performance and sealing. The converter transformer bushing will vibrate during operation, with an amplitude of millimeters. After long-term operation, the vibration compression will cause gaps in the aluminum silicate fiber blanket that was originally densely filled in the small plugging part, which will also affect the fireproof performance and sealing. The plugging structure of each joint in the fireproof and explosion-proof structure needs to achieve good explosion-proof, fireproof, smoke-proof and waterproof effects to meet daily operation and fire requirements.

[0003] In the explosion-proof and fireproof structure of the converter transformer bushing of the converter station, a flexible plugging structure is used at the connection between the converter transformer bushing and the explosion-proof and fireproof structure. In the prior art, only a simple plugging structure is used at the connection between the converter transformer bushing and the explosion-proof and fireproof structure, and due to the vibration of the bushing during operation, the sealing performance of the plugging is not ideal. Once a fire or explosion occurs, the weak point at the plugging will become the main breakthrough point for the fire to spread, affecting the overall explosion-proof and fireproof performance, and posing a safety hazard.

[0004] As in the prior art, a fireproof and explosion-proof structure for sealing the valve side bushing of a converter transformer in a converter station with application number 201910441087.9 is disclosed, which includes a fireproof sealing plate and a converter transformer bushing mounting hole, the converter transformer bushing is installed in the converter transformer bushing mounting hole, and an aluminum silicate needle-punched blanket layer is filled between the hole wall of the converter transformer bushing mounting hole and the outer wall of the converter transformer bushing; the fireproof sealing plate includes a first metal surface structure rock wool composite plate, a second metal surface structure rock wool composite plate and a non-magnetic stainless steel impact-resistant plate, and the aluminum silicate needle-punched blanket layer is located between the hole wall of the converter transformer bushing mounting hole opened by the first metal surface structure rock wool composite plate and the second metal surface structure rock wool composite plate and the outer wall of the converter transformer bushing. Although the above patent has achieved fireproof and explosion-proof effects to a certain extent, the outer wall of the converter transformer bushing and the side surface of the fireproof sealing plate are sealed only by a ceramic silicone rubber sealing sleeve, and the fireproof sealing plate, the aluminum silicate needle-punched blanket layer, and the outer wall of the converter transformer bushing are sealed as a whole, with poor sealing performance and low sealing strength. In addition, the connection between the converter transformer bushing and the fireproof sealing plate is separated by only a whole piece of aluminum silicate needle-punched blanket layer, with poor fireproof performance, resulting in reduced overall fireproof and explosion-proof performance. In a fire in the transformer, the high temperature generated will cause the stainless steel panel to deform greatly, causing the originally sealed connection to deform or detach, causing smoke and fire to escape, increasing safety hazards.

[0005] Therefore, it is necessary to design a flexible sealing structure for the holes of the casing on the valve side of the converter transformer valve hall with good sealing performance to solve the above problems and improve the fire and explosion resistance. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a flexible sealing structure for the holes of the valve side casing of the converter transformer valve hall, which can solve the problem of the gap between the valve side casing of the converter transformer valve hall and the anti-explosion sealing and fire-proof sealing, and design a movable fireproof ring and a movable anti-explosion ring, so that when the valve side casing of the converter transformer valve hall sinks and vibrates, the movable fireproof ring will be displaced accordingly. During daily operation, the movable fireproof ring and the valve side casing of the converter transformer valve hall vibrate synchronously; when an explosion occurs, the movable anti-explosion ring can effectively resist the explosion force to prevent the explosion shock wave from the converter transformer valve hall from The gap between the valve side casing of the rheological valve hall and the explosion-proof stainless steel panel passes through, destroying the fireproof sealing structure; when a fire occurs, the movable fireproof ring can effectively ensure the sealing of the small plugging, reduce the air heat convection after the fire, and enhance the thermal insulation performance of the small plugging and the entire sealing system. In addition, the movable fireproof ring can enhance the load-bearing capacity of the entire sealing system, enhance the structural strength of the rheological valve casing and the explosion-proof and fireproof plugging, and enhance the overall explosion-proof, fire-proof and smoke-proof performance of the sealing system, ensuring the integrity of the sealing system without smoke leakage or smoke leakage.

[0007] In order to solve the above technical problems, the technical solution of the present invention is as follows: it includes explosion-proof plugging and fire-proof plugging sealed and installed on the fire wall of the converter transformer valve hall, the explosion-proof plugging plate and the fire-proof plugging plate are provided with converter transformer bushing installation holes matching the converter transformer bushing, the converter transformer bushing is obliquely installed in the converter transformer bushing installation hole, the explosion-proof plugging plate has an explosion-proof stainless steel panel and an explosion-proof stainless steel keel; the fire-proof plugging plate has a stainless steel surface rock wool composite plate and a stainless steel surface aluminum silicate composite plate, and an air layer structure is added between the stainless steel surface rock wool composite plate and the stainless steel surface aluminum silicate composite plate through the stainless steel keel;

[0008] The explosion-proof stainless steel keel is welded by non-magnetized stainless steel square tubes, the explosion-proof stainless steel panel and the explosion-proof stainless steel keel are connected by stainless steel bolts, the explosion-proof stainless steel keel is fixed to the wall by stainless steel bolts, and a movable explosion-proof ring is provided at the installation hole of the converter transformer bushing opened on the explosion-proof stainless steel panel;

[0009] The hole wall of the converter transformer bushing installation hole and the converter transformer bushing are densely filled with an aluminum silicate fiber blanket, an aluminum silicate plate and a first movable fireproof ring. The junction between the outer side of the aluminum silicate fiber blanket and the outer side of the fireproof sealing plate is sealed by a second movable fireproof ring. The end of the second movable fireproof ring and the junction between the fireproof sealing plate and the converter transformer bushing are sealed by fireproof sealant, and the second movable fireproof ring and the fireproof sealing plate are fixed by stainless steel dovetail nails.

[0010] The outer side of the fireproof sealing plate, the outer side of the second movable fireproof ring and the outer wall of the converter transformer bushing are integrally wrapped and sealed by the silicone rubber plate, and the joints between the corners of the silicone rubber plate and the converter transformer bushing, the second movable fireproof ring and the fireproof sealing plate are all sealed by fireproof sealant, and the silicone rubber plate wrapped around the outside of the converter transformer bushing is fixed by a stainless steel clamp, and the silicone rubber plate wrapped around the outside of the fireproof sealing plate is fixed to the fireproof sealing plate by stainless steel dovetail nails and a stainless steel pressure plate.

[0011] Furthermore, a movable explosion-proof ring is provided at the converter transformer bushing mounting hole opened on the explosion-proof stainless steel panel, the dovetail nail mounting hole on the movable explosion-proof ring is larger than the dovetail nail diameter, a gasket with a radius larger than the dovetail nail mounting hole is installed between the movable explosion-proof ring and the dovetail nail, the movable explosion-proof ring is fixed to the explosion-proof stainless steel panel by dovetail nails, and the movable explosion-proof ring and the converter transformer bushing are sealed and fixed by using fire-proof sealant.

[0012] Furthermore, between the stainless steel surface rock wool composite plate at the converter transformer bushing installation hole and the outer tube wall of the converter transformer bushing, and between the stainless steel surface aluminum silicate composite plate and the outer tube wall of the converter transformer bushing, aluminum silicate fiber blankets are densely filled respectively, and between the two aluminum silicate fiber blankets is filled with aluminum silicate board and the first movable fireproof ring.

[0013] Furthermore, the aluminum silicate plate extends into an air layer structure added between the stainless steel surface rock wool composite plate and the stainless steel surface aluminum silicate composite plate, and one side of the aluminum silicate plate is bonded to the stainless steel surface rock wool composite plate.

[0014] Furthermore, one end of the first movable fireproof ring extends between the aluminum silicate plate and the stainless steel surface aluminum silicate composite plate, the first movable fireproof ring is fitted with the stainless steel surface aluminum silicate composite plate, the first movable fireproof ring and the stainless steel surface aluminum silicate composite plate are fixed by stainless steel dovetail nails, and the dovetail nail installation hole on the first movable fireproof ring is larger than the dovetail nail diameter, a gasket with a radius larger than the dovetail nail installation hole is installed between the first movable fireproof ring and the dovetail nail, and the first movable fireproof ring and the stainless steel surface aluminum silicate composite plate are fixed by dovetail nails.

[0015] The advantages of the present invention are: the installation hole of the converter transformer bushing opened on the fireproof sealing plate and the converter transformer bushing are densely filled with multiple layers by means of the aluminum silicate fiber blanket, the aluminum silicate plate and the first movable fireproof ring, thereby enhancing the structural strength of the converter transformer bushing hole sealing;

[0016] The aluminum silicate fiber blanket and the fireproof plugging plate are sealed once through the second movable fireproof ring, and then the outer side of the fireproof plugging plate, the outer side of the second movable fireproof ring and the outer wall of the converter transformer bushing are sealed for the second time through the silicone rubber plate, so as to improve the overall waterproof, fireproof, smokeproof and heat-insulating performance of the plugging system, and enhance the overall fire resistance of the plugging system, without smoke leakage and smoke channeling, thus ensuring the integrity of the plugging system, and easy processing, convenient construction, maintenance and replacement;

[0017] The first movable fireproof ring, the second movable fireproof ring and the fireproof sealing plate are fixed by stainless steel dovetail nails, and their positions can be flexibly adjusted to adapt to small displacements of the converter transformer bushing while ensuring the fireproof performance of the flexible sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention;

[0019] Figure 2 and Figure 3 It is a schematic diagram of a partially enlarged structure of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0021] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. The following embodiments can enable technicians in this field to understand the present invention more comprehensively, but the present invention is not limited to the scope of the embodiments.

[0022] like Figure 1 , Figure 2 and Figure 3 As shown, this specific embodiment adopts the following technical scheme: including explosion-proof plugging and fire-proof plugging sealed and installed on the firewall of the converter transformer valve hall, the explosion-proof plugging plate 15 and the fire-proof plugging plate 1 are provided with converter transformer bushing mounting holes matching the converter transformer bushing 2, the converter transformer bushing 2 is obliquely installed in the converter transformer bushing mounting hole, and flexible plugging is required between the converter transformer bushing 2 and the converter transformer bushing mounting hole to ensure the strength and sealing of the entire plugging system, the explosion-proof plugging plate 15 has an explosion-proof stainless steel panel 16 and an explosion-proof stainless steel keel, the fire-proof plugging plate 1 has a stainless steel surface rock wool composite plate 11 and a stainless steel surface aluminum silicate composite plate 12, the stainless steel surface aluminum silicate composite plate 12 is arranged on the fire-facing side, and an air layer structure 13 is added between the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12 through the stainless steel keel to ensure fire and explosion resistance.

[0023] The explosion-proof stainless steel keel is welded from non-magnetized stainless steel square tubes, the explosion-proof stainless steel panel 16 is connected to the explosion-proof stainless steel keel with stainless steel bolts, the explosion-proof stainless steel keel is fixed to the wall with stainless steel bolts, a movable explosion-proof ring 17 is arranged at the installation hole of the converter transformer bushing opened on the explosion-proof stainless steel panel 16, the dovetail nail installation hole on the movable explosion-proof ring 17 is larger than the diameter of the dovetail nail, a gasket with a radius larger than the dovetail nail installation hole is installed between the movable explosion-proof ring 17 and the dovetail nail, the movable explosion-proof ring 17 is fixed to the explosion-proof stainless steel panel 16 by dovetail nails, and the movable explosion-proof ring 17 and the converter transformer bushing are sealed and fixed with fireproof sealant 7.

[0024] Specifically, the technical parameters of the stainless steel surface rock wool composite board 11 material are as follows:

[0025]

[0026] The technical parameters of stainless steel surface aluminum silicate composite plate 12 material are as follows:

[0027]

[0028] Aluminum silicate fiber blankets 3 are densely filled between the stainless steel surface rock wool composite plate 11 and the outer tube wall of the converter transformer bushing 2 at the installation hole of the converter transformer bushing, and between the stainless steel surface aluminum silicate composite plate 12 and the outer tube wall of the converter transformer bushing 2. Aluminum silicate plates 4 and the first movable fireproof ring 5 are filled between the two aluminum silicate fiber blankets 3. The multi-layer dense filling enhances the structural strength of the converter transformer bushing hole plugging; the dovetail nail installation hole on the first movable fireproof ring 5 is larger than the dovetail nail diameter, and a gasket with a radius larger than the dovetail nail installation hole is installed between the first movable fireproof ring 5 and the dovetail nail. The first movable fireproof ring 5 and the stainless steel surface aluminum silicate composite plate 11 are fixed by dovetail nails; the aluminum silicate plate 4 extends to An air layer structure 13 is added between the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12, and one side of the aluminum silicate plate 4 is fitted with the stainless steel surface rock wool composite plate 11; one end of the first movable fireproof ring 5 extends between the aluminum silicate plate 4 and the stainless steel surface aluminum silicate composite plate 12, and the first movable fireproof ring 5 is fitted with the stainless steel surface aluminum silicate composite plate 12, the first movable fireproof ring 5 and the stainless steel surface aluminum silicate composite plate 12 are fixed by stainless steel dovetail nails 8, and the first movable fireproof ring 5 and the fireproof sealing plate 1 are fixed by stainless steel dovetail nails 8, and the position can be flexibly adjusted to adapt to the small displacement of the converter bushing 2 while ensuring the fireproof performance of the flexible sealing.

[0029] The technical parameters of aluminum silicate fiber blanket 3 material are as follows:

[0030]

[0031] The technical parameters of aluminum silicate plate 4 material are as follows:

[0032]

[0033] The outer sides of the two aluminum silicate fiber blankets 3 are respectively sealed with the outer sides of the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12 of the fireproof sealing plate 1 by a second movable fireproof ring 6, and the ends of the second movable fireproof ring 6 are sealed with the stainless steel surface rock wool composite plate 11, the stainless steel surface aluminum silicate composite plate 12, and the converter bushing 2 by a fireproof sealant 7, and the second movable fireproof ring 6 is fixed to the fireproof sealing plate 1 by a stainless steel dovetail nail 8. The aluminum silicate fiber blanket 3 and the fireproof sealing plate 1 are first sealed by the second movable fireproof ring 6, and the second movable fireproof ring 6 is fixed to the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12 by stainless steel dovetail nails 8, and the position can be flexibly adjusted to adapt to the small displacement of the converter bushing 2 while ensuring the fireproof performance of the flexible plugging.

[0034] The technical parameters of fireproof sealant 7 material are as follows:

[0035]

[0036] The stainless steel surface rock wool composite plate 11 of the fireproof sealing plate 1, the outer side of the stainless steel surface aluminum silicate composite plate 12, the outer side of the second movable fireproof ring 6 and the outer wall of the converter transformer bushing 2 are integrally wrapped and sealed by the silicone rubber plate 10, and the corners of the silicone rubber plate 10 and the joints with the converter transformer bushing 2, the second movable fireproof ring 6, the stainless steel surface rock wool composite plate 11, and the stainless steel surface aluminum silicate composite plate 12 are all sealed by fireproof sealant 7, and the silicone rubber plate 10 wrapped around the outside of the converter transformer bushing 2 is fixed by a stainless steel clamp 14, and the silicone rubber plate 10 wrapped around the outside of the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12 are fixed to the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12 by stainless steel dovetail nails 8 and stainless steel pressure plates 9 respectively.

[0037] The stainless steel surface rock wool composite plate 11, the outer side of the stainless steel surface aluminum silicate composite plate 12, the outer side of the second movable fireproof ring 6 and the outer wall of the converter transformer bushing 2 are sealed for the second time through the silicone rubber plate 10, so as to improve the overall waterproof, fireproof, smoke-proof and heat-insulating performance of the sealing system, enhance the overall fire resistance of the sealing system, prevent smoke leakage and smoke cross-flow, and ensure the integrity of the sealing system. The second movable fireproof ring 6 and the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12 are fixed by stainless steel dovetail nails 8, and the position can be flexibly adjusted to adapt to the small displacement of the converter transformer bushing 2 while ensuring the fireproof performance of the flexible plugging.

[0038] The technical parameters of the silicone rubber sheet 10 material are as follows:

[0039]

[0040] The flexible plugging design of the hole of the valve side casing of the converter transformer valve hall is a multi-layer structure from the inside to the outside of the valve hall, which is sequentially: using a silicone rubber plate 10 for external plugging, and sealing the edge with a fireproof sealant 7; using a movable second movable fireproof ring 6 for plugging, and the second movable fireproof ring 6 is fixed by a stainless steel dovetail nail 8; using an aluminum silicate fiber blanket 3 to densely fill the stainless steel surface rock wool composite plate 11 and the converter transformer bushing 2; using an aluminum silicate plate 4 to densely fill the air layer structure 13 added between the converter transformer bushing 2 and the stainless steel surface rock wool composite plate 11 and the stainless steel surface aluminum silicate composite plate 12; using a movable first movable fireproof ring 5 to be fixed on the converter transformer bushing 2; using an aluminum silicate fiber blanket 3 to densely fill the stainless steel surface aluminum silicate composite plate 12 and the converter transformer bushing 2; using a movable second movable fireproof ring 6 for plugging, and the second movable fireproof ring 6 is fixed by a stainless steel dovetail nail 8; using a silicone rubber plate 10 for plugging, and sealing the edge with a fireproof sealant 7. This structure can not only meet the daily dustproof, waterproof and sealing requirements, but also prevent the spread of flames and smoke when a fire occurs, achieving the equivalent fireproof performance of the sealing system and the firewall, and the fire resistance limit is not less than 3h.

[0041] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A flexible plugging structure for the hole of the bushing on the valve side of the converter transformer valve hall, comprising an explosion-proof plugging plate and a fire-proof plugging plate which are sealed and installed on the fire wall of the converter transformer valve hall, the explosion-proof plugging plate and the fire-proof plugging plate are provided with a converter transformer bushing mounting hole which matches the converter transformer bushing, the converter transformer bushing is obliquely installed in the converter transformer bushing mounting hole, and is characterized in that: The explosion-proof plugging plate has an explosion-proof stainless steel panel and an explosion-proof stainless steel keel; the fireproof plugging plate has a stainless steel surface rock wool composite plate and a stainless steel surface aluminum silicate composite plate, and an air layer structure is added between the stainless steel surface rock wool composite plate and the stainless steel surface aluminum silicate composite plate through the stainless steel keel; The explosion-proof stainless steel keel is welded by non-magnetized stainless steel square tubes, the explosion-proof stainless steel panel and the explosion-proof stainless steel keel are connected by stainless steel bolts, the explosion-proof stainless steel keel is fixed to the wall by stainless steel bolts, and a movable explosion-proof ring is provided at the installation hole of the converter transformer bushing opened on the explosion-proof stainless steel panel; The hole wall of the converter transformer bushing installation hole and the converter transformer bushing are densely filled with an aluminum silicate fiber blanket, an aluminum silicate plate and a first movable fireproof ring. The junction between the outer side of the aluminum silicate fiber blanket and the outer side of the fireproof sealing plate is sealed by a second movable fireproof ring. The end of the second movable fireproof ring and the junction between the fireproof sealing plate and the converter transformer bushing are sealed by fireproof sealant, and the second movable fireproof ring and the fireproof sealing plate are fixed by stainless steel dovetail nails. The outer side of the fireproof sealing plate, the outer side of the second movable fireproof ring and the outer wall of the converter transformer bushing are integrally wrapped and sealed by the silicone rubber plate, and the joints between the corners of the silicone rubber plate and the converter transformer bushing, the second movable fireproof ring and the fireproof sealing plate are all sealed by fireproof sealant, and the silicone rubber plate wrapped around the outside of the converter transformer bushing is fixed by a stainless steel clamp, and the silicone rubber plate wrapped around the outside of the fireproof sealing plate is fixed to the fireproof sealing plate by stainless steel dovetail nails and a stainless steel pressure plate.

2. The flexible sealing structure for casing holes on the valve side of a converter transformer valve hall according to claim 1 is characterized in that: A movable explosion-proof ring is arranged at the converter transformer bushing installation hole opened on the explosion-proof stainless steel panel, the dovetail nail installation hole on the movable explosion-proof ring is larger than the diameter of the dovetail nail, a gasket with a radius larger than the dovetail nail installation hole is installed between the movable explosion-proof ring and the dovetail nail, the movable explosion-proof ring and the explosion-proof stainless steel panel are fixed by the dovetail nails, and the movable explosion-proof ring and the converter transformer bushing are sealed and fixed by using fire-proof sealant.

3. The flexible sealing structure for casing holes on the valve side of a converter transformer valve hall according to claim 1 is characterized in that: Aluminum silicate fiber blankets are densely filled between the stainless steel surface rock wool composite plate and the outer tube wall of the converter transformer bushing at the installation hole of the converter transformer bushing, and between the stainless steel surface aluminum silicate composite plate and the outer tube wall of the converter transformer bushing. Aluminum silicate plates and the first movable fireproof ring are filled between the two aluminum silicate fiber blankets.

4. The flexible sealing structure for casing holes on the valve side of a converter transformer valve hall according to claim 3 is characterized in that: The aluminum silicate plate extends into the air layer structure added between the stainless steel surface rock wool composite plate and the stainless steel surface aluminum silicate composite plate, and one side of the aluminum silicate plate is in contact with the stainless steel surface rock wool composite plate.

5. The flexible plugging structure for casing holes on the valve side of a converter transformer valve hall according to claim 3 is characterized in that: One end of the first movable fireproof ring extends between the aluminum silicate plate and the stainless steel surface aluminum silicate composite plate, the first movable fireproof ring is fitted with the stainless steel surface aluminum silicate composite plate, the first movable fireproof ring and the stainless steel surface aluminum silicate composite plate are fixed by stainless steel dovetail nails, and the dovetail nail installation hole on the first movable fireproof ring is larger than the dovetail nail diameter, a gasket with a radius larger than the dovetail nail installation hole is installed between the first movable fireproof ring and the dovetail nail, and the first movable fireproof ring and the stainless steel surface aluminum silicate composite plate are fixed by dovetail nails.

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