An anti-trawl device for seabed areas and a method for deployment and recovery

Abstract

The present invention discloses an anti-trawl device for a seabed area, which includes a plurality of trawl blocking devices arranged around a protection area. The distance between two adjacent trawl blocking devices is less than the effective width of the trawl to be protected. The trawl blocking device includes a thorn plate, the thorn plate is provided with a base, a cable hole is provided in the center of the base, a cable locking device is provided on the cable hole, and a plurality of thorns are provided around the cable hole. The thorns are arranged radially, with the ends inclined upward and outward. The thorn plate is fixed to the seabed surface by an anchor, and the anchor is connected to the thorn plate by a cable. The connecting plate end of the cable passes through the cable hole and is connected to the cable locking device. The present invention also discloses a method for deploying and recovering the above anti-trawl device for a seabed area. The present invention can adapt to the changes in the seabed topography, has good flexibility, can conduct centralized protection on a relatively large area; can capture and effectively block the trawl; and the construction process of deployment is simple.

Description

Technical Field

[0001] The present invention belongs to the technical field of ocean engineering, and particularly relates to a device for protecting submarine engineering facilities and equipment within a certain area range, preventing accidental damage caused by fishing vessel trawls, and ensuring the stability of the facilities and equipment. Background Art

[0002] In recent years, with the acceleration of global ocean resource development, submarine engineering facilities and equipment have increased significantly. Submarine observation networks, marine environment monitoring equipment, deep-sea biological investigation devices, etc. need to be deployed on the seabed for a long time, posing higher requirements for the protection of the surrounding environment. The development of large-scale fishing has led to an increasingly prominent threat of trawling operations to submarine facilities. Existing anti-trawl technologies have the following deficiencies:

[0003] 1) Traditional structures such as concrete protection piers and steel frame barriers are bulky, with high deployment costs and poor flexibility. They cannot adapt to seabed topography changes and can only provide physical protection for individual equipment, unable to provide centralized protection for a larger area. 2) Electronic chart avoidance systems, electronic fences, etc. mainly rely on the active avoidance of vessels. Small fishing boats usually result in the failure of protection due to equipment shortages or non-standard operations. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides an anti-trawl device for submarine areas and a method for laying and recovering the device. The device can effectively prevent trawls from entering the protected area, ensure the safety and stability of facilities and equipment within the area, provide the last physical defense line for the protected area when soft protection measures such as electronic charts and buoy warnings fail, and the device can adapt to seabed topography changes.

[0005] The present invention is implemented as follows. An anti-trawl device for submarine areas includes a plurality of trawl blocking devices arranged around the protected area. The distance between two adjacent trawl blocking devices is less than the effective width of the trawl to be protected. The trawl blocking device includes a spiny plate. The spiny plate is provided with a base. A cable hole is provided in the center of the base. A cable locking device is provided on the cable hole. A plurality of spines are provided around the cable hole. The spines are arranged radially, with their ends inclined upward and outward. The spiny plate is fixed on the seabed surface by a ship anchor. The ship anchor is connected to the spiny plate through a cable. The connecting plate end of the cable passes through the cable hole and is connected to the cable locking device.

[0006] The cable locking device includes a plurality of flap structures evenly distributed in the circumferential direction. The flap structure includes a support fixed on the upper surface of the base. A flap is provided on the support and is connected to the support through a rotating shaft. A torsion spring is provided between the flap and the base. The torsion spring is sleeved on the rotating shaft.

[0007] The distance between the ship anchor and the ratchet plate is greater than or equal to 20 m.

[0008] The number of cables of each trawl blocking device is greater than or equal to 3, and the included angle between two adjacent cables is less than or equal to 145°.

[0009] The base is made of cast steel parts or precast reinforced concrete parts.

[0010] The base is provided with stiffening ribs.

[0011] The end inclination angle of the pawl is less than or equal to 30°.

[0012] Barbs are provided on the pawl.

[0013] The method for deploying and recovering the above trawl blocking device in the seabed area adopts the following steps:

[0014] 1) According to the size of the protected area, expand the set range of its plane size outline to determine the layout path of the trawl blocking device;

[0015] 2) According to the size of the trawl to be protected, ensure that there is at least one trawl blocking device within the trawl width range, determine the spacing of the trawl blocking devices, and the installation position of each one;

[0016] 3) For each installation position, according to the designed layout orientation of the ship anchor, use the construction tugboat to drive from far to near towards the installation position, so that the ship anchor is anchored into the seabed. After confirming that the set anchoring force is reached, temporarily place the connecting plate end of the cable on the water surface using a buoy;

[0017] 4) Concentrate the connecting plate ends of all the cables at each installation position at the central position, and pass them through the cable holes of the ratchet plate from bottom to top. Then use the hoisting equipment to hoist and place the ratchet plate. After the ratchet plate is in place, adjust the cables to make them straight, and then complete the locking. Cut off the excess cables. Thus, the construction of the trawl blocking device has been completed;

[0018] 5) After the seabed facilities complete their tasks and are recovered, use manual diving or an underwater robot to locate the ship anchor of the trawl blocking device, then use a salvage tool to vertically drag the ship anchor out of the mud surface to release the anchoring, and finally salvage the ratchet plate to complete the demolition of the trawl blocking device and restore the original seabed environment.

[0019] Advantages and technical effects of the present invention: By using multiple spaced and anchored anti-trawl devices for protection, it can adapt to the changes in seabed topography, has good flexibility, and can centrally protect a relatively large area. At the same time, the present invention gives full play to the characteristic of the large horizontal anchoring force of the ship anchor, and combines with the thorn plate to realize the capture and effective blocking of the trawl; in addition, the layout and construction process of the present invention is simple, does not require complex underwater operations, does not require auxiliary operations by artificial or underwater robots, etc., is not limited by the water depth conditions, and the deployment cost is relatively low. After completing the protection task, it can be conveniently and comprehensively recovered, avoiding leaving hidden dangers for later fishery fishing. Description of the Drawings

[0020] Figure 1 is a schematic plan view of the regional anti-trawl device provided by an embodiment of the present invention;

[0021] Figure 2 is a schematic cross-sectional structure view of the trawl blocking device provided by an embodiment of the present invention;

[0022] Figure 3 is a schematic plan view of the structure of the thorn plate provided by an embodiment of the present invention;

[0023] Figure 4 is a schematic view of the cable self-locking device provided by an embodiment of the present invention.

[0024] In the figure, 1 - protection area; 2 - trawl blocking device; 21 - ship anchor; 22 - cable; 23 - thorn plate; 231 - base; 232 - thorn claw; 233 - cable locking device; 234 - cable hole; 2331 - flap; 2332 - rotating shaft; 2333 - support; 2334 - torsion spring. Detailed Embodiments

[0025] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] Please refer to Figures 1 to 4 , a seabed area anti-trawl device, including a plurality of trawl blocking devices 2 arranged around the protection area 1, and the distance between adjacent two of the trawl blocking devices 2 is less than the effective width of the trawl to be protected.

[0027] The trawl blocking device 2 includes a thorn plate 23, the thorn plate 23 is provided with a base 231, a cable hole 234 is provided in the center of the base 231, a cable locking device 233 is provided on the cable hole 234, and a plurality of thorn claws 232 are provided around the cable hole 234, and the thorn claws 232 are arranged radially, with the ends upward and outward inclined.

[0028] The spiny plate 23 is fixed on the seabed surface by the anchor 21. The anchor 21 is connected to the spiny plate 23 through a cable 22. The connecting plate end of the cable 22 passes through the cable hole 234 and is connected to the cable locking device 233.

[0029] The core requirement of the anti-trawl device is to be able to provide a very large horizontal resistance. The present invention gives full play to the characteristic of the large horizontal anchoring force of the anchor, and combines with the spiny plate to realize the capture and effective interception of the trawl. The present invention will cause varying degrees of damage to the fishing net and cannot be used alone. It needs to be used together with soft protection measures such as electronic nautical charts and buoy warnings. It is the last line of defense.

[0030] A more specific preferred solution of this embodiment is as follows:

[0031] The cable locking device 233 includes a plurality of flap structures evenly distributed in the circumferential direction. The flap structure includes a support 2333 fixedly installed on the base 231. A flap 2331 is provided on the support 2333 and is connected to it through a rotating shaft 2332. A torsion spring 2334 is provided between the flap 2331 and the base 231. The torsion spring 2334 is sleeved on the rotating shaft 2332. With this locking structure, lifting the cable can complete the self-locking of the cable, and it has strong anti-unlocking ability and is easy to construct.

[0032] However, the above structure of the cable locking device is not restrictive, and other structures can also be used, such as a combination structure of a lock catch and a sleeve.

[0033] The distance between the anchor 21 and the spiny plate 23 is greater than or equal to 20 m, ensuring that the main stress direction of the cable after the anchor claw catches the net is horizontal.

[0034] The number of cables of each trawl interception device 2 is greater than or equal to 3, and the included angle between two adjacent cables 22 is less than or equal to 145°, so as to ensure the stability of the spiny plate.

[0035] The base 231 should have a certain flexural rigidity. It is recommended to use a cast steel part or a precast reinforced concrete part, and it can be strengthened by providing stiffening ribs.

[0036] The end inclination angle of the anchor claw 232 is less than or equal to 30°, preventing the trawl from falling off. When necessary, barbs can be added to enhance the anti-detachment performance.

[0037] The method for deploying and recovering the above-mentioned anti-trawl device in the seabed area adopts the following steps:

[0038] 1) According to the size of the protection area 1, expand the set range of its plane size outline to determine the deployment path of the trawl interception device.

[0039] 2) According to the size of the trawl to be protected, ensure that there is at least one trawl blocking device 2 within the trawl width range, determine the spacing of the trawl blocking devices 2, and the installation position of each one.

[0040] 3) For each installation position, according to the designed layout orientation of the ship anchor 21, use the construction tugboat to travel towards the installation position from far to near, so that the ship anchor 21 is anchored into the seabed. After confirming that the set anchoring force is reached, temporarily place the connecting plate end of the cable 22 on the water surface using a buoy.

[0041] For the ship anchor to provide sufficient reaction force, it needs to be towed by a tugboat for a certain distance, and the direction of the force in the later stage cannot change too much. Therefore, the construction tugboat should travel towards the installation position of the thorn plate, let the anchor drill into the soil, and provide the anchoring force.

[0042] 4) Concentrate the connecting plate ends of all the cables 22 at each installation position at the central position, and pass them through the cable holes of the thorn plate from bottom to top. Then use the lifting equipment to hoist and place the thorn plate 23. The thorn plate 23 smoothly falls onto the seabed along the cable. After the thorn plate 23 is in place, adjust the cable 22 to make it straight, and then complete the locking. Cut off the excess cable. Thus, the construction of the trawl blocking device 2 has been completed.

[0043] When the device is in use, in case the thorn plate is hooked by the fishing net, it will not be dragged away because the thorn plate is anchored. So at this time, the fishing net is hooked and blocked.

[0044] Adopting the cable locking device provided by this embodiment, which has an upward self-locking function, can effectively prevent the thorn plate from moving upward along the cable.

[0045] The entire construction process of the layout is simple, does not require complex underwater operations, does not require assistance from manual labor or underwater robots, etc., and is not restricted by the water depth conditions.

[0046] 5) After the undersea facilities complete their tasks and are recovered, use manual diving or an underwater robot to locate the ship anchor 21 of the trawl blocking device, and then use the salvage tool to tow the ship anchor 21 vertically out of the mud surface to release the anchoring. Finally, salvage the thorn plate 23 to complete the removal of the trawl blocking device and restore the original seabed environment.

[0047] The anti-trawl device is for protecting the undersea facilities. After they complete their relevant observation or test tasks and are recovered, the anti-trawl device can be removed. If not removed, it will pose a hidden danger to the fishery in this sea area.

[0048] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A device for preventing trawling in the seabed area, characterized in that: It comprises a plurality of trawl arresting devices arranged around the protection area, wherein the distance between two adjacent trawl arresting devices is smaller than the effective width of the trawl to be protected, The trawl arresting device comprises a ratchet plate, wherein the ratchet plate is provided with a base, a cable hole is provided in the center of the base, a cable locking device is provided on the cable hole, and a plurality of ratchets are provided around the cable hole, wherein the ratchets are arranged radially, and the ends thereof are upwardly and outwardly inclined. The thorn plate is fixed to the seabed surface by an anchor, the anchor is connected to the thorn plate by a cable, and the plate-connecting end of the cable passes through the cable hole and is connected to the cable locking device; The cable locking device comprises a plurality of flap structures evenly distributed along the circumferential direction, wherein the flap structure comprises a support fixedly mounted on the base, a flap connected to the support via a rotating shaft is arranged on the support, a torsion spring is arranged between the flap and the base, and the torsion spring is sleeved on the rotating shaft; The number of cables of each trawl arresting device is greater than or equal to 3, and the angle between two adjacent cables is less than or equal to 145°; The base is made of cast steel or prefabricated reinforced concrete; The inclination angle of the end of the pawl is less than or equal to 30°; A barb is provided on the pawl.

2. The anti-trawling device for seabed area according to claim 1, characterized in that: The distance between the anchor and the spine plate is greater than or equal to 20m.

3. The anti-trawling device for seabed area according to claim 1, characterized in that: The base is provided with stiffening ribs.

4. A method for laying and recovering the anti-trawling device in the seabed area according to any one of claims 1 to 3, characterized in that: Use the following steps: 1) According to the size of the protection area, the outer contour of its plane size is set to expand the range and determine the layout path of the trawl arresting device; 2) Ensure that there is at least one trawl arrester within the width of the trawl net according to the size of the trawl net to be protected, determine the spacing of the trawl arresters and the installation point of each one; 3) For each installation point, according to the design and layout of the anchor, use the construction tugboat to move from far to near towards the installation point, so that the anchor is anchored in the seabed. After confirming that the set anchoring force is reached, the connecting plate end of the cable is temporarily placed on the water surface using a buoy; 4) Gather the connecting plate ends of all cables at each installation point at the center and pass them through the cable holes of the thorn plate from bottom to top. Then use the lifting equipment to hoist the thorn plate. After the thorn plate is in place, adjust the cable to make it straight, and then lock it and cut off the excess cable. At this point, the construction of the trawl arresting device has been completed; 5) After the submarine facility has completed its mission and has been recovered, use artificial diving or underwater robots to locate the anchor of the trawl arrester, then use salvage tools to drag the anchor vertically out of the mud surface, release the anchor, and finally salvage the spines to complete the removal of the trawl arrester and restore the original seabed environment.

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