Split suction anchor recovery device and method

Abstract

The present application relates to the technical field of ocean engineering foundation recovery, and particularly relates to a split type suction anchor recovery device and method. The device comprises a counterforce anchor, a support structure, a primary centering device, a secondary centering device and a lifting mechanism. The counterforce anchor is arranged in the seabed to provide a recovery counterforce. The primary centering device is used for rough positioning in a plane, and the secondary centering device is used for fine adjustment of a lifting point. The lifting mechanism is used for connecting and lifting the anchor body to be recovered. Force information of the anchor body is obtained through a positioning rope and a tension sensor, spatial state recognition is realized, and the position of the lifting point is adjusted during the recovery process, so that the lifting point is kept on the extension line of the anchor body axis. The present application can reduce the lifting load and construction cost, and improve the recovery safety and efficiency.

Description

Technical Field

[0001] This invention relates to the field of marine engineering technology, and in particular to a split-type suction anchor recovery device and method. Background Technology

[0002] The split-type suction anchor, also known as the mooring foundation based on suction barrel mud sinking penetration (CN116335187B), is an important mooring foundation for offshore floating platforms. It has the advantages of convenient installation, high load-bearing efficiency and strong environmental adaptability, and has broad application prospects in marine oil and gas and offshore new energy projects.

[0003] During its service life, the lower part of the split-type suction anchor is deeply buried in the seabed soil, taking full advantage of the high bearing capacity of the deep soil layer to provide a large mooring force for the offshore floating platform. However, after the service life ends, due to the deep burial of the anchor body and the strong adhesion and frictional resistance between it and the soil, the lifting load required for recovery is extremely large, often reaching hundreds or even thousands of tons.

[0004] Current recovery methods primarily rely on large-tonnage offshore cranes or jack-up platforms for overall lifting. This method makes it difficult to ensure alignment between the lifting point and the anchor's axis during lifting, easily leading to eccentric forces, which further increases the lifting load and structural stress risks. Furthermore, the anchor may tilt or shift due to environmental loads during long-term service, and current technologies lack methods for determining the anchor's spatial attitude based on stress information, as well as corresponding alignment adjustment capabilities.

[0005] Therefore, there is an urgent need for a split-type suction anchor recovery device and method that can align the lifting point with the anchor axis during the recovery process, identify the spatial posture of the anchor based on the force information, and adjust the position of the lifting point accordingly, thereby reducing the lifting load and improving the recovery safety. Summary of the Invention

[0006] The purpose of this invention is to provide a split-type suction anchor recovery device and method to solve the problems of large lifting load, difficulty in centering, inability to effectively handle anchor tilt, high operating costs and high safety risks when recovering split-type suction anchors buried deep in the seabed in the prior art.

[0007] The technical solution adopted in this invention is as follows:

[0008] A split-type suction anchor recovery device, characterized in that it comprises:

[0009] 1. Reaction Anchor

[0010] The reaction anchor is located at the bottom of the entire recovery device and is a suction structure. It creates an internal and external pressure difference by pumping in the internal water and embeds itself into the seabed to achieve fixed installation of the device.

[0011] 2. Supporting structure

[0012] The support structure is disposed above the reaction anchor and fixedly connected to it; the support structure is preferably a spatial frame structure composed of high-strength steel beams to enhance the overall rigidity and stability of the device; during the recovery process, when the anchor to be recovered is subjected to eccentric force, the support structure is used to bear the lateral component force generated therefrom.

[0013] 3. Initial alignment device

[0014] The initial alignment device includes a rotating device and a telescopic device; the rotating device is disposed between the reaction anchor and the telescopic device, and between the telescopic device and the secondary alignment device, for adjusting the angle of the superstructure and locking it after rotating to the target position; the telescopic device is disposed between the reaction anchor and the secondary alignment device for adjusting the radial position of the device; by rotating the rotating device and adjusting the length of the telescopic device, the secondary alignment device can be moved to directly above the anchor body to be retrieved, thereby achieving initial alignment.

[0015] 4. Secondary centering device

[0016] The secondary alignment device includes a frame, a longitudinal track, a transverse track, a driver, and a slider. The frame is mounted on the primary alignment device and serves as a mounting platform for the secondary alignment device. The longitudinal track is mounted on the frame and arranged longitudinally. The driver is mounted on the longitudinal track and can move along it. The transverse track is mounted on the driver and arranged transversely perpendicular to the longitudinal track. The slider is mounted on the transverse track and can move along it. The driver drives itself to move along the longitudinal track and drives the slider to move along the transverse track, thereby achieving fine adjustment of the lifting point in two mutually perpendicular directions. The lifting mechanism is mounted on the slider.

[0017] 5. Lifting mechanism

[0018] The lifting mechanism includes a motor and a lifting rope; the motor is mounted on the slider to provide lifting power; one end of the lifting rope is connected to the motor, and the other end is connected to the positioning rope to achieve traction of the anchor body to be retrieved.

[0019] 6. Positioning rope

[0020] The lower end of the positioning rope is connected to a lifting lug set on the anchor body to be retrieved; during the service of the suction anchor, the upper end of the positioning rope can be connected to a buoy for positioning the anchor body to be retrieved; during the retrieval process, the positioning rope is connected to the lifting rope for lifting and retrieving the anchor body.

[0021] 7. Tension sensor

[0022] The tension sensor is installed on the positioning rope and close to the lifting rope. The tension sensor is used to measure the tension on the positioning rope and characterize the spatial attitude characteristics of the anchor body to be retrieved based on the relative magnitude of the tension at different positions, thereby providing a basis for the selection of the lifting method.

[0023] 8. Anchor body and lifting lugs to be recovered

[0024] The anchor body to be recovered is located below the muddy surface of the seabed and is the load-bearing part of the split suction anchor; the lifting lug is set on the upper part of the anchor body to be recovered, used to achieve connection during the installation stage and as a lifting connection point during the recovery stage.

[0025] A method for recovering a split-type suction anchor based on the above-mentioned device includes:

[0026] (1) Determine the approximate location of the anchor to be retrieved using a positioning rope;

[0027] (2) The recovery device is hoisted to the target area and installed by embedding it into the seabed using a reaction anchor;

[0028] (3) Connect the lifting mechanism to the anchor body to be recovered;

[0029] (4) Coarse alignment is performed using the primary alignment device, and fine alignment is performed using the secondary alignment device, so that the lifting point is located above the anchor body to be recovered;

[0030] (5) Perform pre-lifting and acquire tension sensor data to determine the spatial attitude characteristics of the anchor body to be recovered and whether it meets the lifting conditions;

[0031] (6) When the anchor body to be recovered is determined to be in a spatial state that requires correction, the lifting point position is adjusted according to the judgment result, and the anchor body to be recovered is corrected.

[0032] (7) Start the lifting mechanism to complete the lifting and recovery of the anchor body to be recovered;

[0033] (8) After disconnecting the lifting mechanism from the anchor body to be recovered and disconnecting the reaction anchor from the seabed, remove the recovery device from the seabed.

[0034] In the method:

[0035] The tension information on the positioning rope is obtained by a tension sensor, and the position of the lifting point is adjusted based on the relative magnitude of the tension at different locations to determine whether the lifting point and the anchor axis can be basically coincident; the degree of deviation between the lifting point and the anchor axis is used to characterize the spatial attitude characteristics of the anchor; the spatial positional relationship between the recovery device and the anchor is determined based on the spatial attitude characteristics to determine whether the lifting path is restricted by the device structure.

[0036] When the lifting point is basically coincident with the axis of the anchor body and the lifting path is not restricted by the structure of the recovery device, it is determined to be in a state where it can be lifted directly; otherwise, it is determined to be in a state where correction is required.

[0037] Due to the adoption of the above technical solution, the beneficial effects achieved by this invention are as follows:

[0038] By setting up primary and secondary alignment devices, the lifting point can be adjusted in stages to improve alignment accuracy. By introducing tension data, the spatial attitude of the anchor body can be indirectly characterized, avoiding reliance on complex measuring equipment. At the same time, considering the conditions of axis coincidence and spatial constraints, a dual-criteria decision-making mechanism is established to improve the reliability of recovery judgment. When the lifting conditions are not met, correction processing is carried out to reduce the adverse effects of structural stress and improve the recovery success rate. The overall device structure is reasonable and suitable for suction anchor recovery operations under complex seabed conditions. Attached Figure Description

[0039] The accompanying drawings are provided to further understand the technical solutions of this invention and constitute a part of this specification. The illustrative embodiments and descriptions of this invention are for explaining the invention only and do not constitute a limitation on the scope of protection of this invention. In the drawings:

[0040] Figure 1 This is a front view of the overall structure of the present invention;

[0041] Figure 2 This is a top view of the overall structure of the present invention;

[0042] Figure 3 This is a front view of the secondary centering device of the present invention;

[0043] Figure 4 This is a top view of the secondary centering device of the present invention;

[0044] Figure 5 This is a schematic diagram of the recycling process of the present invention; wherein Figure 5 'a' represents the anchor body to be located and retrieved. Figure 5 b is for installing a recycling device; Figure 5 c represents the connection and alignment of the lifting ropes; Figure 5 d represents lifting and recovery;

[0045] Figure 6This is a schematic diagram illustrating the spatial state identification of the anchor body to be recovered according to the present invention; wherein Figure 6 a represents the untilted state (facing forward); Figure 6 b represents the state without tilt (translation); Figure 6 c represents the small tilt angle state (within the adjustment range); Figure 6 d represents the small tilt angle state (outside the adjustment range); Figure 6 e represents a large tilt angle;

[0046] Figure 7 This is a schematic diagram of the anchor body correction process to be recovered according to the present invention; wherein Figure 7 'a' represents reverse correction; Figure 7 b means lifting after correction.

[0047] The annotations in the attached figures are explained as follows:

[0048] 1—Reaction anchor;

[0049] 2—Supporting structure;

[0050] 3—Initial centering device; 31—Rotation device; 32—Telescopic device;

[0051] 4—Secondary centering device; 41—Frame; 42—Longitudinal track; 43—Driver; 44—Transverse track; 45—Slider;

[0052] 5—Lifting mechanism; 51—Motor; 52—Lifting rope;

[0053] 6—Positioning rope;

[0054] 7—Tension sensor;

[0055] 8—Anchor body to be recovered;

[0056] 9—Hanging lugs;

[0057] 10—Seabed. Detailed Implementation

[0058] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0059] Implementation Method 1: Overall Structure Description of the Device

[0060] This embodiment provides a split-type suction anchor recovery device, such as... Figures 1-4 As shown, it includes a reaction anchor 1, a support structure 2, a primary alignment device 3, a secondary alignment device 4, a lifting mechanism 5, a positioning rope 6, a tension sensor 7, an anchor body to be retrieved 8, a lifting lug 9, and the seabed 10.

[0061] Among them, the reaction anchor 1 is set in the seabed 10. According to the positioning rope 6, the position of the anchor body to be recovered 8 can be roughly located. Then, the water in the reaction anchor 1 is extracted and installed to the seabed by the pressure difference between the inside and outside, which can provide an upward reaction force for the entire recovery device.

[0062] The support structure 2 is set above the reaction anchor 1. The structure is composed of high-strength steel beams, which can enhance the integrity of the recovery device, ensure the stability of the recovery device during installation and use, and bear the lateral component force when the anchor body to be recovered is eccentrically loaded.

[0063] The initial alignment device 3 is installed on the support structure 2 and includes a rotating device 31 and a telescopic device 32, which are used to make coarse adjustments to the upper structure within a planar range.

[0064] The secondary alignment device 4 is installed on the primary alignment device 3 and includes a 41-frame, a 42-longitudinal track, a 43-driver, a 44-transverse track, and a 45-slider. The 41-frame is connected to the 31-telescopic device via a 32-rotating device and serves as the platform for the entire 4-secondary alignment device. The 42-longitudinal track is located at the lower part of the 41-frame and is arranged longitudinally. The 43-driver is located on the 42-longitudinal track and can drive itself to move longitudinally along the 42-longitudinal track, or drive the 45-slider to move laterally along the 44-transverse track. The 44-transverse track is arranged between the 43-drivers and is used to place the 45-slider. The 45-slider is arranged on the 44-transverse track and is used to connect the 44-transverse track to the 51-motor for fine adjustment of the lifting point position.

[0065] The lifting mechanism 5 is mounted on the secondary centering device 4 and includes a 51-motor and a 52-lifting rope. The 51-motor sits on the 45-slider and is used to pull the 52-lifting rope. The 52-lifting rope connects the 51-motor and the 6-positioning rope.

[0066] 6-Location rope, bottom connected to 9-Lifting lug. During normal service, the top of the 6-Location rope is attached to a buoy for positioning the 8-Anchor to be recovered; during recovery, the top of the 6-Location rope is connected to 52-Lifting rope. Used for lifting and recovering the 8-Anchor to be recovered.

[0067] 7-The tension sensor is located on 6-the positioning rope, near the 52-lifting rope side; it is used to measure the tension on 6-the positioning rope. Based on the tension, the spatial state of 8-the anchor body to be retrieved can be determined, and the appropriate lifting method can be selected accordingly.

[0068] 8-The anchor body to be recovered is located below the seabed mud surface mentioned in 10- and is the load-bearing part of the split suction anchor.

[0069] 9-The lifting lug is located above 8-the anchor body to be retrieved and connects to 6-the positioning rope. During the installation of the split-type suction anchor, it is used to ensure a tight connection between 8-the anchor body to be retrieved and the superstructure. During the retrieval of the split-type suction anchor, it is used to lift 8-the anchor body to be retrieved.

[0070] By coordinating and adjusting the primary centering device 3 and the secondary centering device 4, the lifting point of the lifting mechanism 5 is always located on the extended line of the axis of the anchor body 8 to be recovered during the recovery process, thereby avoiding eccentric force and reducing the lifting load.

[0071] Implementation Method Two: Overall Process of Recycling Method

[0072] This embodiment provides a method for recovering a split-type suction anchor based on the above-described device, the process of which is as follows: Figure 5 As shown, it includes the following steps:

[0073] (1) Determine the approximate location of the anchor to be retrieved using the positioning rope.

[0074] The approximate location of the anchor body 8 to be retrieved is determined by the buoy at the top of the positioning rope 6 connected to the anchor body 8 to be retrieved. Figure 5 a).

[0075] (2) Install recycling equipment

[0076] After the recovery device is hoisted to the target area by a ship crane, the water inside the reaction anchor 1 is pumped out, causing it to embed into the seabed 10, thus completing the installation of the recovery device. Figure 5 b).

[0077] (3) Connect the lifting mechanism to the anchor body to be recovered

[0078] The positioning rope 6 is connected to the lifting rope 52 in the lifting mechanism 5, thereby establishing the connection between the lifting mechanism and the anchor body 8 to be recovered. Figure 5 c).

[0079] (4) Adjustment in the middle

[0080] Coarse alignment is performed by the initial alignment device 3, and fine alignment is performed by the secondary alignment device 4, so that the lifting point of the lifting mechanism 5 is located above the anchor body 8 to be recovered. Figure 5 c)

[0081] The secondary centering device 4 is adjusted in a planar range by coordinating the rotating device 31 and the telescopic device 32. The longitudinal track 42, the transverse track 44, the driver 43 and the slider 45 in the secondary centering device 4 enable the lifting point to move precisely in two mutually perpendicular directions, thereby ensuring that the lifting point is always directly above the anchor body 8 to be retrieved during the lifting process.

[0082] (5) Spatial attitude recognition and lifting condition judgment

[0083] Start the lifting mechanism 5, tighten the lifting rope 52 to perform pre-lifting, and obtain the data from the tension sensor 7 on the positioning rope 6;

[0084] The lifting point position is adjusted based on the relative magnitude of the tension at different locations to determine whether the lifting point and the axis of the anchor body to be recovered can be basically coincident.

[0085] The degree of deviation between the lifting point and the axis of the anchor to be recovered is used to characterize the spatial attitude characteristics of the anchor to be recovered, and based on the spatial attitude characteristics, the spatial positional relationship between the recovery device and the anchor to be recovered is determined, thereby determining whether the lifting path is restricted by the structure of the recovery device, so as to determine whether the lifting conditions are met.

[0086] (6) Corrective measures

[0087] When the anchor body to be recovered is determined to be in a spatial state that requires correction, the lifting point position is adjusted according to the judgment result, and the anchor body to be recovered is corrected.

[0088] (7) Lifting and retrieving the anchor body

[0089] When the anchor body to be recovered meets the lifting conditions, the lifting mechanism 5 is activated to lift the anchor body 8 to be recovered to the designated position, thus completing the recovery. Figure 5 d).

[0090] (8) Recycling device

[0091] After the anchor body to be recovered is recovered, the connection between the lifting mechanism 5 and the anchor body to be recovered 8 is released; water is injected into the reaction anchor 1 to push it out of the seabed 10 in the opposite direction, so that the recovery device is detached from the seabed as a whole; then the recovery device is taken out of the seabed and recovered to the deck by the ship's crane.

[0092] Implementation Method 3: Implementation Process of the Centering Device

[0093] In practical engineering, the anchor body 8 to be recovered may undergo changes in spatial position and attitude due to long-term stress during service, thus requiring adjustment through a centering device (such as...). Figure 3-4 (as shown in the image) to ensure that the lifting point is always directly above it.

[0094] (1) Initial interaction with China

[0095] By extending and retracting the telescopic device 32 and rotating the rotating device 31, the secondary centering device 4 is positioned within the space, thereby moving as a whole to the area above the anchor body 8 to be retrieved, achieving initial centering.

[0096] (2) Secondary centering

[0097] After the initial alignment is completed, fine adjustment is performed by the secondary alignment device 4: when longitudinal adjustment is required, the driver 43 moves along the longitudinal track 42, driving the slider 45 and its lifting mechanism 5 to move longitudinally; when lateral adjustment is required, the driver 43 drives the slider 45 to move along the lateral track 44 to achieve lateral adjustment.

[0098] Through the above adjustments, the lifting point of the lifting mechanism 5 is kept directly above the anchor body 8 to be recovered during the lifting process.

[0099] Example 4: Implementation Process of Spatial State Identification for Anchors to be Recovered

[0100] In this embodiment, tensile data at different locations are obtained by a tensile sensor. When the tensile force at each measuring point tends to be consistent, it indicates that the lifting point and the anchor axis are basically coincident.

[0101] When the tension cannot be uniform, it indicates that there is a deviation between the lifting point and the anchor body axis, thus reflecting that the anchor body is tilted or eccentric.

[0102] By further considering the structural dimensions and relative positional relationships of the device, it can be determined whether the lifting path is restricted, thereby determining whether the anchor body is suitable for direct lifting.

[0103] In practical applications, based on the reading characteristics of the tension sensor 7 and the spatial relationship between the anchor to be recovered and the recovery device, the spatial state of the anchor to be recovered can be further subdivided into the following typical cases (such as...). Figure 6 (as shown)

[0104] (1) No tilt (center)

[0105] When all tension measurements are consistent, and the anchor to be recovered is located at the center of the horizontal projection of the recovery device, it is determined to be in a non-tilted state (center). Figure 6 a).

[0106] (2) No tilt state (translation)

[0107] When all tension measurements are consistent, but the anchor body to be recovered deviates from the horizontal projection center of the recovery device, it is determined to be in a state of no tilt (translation). Figure 6 b).

[0108] (3) Small tilt angle state (separated)

[0109] When adjustments can make the measured tension values ​​tend to be consistent, and the space formed by the extension of the anchor body axis to be recovered does not interfere with the recovery device, it is determined to be a small inclination angle state (separated). Figure 6 c).

[0110] (4) Small tilt angle state (intersection)

[0111] When adjustments can bring the measured tension values ​​closer to uniformity, but the space formed by the extension of the anchor body axis to be recovered interferes with the recovery device, it is determined to be a small inclination angle state (intersection). Figure 6 d).

[0112] (5) Large tilt angle state

[0113] When adjustments fail to bring the measured tension values ​​into agreement, the condition is determined to be a large tilt angle. Figure 6 e).

[0114] Furthermore, the above-mentioned states can be summarized as follows:

[0115] The states of no tilt (center), no tilt (translation), and small tilt angle (separation) correspond to the conditions that meet the lifting requirements.

[0116] The small tilt angle state (intersection) and the large tilt angle state correspond to the situations that require correction processing.

[0117] Implementation Method 5: Process of Correcting Anchor Body to be Recovered

[0118] For anchors to be recovered that are determined to require correction in either a small-angle (intersecting) or large-angle state, the following treatment should be performed (e.g. Figure 7 (as shown)

[0119] First, adjust the primary centering device 3 and the secondary centering device 4 so that the lifting point of the lifting mechanism 5 moves in the opposite direction of the anchor body's tilt.

[0120] Then, gradually tighten the lifting rope 52 to reduce the tilt angle of the anchor body to be retrieved;

[0121] Subsequently, the positions of the primary alignment device 3 and the secondary alignment device 4 are adjusted, and the relationship between the lifting point and the anchor axis is reassessed based on the reading of the tension sensor 7, and the spatial attitude characteristics are updated.

[0122] Repeat the above adjustment and evaluation process until the anchor to be recovered meets the lifting conditions, that is, the anchor to be recovered is adjusted to a state without tilt (center), a state without tilt (translation), or a state with a small tilt angle (separation).

[0123] Finally, the lifting point is adjusted to the extended line of the anchor body axis to complete the lifting and recovery.

Claims

1. A split-type suction anchor recovery device, characterized in that, include: A reaction anchor, placed in the seabed, is used to provide a reaction force during recovery. A support structure is provided above and connected to the reaction anchor; The initial alignment device is mounted on the supporting structure; A secondary centering device is installed on the primary centering device; a lifting mechanism is installed on the secondary centering device and connected to the anchor body to be retrieved. The primary centering device works in conjunction with the secondary centering device to adjust the lifting point position of the lifting mechanism, so that the lifting point remains on the extended axis of the anchor body to be recovered during the recovery process.

2. The recycling device according to claim 1, characterized in that: The reaction anchor is a suction structure that creates an internal and external pressure difference by drawing in internal water to embed itself into the seabed, thereby providing vertical reaction force.

3. The recycling device according to claim 1, characterized in that: The supporting structure is a steel frame structure used to support the primary centering device and the secondary centering device and to withstand the recovery load.

4. The recycling device according to claim 1, characterized in that: The initial alignment device includes a rotating device and a telescopic device. The rotating device is used to adjust the rotation of the device, and the telescopic device is used to adjust the length direction to achieve initial alignment of the lifting point.

5. The recycling device according to claim 1, characterized in that: The secondary centering device includes a frame, a longitudinal track disposed on the frame, a driver that can move along the longitudinal track and a transverse track, and a slider disposed on the transverse track and connected to the driver. The actuator is used to drive itself to move along the longitudinal track and to drive the slider to move along the transverse track, so as to adjust the position of the lifting point in two mutually perpendicular directions.

6. The recycling device according to claim 1, characterized in that: The lifting mechanism includes a motor and a lifting rope. The motor is mounted on the slider (45), and the slider is mounted on the secondary centering device to drive the lifting rope to lift the anchor body to be recovered.

7. The recycling device according to claim 1, characterized in that, Also includes: A positioning rope is attached to one end of the anchor body to be retrieved; a tension sensor is mounted on the positioning rope to acquire tension information, which is used to characterize the spatial attitude of the anchor body to be retrieved and to guide the adjustment of the lifting point position of the lifting mechanism.

8. A method for recovering a split-type suction anchor based on the recovery device according to any one of claims 1 to 7, characterized in that, Includes the following steps: (1) Determine the approximate location of the anchor to be retrieved using a positioning rope; (2) The recovery device is hoisted to the target area and installed by embedding it into the seabed using a reaction anchor; (3) Connect the lifting mechanism to the anchor body to be recovered; (4) Coarse alignment is performed using the primary alignment device, and fine alignment is performed using the secondary alignment device, so that the lifting point is located above the anchor body to be recovered; (5) Perform pre-lifting and acquire tension sensor data to determine the spatial attitude characteristics of the anchor body to be recovered and whether it meets the lifting conditions; (6) When the anchor body to be recovered is determined to be in a spatial state that requires correction, the lifting point position is adjusted according to the judgment result, and the anchor body to be recovered is corrected. (7) Start the lifting mechanism to complete the lifting and recovery of the anchor body to be recovered; (8) After disconnecting the lifting mechanism from the anchor body to be recovered and disconnecting the reaction anchor from the seabed, remove the recovery device from the seabed.

9. The method according to claim 8, characterized in that: Step 4 includes: coarse alignment by adjusting the rotational position and extension length of the device through the initial alignment device; and fine alignment by adjusting the position of the lifting point in two mutually perpendicular directions through the secondary alignment device.

10. The method according to claim 8, characterized in that: In step 5, the tension information on the positioning rope is obtained by the tension sensor, and the position of the lifting point is adjusted based on the relative magnitude of the tension at different positions to determine whether the lifting point and the axis of the anchor body to be recovered can be basically coincident. The degree of deviation between the lifting point and the axis of the anchor to be recovered is used to characterize the spatial attitude characteristics of the anchor to be recovered, and the spatial positional relationship between the recovery device and the anchor to be recovered is determined based on the spatial attitude characteristics, so as to determine whether the lifting path is restricted by the structure of the recovery device. Based on this, when the lifting point and the axis of the anchor body to be recovered can be basically coincided and the lifting path is not restricted by the structure of the recovery device, the anchor body to be recovered is determined to be in a spatial state that can be directly lifted. When the lifting point and the axis of the anchor to be recovered cannot be basically aligned, or although they can be basically aligned but the lifting path is restricted by the structure of the recovery device, it is determined that the anchor to be recovered is in a spatial state that requires correction. For the spatial state that requires correction, the lifting point is moved in the opposite direction of the tilt direction of the anchor to be recovered; the lifting rope is gradually tightened to reduce the tilt of the anchor to be recovered; and the adjustment is repeated in combination with the tension sensor data until the lifting conditions are met.

Images