Double-adjustment magnetic pre-tightening explosion door device

Abstract

The invention discloses a double-adjustment magnetic pre-tightening anti-explosion door device, and relates to the technical field of boiler anti-explosion doors, the double-adjustment magnetic pre-tightening anti-explosion door device comprises a boiler pipeline and a mounting bent seat welded on the boiler pipeline, the mounting bent seat is connected with a mounting seat, and the mounting seat is connected with a connecting cover; the device further comprises a first gland and a second gland. The first gland abuts against the opening edge of the mounting base, and a spring is arranged between the first gland and the top wall of the connecting cover. The second gland is arranged on the outer top wall of the connecting cover and connected with a magnet fixed to the outer top wall of the connecting cover in a magnetic attraction mode. The second gland is in threaded connection with a bolt, and the bolt penetrates through the top wall of the connecting cover to abut against the vertical rod on the top face of the first gland. The magnetic attraction force of the second gland and the magnet acts on the first gland through the bolt and the vertical rod, and then it is guaranteed that the first gland is stably sealed before the pressure of the pressure relief channel reaches the detonation threshold value. According to the anti-explosion door, the elastic force of the spring and the pre-tightening force of the magnet bolt are combined, so that the pressure relief channel can keep stable sealing when the detonation threshold value is not reached, leakage is effectively prevented, and the reliability of the anti-explosion door is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of boiler explosion doors, and more particularly to a double-adjustment magnetic pre-tightening explosion door device. BACKGROUND

[0002] During operation, a boiler device may explode due to fuel accumulation, ignition failure or improper operation, causing an overpressure risk. If the traditional boiler structure cannot quickly release pressure, it may cause serious damage to the equipment and even casualties. The explosion door, as a pressure relief device, has emerged as the times require.

[0003] Traditional explosion doors can be divided into gravity type, spring type and bursting disc type explosion doors according to structure. The gravity type and spring type explosion doors are simple in structure but are easily affected by ash corrosion, and have poor sealing performance and reset reliability. The bursting disc type explosion door cannot be repeatedly detonated and needs to be replaced regularly, resulting in high maintenance costs. Figure 1 As shown in FIG. 1, before the internal pressure of the coal mill reaches the detonation threshold, the traditional spring type explosion door has a leakage risk due to the gradual increase in the internal pressure of the coal mill and the gradual decrease in the pressure difference on both sides of the gland.

[0004] Therefore, how to solve the problem that the traditional spring type explosion door cannot have both good sealing performance and sensitivity, so as to achieve the advantages of repeated detonation, good sealing, accurate detonation and rapid explosion relief, is a technical problem that needs to be solved by those skilled in the art. SUMMARY

[0005] Therefore, the present application provides a double-adjustment magnetic pre-tightening explosion door device to solve the above technical problems.

[0006] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0007] A double-adjustment magnetic pre-tightening explosion door device comprises a boiler pipeline and a mounting elbow seat welded on the boiler pipeline, a mounting seat is connected to the mounting elbow seat through bolt fastening, and a connecting cover is connected to the mounting seat through bolt fastening.

[0008] A first gland is located inside the connecting cover and abuts with the opening edge of the mounting seat, so as to block the pressure relief channel of the boiler pipeline, and a spring is arranged between the first gland and the top wall of the connecting cover.

[0009] The second grommet is arranged on the outer top wall of the connecting cover and is magnetically attracted to the magnet fixed on the outer top wall of the connecting cover; the second grommet is threadedly connected with a bolt, the bolt penetrates through the top wall of the connecting cover and abuts against the vertical rod on the top surface of the first grommet; the magnetic attraction force between the second grommet and the magnet acts on the first grommet through the bolt and the vertical rod, thereby ensuring the stable sealing of the first grommet before the pressure in the pressure relief channel reaches the detonation threshold.

[0010] Through the above technical solution, the first grommet is abutted against the opening edge of the mounting seat to block the pressure relief channel, and the elastic force of the spring and the pre-tightening force of the magnet bolt are combined, so that the pressure relief channel can be stably sealed when the detonation threshold is not reached, effectively preventing leakage and improving the reliability of the explosion-proof door. The second grommet is magnetically connected to the magnet and acts on the first grommet through the bolt and the vertical rod. This combination of magnetic pre-tightening and mechanical adjustment can flexibly adjust the pre-tightening force, so that the explosion-proof door can only open when the pressure reaches the precise detonation threshold, avoiding untimely or premature pressure relief due to misoperation or insensitivity, thereby improving the accuracy of pressure relief while ensuring safety.

[0011] Preferably, in the above-mentioned double-adjustment magnetic pre-tightening explosion-proof door device, the magnet is detachably connected to the outer top wall of the connecting cover by a screw. The magnet is detachably connected to the outer top wall of the connecting cover by a screw, which facilitates the replacement of the magnet when necessary to restore or adjust its magnetism, thereby flexibly adjusting the size of the magnetic pre-tightening force according to actual use conditions and requirements, enhancing the maintainability and adaptability of the explosion-proof door, and eliminating the need to replace the entire device due to magnet failure or weakened magnetism, effectively reducing the use cost and maintenance difficulty.

[0012] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, the vertical rod is fixed at the center of the top surface of the pressure cover one, a lower sleeve is arranged coaxially and spaced apart outside the vertical rod, the lower sleeve is fixed to the top surface of the pressure cover one, an upper sleeve is arranged in close contact with the connecting cover, the upper sleeve is arranged outside the bolt, and the top end of the upper sleeve is provided with a pressing plate abutting against the inner top wall of the connecting cover; both ends of the spring are sleeved on the upper sleeve and the lower sleeve, and the spring is tightly pressed between the pressure cover one and the pressing plate. The vertical rod, the lower sleeve and the upper sleeve are arranged, the spring is sleeved on the upper sleeve and the lower sleeve and is tightly pressed between the pressure cover one and the pressing plate, so that the spring is more uniform and stable in stress during pre-tightening and explosion relief, the sealing failure or abnormal explosion relief caused by deformation or uneven stress of the spring is avoided, the structural stability and action reliability of the entire device are enhanced, and the service life of the equipment is prolonged. The vertical rod is fixed at the center of the top surface of the pressure cover one, the lower sleeve is arranged coaxially and spaced apart outside the vertical rod, and the upper sleeve is arranged in close contact with the connecting cover and abuts against the inner top wall of the connecting cover. This structural layout makes the pre-tightening force between the pressure cover one and the pressing plate more reasonable under the action of the spring, improves the stability and reliability of the entire device, and facilitates accurate adjustment of the compression amount of the spring, thereby further optimizing the pre-tightening effect.

[0013] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, a plurality of evenly distributed adjusting bolts are threadedly connected to the top wall of the connecting cover, the adjusting bolts pass through the relief holes formed in the pressure cover two, and the bottom ends of the adjusting bolts abut against the top surface of the pressing plate. The position of the pressing plate can be fine-tuned by the extension and retraction of the adjusting bolts, and the compression amount of the spring can be accurately controlled, so as to accurately adjust the explosion threshold of the explosion door, so that the explosion door can better adapt to the strict requirements of pressure control under different working conditions, improve the universality and flexibility of the equipment, and reduce the safety risks caused by improper setting of the pressure threshold.

[0014] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, the upper sleeve extends to the top of the vertical rod and is in sliding cooperation with the top of the vertical rod. The upper sleeve extends to the top of the vertical rod and is in sliding cooperation with the top of the vertical rod. This sliding cooperation structure enables the vertical rod and the upper sleeve to slide relative to each other during the action of the explosion door (such as the pressure cover one being lifted up during explosion relief or the pressure cover one being pressed down during reset), so as to better adapt to the dynamic displacement of the pressure cover one, ensure that the spring always maintains a good stress state and stable spring force output during the entire action process, further enhance the stability and reliability of the explosion door during the working process, and avoid structural damage or functional abnormalities caused by rigid interference between components.

[0015] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, a sealing ring is embedded in the opening edge of the mounting seat, and the sealing ring is in abutting connection with the gland. The sealing performance of the explosion door is further enhanced, and the leakage of gas or liquid can be effectively prevented in harsh working environments such as high pressure and corrosion, so that the explosion door can maintain a good sealing state before reaching the explosion threshold, and the safety and reliability of the explosion door are improved, and the safety hidden danger caused by leakage is reduced.

[0016] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, the mounting seat is connected to the mounting elbow seat and the connecting cover through flange structures on both sides. The flange connection is a connection mode with high strength, good sealing performance, simple structure and convenient installation and disassembly. This connection mode makes the connection of the whole device more stable, enhances the strength and reliability of the overall structure, and also facilitates quick replacement or maintenance of each component when needed, improves the maintenance efficiency of the equipment, and reduces the maintenance cost.

[0017] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, a sealing gasket is arranged on the flange connection surface between the mounting seat and the mounting elbow seat. The sealing effect of the connection is further enhanced to prevent leakage caused by poor sealing at the connection, so that the explosion door can always maintain a good sealing state during operation, and the safety and reliability of the explosion door are improved. Especially in high-temperature, high-pressure or hazardous medium handling occasions, the importance of this sealing measure is more prominent.

[0018] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, a cover shell is fixedly connected to the outer top wall of the connecting cover through screws, and the gland No. 2 is arranged in the cover shell. The cover shell fixedly connected to the outer top wall of the connecting cover houses the gland No. 2, which provides additional physical protection for the gland No. 2, prevents the gland No. 2 from being disturbed or damaged by external environmental factors (such as dust, debris, impact, etc.), and also helps to maintain the stability of the magnetic attraction connection between the gland No. 2 and the magnet, ensuring the normal operation and reliability of the explosion door in various complex environments, and prolonging the service life of the equipment.

[0019] Preferably, in the above-mentioned double-adjustable magnetic pre-tightening explosion door device, a lifting lug is fixedly arranged on the top surface edge of the connecting cover. The lifting lug fixedly arranged on the top surface edge of the connecting cover provides convenience for carrying and installation, and facilitates hoisting operation using hoisting equipment, so that the carrying and positioning during installation and maintenance of the explosion door can be more efficient and safe, improving the work efficiency, reducing the labor cost and labor intensity, and also reducing the risk of equipment damage caused by improper carrying.

[0020] Compared with the prior art, the double-adjusting magnetic pre-tightening explosion door device has the following beneficial effects:

[0021] 1. The sealing performance is significantly improved: through the abutment of the pressure cover 1 and the opening edge of the mounting seat, combined with the sealing ring and the sealing washer, and the magnetic attraction force of the magnet and the spring force of the pressure cover 2, the explosion door can be stably sealed when the explosion threshold is not reached, effectively preventing leakage.

[0022] 2. The sensitivity and safety are enhanced: the magnetic attraction connection of the magnet and the pressure cover 2, combined with the elastic force of the spring and the adjusting force of the bolt, optimizes the pre-tightening force and the explosion threshold, so that the explosion door can be quickly opened to relieve pressure when the pipeline pressure increases sharply, avoiding leakage and safety risks.

[0023] 3. The adaptability and flexibility are improved: the magnet is detachably connected through the screw, and the adjusting screw of the connecting cover top wall can adjust the spring compression amount, so that the magnetic pre-tightening force and the explosion threshold can be flexibly adjusted, making the explosion door suitable for different pressure working conditions, and enhancing the universality and flexibility.

[0024] 4. The pressure relief efficiency is greatly improved: compared with the traditional spring type explosion door, when relieving pressure, the pressure cover 1 can push the bolt to separate the pressure cover 2 from the magnet, the magnetic force attenuation increases the pressure cover 1 stroke, ensuring efficient pressure relief, avoiding insufficient pressure relief, and significantly improving the pressure relief efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0026] Figure 1 The drawing is a structure sectional view of the existing spring type explosion door provided by the present application;

[0027] Figure 2 The drawing is a whole structure sectional view of the double-adjusting magnetic pre-tightening explosion door device provided by the present application;

[0028] Figure 3 The drawing is a partial structure sectional view of the double-adjusting magnetic pre-tightening explosion door device provided by the present application;

[0029] Figure 4 The drawing is a structure stress schematic diagram of the double-adjusting magnetic pre-tightening explosion door device provided by the present application.

[0030] Among them:

[0031] 1 - boiler pipe; 2 - mounting bend seat; 3 - mounting seat; 4 - connecting cover; 5 - pressure cover one; 6 - pressure cover two; 7 - spring; 8 - magnet; 9 - bolt; 10 - vertical rod; 11 - lower sleeve; 12 - upper sleeve; 13 - pressing plate; 14 - adjusting bolt; 15 - avoiding hole; 16 - sealing ring; 17 - sealing washer; 18 - cover; 19 - lifting lug; 20 - pressure cover. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0033] Referring to the drawings Figure 2 to the drawings Figure 3 The embodiments of the present application disclose a kind of double-regulation magnetic pre-tightening explosion door device, comprising: boiler pipe 1 and welding on the mounting bend seat 2 of boiler pipe 1, mounting bend seat 2 is connected with mounting seat 3 by bolt fastening, mounting seat 3 is connected with connecting cover 4 by bolt fastening on the opening edge of mounting seat 3;Still comprising:

[0034] pressure cover one 5, pressure cover one 5 is located in the inside of connecting cover 4, pressure cover one 5 is abutted with the opening edge of mounting seat 3, for plugging the pressure relief channel of boiler pipe 1, spring 7 is arranged between pressure cover one 5 and the top wall of connecting cover 4;

[0035] pressure cover two 6, pressure cover two 6 is arranged on the outer top wall of connecting cover 4, and is magnetically connected with the magnet 8 fixed on the outer top wall of connecting cover 4;Pressure cover two 6 is screw-connected with bolt 9, bolt 9 is abutted with vertical rod 10 on the top surface of pressure cover one 5 by penetrating the top wall of connecting cover 4;The magnetic attraction of pressure cover two 6 and magnet 8 acts on pressure cover one 5 through bolt 9 and vertical rod 10, to ensure the stable sealing of pressure cover one 5 before the pressure of pressure relief channel reaches the detonation threshold.

[0036] In order to further optimize the above technical solutions, magnet 8 is detachably connected on the outer top wall of connecting cover 4 by screw.

[0037] In order to further optimize the above technical solutions, vertical rod 10 is fixed on the top surface center of pressure cover one 5, lower sleeve 11 is arranged on the outside of vertical rod 10 in coaxial interval, lower sleeve 11 is fixed with the top surface of pressure cover one 5, connecting cover 4 is arranged with upper sleeve 12, upper sleeve 12 is arranged on the outside of bolt 9, upper sleeve 12 has pressing plate 13 on the top end, which is abutted with the inner top wall of connecting cover 4;Both ends of spring 7 are sleeved on upper sleeve 12 and lower sleeve 11, and are tightly pressed between pressure cover one 5 and pressing plate 13.

[0038] In order to further optimize the above technical solutions, the top wall of the connecting cover 4 is threadedly connected with a plurality of evenly distributed adjusting bolts 14, the adjusting bolts 14 pass through the avoiding holes 15 arranged on the pressure cover two 6, and the bottom ends of the adjusting bolts 14 abut against the top surface of the pressing plate 13, the adjusting bolts 14 are used for adjusting the pressing plate 13, and then the elastic force of the spring 7 is adjusted.

[0039] In order to further optimize the above technical solutions, the sleeve 12 extends to the top of the vertical rod 10 and is in sliding fit with the top of the vertical rod 10.

[0040] In order to further optimize the above technical solutions, the opening edge of the mounting seat 3 is embedded with a sealing ring 16, and the sealing ring 16 is in abutting fit with the pressure cover one 5.

[0041] In order to further optimize the above technical solutions, the two sides of the mounting seat 3 are connected with the mounting elbow seat 2 and the connecting cover 4 through the flange structures.

[0042] In order to further optimize the above technical solutions, the mounting seat 3 and the flange connecting surface of the mounting elbow seat 2 are provided with a sealing washer 17.

[0043] In order to further optimize the above technical solutions, the outer top wall of the connecting cover 4 is fixedly connected with a cover shell 18 through screws, and the cover shell 18 covers the pressure cover two 6 inside.

[0044] In order to further optimize the above technical solutions, the top surface edge of the connecting cover 4 is fixedly connected with a lifting lug 19.

[0045] The pressure cover two 6 converts the magnetic attraction force of the magnet 8 to the pressure cover two 6 into the pressure of the bolt 9 to the pressure cover one 5 through the threaded connection of the bolt 9, so as to achieve the sealing and pre-tightening effect. When the double-adjusting magnetic pre-tightening explosion door provided in the embodiment is in normal operation, the pressure cover one 5 maintains sealing through the combined force of the body gravity, the spring elastic force and the strong magnet magnetic force transmitted by the bolt, as shown in Figure 4 When the double-adjusting magnetic pre-tightening explosion door is in explosion relief, the pressure cover one 5 is lifted by pressure to perform explosion relief.

[0046] Compared with Figure 1The traditional spring explosion door shown cannot adjust the explosion threshold, and the double-adjusting magnetic pre-tightening explosion door provided in the embodiment can adjust the explosion threshold of the double-adjusting magnetic pre-tightening explosion door by adjusting the compression amount of the spring 7 and adjusting the number of the magnet 8. Before the internal pressure of the coal mill reaches the explosion threshold, the traditional spring explosion door will have a risk of leakage due to the gradually increasing internal pressure of the coal mill and the gradually decreasing pressure difference between the two sides of the gland. The double-adjusting magnetic pre-tightening explosion door increases the magnetic pre-tightening structure, and uses the characteristics of the magnet 8 to ensure that the distance between the magnet 8 and the gland 6 does not change before the pipeline pressure reaches the explosion threshold, so as to ensure that the double-adjusting magnetic pre-tightening explosion door does not leak when the internal pressure of the coal mill increases. It can be said that the double-adjusting magnetic pre-tightening explosion door takes into account the sealing and sensitivity.

[0047] When an explosion occurs in the coal mill, the internal pressure of the pipeline increases sharply, and the explosion door opens to release pressure when the internal pressure exceeds the explosion threshold. When the traditional spring explosion door releases pressure, the spring pressure will increase with the opening of the explosion door, resulting in a decrease in the pressure difference between the two sides of the gland, a decrease in the travel of the gland, and a low and insufficient pressure relief efficiency of the explosion door. When the internal pressure of the pipeline reaches the explosion threshold, the double-adjusting magnetic pre-tightening explosion door provided in the embodiment opens to release pressure, the gland 5 pushes the bolt 9, the gland 6 and the magnet 8 connected with the bolt 9 are separated, the magnetic force of the magnet 8 rapidly attenuates, the attenuated magnetic force will be much greater than the additional pressure generated by the compression of the spring 7, at this time the pressure difference between the two sides of the gland 5 will increase, the travel of the gland 5 will increase, and the double-adjusting magnetic pre-tightening explosion door will efficiently release pressure until the internal pressure of the pipeline is lower than the spring pressure of the double-adjusting magnetic pre-tightening explosion door. The pressure relief threshold is the difference between the explosion threshold and the magnetic force of the magnet 8, and the pressure can be fully released below the explosion threshold.

[0048] The embodiment optimizes the structure to fundamentally solve the problem that the original spring explosion door cannot take into account the sealing and sensitivity, thereby ensuring that the gland is in an effective sealing state for a long time, and having important significance for solving the problems of poor sealing, poor sensitivity, high periodic replacement cost, and difficult maintenance of the current boiler explosion door, and having a wide application prospect.

[0049] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts of each embodiment can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the related parts can be referred to the method part.

[0050] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and that the appended claims are intended to cover all such modifications that do not depart from the true spirit and scope of the application. Therefore, the application is not limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A dual-adjustable magnetic pre-tightening explosion-proof door device, comprising: A boiler pipe (1) and a mounting elbow (2) welded to the boiler pipe (1), wherein a mounting seat (3) is fastened to the mounting elbow (2) by bolts, and a connecting cover (4) is fastened to the mounting seat (3) by bolts; characterized in that it further includes: Pressure cap one (5), the pressure cap one (5) is located inside the connecting cover (4), the pressure cap one (5) abuts against the opening edge of the mounting base (3) to block the pressure relief channel of the boiler pipe (1), and a spring (7) is provided between the pressure cap one (5) and the top wall of the connecting cover (4); The second pressure cover (6) is located on the outer top wall of the connecting cover (4) and is magnetically connected to the magnet (8) fixed on the outer top wall of the connecting cover (4). The second pressure cover (6) is threaded with a bolt (9), which passes through the top wall of the connecting cover (4) and abuts against the upright (10) on the top surface of the first pressure cover (5). The magnetic attraction between the second pressure cover (6) and the magnet (8) is applied to the first pressure cover (5) through the bolt (9) and the upright (10), thereby ensuring the stable sealing of the first pressure cover (5) before the pressure of the pressure relief channel reaches the detonation threshold.

2. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 1, characterized in that, The magnet (8) is detachably connected to the outer top wall of the connecting cover (4) by screws.

3. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 1, characterized in that, The upright (10) is fixed to the center of the top surface of the first pressure cover (5). The lower sleeve (11) is arranged coaxially on the outside of the upright (10). The lower sleeve (11) is fixed to the top surface of the first pressure cover (5). The upper sleeve (12) is attached to the connecting cover (4). The upper sleeve (12) is located on the outside of the bolt (9). The top end of the upper sleeve (12) has a pressure plate (13) that abuts against the inner top wall of the connecting cover (4). The two ends of the spring (7) are sleeved on the upper sleeve (12) and the lower sleeve (11) and pressed between the first pressure cover (5) and the pressure plate (13).

4. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 3, characterized in that, The top wall of the connecting cover (4) is threaded with multiple evenly distributed adjusting bolts (14). The adjusting bolts (14) pass through the clearance holes (15) opened on the second pressure cover (6), and the bottom end of the adjusting bolts (14) abuts against the top surface of the pressure plate (13).

5. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 3, characterized in that, The upper sleeve (12) extends to the top of the upright (10) and slides in cooperation with the top of the upright (10).

6. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 1, characterized in that, The mounting base (3) has a sealing ring (16) embedded in the opening edge, and the sealing ring (16) abuts against the pressure cap (5).

7. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 1, characterized in that, Both sides of the mounting base (3) are connected to the mounting elbow (2) and the connecting cover (4) via flange structures.

8. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 7, characterized in that, A sealing gasket (17) is provided on the flange connection surface between the mounting base (3) and the mounting elbow (2).

9. The dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 1, characterized in that, The outer top wall of the connecting cover (4) is fixedly connected to the cover (18) by screws, and the cover (18) covers the pressure cover (6) inside it.

10. A dual-adjustable magnetic pre-tightening explosion-proof door device according to claim 1, characterized in that, The top edge of the connecting cover (4) is fixed with a lifting lug (19).

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