A large-grab anchor and a method for precise laying and tensioning of a large-diameter anchor chain

Abstract

This invention provides a method for the precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains, specifically including: S1, pre-laying of anchor chains; S2, designing and laying anchor points around the center of the aquaculture cage installation location; S3, the process of lowering the high-holding-force anchor and laying the corresponding anchor chain at each anchor point specifically includes: (1) positioning the chain exit point on the side of the ship above the anchor point; (2) hoisting the high-holding-force anchor overboard to the chain exit point on the side of the ship; (3) releasing the anchor chain by a winch to lower the high-holding-force anchor and anchor chain to the seabed, with the winch using a cyclic release method; (4) moving the engineering vessel along the anchor chain line to lay the anchor chain along the anchor chain line; (5) tensioning the anchor chain, monitoring the tension by a tension gauge until it reaches 125 tons to meet the requirements; (6) installing positioning beacons at the ends of the high-holding-force anchor and anchor chain. This invention solves the problems of deviation and bending in existing anchor chain laying methods, and the anchoring accuracy being easily affected by external wind and current.

Description

Technical Field

[0001] This invention relates to the field of aquaculture cage installation technology, and more specifically, to a method for the precise laying and tensioning of a high-holding-force anchor and a large-diameter anchor chain. Background Technology

[0002] In the field of aquaculture cage installation, the laying of large-diameter anchor chains must not only meet the technical requirements of free lifting and lowering of the aquaculture cages, but also avoid the cages and underwater anchor chains from tangling. The laid anchor chains must also meet the specified tension requirements. However, the existing anchor chain laying methods are prone to deviation and bending, and the anchoring accuracy is easily affected by external wind flow, resulting in the suspension chain tension not being guaranteed. In addition, an additional construction mother ship is required during the construction process to place the linear winch, which affects the construction efficiency. Summary of the Invention

[0003] In response to the aforementioned technical problems of deviations and bending in existing anchor chain laying methods, and the ease with which anchoring accuracy is affected by external wind flow, a method for precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains is provided.

[0004] The technical means employed in this invention are as follows:

[0005] A method for precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains specifically includes the following steps:

[0006] S1. Anchor chain pre-laying: On the engineering vessel, complete the deck laying of four anchor chains and four high-holding-power anchors, and connect the four anchor chains to the four positioning anchors one-to-one.

[0007] S2. Design four anchor points with high holding power around the center of the aquaculture cage installation location, and label them as anchor points 1, 2, 3 and 4 in sequence. The line connecting each anchor point to the center of the aquaculture cage installation location is the anchor chain line for laying anchor chains. The four anchor chain lines are of equal length.

[0008] S3. After the tugboat tows the engineering vessel to the construction site, the high-holding-force anchors and corresponding anchor chains are laid at each anchoring point in a clockwise or counterclockwise order.

[0009] The specific process of lowering high-holding-force anchors and laying corresponding anchor chains at each anchoring point includes:

[0010] (1) The tugboat tows the engineering vessel to the location of the anchoring point. The tugboat assists the engineering vessel in anchoring around the anchoring point. Then, by winding up the anchor wire of the engineering vessel, the side chain exit point of the corresponding anchor chain of the large holding anchor to be lowered on the engineering vessel is located above the anchoring point.

[0011] (2) The tugboat approaches the side of the chain exit point of the corresponding anchor chain of the large holding anchor to be lowered on the engineering vessel. The crane on the engineering vessel is connected to the corresponding anchor chain of the large holding anchor to be lowered through a steel cable. The large holding anchor is lifted out of the ship and placed at the side of the chain exit point. The steel cable installed on the back plate of the large holding anchor head is connected to the stern of the tugboat through a traction steel wire. The large holding anchor is affected by its own center of gravity and its attitude is adjusted to the anchor claws facing down. Then the steel cable connecting the crane and the anchor chain is untied.

[0012] (3) The anchor chain is released by the winch on the engineering vessel to lower the anchor with the anchor chain to the seabed. The winch releases the anchor chain in a cyclic release manner, releasing 30 meters of anchor chain in each cycle. The position of the tugboat is controlled to keep the traction steel wire stable during the lowering process of the anchor with the anchor claws facing down, so as to ensure that the anchor with the anchor can land upright and grab the seabed at the anchoring point.

[0013] (4) Move the engineering vessel along the anchor chain line toward the center of the aquaculture cage installation location, and release the anchor chain through the winch on the engineering vessel to lay the anchor chain along the anchor chain line; when the total length of the anchor chain lowered reaches 150m, the anchor chain is tensioned once, and then tensioned every 50m of anchor chain released thereafter, until the entire anchor chain is laid along the anchor chain line; the anchor chain is tensioned by using the ratchet wheel of the winch to brake the anchor chain and continuously apply force, and tensioning the anchor chain as the engineering vessel moves along the anchor chain line;

[0014] (5) Tension and tension test on the laid anchor chain: Connect a tension gauge between the steel cable of the winch and the anchor chain at the end of the laid anchor chain. Before tensioning the anchor chain, the engineering vessel stops moving and brakes the winch. Then, by winding the anchor wire on the engineering vessel that is on a different side from the anchor chain, and at the same time loosening the anchor wire that is on the same side as the anchor chain, the anchor chain is tensioned.

[0015] When the tension of the anchor chain reaches 125 tons by monitoring with a tension gauge, it means that the tension of the anchor chain meets the requirements. Then, by winding up the anchor wire on the same side as the anchor chain on the engineering vessel, while simultaneously loosening the anchor wire on the opposite side of the anchor chain, the tensioned anchor chain is loosened.

[0016] (6) Install a positioning beacon on the anchor eye plate of the high holding power anchor and at the end of the anchor chain to detect the position of the high holding power anchor and the end of the anchor chain, and determine whether there is a deviation in the direction of the anchor chain laying or the anchor chain stacking based on the detected position of the high holding power anchor and the end of the anchor chain.

[0017] Furthermore, the anchor with high holding power has a weight of 18T; the anchor chain diameter is 105mm, the weight per meter of the anchor chain is 224kg, and the length of each anchor chain is 445m.

[0018] Further, step S1 specifically includes: at the dock, using a crane on the engineering vessel, first placing four anchor chains and four high-holding-power anchors on the deck of the engineering vessel, and laying each anchor chain in a serpentine pattern along the width of the deck, placing the high-holding-power anchors with their claws facing upwards on the deck of the engineering vessel, and then connecting the four anchor chains one-to-one with the four positioning anchors; then connecting a steel cable to each of the two backplates of the high-holding-power anchor head through connecting shackles, in preparation for the subsequent laying of anchor chains and ensuring the positive landing of the high-holding-power anchors.

[0019] Further, in step S3(1), the error between the chain exit point on the side of the ship and the anchor placement point is (-25m, +10m), with the negative value being the side closer to the aquaculture cage installation position when the chain exit point on the side of the ship is located on the straight line of the anchor chain line.

[0020] Furthermore, in step S3 (6), shackles are installed on the anchor bolt eye plate and the end of the anchor chain of the high holding power anchor, and the nylon ropes of the corresponding positioning beacons are passed through the shackles and fixed to the stern of the tugboat and the side of the engineering vessel, respectively.

[0021] Further, in step S3(3), when releasing the anchor chain by the winch, in each cycle: first, the winch cable is connected to the anchor chain, and the operation of the winch is controlled to release the anchor chain. When the anchor chain is released for 30 meters, the connection between the winch cable and the anchor chain reaches the guide bollard on the side of the engineering vessel. Then, the connection between the anchor chain and the winch cable is connected to the grounding wire on the deck of the engineering vessel through a steel wire, and the connection between the winch cable and the anchor chain is released, and the next cycle of releasing the anchor chain begins.

[0022] Furthermore, step S3(3) also includes: marking a specified length from the installation position of the steel cable on the back plate of the anchor head at one end of the anchor chain connected to the high holding power anchor; based on the water depth at the anchoring point, the length of the anchor chain that needs to be released to lower the high holding power anchor to the seabed at the anchoring point can be determined by the mark on the anchor chain.

[0023] Furthermore, in step S3(4), after the high-holding anchor has been secured to the seabed, when releasing the 30m-50m anchor chain, the anchor chain is pulled by a winch on the engineering vessel to confirm whether the high-holding anchor has been secured to the seabed. After confirming that it has been secured to the seabed, the anchor chain laying continues.

[0024] Furthermore, a 2-ton buoy was connected to the end of the anchor chain after the tension and strain tests were completed, and the buoy was then launched into the sea.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] The present invention provides a method for the precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains. Using an engineering vessel, the high-holding-force anchors and anchor chains are precisely laid and tensioned, ensuring a smooth positive landing of the high-holding-force anchors. Furthermore, the method meets the 125t tensile test requirements for anchor chains connecting aquaculture cages without a tightening device. The construction process is stable, less affected by on-site wind, waves, and currents, and avoids the need for multiple trips to the site and dock for loading and unloading that would occur with tugboats, thus saving operation time.

[0027] Based on the above reasons, this invention can be widely promoted in the field of aquaculture cage installation. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the engineering vessel in place.

[0030] Figure 2 A schematic diagram showing the arrival and anchoring points of the engineering vessel.

[0031] Figure 3 This is a schematic diagram showing the connection between a high-holding-force anchor and a tugboat's traction wire.

[0032] Figure 4 (1)-(3) are schematic diagrams of the process of amplifying the holding anchor under the cyclic release of the anchor chain.

[0033] Figure 5 (1)-(3) are schematic diagrams of the anchor chain laying process.

[0034] Figure 6 This is a schematic diagram of the anchor chain tensioning operation. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1

[0037] like Figure 1 As shown, this invention provides a method for the precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains. In this embodiment, the aquaculture cage is a deep-sea aquaculture cage, and the specific steps include:

[0038] S1. Anchor chain pre-laying: On the engineering vessel, complete the deck laying of four anchor chains and four high-holding-power anchors, and connect the four anchor chains to the four positioning anchors one-to-one.

[0039] S2. Design four anchor points with high holding power around the center of the aquaculture cage installation location, and label them as anchor points 1, 2, 3 and 4 in sequence. The line connecting each anchor point to the center of the aquaculture cage installation location is the anchor chain line for laying anchor chains. The four anchor chain lines are of equal length.

[0040] S3. After the tugboat tows the engineering vessel to the construction site, the high-holding-force anchors and corresponding anchor chains are laid at each anchoring point in a clockwise or counterclockwise order. The order of laying the high-holding-force anchors and anchor chains (clockwise or counterclockwise) can be determined according to the wind and current conditions at the site. The characteristics of the assisting vessel being easier to operate with the current and downstream than with the cross current should be fully considered to avoid the danger of interference between the two vessels due to an unsuitable angle between the tugboat and the engineering vessel when pulling the anchor.

[0041] The specific process of lowering high-holding-force anchors and laying corresponding anchor chains at each anchoring point includes:

[0042] (1) The tugboat tows the engineering vessel to the location of the anchoring point. The tugboat assists the engineering vessel in anchoring around the anchoring point. The engineering vessel must lay at least 6 anchors. Then, by winding up the anchor wire of the engineering vessel, the side of the chain of the anchor chain of the large holding anchor to be lowered on the engineering vessel is located above the anchoring point.

[0043] (2) The tugboat is maneuvered to approach the side of the anchor chain of the large holding anchor to be lowered on the engineering vessel. The crane on the engineering vessel is connected to the corresponding anchor chain of the large holding anchor to be lowered via a steel cable (the connecting steel cable is φ38mm and 80m long, and is connected to the anchor chain at a position about 25m away from the large holding anchor via a shackle of 85T). The large holding anchor is lifted out of the ship and placed at the side of the anchor chain. The steel cable (φ38mm and 20m long, two cables) installed on the back plate of the large holding anchor head is connected to the stern of the tugboat via a traction steel wire (φ60mm and 75m long) (the traction steel wire is connected to the stern of the tugboat via a shackle of 55T). The large holding anchor is affected by its own center of gravity and its attitude is adjusted so that the anchor claws face down. Then the steel cable connecting the crane and the anchor chain is untied.

[0044] (3) The anchor chain is released by the winch (80t) on the engineering vessel to lower the anchor with the anchor chain to the seabed. The winch releases the anchor chain in a cyclic manner, releasing 30 meters of anchor chain in each cycle, so that the anchor with ...

[0045] The present invention ensures that the chain exit point on the side of the engineering vessel is as close as possible to the anchor placement point through step (2), and combined with the method of step (3), the large holding anchor can ensure that the distance error between the landing point of the large holding anchor and the anchor placement point is (-25m, +10m), with the negative value being the side closer to the aquaculture cage installation position when the landing point of the large holding anchor is on the straight line of the anchor chain line.

[0046] (4) The engineering vessel moves along the anchor chain line toward the center of the aquaculture cage installation location, and at the same time, the anchor chain is released by the winch on the engineering vessel, so that the anchor chain is laid along the anchor chain line; when the total length of the anchor chain is lowered reaches 150m, the anchor chain is tensioned once, and then the anchor chain is tensioned every 50m of anchor chain released thereafter, until the entire anchor chain is laid along the anchor chain line, so as to ensure that the anchor chain is laid in a straight line, indirectly solving the problem of anchor chain deviation and bending; the anchor chain is tensioned by using the ratchet wheel of the winch to brake the anchor chain and continuously apply force, and the anchor chain is tensioned as the engineering vessel moves along the anchor chain line;

[0047] During the anchoring process, the engineering vessel needs to be precisely maneuvered to ensure that it always travels along the anchor chain line without too much deviation, to avoid large lateral movement of the anchor chain and to prevent the anchor chain from piling up, thus laying a good foundation for the subsequent tensioning of the anchor chain and connection of the gabion.

[0048] (5) Tension and tension test of the laid anchor chain: Connect a tension gauge between the steel cable of the winch at the end of the anchor chain and the anchor chain. Before tensioning the anchor chain, the engineering vessel stops moving and brakes the winch. Then, the anchor steel wire on the engineering vessel located on a different side from the anchor chain is wound up, while the anchor steel wire on the same side as the anchor chain is loosened to achieve tension of the anchor chain. The tension gauge is installed between the steel cable of the winch and the anchor chain through two 120T shackles, and a swivel is connected in the middle to prevent the steel cable from twisting during tensioning.

[0049] When the tension of the anchor chain reaches 125 tons by monitoring with a tension gauge, it means that the tension of the anchor chain meets the requirements. Then, by winding up the anchor wire on the same side as the anchor chain on the engineering vessel, while simultaneously loosening the anchor wire on the opposite side of the anchor chain, the tensioned anchor chain is loosened.

[0050] (6) Install a positioning beacon on the anchor eye plate of the high holding power anchor and at the end of the anchor chain (the end closest to the aquaculture cage installation location after laying) to detect the position of the high holding power anchor and the end of the anchor chain, and determine whether there is a directional deviation or stacking of the anchor chain based on the detected position of the high holding power anchor and the end of the anchor chain.

[0051] Further, step S1 specifically includes: at the dock, using the crane on the engineering vessel, first placing four anchor chains and four high-holding-force anchors on the deck of the engineering vessel, and laying each anchor chain in a serpentine pattern along the width of the deck, placing the high-holding-force anchors with their claws facing upwards on the deck of the engineering vessel, and then connecting the four anchor chains one-to-one with the four positioning anchors; then connecting a φ38mm steel cable with a length of 20m to each of the two back plates of the high-holding-force anchor head through connecting shackles (35T), in preparation for the subsequent laying of anchor chains and ensuring the positive landing of the high-holding-force anchors.

[0052] Furthermore, the anchor with high holding capacity has a weight of 18T; the anchor chain diameter is 105mm, the weight per meter of the anchor chain is 224kg, and the length of each anchor chain is 445m; in step S1, when using a crane, a short crane cable with sufficient safety load should be selected, and a small forklift and the two main hooks and four auxiliary hooks of the crane should work together to lift the anchor chain and lay it on the deck; the anchor chain should not be stacked on the deck to avoid affecting the deck operation when anchoring.

[0053] Furthermore, step S1 can also be adjusted according to the actual layout. If the deck space of the engineering vessel is insufficient to complete the pre-connection of the anchor chain and the high-holding-force anchor, then on-site connection of the anchor chain and the high-holding-force anchor can be considered.

[0054] Furthermore, in step S3(1), the error in the distance between the chain exit point on the side and the anchor placement point is (-25m, +10m), with the negative value being the side closer to the aquaculture cage installation position when the chain exit point on the side is located on the straight line of the anchor chain. The error in the distance between the chain exit point on the side and the anchor placement point can be monitored by the positioning equipment on the engineering vessel.

[0055] Further, in step S3 (6), shackles are installed on the anchor bolt eye plate of the high-holding-force anchor and at the end of the anchor chain (the end closest to the aquaculture cage installation location after laying). The nylon rope (φ30mm, length 200m) of the corresponding positioning beacon is passed through the shackles and fixed to the stern of the tugboat and the side of the engineering vessel, respectively. After the anchor chain is tensioned, the tugboat detects the position of the high-holding-force anchor through the positioning beacon on the high-holding-force anchor. After the engineering vessel lowers the end of the anchor chain to the seabed using a φ38mm steel cable, it detects the position of the end of the anchor chain through the positioning beacon installed at the end of the anchor chain. The anchor chain is positioned and the location of the high-holding anchor and the end of the anchor chain are detected to determine whether there is a directional deviation or anchor chain stacking during the anchor chain laying process. By combining the actual length of the anchor chain and the location of the anchor points, the position of the end of the anchor chain after laying can be predicted. By comparing the detected position of the end of the anchor chain with the predicted position, it can be determined whether there is a deviation in the anchor chain laying process. The distance between the detected high-holding anchor and the end of the anchor chain can be obtained. By comparing it with the actual length of the anchor chain, it can be determined whether anchor chain stacking has occurred during the anchor chain laying process.

[0056] Further, in step S3(3), when releasing the anchor chain by the winch, in each cycle: first, the winch cable is connected to the anchor chain, and the operation of the winch is controlled to release the anchor chain. When the anchor chain is released for 30 meters, the connection between the winch cable and the anchor chain reaches the guide bollard on the side of the engineering vessel. Then, the connection between the anchor chain and the winch cable is connected to the grounding wire on the deck of the engineering vessel through a steel wire, and the connection between the winch cable and the anchor chain is released, and the next cycle of releasing the anchor chain begins.

[0057] Furthermore, step S3(3) also includes: marking a point at a specified length (10 meters) from the installation position of the steel cable on the back plate of the anchor head of the anchor chain at the end of the anchor chain connected to the high holding power anchor; based on the water depth at the anchoring point, the length of the anchor chain to be released to bring the high holding power anchor to the seabed at the anchoring point can be determined by the mark on the anchor chain, thereby releasing the anchor chain by precisely controlling the operation of the winch, maneuvering the vessel to make the chain exit point on the side of the engineering vessel as close as possible to the designated anchoring point, and coordinating the control of the two vessels to ensure that the error between the landing point of the high holding power anchor and the anchoring point is (-25m, +10m), with the negative value being the side closer to the installation position of the aquaculture cage when the landing point of the high holding power anchor is on the straight line of the anchor chain line.

[0058] Furthermore, in step S3(4), when the engineering vessel lays the anchor chain, the anchor wire of the engineering vessel is wound up to ensure that the engineering vessel moves along the anchor chain line and the chain exit point on the side remains above the anchor chain line.

[0059] Furthermore, in step S3(4), after the high-holding anchor has been secured to the seabed, when releasing 30m-50m of anchor chain (taking a water depth of 56m as an example, about 100m of anchor chain is released in this step), the anchor chain is pulled by a winch on the engineering vessel to confirm whether the high-holding anchor has been secured to the seabed. After confirming that it has been secured to the seabed, the anchor chain laying continues.

[0060] Furthermore, in step S3, if it is found that the landing point of the high-holding anchor does not meet the requirements, or the laying of the anchor chain does not meet the requirements, the tugboat can assist in the recovery of the high-holding anchor, and the lowering of the high-holding anchor and the laying of the anchor chain can be repeated until the requirements are met.

[0061] Furthermore, after completing the tension and strain tests, the anchor chain is pulled back 50m by the engineering vessel to create a bend, providing clear space for the cages to be brought in and connected.

[0062] Furthermore, a 2-ton buoy is connected to the end of the anchor chain after the tension and strain tests are completed via a short steel cable (φ38mm, 80m in length), and the buoy is then launched into the sea. The buoy is used to provide a position marker for the subsequent installation of aquaculture cages and connection of the anchor chain.

[0063] Furthermore, after each high-holding-force anchor is lowered and the corresponding anchor chain is laid and tensioned, the engineering vessel rotates its bow 90° and repeats the same process at other anchoring points to lower high-holding-force anchors and lay and tension the corresponding anchor chains.

[0064] Furthermore, the tensioning method for each anchor chain is as described in step S3(5).

[0065] This invention utilizes engineering vessels for operations, offering the following advantages:

[0066] First, it has a large deck area, which allows for the orderly arrangement and pre-laying of all four anchor chains and high holding power anchors. It also provides a large space for personnel to work on the deck, avoiding the need for multiple trips between the site and the dock for loading and unloading that would occur when using tugboats, thus greatly saving working time.

[0067] Secondly, the construction process is relatively stable by using cranes and winches to drive the laying and tensioning of anchor chains. It is less affected by on-site wind, waves and currents, which improves the method of tensioning by tugboats using motorized vehicles and also saves tugboat fuel costs.

[0068] Third, the deck can be equipped with cranes and numerous deck machinery for auxiliary support, which is extremely convenient for lowering large-diameter anchor chains.

[0069] The method for precise laying and tensioning of large-holding anchors and large-diameter anchor chains described in this invention can successfully achieve the requirements for positive landing of large-holding anchors and 125T tensile test, and solve the problems of anchor chain laying deviation and bending in aquaculture cages. At the same time, it solves the problem of the influence of external airflow on anchoring accuracy.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains, characterized in that, Specifically, the following steps are included: S1. Anchor Chain Pre-laying: On the engineering vessel, the deck laying of four anchor chains and four high-holding-power anchors is completed, and the four anchor chains are connected one-to-one with the four high-holding-power anchors. This includes: at the dock, using the crane on the engineering vessel, the four anchor chains and four high-holding-power anchors are first placed on the deck of the engineering vessel, and each anchor chain is laid in a serpentine pattern along the width of the deck. The high-holding-power anchors are placed on the deck of the engineering vessel with their claws facing upwards. Then, the four anchor chains are connected one-to-one with the four high-holding-power anchors. Then, a steel cable is connected to each of the two backplates of the anchor head of the high-holding-power anchors through connecting shackles to prepare for the subsequent anchor chain laying and to ensure the positive landing of the high-holding-power anchors. S2. Design four anchor points with high holding power around the center of the aquaculture cage installation location, and label them as anchor points 1, 2, 3 and 4 in sequence. The line connecting each anchor point to the center of the aquaculture cage installation location is the anchor chain line for laying anchor chains. The four anchor chain lines are of equal length. S3. After the tugboat tows the engineering vessel to the construction site, the high-holding-force anchors and corresponding anchor chains are laid at each anchoring point in a clockwise or counterclockwise order. The specific process of lowering high-holding-force anchors and laying corresponding anchor chains at each anchoring point includes: (1) The tugboat tows the engineering vessel to the location of the anchoring point. The tugboat assists the engineering vessel in anchoring around the anchoring point. Then, by winding the anchor wire of the engineering vessel, the side chain exit point of the corresponding anchor chain of the high holding power anchor to be lowered on the engineering vessel is located above the anchoring point. The error between the side chain exit point and the anchoring point is (-25m, +10m), with the negative value being the side closer to the aquaculture cage installation position when the side chain exit point is on the straight line of the anchor chain line. (2) The tugboat approaches the side of the chain exit point of the corresponding anchor chain of the large holding anchor to be lowered on the engineering vessel. The crane on the engineering vessel is connected to the corresponding anchor chain of the large holding anchor to be lowered through a steel cable. The large holding anchor is lifted out of the ship and placed at the side of the chain exit point. The steel cable installed on the back plate of the large holding anchor head is connected to the stern of the tugboat through a traction steel wire. The large holding anchor is affected by its own center of gravity and its attitude is adjusted to the anchor claws facing down. Then the steel cable connecting the crane and the anchor chain is untied. (3) The anchor chain is released by the winch on the engineering vessel, allowing the high-holding-power anchor and anchor chain to be lowered to the seabed. The winch releases the anchor chain in a cyclical manner, releasing 30 meters of anchor chain in each cycle. The position of the tugboat is controlled to stabilize the attitude of the high-holding-power anchor during the lowering process, keeping the anchor claws facing downwards, thus ensuring that the high-holding-power anchor lands upright at the anchoring point and grips the seabed. When releasing the anchor chain by the winch, in each cycle: first, the winch cable is connected to the anchor chain, and the operation of the winch is controlled to release the anchor chain. When 30 meters of anchor chain are released... At this point, the connection between the winch cable and the anchor chain reaches the guide bollard on the side of the engineering vessel. Then, the connection between the anchor chain and the winch cable is connected to the ground anchor on the deck of the engineering vessel via a steel wire, and the connection between the winch cable and the anchor chain is released, entering the next cycle of releasing the anchor chain. At the end of the anchor chain connected to the high-holding-power anchor, a mark is made at a specified length from the installation position of the steel cable on the back plate of the high-holding-power anchor head. Based on the water depth at the anchoring point, the length of the anchor chain that needs to be released to lower the high-holding-power anchor to the seabed at the anchoring point can be determined by the mark on the anchor chain. (4) The engineering vessel moves along the anchor chain line toward the center of the aquaculture cage installation location, and at the same time releases the anchor chain through the winch on the engineering vessel, so that the anchor chain is laid along the anchor chain line; when the total length of the anchor chain reaches 150m, the anchor chain is tensioned once, and then tensioned every 50m of anchor chain is released thereafter, until the entire anchor chain is laid along the anchor chain line; the anchor chain is tensioned by using the ratchet wheel of the winch to brake the anchor chain and continuously apply force, and tensioning the anchor chain as the engineering vessel moves along the anchor chain line; after the high holding power anchor has entered the seabed, when releasing another 30m-50m of anchor chain, the engineering vessel uses the winch to pull the anchor chain to confirm whether the high holding power anchor has entered the seabed, and continues to lay the anchor chain after confirming that it has entered the seabed; (5) Perform tension and tension test on the laid anchor chain: Connect a tension gauge between the steel cable of the winch and the anchor chain. Before tensioning the anchor chain, the engineering vessel stops moving and brakes the winch. Then, by winding the anchor wire on the engineering vessel that is on a different side from the anchor chain, and at the same time loosening the anchor wire that is on the same side as the anchor chain, the anchor chain is tensioned. When the tension of the anchor chain reaches 125 tons by monitoring with a tension gauge, it means that the tension of the anchor chain meets the requirements. Then, by winding up the anchor wire on the same side as the anchor chain on the engineering vessel, while simultaneously loosening the anchor wire on the opposite side of the anchor chain, the tensioned anchor chain is loosened. (6) Install a positioning beacon on the anchor eye plate and the end of the anchor chain of the high holding power anchor to detect the position of the high holding power anchor and the end of the anchor chain, and determine whether there is a deviation in the direction of the anchor chain or the anchor chain stacking based on the detected position of the high holding power anchor and the end of the anchor chain. The anchor with high holding capacity has a weight of 18T; the anchor chain diameter is 105mm, the weight per meter of the anchor chain is 224kg, and the length of each anchor chain is 445m.

2. The method for precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains according to claim 1, characterized in that, In step (6) of step S3, shackles are installed on the anchor bolt eye plate and the end of the anchor chain of the high holding power anchor, respectively. The nylon rope of the corresponding positioning beacon is passed through the shackle and fixed to the stern of the tugboat and the side of the engineering vessel.

3. The method for precise laying and tensioning of high-holding-force anchors and large-diameter anchor chains according to claim 1, characterized in that, After completing the tension and stress tests, a 2-ton buoy is connected to the end of the anchor chain via a short steel cable, and the buoy is then launched into the sea.

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