Ship underwater welding seam quality detection device

Abstract

The invention discloses a ship underwater welding seam quality detection device, and relates to the technical field of ship welding seam detection, the ship underwater welding seam quality detection device comprises a detector, a gooseneck pipe, a pipe body limiting assembly, an end part frame, a clamping and fixing assembly and a detection unit, the top end of the detector is provided with a receiving end, and the detection unit is fixed below the end part frame. Comprising a camera body, an illumination lamp and a protective shell. The camera body is fixed below the gooseneck, and a transmitting end is arranged at the top of the camera body; the illumination lamp is fixed on the camera body; the protective shell is of a hollow capsule structure and is fixed on the outer side of the camera body, the protective shell is made of a transparent silica gel material and is communicated with an external air pump through a pipeline, and the camera body is protected through inflation expansion and contraction; the technical effects that the detection range is expanded, the equipment damage risk is reduced, the detection efficiency is improved, and the detection accuracy is improved can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ship weld detection, and in particular to a ship underwater weld quality detection device. Background Art

[0002] Ship weld quality inspection is crucial for ensuring ship structural integrity and navigation safety. As the core connection between hull steel plates, weld quality directly impacts the strength and sealing of the hull. Traditional manual inspections are inefficient, risky, and prone to missed and false detections, making them inadequate to meet the stringent safety and economic demands of the modern shipping industry.

[0003] Regarding the inspection of ship welds, the Chinese invention patent with patent number CN117288771B discloses a quality inspection device based on ship welds, which effectively solves the current problem of difficulty in protecting the camera when extending it into a narrow position in the hull. The device includes a detector, a gooseneck tube is installed at the top of the detector, and the gooseneck tube is arranged in an N shape. An end frame is installed at one end of the gooseneck tube, and a detection control component is installed on the end frame. A tube body limiting component is installed on the side of the detector close to the end frame, a clamping and fixing component is installed at the bottom end of the detector, and a display is provided on the front of the detector. The detection control component includes a transmitting end installed at the top end of the end frame; the invention arranges the camera body inside the fixed cover. When the camera body needs to enter the gap position to shoot the weld, the fixed cover and the two movable covers form a protective cover to protect the camera body inside, thereby protecting the camera body when passing through the gap position.

[0004] Although the above solution improves the operational efficiency to a certain extent when inspecting ship welds, in actual use, since most ships are docked at the water's edge, the ship welds being inspected may be located underwater or in high-humidity areas (such as the bottom of the cabin) during the inspection process. Since there are no existing waterproof measures, it is impossible to inspect welds in underwater environments, nor can it meet the requirements of underwater or humid environment inspections, which may cause damage to the camera body and circuit, affecting the efficiency and accuracy of the inspection. Summary of the Invention

[0005] This application solves the technical problems in the prior art of limited detection range, high risk of equipment damage, reduced detection efficiency and reduced detection accuracy by providing a ship underwater weld quality inspection device, and achieves the technical effects of expanding the detection range, reducing the risk of equipment damage, improving detection efficiency and improving detection accuracy.

[0006] The present application provides a device for detecting underwater weld quality of a ship, comprising a detector, a gooseneck tube, a tube limit assembly, an end frame, a clamping and fixing assembly, and a detection unit. The top of the detector is provided with a receiving end, and the detection unit is fixed below the end frame and comprises a camera body, a light, and a protective shell.

[0007] The camera body is fixed under the gooseneck tube and a transmitting end is provided on the top of the camera body; the illumination lamp is fixed on the camera body;

[0008] The protective shell is a hollow sac structure, fixed to the outside of the camera body. The protective shell is made of transparent silicone material and is connected to an external air pump through a pipe. It protects the camera body through inflation and contraction.

[0009] Furthermore, the protective shell is divided into two cover shells, which are hemispherical capsule structures and are respectively located on the left and right sides of the camera body to balance the stability of the camera body during underwater detection.

[0010] Furthermore, the cover shell includes an inner layer capsule and an outer layer capsule; the inner layer capsule is coated on the outside of the camera body; the outer layer capsule is fixed on the outside of the inner layer capsule and has a conical sector structure.

[0011] Furthermore, a plurality of reinforcing ribs are evenly arranged along the circumference of the inner side surface of the outer sac to enhance the overall structural strength of the protective shell; the reinforcing ribs are strip-shaped sac structures and are connected to the interior of the inner sac, and are used to drive the outer sac to expand outward and form a hollow frustum structure through the expansion of the reinforcing ribs when the inner sac is inflated.

[0012] Furthermore, the outer bladder covers the weld and the external water body after being unfolded, and after the inner bladder is inflated, a negative pressure closed space is formed between the outer bladder, the weld and the water body to ensure the stability of the internal water quality during detection.

[0013] Furthermore, the inner layer bag is provided with three layers, which are divided into expansion membrane one, expansion membrane two, and expansion membrane three from the inside to the outside. An expansion cavity is formed between the expansion membrane one and the expansion membrane two, and between the expansion membrane two and the expansion membrane three. Multiple expansion cavities are expanded in sequence to form a multi-stage expansion structure, and each expansion cavity is expanded step by step through independent air path control.

[0014] Furthermore, the thicknesses of the first expansion membrane, the second expansion membrane, and the third expansion membrane increase sequentially from the inside to the outside.

[0015] Furthermore, a one-way valve 1 and a one-way valve 2 are detachably fixed to the outside of the outer bladder, and are used to replace the water wrapped inside the outer bladder when the inner bladder is inflated.

[0016] Furthermore, a micro filter is provided inside the one-way valve 1 to control the inflow of clean water; the one-way valve 2 is used to control the outflow of internal water, and cooperates with the one-way valve 1 to complete water replacement.

[0017] Furthermore, a plurality of closed openings are evenly opened on the outer side surface of the outer layer bag along its circumference, and the closed openings correspond to the reinforcing ribs one by one, and the closed openings are communicated with the interior of the reinforcing ribs; a plurality of metal balls are arranged inside the reinforcing ribs, and metal balls of different weights are loaded into the corresponding reinforcing ribs through the closed openings to adjust the buoyancy state of the protective shell in water.

[0018] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0019] The protective shell with a hollow sac structure forms a tight sealing structure after inflation, which can effectively isolate water and moisture, and protect the camera body and internal circuits from the influence of underwater or high humidity environments; when the protective shell is inflated and impacted by external force, it can absorb and disperse the impact force through its own deformation, providing effective buffering protection for the camera body; it effectively solves the technical problems in the existing technology of limited detection range, high risk of equipment damage, reduced detection efficiency and reduced detection accuracy, and achieves the technical effects of expanding the detection range, reducing the risk of equipment damage, improving detection efficiency and improving detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is an overall structural diagram of a device for detecting underwater weld quality of a ship according to the present invention.

[0021] Figure 2 This is a side perspective structural diagram of a protective shell of a device for detecting underwater weld quality of a ship according to the present invention.

[0022] Figure 3 This is a diagram of the overall structure of the outer bag of a ship underwater weld quality inspection device of the present invention when it is unfolded.

[0023] Figure 4 The present invention is a three-dimensional structural diagram of a cover of a device for detecting underwater weld quality of a ship.

[0024] Figure 5 This is a three-dimensional structural diagram of the inner and outer bladders of a device for detecting underwater weld quality of a ship according to the present invention.

[0025] Figure 6 The present invention is a partial three-dimensional cross-sectional view of an outer bag of a device for detecting underwater weld quality of a ship.

[0026] Figure 7 The present invention is a partial three-dimensional cross-sectional view of the inner bladder and the outer bladder of a device for detecting the quality of underwater welds on ships.

[0027] Figure 8 The present invention is a schematic diagram of the state of the reinforcement rib of a ship underwater weld quality inspection device when the metal ball is installed.

[0028] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0029] 100. Detector; 101. Transmitter; 102. Receiver; 110. Gooseneck; 120. Tube limit assembly; 130. End frame; 140. Clamping and fixing assembly; 150. Camera body; 160. Illuminator; 170. One-way valve 1; 180. One-way valve 2; 200. Protective shell; 210. Cover; 220. Inner bladder; 221. Expansion membrane 1; 222. Expansion membrane 2; 223. Expansion membrane 3; 230. Outer bladder; 231. Reinforcement rib; 232. Metal ball; 240. Closing mouth. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0031] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the described features. In the description of this application, "plurality" means two or more, unless otherwise specifically specified.

[0032] In the description of this application, the term "for example" is used to mean "used as an example, illustration or explanation". Any embodiment described as "for example" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any person skilled in the art to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art will recognize that the present invention can be implemented without using these specific details. In other examples, well-known structures and processes will not be elaborated in detail to avoid obscuring the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in this application.

[0033] See also Figure 1, which is a schematic diagram of the overall structure of a ship underwater weld quality inspection device of the present invention; the ship weld quality inspection device of the present application forms a tight sealing structure through a protective shell with a hollow sac structure after inflation, which can effectively isolate water and moisture, and protect the camera body and internal circuit from the influence of underwater or high humidity environment; when the protective shell is inflated and expanded by air, it can absorb and disperse the impact force through its own deformation when impacted by external force, providing effective buffering protection for the camera body; it achieves the technical effects of expanding the detection range, reducing the risk of equipment damage, improving detection efficiency and improving detection accuracy.

[0034] Example 1:

[0035] like Figure 1 and Figure 6 As shown, the present application discloses a device for underwater weld quality inspection of ships, comprising a detector 100, a gooseneck tube 110, a tube body limiting assembly 120, an end frame 130, a clamping and fixing assembly 140, and a detection unit. The detector 100 is provided with a receiving end 102 at the top, and the detection unit is fixed below the end frame 130 and comprises a camera body 150, a light 160, and a protective shell 200.

[0036] The camera body 150 is fixed below the gooseneck tube 110 and a transmitting end 101 is provided on the top of the camera body 150; the illumination lamp 160 is fixed on the camera body 150;

[0037] The protective shell 200 is a hollow sac structure, fixed to the outside of the camera body 150. The protective shell 200 is made of transparent silicone material and is connected to an external air pump through a pipe. It protects the camera body 150 by inflation and contraction.

[0038] The tube body limiting assembly 120 is used to limit and fix the gooseneck tube 110, including a fixing plate, a limiting groove, a limiting plate, an end plate and a fourth spring. The gooseneck tube 110 is mainly limited and fixed by the limiting plate and the limiting groove to prevent the gooseneck tube 110 from shaking during the detection process and affecting the detection; the clamping and fixing assembly 140 is used to control the coordinated operation of various components of the detection platform, including a bottom swivel, a clamping ring, a bottom plate, an airbag and an air nozzle, and is mainly clamped and fixed by inflating the airbag; the camera body 150 has a built-in battery and is connected to the transmitting end 101 through a circuit for transmitting detection signals; all of these are existing technologies and will not be described here.

[0039] During actual operation of the embodiment of the present application, the steps are as follows: First, when in use, the device is fixed to the pipe near the weld by clamping the fixing assembly 140. At this time, the protective shell 200 is in a contracted state, and the camera body 150 is tightly wrapped in the inner layer bag 220; then, the position of the camera body 150 is adjusted according to the detection position through the gooseneck tube 110, and the gooseneck tube 110 is limited and fixed by the tube body limiting assembly 120, and the position of the camera body 150 is positioned; finally, the protective shell 200 is inflated by a micro external air pump. The protective shell 200 begins to expand to protect and waterproof the camera body 150. The camera body 150 begins to capture the weld image. The light 160 provides lighting. The detection signal is transmitted through the transmitting end 101. The receiving end 102 receives and processes the signal and displays the image on the display of the detector 100. After the detection is completed, the gas in the inner layer bag 220 is discharged by the micro air pump. The protective shell 200 gradually shrinks to its initial state, the camera body 150 and the gooseneck tube 110 are restored to their original state, and the entire device is removed by clamping the fixing component 140.

[0040] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages:

[0041] The present application provides a protective shell 200 with a hollow sac structure, which can form a tight sealing structure after inflation, effectively isolating water and moisture, protecting the camera body 150 and internal circuits from the influence of underwater or high humidity environments, effectively preventing the intrusion of water and dust, ensuring the durability of the sealing effect, further enhancing the waterproof performance, helping to extend the service life of the equipment and reduce maintenance costs; the expansion and contraction of the protective shell 200 can be easily achieved by controlling the external air pump, thereby improving the flexibility of the detection device, enabling it to adapt to the detection needs of welds of different shapes and sizes, and improving the detection efficiency and accuracy.

[0042] At the same time, the silicone material has good elasticity. When the protective shell 200 is impacted by external force, it can absorb and disperse the impact force through its own deformation, providing effective buffering protection for the camera body 150; it effectively solves the technical problems in the existing technology such as limited detection range, high risk of equipment damage, reduced detection efficiency and reduced detection accuracy, and achieves the technical effects of expanding the detection range, reducing the risk of equipment damage, improving detection efficiency and improving detection accuracy.

[0043] Example 2:

[0044] When inspecting welds submerged in water (such as ship bottom welds), the water is always in a flowing state, which affects the inspection results. The water flow disturbs the suspended matter and light in the water, causing the image captured by the camera to be blurred or distorted, affecting the inspector's accurate judgment of the weld quality. In order to improve the inspection accuracy, this application proposes the following technical solutions to address the above technical problems, specifically:

[0045] like Figures 1 to 4 As shown, the protective shell 200 is divided into two cover shells 210. The two cover shells 210 are hemispherical capsule structures and are respectively located on the left and right sides of the camera body 150 to balance the stability of the camera body 150 during underwater detection.

[0046] The cover shell 210 includes an inner layer capsule 220 and an outer layer capsule 230 ; the inner layer capsule 220 covers the outside of the camera body 150 ; the outer layer capsule 230 is fixed to the outside of the inner layer capsule 220 and has a conical sector structure.

[0047] The inner side surface of the outer sac 230 is evenly provided with a plurality of reinforcing ribs 231 along its circumference, which are used to enhance the overall structural strength of the protective shell 200; the reinforcing ribs 231 are strip-shaped sac structures and are communicated with the interior of the inner sac 220. When the inner sac 220 is inflated, the outer sac 230 is driven to expand outward through the expansion of the reinforcing ribs 231 and form a hollow frustum structure.

[0048] The outer bladder 230 covers the weld and the external water body after being unfolded, and after the inner bladder 220 is inflated, a negative pressure closed space is formed between the outer bladder 230, the weld and the water body to ensure the stability of the internal water quality during detection.

[0049] The present application sets a reinforcing rib 231 so that when the inner bag 220 is inflated, the outer bag 230 unfolds and forms a truncated cone structure under the guidance of the reinforcing rib 231, covering the weld and the water body outside it to form a negative pressure closed space, which to a certain extent suppresses the disturbance of the water flow, reduces the direct impact and disturbance of water molecules on the weld surface, helps to maintain the relative stability of the weld surface, and improves the clarity and accuracy of image acquisition; at the same time, this negative pressure effect can effectively reduce the penetration of water molecules, enhance the overall sealing performance of the protective shell 200, and ensure the dryness and safety of the internal camera body 150 and electronic equipment.

[0050] The conical fan structure of the outer bladder 230 helps to form a dynamic balance in the water flow, reduce the structural shaking caused by changes in the direction of the water flow, and further improve the stability of the detection; the provision of multiple reinforcing ribs 231 not only enhances the overall structural strength of the protective shell 200, but also can disperse stress when inflated, thereby improving the compressive resistance of the protective shell 200 and enabling it to withstand the complex stress changes in the underwater environment.

[0051] Example 3:

[0052] Considering that the water quality in the area where the weld is being tested may be relatively turbid, and the water covering the weld contains impurities that may interfere with the detection process, in order to improve the detection efficiency and further improve the detection accuracy, this application proposes the following technical solutions to the above technical problems, specifically:

[0053] like Figures 5 to 7 As shown, the inner bladder 220 is configured with three layers: from the inside out, expansion membrane 1 221, expansion membrane 2 222, and expansion membrane 3 223. Expansion chambers are formed between expansion membrane 1 221 and expansion membrane 2 222, and between expansion membrane 2 222 and expansion membrane 3 223. Multiple expansion chambers expand sequentially to form a multi-stage expansion structure, with each expansion chamber expanding step by step via an independent air circuit. When the pressure in the air circuit reaches a certain value, the secondary air circuit opens for step-by-step expansion.

[0054] The thicknesses of the first expansion film 221 , the second expansion film 222 , and the third expansion film 223 increase sequentially from the inside to the outside.

[0055] A one-way valve 170 and a one-way valve 2 180 are detachably fixed to the outside of the outer bladder 230 , and are used to replace the water wrapped inside the outer bladder 230 when the inner bladder 220 is inflated.

[0056] The one-way valve 170 is provided with a micro filter inside to control the inflow of clean water; the one-way valve 2 180 is used to control the outflow of internal water, and cooperates with the one-way valve 170 to complete water replacement.

[0057] The present application divides the inner bladder 220 into three layers, and the expansion membrane 1 221, the expansion membrane 2 222 and the expansion membrane 3 223 can expand step by step to form a pressure gradient, and match the opening pressure of the one-way valve 1 170 and the one-way valve 2 180 to ensure that the water replacement process is smooth and efficient; a one-way valve 170 is set to control the entry of clean water, and a micro filter is provided inside to effectively intercept impurities; the one-way valve 2 180 controls the outflow of turbid water to ensure smooth drainage, realizes two-way control of the water body, and accelerates the replacement process; by optimizing the structural design of the inner bladder 220 and the outer bladder 230, and adopting a multi-stage expansion structure and an independent air path design, the device can adapt to the detection needs under different environments and water conditions. Whether it is a deep water environment or complex water conditions, the device can maintain stable performance, thereby improving the durability and service life of the device.

[0058] Example 4:

[0059] Considering that in complex water bodies (such as river estuaries and offshore salinity gradient areas), the inner layer bladder 220 generates buoyancy inside the water body when inflated, making the device prone to tilting due to buoyancy imbalance, in order to make the device more stable in water detection and adapt to different detection environments, the present application proposes the following technical solutions to address the above technical problems, specifically:

[0060] like Figure 7 and Figure 8 As shown, the outer side surface of the outer layer sac 230 is evenly provided with a plurality of closed openings 240 along its circumference, and the closed openings 240 correspond one-to-one to the reinforcing ribs 231, and the closed openings 240 are communicated with the interior of the reinforcing ribs 231; a plurality of metal balls 232 are arranged inside the reinforcing ribs 231, and metal balls 232 of different weights are loaded into the corresponding reinforcing ribs 231 through the closed openings 240 to adjust the buoyancy state of the protective shell 200 in the water.

[0061] Because the inspection environment may be an ocean, lake, or river, each with varying water densities, different underwater environments have different water densities and buoyancy characteristics. The inner bladder 220, when inflated, generates buoyancy within the water, and proper buoyancy is crucial for underwater inspection. If the buoyancy is too great, the device may float on the surface, unable to reach the bottom weld for inspection. If the buoyancy is too low, the device may sink too quickly, making it difficult to control the inspection position and angle.

[0062] The present application artificially controls the counterweight of the metal ball 232 to precisely control the buoyancy state of the detection device in the water, so that it can maintain a stable suspended or sinking state in water bodies of different densities, reduce the risk of capsizing or loss of control due to uneven buoyancy, facilitate the smooth replacement of water quality, improve the stability during detection, enable the detection device to adapt to a wider range of underwater detection scenarios, improve its versatility and applicability, and thus improve detection efficiency and effectiveness.

[0063] It should be noted that, in the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0064] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A ship underwater weld quality detection device, comprising a detector (100), a gooseneck tube (110), a tube body limiting assembly (120), an end frame (130), a clamping and fixing assembly (140) and a detection unit, wherein the top of the detector (100) is provided with a receiving end (102), characterized in that: The detection unit is fixed below the end frame (130) and includes a camera body (150), a lighting lamp (160) and a protective shell (200); The camera body (150) is fixed below the gooseneck tube (110) and a transmitting end (101) is provided on the top of the camera body; the illumination lamp (160) is fixed on the camera body (150); The protective shell (200) is a hollow sac structure, fixed on the outside of the camera body (150), and is made of transparent silicone material. It is connected to an external air pump through a pipe and protects the camera body (150) through inflation and contraction.

2. A ship underwater weld quality inspection device according to claim 1, characterized in that: The protective shell (200) is divided into two cover shells (210). The two cover shells (210) are hemispherical capsule structures and are respectively located on the left and right sides of the camera body (150) to balance the stability of the camera body (150) during underwater detection.

3. A ship underwater weld quality inspection device according to claim 2, characterized in that: The cover shell (210) includes an inner layer capsule (220) and an outer layer capsule (230); the inner layer capsule (220) is wrapped around the outside of the camera body (150); and the outer layer capsule (230) is fixed to the outside of the inner layer capsule (220) and has a conical sector structure.

4. A ship underwater weld quality inspection device according to claim 3, characterized in that: The inner side surface of the outer layer sac (230) is uniformly provided with a plurality of reinforcing ribs (231) along its circumference, for enhancing the overall structural strength of the protective shell (200); the reinforcing ribs (231) are strip-shaped sac structures and communicate with the interior of the inner layer sac (220), and are used for driving the outer layer sac (230) to expand outward and form a hollow truncated cone structure when the inner layer sac (220) is inflated.

5. The underwater weld quality inspection device for ships according to claim 4, characterized in that: The outer bladder (230) covers the weld and the external water body after being unfolded, and after the inner bladder (220) is inflated, a negative pressure closed space is formed between the outer bladder (230), the weld and the water body, so as to ensure the stability of the internal water quality during detection.

6. A ship underwater weld quality inspection device according to claim 5, characterized in that: The inner layer bag (220) is provided with three layers, which are divided into expansion membrane one (221), expansion membrane two (222), and expansion membrane three (223) from the inside to the outside. An expansion cavity is formed between the expansion membrane one (221) and the expansion membrane two (222), and between the expansion membrane two (222) and the expansion membrane three (223). The multiple expansion cavities are expanded in sequence to form a multi-stage expansion structure, and each expansion cavity is expanded step by step through independent air path control.

7. A ship underwater weld quality inspection device according to claim 6, characterized in that: The thicknesses of the expansion membrane 1 (221), the expansion membrane 2 (222), and the expansion membrane 3 (223) increase sequentially from the inside to the outside.

8. The underwater weld quality inspection device for ships according to claim 6, characterized in that: A one-way valve (170) and a one-way valve (180) are detachably fixed to the outside of the outer bladder (230) for displacing the water contained in the outer bladder (230) when the inner bladder (220) is inflated.

9. The underwater weld quality inspection device for ships according to claim 8, characterized in that: The one-way valve (170) is provided with a micro filter inside to control the inflow of clean water; the one-way valve (180) is used to control the outflow of internal water, and cooperates with the one-way valve (170) to complete the water replacement.

10. The underwater weld quality inspection device for ships according to claim 9, characterized in that: The outer side surface of the outer layer bag (230) is uniformly provided with a plurality of closed openings (240) along its circumference, the closed openings (240) corresponding to the reinforcing ribs (231) one by one, and the closed openings (240) are communicated with the interior of the reinforcing ribs (231); a plurality of metal balls (232) are provided inside the reinforcing ribs (231), and metal balls (232) of different weights are loaded into the corresponding reinforcing ribs (231) through the closed openings (240) to adjust the buoyancy state of the protective shell (200) in water.

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