Local underwater dry method welding drainage cover dynamic seal auxiliary device

Abstract

A dynamic seal auxiliary device for local underwater dry welding of a drainage cover relates to the field of welding, and utilizes a shaftless motor sleeving the periphery of the drainage cover to drive blades to rotate at a high speed through transmission of a magnetic coupling, so that a vortex surrounding the drainage cover is formed in a surrounding water area to prevent seawater from entering the cover. Due to the fact that the drainage cover does not need to be tightly attached to the welding surface for sealing, sealing can be conducted when the drainage cover moves and the welding surface is complex, and the stability of a dry cavity in the drainage cover is effectively guaranteed. Meanwhile, the shaftless motor is adopted for driving on the periphery of the drainage cover, so that the internal space of the drainage cover is not occupied at all, the internal space of the drainage cover can be distributed to other welding parts more freely, and more complex and high-quality welding work can be carried out conveniently. In the device, the fan blades and the motor are connected through the magnetic coupler, vibration of the welding drainage cover in the working process is greatly reduced, and the welding quality is effectively improved.

Description

Technical Field

[0001] The invention belongs to the field of welding, and in particular relates to a dynamic sealing auxiliary device for a local underwater dry welding drainage cover. Background Art

[0002] In recent years, as the international situation surrounding my country has become increasingly severe, increasing the intensity of ship mission deployment and reducing their maintenance cycles have become of great strategic significance in order to safeguard my country's maritime rights and interests. Therefore, there is an urgent need to explore a technology that can perform in-situ repairs in the open ocean to restore the combat capability of ships in the shortest possible time and ensure their ability to continue to perform their missions.

[0003] Underwater localized dry welding technology uses a specialized welding drain hood to pressurize and drain the surface being repaired, creating a localized dry cavity. This creates a similar effect to dry welding, significantly improving the efficiency and quality of underwater in-situ repairs. However, current welding drain hoods typically seal the dry cavity with a high-temperature-resistant rubber skirt. As the hood moves along the weld during repair, seawater can seep into the localized dry cavity through gaps in the hood's bottom, severely impacting weld quality and stability.

[0004] Currently, the field of underwater local dry welding primarily uses internal high-pressure inert gas for drainage and a high-temperature-resistant rubber skirt to seal the dry cavity within the hood. This sealing method works well when the welding hood is stationary. However, if the hood is lifted and moved, instead of being in close contact with the weld surface, seawater can penetrate the hood's dry cavity through the gaps at the bottom. Furthermore, due to factors such as seawater impact, the weld surface in the ocean often exhibits pits, bumps, and a certain curvature. The hood cannot remove water trapped in the pits on the weld surface through traditional physical sealing methods like the skirt, which seriously affects the stability of the hood's dry cavity. Furthermore, in some solutions that use a motor to drive the blades, the motor's drive shaft must be placed in the center of the hood, seriously compromising the installation of internal equipment. Furthermore, the motor's connection to the fan blades via the drive shaft causes the vibrations generated by the blades during operation to be directly transmitted to the motor and, in turn, to the hood connected to the motor, causing severe vibration in the hood and affecting the quality of the welding work.

[0005] In response to this problem, there is an urgent need to find a way to enable the drainage hood to dynamically seal the local dry cavity inside the hood during the movement of the welding operation. Based on this, the patent with publication number CN208033901U discloses a local dry gas shielded welding drainage hood device for realizing dual rotation of gas and water. The device uses a micro motor to drive high-speed rotating blades in combination with high-pressure inert gas to achieve effective sealing inside the hood, significantly improving the welding quality. However, this solution also has certain defects. Specifically, on the one hand, since the motor is directly installed in the hood for driving, the sealing performance of the device is poor and it is not suitable for immersion in deep water. On the other hand, the installation of the motor shaft in the center of the hood seriously affects the layout of the welding device in the hood, making it difficult to perform high-quality welding work with complex device requirements. Summary of the Invention

[0006] The present invention proposes a dynamic sealing auxiliary device for a local underwater dry welding drain cover, which uses a large-aperture shaftless motor as a drive and is connected to the blades through a magnetic coupling. After high-pressure inert gas is introduced into the drain cover, the drive device is started to rotate the blades at high speed to form a circle of high-speed rotating vortex at the lower edge of the drain cover to separate the seawater outside the drain cover from the dry cavity inside the drain cover, so that the drain cover can effectively ensure the stability of the local dry cavity during the mobile operation. The present invention is intended to solve the difficult problem of the failure of dynamic sealing in complex working conditions such as when the local dry underwater welding drain cover is moving and there are pits or protrusions on the welding surface, that is, the inability to effectively ensure the stability of the dry cavity inside the cover.

[0007] The present invention provides a local underwater dry welding drainage cover dynamic sealing auxiliary device, which includes a motor, a motor housing, a magnetic coupling and a fan blade;

[0008] The auxiliary device is a hollow cylindrical structure and is installed at the bottom of the drain cover body. The motor housing is composed of a motor upper housing, a motor main body shell and a motor lower housing from top to bottom; the motor lower housing is connected to the magnetic coupling housing, and the bottom of the drain cover body is concave inward to form a motor inner ring sealing shell. The motor inner ring sealing shell is arranged at the connection between the drain cover body and the inside of the motor housing. The motor upper housing and the motor lower housing are opened at the center. The upper end surface of the high-temperature resistant rubber skirt is connected to the end surface of the central opening of the motor lower housing, and the lower end surface is located below the magnetic coupling housing. The welding gun is placed in the drain cover body;

[0009] The motor is a shaftless motor, comprising an upper tapered roller bearing, a motor rotor, a motor stator, a copper coil and a lower tapered roller bearing; the magnetic coupling is composed of an upper yoke and a copper disk of the magnetic coupling and a lower yoke and a permanent magnet;

[0010] The motor stator is fixed to the motor main body shell by interference fit, the motor rotor is connected by connecting the rotor bottom with the upper yoke and copper disk of the magnetic coupling, the lower yoke and permanent magnet of the magnetic coupling are connected to the magnetic coupling shell, and the fan blades are connected to the lower yoke and permanent magnet of the magnetic coupling.

[0011] Furthermore, the motor upper housing is connected to the motor main body shell by a first fastening bolt, and the motor main body shell is connected to the motor lower housing by a second fastening bolt; a sealing gasket is provided between the motor main body shell and the motor lower housing.

[0012] Furthermore, the motor lower housing and the magnetic coupling housing are connected by a third fastening bolt, and a sealing gasket is provided between the motor lower housing and the magnetic coupling housing.

[0013] Furthermore, the lower end surface of the high temperature resistant rubber skirt in the vertical direction is lower than the horizontal plane of the fan blades.

[0014] Furthermore, the motor inner ring sealing shell is connected to the bottom of the drainage cover body through interference fit.

[0015] Furthermore, the upper yoke and the copper disk of the magnetic coupling are sealed together with the motor in the motor housing.

[0016] Furthermore, the lower yoke of the magnetic coupling and the permanent magnet are placed inside the magnetic coupling housing through positioning balls, which are embedded in the magnetic coupling housing and match the concave grooves of the lower yoke of the magnetic coupling and the permanent magnet.

[0017] Furthermore, the lower yoke of the magnetic coupling and the bottom of the permanent magnet are provided with sockets, and the fan blades are inserted into the sockets and have an interference fit with the sockets.

[0018] Technical principle of the present invention:

[0019] The present invention proposes a dynamic sealing auxiliary device for a local underwater dry welding drain hood, which utilizes a shaftless motor sleeved on the periphery of the drain hood, and drives the blades to rotate at high speed through a magnetic coupling, so that the surrounding water forms a vortex around the drain hood to prevent seawater from entering the hood. Since this device does not require the drain hood to be tightly attached to the welding surface for sealing, it can be sealed when the drain hood moves and the welding surface is more complex, effectively ensuring the stability of the dry cavity inside the drain hood. At the same time, since a shaftless motor is used to drive the drain hood at the periphery, the space inside the drain hood will not be occupied at all, so that the space inside the drain hood can be more freely allocated to other welding components, so as to facilitate more complex and high-quality welding work. In addition, in this device, the fan blades and the motor are connected by a magnetic coupling, which greatly reduces the vibration of the welding drain hood during operation and effectively improves the welding quality.

[0020] (1) The present invention uses a dedicated shaftless permanent magnet synchronous motor as a drive device to directly drive the outer periphery of the lower part of the drain cover. On the one hand, the internal space of the drain cover can be fully utilized, and there is enough space to install various welding equipment, which greatly ensures the practicality of the welded drain cover. On the other hand, compared with motors with shaft drive, the shaftless motor eliminates the complex transmission structure and adopts rotor direct drive technology, effectively improving the transmission efficiency and greatly reducing the overall mass of the drainage device.

[0021] (2) The present invention uses a magnetic coupling as a transmission device. On the one hand, the upper yoke of the magnetic coupling is directly connected to the copper disk and the motor rotor and is encapsulated in a completely sealed pressure-resistant shell. The lower yoke of the magnetic coupling and the permanent magnet are connected to the fan blades in the external magnetic coupling shell for driving. This ensures good sealing of the shaftless permanent magnet synchronous motor without affecting the transmission performance. On the other hand, since the fan blades that directly interact with seawater do not use a direct mechanical connection with the motor, but a magnetic connection, this non-mechanical connection design can effectively filter out the vibration generated by the fan blades when they are working, significantly reducing the vibration of the motor and the welding drainage cover connected to the motor, thereby ensuring the quality of the welding work.

[0022] (3) The present invention uses the high-speed rotation of the fan blades in the seawater to generate a vortex to isolate the seawater from the dry cavity inside the drainage cover. This allows the welding drainage cover to always be at the center of the vortex during movement, and the vortex can carry away seawater from complex surfaces such as pits along the way. This effectively solves the problem of the welding drainage cover being unable to effectively maintain the stability of the local dry cavity inside the cover when the working surface presents convexities, concavities, or a certain curvature.

[0023] The present invention has the following beneficial effects:

[0024] (1) The present invention uses a fan blade that rotates at high speed in seawater to generate a vortex to isolate the seawater from the dry cavity in the drain cover, effectively removing seawater from complex weld surfaces such as pits. This allows the drain cover to effectively maintain the stability of the dry cavity in the case of convex, concave, or curvature conditions.

[0025] (2) The present invention adopts a special shaftless permanent magnet synchronous motor as a driving device to directly drive the periphery of the lower part of the drain cover, effectively ensuring the use space inside the drain cover, so that there is enough space inside the drain cover to install welding equipment.

[0026] (3) The present invention adopts a magnetic coupling as a transmission device, which avoids the mechanical connection between the fan blades and the motor. The magnetic connection can effectively filter out the vibration generated by the fan blades when they are working, so that the vibration of the motor and the welding drainage cover connected to the motor is significantly reduced, thereby ensuring the quality of the welding work. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the structure of the device of the present invention;

[0028] Figure 2 for Figure 1 cross-sectional view;

[0029] Figure 3 for Figure 1 Top view, the arrow direction is the direction of rotation of the fan blade;

[0030] Figure 4 for Figure 1 Side view;

[0031] Figure 5 Schematic diagram of the connection between the magnetic coupling housing, the lower yoke of the magnetic coupling and the permanent magnet;

[0032] In the figure, the water cover body 101, the motor inner ring sealing shell 102, the motor upper shell 201, the first fastening bolt 202, the motor main shell 203, the sealing gasket 204, the motor lower shell 205, the second fastening bolt 206, the upper tapered roller bearing 207, the motor rotor 208, the motor stator 209, the copper coil 210, the lower tapered roller bearing 211, the third fastening bolt 301, the sealing gasket 302, the magnetic coupling shell 303, the magnetic coupling upper yoke and copper disk 304, the magnetic coupling lower yoke and permanent magnet 305, and the fan blade 401. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention more clearly understood, the spirit of the contents disclosed in the present invention will be described in detail below. After understanding the embodiments of the contents of the present invention, any technician in the relevant technical field can change and modify the contents of the present invention based on the techniques taught by the contents of the present invention without departing from the spirit and scope of the contents of the present invention.

[0034] The exemplary embodiments of the present invention and the description thereof are used to explain the present invention but are not intended to limit the present invention.

[0035] Example

[0036] A local underwater dry welding drainage cover dynamic sealing auxiliary device, the auxiliary device is a hollow cylinder installed on the periphery of the lower part of the drainage cover body 101, the external body of the auxiliary device mainly includes the motor upper shell 201, the first fastening bolt 202, the motor main body shell 203, the sealing gasket 204, the motor lower shell 205, the second fastening bolt 206, the third fastening bolt 301, the sealing gasket 302, the magnetic coupling shell 303, and the fan blade 401.

[0037] The auxiliary device is equipped with a motor inner ring sealing shell 102, an upper tapered roller bearing 207, a motor rotor 208, a motor stator 209, a copper coil 210, a lower tapered roller bearing 211, an upper yoke and a copper disk 304 of a magnetic coupling, a lower yoke and a permanent magnet 305. The device still retains a high-temperature resistant rubber skirt 402, which can ensure the sealing performance during static drainage on the one hand, and on the other hand ensure that the fan blades 401 maintain a certain distance from the welded surface to prevent the fan blade movement from interfering with the welding surface.

[0038] To ensure the motor's sealing performance at a certain water depth, a fully sealed, pressure-resistant housing is employed. The motor's upper housing 201, main motor housing 203, lower motor housing 205, and inner seal housing 102 are connected by first and second fastening bolts 202 and 206 (some fastening bolts are not shown). Sealing washers 204 and 302 (some sealing washers are not shown) are installed between the connecting surfaces to provide a waterproof seal. The interconnected housings form a sealed, waterproof cavity, which houses an upper tapered roller bearing 207, motor rotor 208, motor stator 209, copper coil 210, lower tapered roller bearing 211, and the upper yoke and copper disk 304 of the magnetic coupling. The inner seal housing 102 is connected to the lower portion of the drain cover body 101 via an interference fit.

[0039] To minimize space consumption within the drain housing, this design utilizes a uniquely designed shaftless permanent magnet synchronous motor. The motor stator 209 is secured to the motor housing 203 via an interference fit. The motor rotor 208 is directly driven by extending the lower rotor section and connecting it to the yoke and copper plate 304 of the magnetic coupling, eliminating the need for a shaft-free rotor transmission. Furthermore, because the device operates in flowing seawater, it utilizes natural water cooling, eliminating the need for a separate cooling system.

[0040] Because the motor is entirely sealed within the pressure-resistant housing, this design uses a magnetic coupling to connect the motor rotor and blades to achieve motor transmission and load drive. The magnetic coupling consists of an upper yoke and copper disk 304, and a lower yoke and permanent magnet 305. As mentioned above, the upper yoke and copper disk 304 are sealed within the pressure-resistant housing along with the motor, while the lower yoke and permanent magnet 305 are positioned within the coupling housing 303 via a positioning ball (not shown). The lower yoke has a socket at the bottom to allow the fan blades to be inserted and fixed to the yoke.

[0041] When the device of this embodiment is in use, the working process is as follows:

[0042] S1: The device is delivered to the welding surface that needs to be repaired in situ, so that the high temperature resistant rubber skirt 402 is closely fitted to the welding surface.

[0043] S2: High-pressure gas is introduced through the vent holes of the welded drain cover to create a local dry cavity environment inside the drain cover.

[0044] S3: Start the drainage hood dynamic sealing auxiliary device to stir the surrounding seawater to form a vortex until the vortex exists stably.

[0045] S4: Lift the welding drain cover so that there is a small distance between the high temperature resistant rubber skirt 402 and the welding surface, so that the drain cover can be moved for welding operation.

[0046] S5: After the welding operation is completed, the high temperature resistant rubber skirt 402 is again closely fitted to the welding surface.

[0047] S6: Close the drain cover dynamic seal auxiliary device.

[0048] S7: Stop supplying high-pressure gas, complete the welding operation and recycle the working device.

[0049] This embodiment uses the high-speed rotation of the fan blades to, on the one hand, swirl the surrounding seawater into a natural water curtain wall to prevent external seawater from infiltrating the dry cavity within the drainage hood. On the other hand, it also guides the high-pressure inert airflow within the hood, allowing it to flow out of the hood in an orderly manner, reducing the vibration of the drainage hood itself caused by the turbulent airflow within the hood, and further improving the accuracy of underwater welding operations. The fan blades of this embodiment are connected to the yoke of the lower part of the magnetic coupling through fixed holes, which can facilitate the replacement of the fan blade style according to different work requirements and different working conditions, allowing the equipment to operate effectively under conditions of multiple scenarios and multiple working conditions.

Claims

1. A dynamic sealing auxiliary device for local underwater dry welding drainage cover, characterized in that It includes a motor, a motor housing, a magnetic coupling and a fan blade (401); The auxiliary device is a hollow cylindrical structure, which is installed at the bottom of the drainage cover body (101). The motor housing is composed of a motor upper housing (201), a motor main body shell (203) and a motor lower housing (205) from top to bottom; the motor lower housing (205) is connected to the magnetic coupling housing (303), and the bottom of the drainage cover body (101) is concave inward to form a motor inner ring sealing shell (102). The motor inner ring sealing shell (102) is arranged at the connection between the drainage cover body (101) and the inside of the motor housing. The motor upper housing (201) and the motor lower housing (205) are opened at the center. The upper end face of the high-temperature resistant rubber skirt (402) is connected to the end face of the central opening of the motor lower housing (205), and the lower end face is located below the magnetic coupling housing (303). The welding gun is placed in the drainage cover body (101); The motor is a shaftless motor, comprising an upper tapered roller bearing (207), a motor rotor (208), a motor stator (209), a copper coil (210) and a lower tapered roller bearing (211); the magnetic coupling is composed of an upper yoke and a copper disk (304) of the magnetic coupling and a lower yoke and a permanent magnet (305) of the magnetic coupling; The motor stator (209) is fixed to the motor main body housing (203) by interference fit, the motor rotor (208) is connected by connecting the rotor bottom with the upper yoke of the magnetic coupling and the copper disk (304), the lower yoke of the magnetic coupling and the permanent magnet (305) are connected to the magnetic coupling housing (303), and the fan blade (401) is connected to the lower yoke of the magnetic coupling and the permanent magnet (305).

2. The dynamic sealing auxiliary device for a local underwater dry welding drainage cover according to claim 1 is characterized in that The motor upper housing (201) is connected to the motor main housing (203) via a first fastening bolt (202), and the motor main housing (203) is connected to the motor lower housing (205) via a second fastening bolt (206); a sealing gasket (204) is provided between the motor main housing (203) and the motor lower housing (205).

3. The dynamic sealing auxiliary device for a local underwater dry welding drainage cover according to claim 1 is characterized in that The motor lower housing (205) and the magnetic coupling housing (303) are connected via a third fastening bolt (301), and a sealing gasket (302) is provided between the motor lower housing (205) and the magnetic coupling housing (303).

4. The dynamic sealing auxiliary device for a local underwater dry welding drainage cover according to claim 1 is characterized in that In the vertical direction, the lower end surface of the high-temperature resistant rubber skirt (402) is lower than the horizontal plane of the fan blade (401).

5. The dynamic seal auxiliary device for local underwater dry welding drainage cover according to claim 1 is characterized in that The motor inner ring sealing shell (102) is connected to the bottom of the drainage cover body (101) through interference fit.

6. The dynamic seal auxiliary device for a local underwater dry welding drainage cover according to claim 1 is characterized in that The upper yoke iron and the copper disk (304) of the magnetic coupling are sealed together with the motor in the motor housing.

7. The dynamic seal auxiliary device for a local underwater dry welding drainage cover according to claim 1 is characterized in that The lower yoke of the magnetic coupling and the permanent magnet (305) are placed inside the magnetic coupling housing (303) through a positioning ball (306), and the positioning ball (306) is embedded in the magnetic coupling housing (303). The positioning ball (306) matches the concave grooves of the lower yoke of the magnetic coupling and the permanent magnet (305).

8. The dynamic seal auxiliary device for local underwater dry welding drainage cover according to claim 1 is characterized in that The bottom of the lower yoke of the magnetic coupling and the permanent magnet (305) is provided with a socket, and the fan blade (401) is inserted into the socket and has an interference fit with the socket.

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