An integrated anti-blast fireproof casing plugging system structure and a construction method thereof

Abstract

The present application relates to the technical field of power facility fire and explosion prevention, in particular to an integrated anti-explosion and fireproof bushing sealing system structure and a construction method thereof. The system is used for sealing the holes of the valve side bushing wall penetration of a converter transformer, and is designed in a multi-layer symmetrical integrated manner from inside to outside, comprising: a high-temperature vulcanized silicone rubber assembly as a sealing layer; a high-strength magnesium fireproof plate anchored on an anti-explosion and fireproof plate as an anti-explosion and fireproof ring layer; a composite filling layer formed by alternately filling with an aluminum silicate fiber blanket and a flexible expansion fireproof mortar; and a central aluminum silicate fiber blanket heat insulation layer. During construction, a double-node mechanical anchoring and flexible fireproof sealant combination method is used for sealing. The present application solves the problems of the prior art that the anti-explosion and fireproof performance is difficult to be considered together and the construction is complex, and provides an integrated sealing scheme with stable structure, durable sealing, standardized construction and excellent anti-explosion and fireproof performance.

Description

Technical Field

[0001] This invention relates to the field of fire and explosion protection technology for power facilities, and more specifically, to an integrated explosion-proof and fire-resistant bushing sealing system structure and its construction method. Background Technology

[0002] As a core component of DC power transmission, the converter transformer's valve-side bushing needs to pass through the valve hall firewall. Because internal faults in the converter transformer can induce explosive fires (fault arcs cause transformer oil to ignite, with instantaneous pressure exceeding 500 kPa and flame temperature reaching 1100℃), existing containment methods have some serious drawbacks:

[0003] Structural separation: The traditional solution adopts a dual-system separate design of "explosion-proof sealing layer and fireproof sealing layer" (such as fireproof bag and explosion-proof steel plate). Conventional bushing sealing does not have explosion-proof performance, only fire resistance performance. Its explosion-proof performance needs to be undertaken by the explosion-proof sealing. It is an explosion-proof and fireproof separation structure. This structure is complex, has a long installation cycle, and is not conducive to the relocation and maintenance of converter transformers.

[0004] Performance breakdown: Most fireproof materials (such as ordinary fireproof putty) lack explosion resistance and their structure disintegrates when subjected to impact;

[0005] Sealing failure: The bushing plug is the weakest part of the entire converter transformer valve hall valve side bushing plugging system. In the existing technology, only a simple plugging structure is used at the connection between the converter transformer bushing and the valve hall plug. Moreover, due to the vibration of the converter transformer during operation, the sealing performance of the bushing plug is not ideal. Once a fire or explosion accident occurs, the weak point at the bushing plug will become the main breakthrough point for the spread of fire, affecting the overall explosion-proof and fire-resistant performance and posing a safety hazard.

[0006] Therefore, there is an urgent need for a high-performance sealing structure that integrates explosion resistance and fire resistance. Summary of the Invention

[0007] The purpose of this invention is to provide an explosion-proof and fire-resistant integrated sleeve sealing system structure and its construction method to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, on the one hand, the present invention provides an explosion-proof and fire-resistant integrated bushing sealing system structure for sealing the hole through which the valve-side bushing of a converter transformer passes through the fire wall of the valve hall. This structure comprises seven layers from the inner to the outer side of the valve hall, including:

[0009] Inner and outer sealing layers: Pre-formed high-temperature vulcanized silicone rubber components are used. These components are integrally molded from a rubber sleeve tightly covering the casing and a rubber sheet tightly adhering to the surface of the explosion-proof fire-resistant board. The silicone rubber material must meet the following requirements: tensile strength ≥ 5 MPa, elongation at break ≥ 250%, and long-term operating temperature range -60℃ to 250℃. The sealing layers are fixed using a double-node mechanical anchoring method: on the casing side, non-magnetic stainless steel clamps are used to secure the rubber sleeve to the casing surface; on the explosion-proof fire-resistant board side, non-magnetic stainless steel strips are used in conjunction with expansion bolts to anchor the rubber sheet to the explosion-proof fire-resistant ring layer or the explosion-proof fire-resistant board. Flexible fire-resistant sealant is applied to all joints and corners to form a smooth R-angle transition, ensuring the continuity of the sealing interface under various operating conditions.

[0010] The inner and outer explosion-proof fire-resistant ring layers are made of high-strength magnesium fireproof board, machined to a thickness of 20±0.2mm, and reinforced internally with high-temperature resistant fiberglass mesh. This layer is firmly anchored to the explosion-proof fireproof board using high-density ST5.5×50 stainless steel dovetail nails (nail spacing not exceeding 150mm). Its main function is to act as the primary load-bearing component, directly bearing and dispersing the blast shock wave load, and transferring it to the robust fire wall, while simultaneously forming the first physical flame barrier.

[0011] The inner and outer composite filling layers employ a stacked structure of alternating, densely filled aluminum silicate fiber blankets and flexible expandable fireproof mortar. The bulk density of the aluminum silicate fiber blankets is 128±20 kg / m³. 3 With a thermal conductivity of ≤0.035W / (m·K) at room temperature, the flexible fireproof mortar has good plasticity and thermal expansion characteristics. This composite structure plays a role in buffering energy consumption and auxiliary heat insulation in the system.

[0012] The fourth layer is the central insulation layer, which is composed of high-purity aluminum silicate fiber blankets filled with highly dense material. As the core insulation area of ​​the entire sealing system, its main function is to block the axial conduction of high-temperature heat to the greatest extent possible.

[0013] This structure is mainly used for sealing the valve-side bushings in the converter transformer valve hall of ultra-high voltage converter stations. It meets daily dustproof, waterproof, and sealing requirements, and can also resist blast shock waves and prevent the spread of flames and smoke in the event of a converter transformer fault and deflagration fire. Under blast impact, the explosion-proof fire-resistant ring layer directly bears the load and distributes it, while the composite filling layer undergoes controllable deformation to absorb energy. Under fire conditions, the mortar in the composite filling layer expands and compacts the gaps when heated, forming a highly efficient heat insulation barrier together with the central insulation layer. The sealing layer compensates for displacement through elastic deformation, achieving a dynamic and durable seal.

[0014] Furthermore, the width and length of the explosion-proof fire-resistant ring layer are designed based on the diameter of the converter transformer valve side bushing. The fire-resistant ring must completely cover the holes in the valve hall sealing plate through which the converter transformer valve side bushing passes. Its performance parameters are as follows:

[0015] Flexural strength ≥ 8 MPa;

[0016] Impact strength ≥2kJ / m 2 ;

[0017] The fire resistance rating is non-combustible, Class A1.

[0018] On the other hand, the present invention provides a method for preparing an explosion-proof and fire-resistant integrated sleeve plugging system structure, comprising the following steps:

[0019] S1. Base surface treatment and positioning: Clean the surface of the sleeve and the holes in the firewall, check the dimensions, and determine the installation baseline for each layer.

[0020] S2. Install the explosion-proof fireproof ring layer: The prefabricated high-strength magnesium fireproof board fireproof ring is tightly attached to the walls on both sides of the explosion-proof fireproof board, and stainless steel dovetail nails are used to anchor it to the explosion-proof fireproof board with high density according to the design nail spacing (≤150mm).

[0021] S3, Filled with fire-resistant and heat-insulating material:

[0022] In the annular cavity formed by the inner fire baffle ring, an inner composite filling layer is constructed by alternating and densely filling a layer of aluminum silicate fiber blanket and a layer of flexible fireproof mortar.

[0023] In the middle of the annular cavity, high-purity aluminum silicate fiber blankets are compacted and filled in layers to form a central insulation layer.

[0024] On the outside, aluminum silicate fiber blankets and fireproof mortar are alternately filled in the same way to construct an outer composite filling layer.

[0025] S4. Install the sealing layer:

[0026] The prefabricated silicone rubber sealing assembly (rubber cylinder and rubber plate integrated) is inserted into the sleeve and placed on the inner and outer sides of the explosion-proof fireproof board respectively.

[0027] Use non-magnetic stainless steel clamps to secure the rubber sleeve to the sleeve;

[0028] Use non-magnetic stainless steel pressure strips and expansion bolts to press and anchor the perimeter of the rubber sheet to the explosion-proof fireproof ring layer or explosion-proof fireproof board; apply flexible fireproof sealant to all joints, corners and fastener edges and scrape to form a smooth R-corner transition.

[0029] S5. Final Inspection and Cleaning: Check the tightness of all fasteners, the flatness of the sealant layer, and the continuity of the adhesive joints. Clean the construction site.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] The integrated explosion-proof and fire-resistant sleeve sealing system and its construction method eliminate the weak interfaces of traditional schemes through integrated design, achieving an organic unity and mutual enhancement of explosion-proof (≥500kPa) and fire-resistant (≥4h hydrocarbon fire) performance. Actual measurements show that the system remains structurally intact after an explosion impact, and the temperature rise on the unexposed surface during the fire resistance test is far below the standard limit.

[0032] The functional layers work together to ensure stable explosion-proof and fire-resistant sealing performance. The silicone rubber seal and dual-node fixing method ensure the system's sealing durability under long-term vibration and temperature changes, reducing maintenance requirements.

[0033] The provided construction method has clear steps and simplified procedures, which helps ensure the compaction of each layer and the accuracy of installation. Compared with traditional multi-step construction, it can shorten the construction period and make the quality more controllable.

[0034] The high reliability and long lifespan of the results avoid potential major accident losses, reduce maintenance costs, and have significant economic benefits throughout the entire life cycle. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the sleeve sealing structure of Embodiment 1 of the present invention;

[0036] Figure 2 This is a diagram showing the overpressure distribution of shock waves greater than 100 kPa in Embodiment 2 of the present invention.

[0037] Figure 3 This is a diagram showing the overpressure distribution of shock waves less than 100 kPa in Embodiment 2 of the present invention.

[0038] Figure 4 This is a furnace temperature curve diagram of Embodiment 3 of the present invention;

[0039] Figure 5 This is an indoor pressure curve diagram of Embodiment 3 of the present invention;

[0040] Figure 6 This is a temperature rise curve of the unexposed side in Embodiment 3 of the present invention.

[0041] Meaning of each label in the diagram:

[0042] 1. Explosion-proof fire-resistant board; 2. High-temperature vulcanized silicone rubber components; 3. High-strength magnesium fireproof board; 4. Alumina silicate fiber blanket; 5. Fireproof putty; 6. Fireproof sealant; 7. Anchors. Detailed Implementation

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] The technical specifications of the QJ65HB, aluminum silicate fiber blanket, and fireproof mortar materials used in this invention are shown in Tables 1-3.

[0045] Table 1: Technical Specifications of QJ65HB

[0046]

[0047] Table 2: Density, thickness, melting point, and other properties of aluminosilicate fiber blankets

[0048]

[0049] Table 3: Technical Specifications of Fireproof Putty

[0050]

[0051] Example 1: This embodiment of the invention provides a casing plugging system structure that is both explosion-proof and fire-resistant, based on... Figure 1 As shown, from the inside to the outside of the valve hall, it includes, in sequence:

[0052] Inner sealing layer: made of high-temperature vulcanized silicone rubber component 2, which includes a rubber sleeve covering the sleeve and a rubber sheet tightly attached to the sealing surface.

[0053] Inner explosion-proof fireproof ring layer: high-strength magnesium fireproof board 3, anchored to the explosion-proof fireproof board 1 (as the base material for sealing the valve hall wall) with anchors 7 (such as dovetail nails).

[0054] Inner composite filling layer: Alternating dense filling of aluminum silicate fiber blanket 4 and flexible expandable fireproof mortar 5.

[0055] Central insulation layer: dense high-purity aluminum silicate fiber blanket.

[0056] Outer composite filler layer: same as inner layer.

[0057] Outer explosion-proof fireproof ring layer: same as the inner side.

[0058] Outer sealing layer: Same as inner side. The sealing layer is fixed by the double nodes of the clamp (fastening sleeve) and pressure strip (anchoring base) in the anchor (7), and all joints are sealed with flexible fireproof sealant 6 and made into smooth R corners.

[0059] The construction method includes the following steps:

[0060] 1. Install the inner sleeve sealing of the valve hall:

[0061] (1) Use a whole piece of aluminum silicate fiber blanket 4 to fill the sleeve around the perimeter, with a filling thickness of 60mm;

[0062] (2) Use aluminum silicate fiber blanket 4 and fireproof putty 5 alternately to fill the gap between the explosion-proof fireproof board 1 and the sleeve, filling it slightly higher than the surface of the explosion-proof fireproof board 1.

[0063] (3) On-site actual measurement of the sleeve dimensions and the position dimensions of other components (including conduits, oil pipes, lifting lugs, etc.); adjust the high-strength magnesium fireproof board 3 according to the actual measured dimensions;

[0064] (4) Trial installation of high-strength magnesium fireproof board 3 to ensure tight splicing of the high-strength magnesium fireproof board 3;

[0065] (5) Install high-strength magnesium fireproof board 3, fix the fireproof ring on the explosion-proof fireproof board 1 with ST5.5×50 stainless steel dovetail nails, apply fireproof sealant 6 to the joint between high-strength magnesium fireproof board 3 and sleeve, the joint of high-strength magnesium fireproof board 3 and the joint between high-strength magnesium fireproof board 3 and explosion-proof fireproof board 1, and compact it continuously without any breaks;

[0066] (6) Use high-temperature resistant insulating tubing to separately wrap the oil pipes, gas pipes, cables, etc. around the riser (if any), and tighten them with cable ties. Note that the distance between the oil pipes, gas pipes, cables, and other accessories and the metal surface of the explosion-proof fireproof board 1 and the keel should not be less than 30mm.

[0067] (7) Apply fireproof sealant 6 to the surface of the sleeve riser, wrap the flexible sealing tube in the high temperature vulcanized silicone rubber assembly 2 around the sleeve riser, and fix it with a clamp. The clamp is tightened using only the lower mounting hole, and the direction of the clamp's closing end is consistent with the closing direction of other sleeve clamps.

[0068] (8) Apply fireproof sealant 6 appropriately to the surface of the fireproof board, attach the flexible sealing rubber sheet in the high temperature vulcanized silicone rubber component 2 to the surface of the explosion-proof fireproof board 1, and use ST4.8×32 stainless steel dovetail nails to fix the stainless steel pressure strip to press the flexible sealing rubber sheet around the perimeter. Leave a clear gap of 5-10mm at the joint of the stainless steel pressure strip.

[0069] (9) At the joint between the flexible sealing tube and the flexible sealing sheet, fireproof sealant 6 is used to fill the joint, forming an R-angle at the root, and it is pressed firmly with a finger without any breaks.

[0070] (10) Use fire-retardant sealant 6 to seal the gaps where the pipes pass through;

[0071] (11) Apply fireproof sealant 6 to the edge of the sleeve riser surface and seal it around the perimeter, ensuring a continuous and uninterrupted application.

[0072] (12) Apply fireproof sealant 6 around the edge of the rubber sheet and seal along the joint of the rubber sheet, ensuring a continuous seal without any breaks.

[0073] 2. Install the grounding wire for the inner sleeve of the valve hall:

[0074] (1) Use 16mm between the strips 2 Use 200mm insulated copper stranded wire for bridging and secure with ST5.5×25 stainless steel dovetail screws. The terminals must be firmly crimped. For three-point connections, leave one gap (not bridging) as per the drawing requirements to maintain a disconnect. After bridging with a pressure strip, use 35mm... 2 Insulated copper stranded wire is led to the grounding copper busbar inside the valve hall, and 35mm wire is secured using M8×25 stainless steel hex bolts. 2 One end of the insulated copper stranded wire is fixed to the grounding copper busbar inside the valve hall, and the other end is fixed to the pressure strip with ST5.5×25 stainless steel dovetail nails. The wiring terminals must be tightened and must not be loosely connected. The position and direction of the grounding wire shall be in accordance with the drawings.

[0075] (2) Use 35mm 2 Insulated copper stranded wire connects the clamp to the grounding copper busbar. One end of the grounding wire is connected to the mounting hole on the upper side of the clamp and fixed with an M10×50 stainless steel hex bolt. It is only fixed to one side of the hole. An M8×25 stainless steel hex bolt is used to secure the 35mm diameter wire. 2 The other end of the insulated copper stranded wire is fixed to the grounding copper busbar inside the valve hall; the position and direction of the grounding wire shall be in accordance with the drawings.

[0076] (3) Use wire clips to fix the grounding wire. Install a wire clip every 400mm and fix it with ST4.8×19 stainless steel dovetail nails; the position and direction of the grounding wire shall be in accordance with the drawings.

[0077] III. Install the outer sleeve of the valve hall for sealing.

[0078] (1) Use aluminum silicate fiber blanket 4 and fireproof mortar 5 alternately to fill the gap between the explosion-proof fireproof board 1 and the sleeve from the outside of the valve hall, filling it slightly higher than the surface of the explosion-proof fireproof board 1.

[0079] (2) On-site actual measurement of the sleeve dimensions and the position dimensions of other components (including conduits, oil pipes, lifting lugs, etc.); adjust the high-strength magnesium fireproof board 3 according to the actual measured dimensions;

[0080] (3) Trial installation of high-strength magnesium fireproof board 3 to ensure tight splicing of high-strength magnesium fireproof board 3;

[0081] (4) Install high-strength magnesium fireproof board 3, fix the fireproof ring to the explosion-proof fireproof board 1 with ST5.5×50 stainless steel dovetail nails, apply fireproof sealant 6 to the joint between high-strength magnesium fireproof board 3 and sleeve, the joint of high-strength magnesium fireproof board 3 and the joint between high-strength magnesium fireproof board 3 and explosion-proof fireproof board 1, and compact it continuously without any breaks;

[0082] (5) Use high-temperature resistant insulating tubing to separately wrap the oil pipes, gas pipes, cables, etc. around the riser (if any), and tighten them with cable ties. Note that the distance between the oil pipes, gas pipes, cables, and other accessories and the metal surface of the explosion-proof fireproof board 1 should not be less than 30mm.

[0083] (6) Apply fireproof sealant 6 appropriately to the surface of the sleeve riser, wrap the flexible sealing rubber tube in the high temperature vulcanized silicone rubber assembly 2 around the sleeve riser, and fix it with a clamp. The clamp is tightened only using the lower mounting hole, and the direction of the clamp's closing end is consistent with the closing direction of other sleeve clamps.

[0084] (7) Apply fireproof sealant 6 appropriately to the surface of the fireproof board, attach the flexible sealing rubber sheet in the high temperature vulcanized silicone rubber component 2 to the surface of the explosion-proof fireproof board 1, and use ST4.8×32 stainless steel dovetail nails to fix the stainless steel pressure strip to press the flexible sealing rubber sheet around the perimeter. Leave a clear gap of 5-10mm at the joint of the stainless steel pressure strip.

[0085] (8) At the joint between the flexible sealing tube and the flexible sealing sheet, fireproof sealant 6 is used to fill the joint, forming an R-angle at the root, and then pressed firmly with a finger without any breaks.

[0086] (9) Use fire-retardant sealant 6 to seal the gaps where the pipes pass through;

[0087] (10) Apply fireproof sealant 6 to the edge of the sleeve riser surface and seal it around the perimeter, ensuring a continuous and uninterrupted application.

[0088] (11) Apply fireproof sealant 6 around the edge of the rubber sheet and seal along the joint of the rubber sheet, ensuring a continuous seal without any breaks.

[0089] IV. Install the grounding wire for sealing the outer sleeve of the valve hall.

[0090] (1) Use 16mm between the strips 2 Use 200mm insulated copper stranded wire for bridging and secure with ST5.5×25 stainless steel dovetail screws. The terminals must be firmly crimped. For three-point connections, leave one gap (not bridging) as per the drawing requirements to maintain a disconnect. After bridging with a pressure strip, use 35mm... 2 Insulated copper stranded wire is led to the grounding copper busbar outside the valve hall, and 35mm wire is secured using M8×25 stainless steel hex bolts. 2One end of the insulated copper stranded wire is fixed to the grounding copper busbar on the outside of the valve hall, and the other end is fixed to the pressure strip with ST5.5×25 stainless steel dovetail nails. The wiring terminals must be tightened and must not be loosely connected. The position and direction of the grounding wire shall be in accordance with the drawings.

[0091] (2) Use 35mm 2 Insulated copper stranded wire connects the clamp to the grounding copper busbar on the outside of the valve hall. One end of the grounding wire connects to the mounting hole on the upper side of the clamp and is fixed using M10×50 stainless steel hex bolts. It is only fixed to one side of the hole, and an M8×25 stainless steel hex bolt is used to secure the 35mm bolt. 2 The other end of the insulated copper stranded wire is fixed to the grounding copper busbar on the outside of the valve hall. The position and direction of the grounding wire shall be in accordance with the drawings.

[0092] (3) Use wire clips to fix the grounding wire. Install a wire clip every 400mm. Use M6×40 small yellow fish expansion bolts to fix it on the firewall. Use ST4.8×19 stainless steel dovetail nails to fix it on the board. The position and direction of the grounding wire shall be in accordance with the drawings.

[0093] Example 2: This example demonstrates the explosion-proof performance test of the construction method of the explosion-proof and fire-resistant integrated sleeve sealing system structure provided in Example 1 above.

[0094] Inspection basis: Q / IEM 3003.39-2011 Test method for explosion resistance and explosion relief performance of doors and windows.

[0095] Test conditions:

[0096] (1) Test column: 1000g PETN / TNT (mass ratio 1:1) column;

[0097] (2) The horizontal distance between the explosion-proof and fire-resistant integrated valve hall sealing system and the explosive charge detonation center is 1.68m;

[0098] (3) The peak pressure of the shock wave at 1.68m is 500kPa.

[0099] Test results: After being subjected to a shock wave with a peak pressure of 500 kPa, the explosion-proof and fire-resistant integrated valve hall sealing system showed no significant changes or damage to the explosion-facing and back-explosion-facing surfaces.

[0100] Specifically:

[0101] I. Test on the Overpressure-Distance Distribution of Explosion Shock Wave from a Explosive Column in Air

[0102] (1) Conditions for the drug column

[0103] Weight: 1000g (TNT / PETN=1:1); Dimensions: φ95mm×95mm; Density: 1.60g / cm³ 3 .

[0104] (2) Shock wave overpressure testing equipment

[0105] Pressure sensor (PCB Company, USA), model 137A21, 4 units in total; transient data acquisition instrument.

[0106] (3) Overpressure test of explosive charge shock wave

[0107] The experiment measured the shock wave overpressure generated at different locations when the explosive charge detonated in air. The pressure sensor measured the free field pressure. The overpressure distribution pattern of the shock wave is shown in [reference needed]. Figure 2 and Figure 3 The image ,in The TNT equivalent (1 kg) of the test column. This is the distance between the center of the propellant column and the center of the sensor (in meters).

[0108] II. Test Conditions for Explosion-Resistant and Fire-Resistant Integrated Valve Hall Sealing System

[0109] The distance between the center of the explosive charge and the center of the explosion-proof and fire-resistant integrated valve hall sealing system is 1.68m. Maintaining the explosive charge's detonation center and the sample center at the same horizontal height, based on the overpressure distribution pattern of shock waves in air, the peak pressure of the shock wave at 1.68m is 500kPa.

[0110] III. Test Results of the Explosion-Resistant and Fire-Resistant Integrated Valve Hall Sealing System

[0111] An explosion-proof test was conducted on the structure constructed using the method described in Example 1. According to relevant test methods, a 1000g equivalent explosive charge was detonated at a distance of 1.68m from the specimen, subjecting it to a shock wave with a peak value of approximately 500kPa. After the test, the system's blast-facing and blast-backing surfaces remained structurally intact, without significant deformation or damage, demonstrating that it meets the design explosion-proof requirements.

[0112] Example 3: This example demonstrates the fire resistance limit test of the construction method of the explosion-proof and fire-resistant integrated sleeve sealing system structure provided in Example 1 above.

[0113] I. Fire-resistant test specimen: The structure of this explosion-proof and fire-resistant integrated valve hall sealing system consists of flexible sealing, rigid sealing, edge sealing and penetration, etc. The specimen size is 3000mm×3000mm, and the diameter of the penetration is 1000mm.

[0114] II. Measurement Point Setup: Eight temperature measurement points are evenly distributed on the back-facing panel (recorded as T1-T8); one temperature measurement point is set at the back-facing panel joint (recorded as T9); two temperature measurement points are set at the edge of the back-facing small sealing layer (T10, T11); two temperature measurement points are set at the back-facing small sealing layer joint (T12, T13); two temperature measurement points are set at a distance of 25mm from the back-facing small sealing layer to the sleeve (T14, T15); two temperature measurement points are set at a distance of 25mm from the back-facing small sealing layer to the penetration (T16, T17).

[0115] III. Experimental Curve:

[0116] (1) The furnace temperature curve is the hydrocarbon temperature rise curve in GB / T26784-2011 "Optional and Additional Test Procedures for Fire Resistance Testing of Building Components" ( Figure 4 (2) The indoor pressure curve is the pressure curve located 500mm below the furnace top. Figure 5 ).

[0117] IV. Temperature rise on the unexposed side Figure 6 See Table 1.

[0118] Table 1: Temperature rise data of the unexposed side

[0119]

[0120] V. Test Results: The structure constructed using the method described in Example 1 was subjected to a fire resistance limit test. The test employed a standard hydrocarbon fire temperature rise curve, with multiple temperature measurement points set on the unexposed side of the specimen. After a 3-hour fire resistance test, no flame or smoke penetration occurred on the unexposed side of the system, the structure remained intact, and the temperature rise at each measurement point was far below the standard limit, demonstrating its excellent fire resistance performance.

[0121] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A bushing sealing system structure integrating explosion-proof and fire-resistant properties, used to seal the hole through which the valve-side bushing of a converter transformer passes through the fire wall of the valve hall, characterized in that, Along the inner to outer direction of the explosion-proof fire-resistant board (1), a multi-layer composite integrated symmetrical structure is adopted, including: The inner sealing layer and the outer sealing layer are made of a pre-formed high-temperature vulcanized silicone rubber assembly (2), which includes a rubber sleeve covering the sleeve and a rubber plate tightly attached to the sealing surface. The inner explosion-proof fireproof ring layer and the outer explosion-proof fireproof ring layer are located inside the sealing layer and are made of high-strength magnesium fireproof board (3) and fixed to the substrate by anchors (7); The inner composite filling layer and the outer composite filling layer are located on the inner side of the corresponding explosion-proof fireproof ring layer and are formed by alternating dense filling of aluminum silicate fiber blanket (4) and flexible expandable fireproof mortar (5). The central insulation layer is located between the two composite filling layers and is densely filled with aluminum silicate fiber blanket (4); The layers are combined into a continuous whole. The explosion-proof fireproof ring layer is constructed to withstand and disperse the explosion impact load. The composite filling layer is constructed to buffer and absorb energy and expand to fill the gaps when heated. The central heat insulation layer is constructed to block heat conduction. The sealing layer compensates for displacement through elastic deformation to achieve a durable seal. The inner sealing layer and the outer sealing layer are fixed by a double-node mechanical anchoring method. On the sleeve side, a non-magnetic stainless steel clamp is used to fasten the rubber tube to the sleeve surface. On the base side, a non-magnetic stainless steel pressure strip is used in conjunction with fasteners to anchor the rubber plate to the inner explosion-proof fireproof ring layer, the outer explosion-proof fireproof ring layer or the explosion-proof fireproof board (1). All joints and corners are filled with flexible fireproof sealant (6) to form a smooth transition.

2. The explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 1, characterized in that, The inner and outer explosion-proof fire-resistant ring layers are anchored to the explosion-proof fire-resistant board (1) by high-density arranged stainless steel dovetail nails. The board thickness is 20±0.2mm, and it meets the requirements of flexural strength ≥8MPa and impact strength ≥2kJ / m. 2 Its fire resistance rating is A1.

3. The explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 1, characterized in that, The bulk density of the aluminosilicate fiber blanket (4) is 128±20 kg / m³. 3 The thermal conductivity at room temperature is ≤0.035W / (m·K); the flexible expandable fireproof mortar (5) has good plasticity and thermal expansion characteristics.

4. The explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 1, characterized in that, The high-temperature vulcanized silicone rubber component (2) has a tensile strength ≥5MPa, an elongation at break ≥250%, and a long-term operating temperature range of -60℃ to 250℃.

5. A construction method for the explosion-proof and fire-resistant integrated sleeve sealing system structure according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Base surface treatment and positioning: Clean the surface of the sleeve and the holes of the explosion-proof fireproof board (1) to determine the installation baseline; S2. Install the explosion-proof fireproof ring layer: attach the prefabricated high-strength magnesium fireproof board (3) tightly to the surface of the substrate and fix it with anchors (7); S3. Filling with fire-resistant and heat-insulating materials: In the annular cavity inside the fire baffle, a composite filling layer is constructed by alternating and densely filling with aluminum silicate fiber blanket (4) and flexible fireproof mortar (5); in the middle of the annular cavity, aluminum silicate fiber blanket (4) is filled in layers to construct a central heat insulation layer. S4. Install the sealing layer: Slide the prefabricated high-temperature vulcanized silicone rubber component (2) into the sleeve and place it on both sides of the base. Use clamps to fasten the rubber tube to the sleeve, and use pressure strips to press the rubber sheet and anchor it to the base. Apply flexible fireproof sealant (6) to all joints and corners to form a smooth transition. S5. Final Inspection: Inspect the continuity of all fasteners, sealant layers, and adhesive joints.

6. The construction method of the explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 5, characterized in that, In S3, the construction of the composite filling layer is specifically as follows: first, a layer of aluminum silicate fiber blanket (4) is filled, then a layer of fireproof mortar (5) is applied, and so on alternately until it is densely filled and slightly higher than the surface of the explosion-proof fireproof ring layer.

7. The construction method of the explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 5, characterized in that, In step S4, before installing the sealing layer, the steps include: pre-applying fireproof sealant (6) to the surface of the sleeve riser and the substrate; filling the joint between the rubber tube and the rubber plate with fireproof sealant (6) and compacting it to form an R-angle; and continuously applying sealant to the edge of the rubber plate and the sealing edge.

8. The construction method of the explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 5, characterized in that, It also includes S6, installing grounding wires: using insulated copper stranded wires to connect the clamps and pressure strips to the grounding copper busbars inside and outside the valve hall, respectively, and to secure them reliably.

9. The construction method of the explosion-proof and fire-resistant integrated sleeve sealing system structure according to claim 5, characterized in that, In S2 or S4, the oil pipes, gas pipes or cables passing through the sealing area are individually wrapped with high-temperature resistant insulating tubes, and it is ensured that they are kept at a distance of not less than 30 mm from the metal surface.

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