Ship anchor cable machine constant tension mooring device and test method

Abstract

The invention relates to the technical field of ship mooring tests, and discloses a ship anchor cable machine constant tension mooring device and a test method.The ship anchor cable machine constant tension mooring device comprises a plurality of ship-borne anchor cable machines, each ship-borne anchor cable machine comprises a mooring cable, a driving device and an anchor cable machine body, the mooring cable is wound around the anchor cable machine body, and the driving device is in transmission connection with the anchor cable machine body; each shipborne anchor cable machine is provided with a tension detection unit and a stroke detection unit; the on-board mooring bollard comprises a bow mooring bollard and a stern mooring bollard. Wherein the bow mooring bollard and the stern mooring bollard are symmetrically arranged in the head-tail direction of the ship; each wharf bollard is used for fixing the free end of the mooring rope; and the central controller is electrically connected with all the driving devices, the tension detection unit and the stroke detection unit. According to the ship anchor cable machine constant tension mooring device and the test method, a plurality of mooring cables are symmetrically arranged end to end and are synchronously linked with the central controller, so that a safe, efficient and high-precision constant tension mooring test is realized.

Description

Technical Field

[0001] This invention relates to the technical field of ship mooring tests, and in particular to a constant tension mooring device for ship anchor winches and a test method. Background Technology

[0002] Ship mooring systems are crucial equipment for ensuring the safety of ships berthed at docks. With the increasing size of ships and the growing complexity of the marine environment, traditional mooring methods are susceptible to multi-directional movements such as rolling, pitching, and heaving under the influence of wind, waves, currents, and tides. This leads to sudden changes in cable tension and a significant increase in the risk of cable breakage. To address this, constant tension mooring systems have emerged. By monitoring and automatically adjusting cable tension in real time, these systems maintain the cables within a preset constant tension range, thereby improving mooring safety and stability.

[0003] Existing constant tension mooring systems are mostly ship-mounted independent control units, with each anchor winch operating independently, lacking integrated design for wharf facilities and a multi-machine collaborative control mechanism. During ship mooring tests, the lack of a unified control interface and collaborative control algorithm, coupled with independent tension adjustment of each cable, makes it difficult to maintain overall tension balance under tidal changes. Furthermore, limitations imposed by the wharf bollard arrangement result in significant differences in cable length, particularly in the bow and stern cross cables, leading to poor resistance to lateral forces and large variations in cable stress during testing, increasing the risk of cable breakage. Therefore, to ensure safety, current technologies can only employ a "single-machine or batch, long-term, manually monitored" testing mode, typically requiring multiple tests in batches, each lasting 6 hours. This results in low testing efficiency, high labor costs, and an inability to realistically simulate the actual mooring conditions of a ship under the coordinated action of multiple cables. Summary of the Invention

[0004] The invention aims to solve at least one of the technical problems existing in the prior art. It provides a constant tension mooring device and testing method for ship anchor winches, which achieves safe, efficient, and high-precision constant tension mooring tests for multiple shipborne anchor winches by symmetrically arranging multiple mooring lines end-to-end and synchronously linking them with a central controller.

[0005] To achieve the above objectives, the present invention provides a constant tension mooring device for ship anchor winches, comprising: Multiple shipborne anchor winches are distributed in the bow and stern areas of the ship. Each shipborne anchor winch includes a mooring line, a drive unit, and an anchor winch body for fixing to the ship's deck. The mooring line is wound around the anchor winch body, and the drive unit is connected to the anchor winch body for transmission. Each of the shipborne anchor winches is equipped with a tension detection unit for real-time acquisition of tension data of the corresponding mooring line and a stroke detection unit for real-time acquisition of the take-up and release length and speed data of the corresponding mooring line. Shipboard bollards are used to secure the ship to its deck, including bow bollards and stern bollards; wherein the bow bollards and the stern bollards are arranged symmetrically along the bow and stern direction of the ship. Multiple dock bollards are used to secure the ship to the dock, and each of the dock bollards is used to secure the free end of a mooring line at a position corresponding to a position after being guided by the bollard on the ship. The central controller is electrically connected to all the drive devices, the tension detection unit, and the stroke detection unit.

[0006] As a preferred embodiment, the mooring line between the ship's bollard and the dock bollard forms a line segment, and the line segment forms an angle α with the ship's longitudinal axis, the angle α being set in the range of 45°-60°.

[0007] As a preferred embodiment, the multiple wharf bollards are arranged at intervals, with the interval between adjacent wharf bollards being 3m-8m.

[0008] As a preferred embodiment, the bow bollard includes a port bow bollard, a starboard bow bollard, and a bow center bollard, and the stern bollard includes a port stern bollard, a starboard stern bollard, and a stern center bollard.

[0009] A test method for a ship's anchor winch constant tension mooring device, comprising the following steps: Mooring and parameter setting steps: Wind one end of the mooring line around the ship's anchor winch body, and then guide the other end through the ship's mooring bollards and fix it to the corresponding dock bollards in sequence, so that the fixed mooring lines are arranged in an engineering symmetrical manner relative to the ship's longitudinal axis, and at the same time set the test tension range. Synchronous start-up test procedure: The central controller simultaneously sends a start command to the drive device of all shipborne anchor winches to make the shipborne anchor winches work. Adaptive constant tension control steps: During tidal changes, the central controller adjusts the drive devices of each shipborne anchor winch according to the deviation between the tension data of each mooring line collected in real time by the tension detection unit and the preset constant tension target value, so that the tension of all mooring lines is maintained within the set test tension range in real time. Test process monitoring and recording steps: Real-time monitoring and recording of the working status of each shipborne anchor winch and the cable tension data collected by the tension detection unit; Test completion and judgment steps: After the test has lasted for at least one complete tidal unidirectional change process, the test is judged as qualified based on the monitoring and recording data in the test process monitoring and recording steps.

[0010] As a preferred embodiment, in the mooring and parameter setting steps, the mooring cable is in a slack state when it is fixed to the corresponding dock bollard.

[0011] As a preferred embodiment, in the synchronous start-up test step, the start command controls all shipborne anchor winches to start working from a preset non-zero starting position, which corresponds to the lower limit of the test tension range.

[0012] As a preferred embodiment, in the adaptive constant tension control step, when the tension of the mooring cable reaches the upper limit of the test tension range, equally spaced physical travel marks are made on the mooring cable.

[0013] As a preferred embodiment, the spacing of the physical travel markers is set at 500mm.

[0014] As a preferred embodiment, in the cable setting and parameter setting steps, the test tension range is set to 25% to 75% of the safe working load of the mooring cable.

[0015] Compared with existing technologies, the present invention provides a constant tension mooring device and testing method for ship anchor winches. The advantages are as follows: multiple shipboard anchor winches are distributed in the bow and stern areas, creating a symmetrical force distribution pattern for the mooring lines at both ends of the ship, laying the physical foundation for symmetrical force distribution; each anchor winch body is fixed to the deck, and the mooring line is wound around the anchor winch body; the drive device is connected to the anchor winch body, forming the actuator for releasing and winding the mooring line; the tension detection unit and stroke detection unit respectively collect the tension data, winding / unwinding length, and speed data of each mooring line in real time, providing sensory data information for automatic tensioning synchronization control; the shipboard bollards include bow bollards and stern bollards. The system is symmetrically arranged along the bow and stern of the vessel. On the one hand, it utilizes the hull area to bear the tension and protect the base of the ship's anchor winch. On the other hand, it provides guidance for the mooring lines leading from the corresponding ship's anchor winches, ensuring that the lines follow the correct direction and have consistent stress. Multiple dock bollards are fixed to the dock, and each bollard is fixed to the free end of the corresponding line after being guided by the bollard on the ship. This, together with the ship's system, forms a complete force loop, realistically simulating actual mooring conditions. The central controller is electrically connected to all drive devices, tension detection units, and stroke detection units. It centrally processes multi-source data and, based on the deviation between the preset constant tension target value and real-time feedback, calculates and synchronously sends control commands to achieve automatic tensioning and constant tension adjustment. The symmetrically arranged bollards on board ensure consistent stress changes in all mooring lines, creating a physical prerequisite for multi-machine collaboration. The central controller synchronously adjusts each drive device based on all feedback information, forming a closed-loop control circuit. This enables the mooring lines to coordinate their release and tension balance under tidal changes, enhancing their ability to resist lateral forces and ensuring the stability and reliability of the mooring lines under different tidal conditions. It also enables synchronous linkage testing of multiple shipborne anchor winches, improving the accuracy of constant tension control and increasing testing efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the bow cable structure according to an embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the stern cable structure according to an embodiment of the present invention.

[0018] In the picture: 10. Shipboard anchor winch; 11. Bow area; 12. Stern area; 13. Mooring lines; 14. Line sections; 20. Ship with bollards; 21. Port bow bollards; 22. Starboard bow bollards; 23. Center bow bollards; 24. Port stern bollards; 25. Starboard stern bollards; 26. Center stern bollards; 27. Dock bollards. X, the first direction. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0020] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0021] In the description of this invention, it should be understood that the terms "connected," "linked," and "fixed," etc., used in this invention should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or a welded connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly defined. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] like Figures 1 to 2 As shown, a preferred embodiment of the present invention provides a constant tension mooring device for a ship's anchor winch, comprising: Multiple shipborne anchor winches 10 are distributed in the bow area 11 and the stern area 12. Each shipborne anchor winch 10 includes an anchor winch body, a drive unit, and a mooring line 13. The mooring line 13 is wound around the anchor winch body. The drive unit is connected to the anchor winch body for transmission. The anchor winch body is used to fix the ship deck. Each shipborne anchor winch 10 is equipped with a tension detection unit for real-time acquisition of tension data of the corresponding mooring cable 13 and a stroke detection unit for real-time acquisition of the take-up and release length and speed data of the corresponding mooring cable 13. Shipboard bollards 20 are used to secure the ship's deck, including bow bollards and stern bollards; wherein the bow bollards and stern bollards are arranged symmetrically along the bow and stern direction of the ship; each shipboard bollard 20 is used to guide the mooring line 13 led out from the corresponding shipboard anchor winch 10 and to guide the mooring line 13 to the outside of the ship. Multiple dock bollards 27 are used to fix the mooring line 13 at a position after being guided by the bollard 20 on the ship. The central controller is electrically connected to all drive units, tension detection units, and stroke detection units. The central controller is configured to: receive real-time tidal data; generate and send synchronous control commands to all shipboard anchor winches 10 based on a preset constant tension target value and real-time tidal data; and receive and process tension data and length-in / out data to adjust the drive units using closed-loop feedback.

[0023] The constant tension mooring device for ship anchor winches of the present invention comprises multiple shipborne anchor winches 10 distributed in the bow region 11 and stern region 12, so that the mooring lines 13 form a symmetrical force distribution pattern at both ends of the ship, laying the physical basis for symmetrical force distribution at the bow and stern; each anchor winch body is fixed to the ship deck, and the mooring lines 13 are wound around the anchor winch body; the drive device is connected to the anchor winch body to form the actuator for raising and lowering the mooring lines 13; the tension detection unit and the stroke detection unit respectively collect the tension data and the raising and lowering length of each mooring line 13 in real time. Speed ​​data provides sensing data information for automatic tensioning synchronization control. The ship's bollards 20, including bow and stern bollards, are symmetrically arranged along the bow and stern of the ship. On one hand, they utilize the hull area to bear tension and protect the base of the ship's anchor winch 10; on the other hand, they provide guidance for the mooring lines 13 leading from the corresponding ship's anchor winch 10, ensuring that each line follows a standardized direction and has a consistent force trend. The symmetrical mooring lines 13 can generate restoring force components to counteract lateral displacement, forming a stable force triangle structure and improving the ship's resistance to roll and pitch. Multiple dock bollards 27 are fixed to the dock, each dock bollard 27 fixed to the free end of the corresponding line after being guided by the ship's bollards 20, thus forming a complete force loop with the ship's system, realistically simulating actual mooring conditions. The central controller is electrically connected to all drive devices, tension detection units, and stroke detection units, centrally processing multi-source data and calculating and synchronously sending control commands based on the deviation between the preset constant tension target value and real-time feedback, achieving automatic tensioning and constant tension adjustment. The symmetrically arranged bollards 20 on board ensure that the force changes of each mooring line 13 are consistent, creating a physical prerequisite for multi-machine collaboration. The central controller synchronously adjusts each drive device based on all feedback information, forming a closed-loop control circuit. This enables each mooring line 13 to coordinate its release and tension balance under tidal changes, improving its ability to resist lateral forces and ensuring the stability and reliability of the mooring lines 13 under different tidal conditions. It also enables synchronous linkage testing of multiple shipborne anchor winches 10, improving the control accuracy of constant tension and increasing test efficiency.

[0024] It should be noted that the ideal state of the 'symmetrical arrangement' in this invention is mathematical geometric symmetry, but it can also be understood as engineering symmetry. This means that the number, type, connection height, and function of the bow and stern mooring lines 13 are similar to form a balanced couple, emphasizing the symmetry of the force effect and ensuring that the ship does not experience excessive lateral movement or turning under the influence of wind, waves, currents, and tides. During the trial mooring, the root of each line is first fixed to the drum of the corresponding shipboard anchor winch 10. Then, the mooring lines 13 are led out and sequentially passed through the corresponding shipboard bollards 20 for anchoring or through the guide holes to change the direction of force. Finally, the free ends of the mooring lines 13 are led to the dock and securely fastened to the pre-selected dock bollards 27, so that the fixed bow and stern mooring lines 13 are arranged symmetrically with respect to the ship's longitudinal axis. For example, after the mooring line 13, which bypasses the port bow bollard 21, is fixed to the dock bollard 27 corresponding to the port bow position, a port side mooring line segment 14 is formed; after the mooring line 13, which bypasses the port stern bollard 24, is fixed to the dock bollard 27 corresponding to the port stern position, a port side mooring line segment 14 is formed. This port side mooring line segment 14 and the port side mooring line segment 14 are located at the bow and stern of the ship, respectively, and are arranged symmetrically with respect to the ship's longitudinal axis. This creates a symmetrical force distribution pattern at both ends of the ship, jointly resisting the pitching and heaving motions caused by tidal changes.

[0025] During the test, the launching and retracting actions of the shipborne anchor winch 10 adjusted the overall tension of the entire cable by changing the reserved length of the cable on the ship, thereby achieving constant tension control.

[0026] As one embodiment, for a shipborne anchor winch 10 with a rated power of 5kW, the mooring cable 13 is a 12.5mm² steel wire rope, and a span range of 25%-75% is selected.

[0027] As one example, the safe working load of the dock bollard 27 is not less than 35 tons.

[0028] As one embodiment, the effectiveness of testing is achieved by utilizing the ship's own new mooring lines 13, since each ship owner has a suitable and sufficient number of new mooring lines 13; by combining the time of mooring the new lines onto the ship with the synchronous testing, approximately 200,000 in line costs and time can be saved, as well as ensuring the safety of the mooring lines 13.

[0029] Furthermore, such as Figures 1 to 2As shown, the mooring line 13 between the ship's bollard 20 and the dock bollard 27 forms a line segment 14. The line segment 14 forms an angle α with the ship's longitudinal axis, with the angle α ranging from 45° to 60°. The symmetrical line segment 14 generates a restoring force component to counteract lateral displacement, forming a stable triangular force structure and improving the ship's resistance to roll and pitch. The direction of extension of the ship's longitudinal axis is the first direction X.

[0030] Furthermore, such as Figures 1 to 2 As shown, multiple dock bollards 27 are arranged at intervals, with a spacing of 3m-8m between adjacent dock bollards 27. The multiple dock bollards 27 are arranged at intervals along the length of the ship when it is docked at the dock, which ensures that the mooring lines 13 do not interfere with each other or rub against each other during the release and retrieval process, and makes the elastic deformation range of each mooring line 13 tend to be consistent, providing a uniform controlled object, while ensuring that the test covers all mooring points of the ship.

[0031] As one embodiment, such as Figures 1 to 2 As shown, the interval between adjacent dock bollards 27 is 5m.

[0032] Furthermore, such as Figures 1 to 2 As shown, the bow bollards include port bow bollard 21, starboard bow bollard 22, and bow center bollard 23; the stern bollards include port stern bollard 24, starboard stern bollard 25, and stern center bollard 26. These are all areas of reinforced hull structure and are the standard points of application for mooring forces. The cable connection points are located symmetrically at the bow and stern, simultaneously constraining the ship's pitch, heave, and yaw movements, forming a multi-dimensional stabilizing moment and ensuring consistent tension changes in all cables during tidal variations.

[0033] As one embodiment, such as Figures 1 to 2 As shown, the number of shipborne anchor winches 10 is even to achieve effective force symmetry.

[0034] As one embodiment, such as Figures 1 to 2 As shown, there are 6 shipboard anchor winches 10, and the mooring lines 13 are respectively connected to the port bow bollard 21, the starboard bow bollard 22, the bow center bollard 23, the port stern bollard 24, the starboard stern bollard 25, and the stern center bollard 26.

[0035] A test method for a constant tension mooring device for ship anchor winches, such as Figures 1 to 2 As shown, the test conducted using a ship's anchor winch constant tension mooring device includes the following steps: Test preparation steps: Collect the no-load parameters of each shipborne anchor winch 10 and check whether the working status of the drive device, tension detection unit, and stroke detection unit is normal. By collecting the no-load parameters of each shipborne anchor winch 10 and checking the working status of the drive device, tension detection unit, and stroke detection unit, an accurate initial benchmark is established for subsequent tests, ensuring that all execution and sensing components are in normal condition. This eliminates test errors caused by uncertain equipment status and solves the problems of low control accuracy and difficult fault diagnosis caused by the lack of system calibration in traditional tests. It should be noted that the no-load parameters include, but are not limited to, the motor no-load current and voltage; the inverter zero-speed output torque; the encoder zero-position calibration value; the tension sensor zero point; and the initial winding state of the drum. This provides a data basis for fault diagnosis and test reproduction, and is used for system calibration and fault diagnosis.

[0036] As one embodiment, the test period is determined by selecting a time period with a tidal difference greater than 100cm. Preferably, the tidal difference is ensured to be within the range of 100-150cm.

[0037] Furthermore, in the test preparation steps, the tide table parameters, i.e., the real-time data of the local tide forecast, are monitored according to the test requirements. Meanwhile, the frequency converter is the core speed control device for the motor of the shipborne anchor winch 10; the encoder is usually installed on the drum shaft or motor shaft of the shipborne anchor winch 10 to measure the length and speed of the mooring cable 13, and to confirm whether the frequency converter and encoder are functioning normally.

[0038] The mooring and parameter setting steps involve, based on on-site tidal forecast data, winding one end of the mooring line 13 around the shipborne anchor winch 10, and then guiding the other end sequentially through the ship's mooring bollards 20 to the corresponding dock bollards 27, ensuring that the fixed mooring lines 13 are symmetrically arranged relative to the ship's longitudinal axis; simultaneously, a test tension range is set. By performing the mooring operation based on on-site tidal forecast data, ensuring that the fixed mooring lines 13 are symmetrically arranged relative to the ship's longitudinal axis, and setting a test tension range, a symmetrical force system with bow and stern coordination is constructed from a physical perspective. This lays the mechanical foundation for subsequent multi-machine collaborative control and solves the problems of poor lateral force resistance and inability to realistically simulate actual mooring conditions caused by arbitrary line routing and uneven force distribution in traditional tests.

[0039] Synchronous start-up test procedure: The central controller simultaneously sends start commands to the drive devices of all shipborne anchor winches 10, enabling the shipborne anchor winches 10 to operate. This achieves the synchronous start-up of multiple shipborne anchor winches 10, eliminating the time difference and asynchronous force caused by traditional batch start-up. It creates a unified starting point for subsequent coordinated adjustment and solves the problem of inconsistent initial force and difficulty in achieving multi-machine linkage caused by asynchronous start-up in traditional tests.

[0040] Adaptive Constant Tension Control Steps: During tidal changes, the central controller adjusts the drive devices of each shipborne anchor winch 10 based on the deviation between the tension data of each mooring line 13 collected in real time by the tension detection unit and the preset constant tension target value. This ensures that the tension of all mooring lines 13 is maintained within the set test tension range in real time. This step forms a closed-loop control circuit of perception, decision-making, and execution, realizing dynamic tracking and automatic adjustment of tidal changes. It solves the problems of low control accuracy and high risk of line breakage caused by manual adjustment lag and independent tension control in traditional tests. The central controller synchronously commands the operation with the goal of maintaining constant tension in each mooring line 13. Ideally, the positions of each shipborne anchor winch 10 should be similar. However, due to individual differences in equipment and slight variations in the state of the mooring lines 13, slight instantaneous deviations in position are permissible. The control objective of the central controller is to ensure that the real-time deviation of the tension value of each mooring line 13 does not exceed ±5% of the set value, thereby ensuring dynamic balance of overall force.

[0041] The test process monitoring and recording steps are as follows: Real-time monitoring and recording of the working status of each shipborne anchor winch 10, the cable tension data collected by the tension detection unit, and, depending on the needs, the collection of the release and take-up travel data and tidal data collected by the travel detection unit; real-time monitoring and recording of the working status of each anchor winch, tension data, release and take-up travel data of the mooring cable 13, and tidal data, providing a complete data traceability and status awareness means for the test process, and solving the problems of difficult fault diagnosis and inability to reproduce test results caused by data loss in traditional tests.

[0042] Test completion and judgment steps: After the test has lasted for at least one complete tidal unidirectional change process, the test qualification is judged based on the monitoring and recording data in the test process monitoring and recording steps; after the test has lasted for at least one complete tidal unidirectional change process, the test qualification is judged based on the monitoring and recording data, ensuring that the test fully covers the entire process of tidal change, assesses the long-term stability and dynamic following capability of the system in a real environment, and whether the device can maintain the tension of each mooring cable 13 within the set range for a long time, stably and collaboratively under the simulated real service environment, i.e. tidal change, thereby evaluating whether the overall functionality, reliability and safety of the shipborne constant tension mooring system meet the delivery standards.

[0043] In one embodiment, during the test completion and judgment steps, the pass / fail standard is that throughout the entire test, the load value of all mooring lines 13 does not exceed ±5% of the set value, the ship's anchor winch constant tension mooring device operates stably, no fault alarms causing shutdown are triggered, and the mooring line 13 retraction and deployment movements are smooth and consistent with tidal change logic. If the test fails, the system will automatically execute preset safety procedures, such as stopping the operation or maintaining the current tension. Subsequently, based on the fault data and alarm information recorded by the control system, specific equipment, such as sensors, mechanical components, or control logic problems, are investigated. After repair, the test must be repeated or resumed from the point of interruption.

[0044] It should be noted that the 'set value' in this invention refers to the instantaneous target tension value dynamically calculated by the central controller based on real-time tidal data and a preset constant tension model. This value continuously changes within the test tension range as the tides change. The ±5% in the test qualification standard refers to the allowable fluctuation range of the actual tension around this dynamic target value, rather than around a fixed gear threshold. The load value of mooring cable 13 in the table belongs to the system safety protection boundary, and the two together constitute a complete control strategy.

[0045] Furthermore, the test duration was set at 6 hours. Most ports in my country experience semi-diurnal tides with a cycle of approximately 12 hours. A 6-hour test covers a complete half-cycle of high or low tide, sufficient to assess the dynamic following and long-term stability of the constant tension system under continuous unidirectional tidal changes. The essential requirement of this invention is that the test should last for at least one complete and significant tidal change process.

[0046] Furthermore, during the mooring and parameter setting steps, the mooring lines 13 are in a slack state when fixed to the corresponding dock bollards 27. Before the formal start of the test, the slack state of the mooring lines 13 is manually maintained to establish a unified, strain-free reference starting point for subsequent synchronous start-up and automatic tension control. If the mooring lines 13 are already in a pre-tensioned state when fixed, each mooring line 13 will have different degrees of initial tension due to factors such as the mooring path and differences in manual operation. This would result in uneven force on each mooring line 13 at the start of the test, making it impossible for the central controller to accurately determine which tension changes are caused by the tide and which are caused by the initial pre-tension, thus interfering with the accuracy and response speed of the control algorithm. Maintaining a slack state ensures that all mooring lines 13 are in the same zero-stress state before the start of the test, ensuring that each mooring line 13 can enter the tensioning process simultaneously during subsequent synchronous start-up. Tension changes are entirely determined by the unified command of the central controller and tidal changes, creating clean initial conditions for achieving high-precision constant tension control.

[0047] Furthermore, in the synchronous start-up test step, the start command controls all shipborne anchor winches 10 to begin operation from a preset non-zero starting position, which corresponds to the lower limit of the test tension range. This eliminates system gaps and establishes a stable benchmark. The transmission system of the shipborne anchor winches 10 has mechanical gaps, and the cables themselves have a certain degree of sag. Starting from a non-zero tension starting point allows all mooring lines 13 to quickly enter a uniformly tensioned state, establishing a stable and comparable initial platform for subsequent synchronous adjustments. On the other hand, it avoids zero-point drift interference, as the tension detection unit has a relatively large error when close to zero. Starting from a non-zero starting position ensures clear and reliable measurement signals, improving the control accuracy of the entire test process.

[0048] Furthermore, in the adaptive constant tension control step, when the tension of mooring cable 13 reaches the upper limit of the test tension range, equally spaced physical travel marks are made on mooring cable 13. These equally spaced physical travel marks are primarily used for visual monitoring and recording. By making a clear mark at equal intervals on mooring cable 13, such as by painting color rings or binding color codes to the cable, operators can intuitively and quickly visually determine whether the cable retraction and extension are coordinated; assess whether the retraction and extension travel matches the tidal change trend; and provide a traceable physical travel status in addition to system recording. Determining whether the retraction and extension of each cable is active and within the expected travel range is an efficient and reliable manual verification method to assist PLC electronic detection. The core is to form a travel reference that can be observed and recorded.

[0049] Furthermore, the spacing of the physical travel markers is set at 500mm. This 500mm spacing allows operators to clearly identify changes in marker position within an observation distance of several meters to over ten meters, which is sufficient to precisely record the dynamic evolution of the cable's release and retraction travel. This achieves a dual-track verification mechanism of electronic detection and manual visual inspection, improving the controllability of the test process and the reliability of the results.

[0050] Furthermore, in the cable setting and parameter configuration steps, the test tension range is set to 25% to 75% of the safe working load of the mooring cable 13. This is an optimal engineering value that balances safety, adequacy, and efficiency, and its determination is based on the following formulas and principles: Test tension = (minimum breaking load of cable / safety factor) × K Safety factor: usually 4-6 (based on classification society rules and operation manuals).

[0051] K: is the test load factor, set to 0.25 to 0.75.

[0052] For example, if the breaking load of a cable is 100t and the safety factor is 4, then the safe working load (SWL) is 25t. During the test, in order to verify the performance of the system across the entire working range and to reserve a safety margin, the test range is selected from 25%*SWL (6.25t) to 75%*SWL (18.75t), corresponding to the 25%-75% range of the control system.

[0053] The value of the cable load is calculated based on the operating gear. The central controller uses the data obtained by the tension detection unit to control the drive device to automatically retract and extend the mooring cable 13.

[0054] As one embodiment, the automatic tensioning parameters are set as shown in the table below: Initially, the central controller is set to the 25% setting. When the tension detection unit detects a load of ≤18KN on the mooring line 13, the central controller controls the drive unit to reel in the line; when the tension detection unit detects a load of ≥56KN on the mooring line 13, the central controller controls the drive unit to release the line; when the tension detection unit detects a load of 18KN-56KN on the mooring line 13, the central controller controls the drive unit to remain inactive. The control logic is the same for the other settings. This control logic setting can prevent frequent start-stop of the shipborne anchor winch 10 due to small tidal fluctuations, protecting the mechanical equipment and control system. If the tension detection unit obtains data within the overlapping range of adjacent gears for the load of the mooring cable 13, such as when the load value of the mooring cable 13 is 55KN, the central controller first confirms the current working gear. If it is currently at the 25% gear, it determines to remain inactive. However, if the load value of the mooring cable 13 continues to rise and exceeds 56KN, the central controller will first perform the rope release action within that gear. If the load value of the mooring cable 13 obtained by the tension detection unit within the set number of data acquisitions after rope release still cannot fall back, or if the tide continues to rise and the tension pressure increases, the controller will gradually increase the gear, such as switching to the 50% gear, to increase the rope release capacity. If the current position is 50%, a rope-reeling action is initiated, but the position remains at 50%. However, if the load on mooring cable 13 continues to decrease and falls below 55 kN, the central controller will first perform a rope-reeling action within this position. If the load on mooring cable 13 still cannot recover after rope reeling, or if the tide continues to recede, the central controller will gradually reduce the position, such as switching to the 25% position, to ensure a smooth transition of the system during tidal changes, avoid tension shocks caused by sudden changes in the position, and achieve high-precision constant tension control.

[0055] The correspondence between the gear position and the load of the mooring cable 13 is obtained through the factory calibration curve of the shipborne anchor winch 10. The manufacturer tests the output tension at different gear positions (or current / frequency values) to form a gear position and tension correspondence table, which is pre-loaded into the control database of the central controller for control and monitoring.

[0056] In summary, this invention provides a constant tension mooring device and testing method for ship anchor winches. Multiple shipboard anchor winches 10 are distributed in the bow region 11 and stern region 12, creating a symmetrical force distribution pattern for the mooring lines 13 at both ends of the ship, laying the physical foundation for symmetrical force distribution. Each anchor winch body is fixed to the ship's deck, and the mooring line 13 is wound around the anchor winch body. A drive device is connected to the anchor winch body, forming the actuator for raising and lowering the mooring line 13. Tension detection units and stroke detection units respectively collect the tension of each mooring line 13 in real time. Data on the length and speed of the mooring and retrieval operations provide sensory information for automatic tensioning synchronization control. The ship's bollards 20, including bow and stern bollards, are symmetrically arranged along the bow and stern of the ship. On one hand, they utilize the hull area to bear the tension and protect the base of the ship's anchor winch 10; on the other hand, they provide guidance for the mooring lines 13 extending from the corresponding ship's anchor winch 10, ensuring that each line follows a standardized direction and has a consistent force trend. The symmetrical mooring lines 13 generate restoring force components to counteract lateral displacement, forming a stable force triangle structure and improving the ship's resistance to roll and pitch. Multiple dock bollards 27 are fixed to the dock, each dock bollard 27 fixed to the free end of the corresponding line after being guided by the ship's bollards 20, thus forming a complete force loop with the ship's system, realistically simulating actual mooring conditions. The central controller is electrically connected to all drive devices, tension detection units, and stroke detection units, centrally processing multi-source data and calculating and synchronously sending control commands based on the deviation between the preset constant tension target value and real-time feedback, achieving automatic tensioning and constant tension adjustment. The symmetrically arranged bollards 20 on board ensure that the force changes of each mooring line 13 are consistent, creating a physical prerequisite for multi-machine collaboration. The central controller synchronously adjusts each drive device based on all feedback information, forming a closed-loop control circuit. This enables each mooring line 13 to coordinate its release and tension balance under tidal changes, improving its ability to resist lateral forces and ensuring the stability and reliability of the mooring lines 13 under different tidal conditions. It also enables synchronous linkage testing of multiple shipborne anchor winches 10, improving the control accuracy of constant tension and increasing test efficiency.

[0057] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several improvements and substitutions without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A constant tension mooring device for ship anchor winches, characterized in that, include: Multiple shipborne anchor winches are distributed in the bow and stern areas of the ship. Each shipborne anchor winch includes a mooring line, a drive unit, and an anchor winch body for fixing to the ship's deck. The mooring line is wound around the anchor winch body, and the drive unit is connected to the anchor winch body for transmission. Each of the shipborne anchor winches is equipped with a tension detection unit for real-time acquisition of tension data of the corresponding mooring line and a stroke detection unit for real-time acquisition of the take-up and release length and speed data of the corresponding mooring line. Shipboard bollards are used to secure the ship to its deck, including bow bollards and stern bollards; wherein the bow bollards and the stern bollards are arranged symmetrically along the bow and stern direction of the ship. Multiple dock bollards are used to secure the ship to the dock, and each of the dock bollards is used to secure the free end of a mooring line at a position corresponding to a position after being guided by the bollard on the ship. The central controller is electrically connected to all the drive devices, the tension detection unit, and the stroke detection unit.

2. The constant tension mooring device for ship anchor winches according to claim 1, characterized in that: The mooring line between the ship's bollard and the dock bollard forms a line segment, and the line segment forms an angle α with the ship's longitudinal axis, the angle α being set between 45° and 60°.

3. The constant tension mooring device for ship anchor winches according to claim 1, characterized in that: The multiple wharf bollards are arranged at intervals, with the interval between adjacent wharf bollards being 3m-8m.

4. The constant tension mooring device for ship anchor winches according to claim 1, characterized in that: The bow bollards include port bow bollards, starboard bow bollards, and bow center bollards; the stern bollards include port stern bollards, starboard stern bollards, and stern center bollards.

5. A test method for a ship anchor winch constant tension mooring device, wherein the ship anchor winch constant tension mooring device according to any one of claims 1-4 is used for testing, characterized in that: Includes the following steps: Mooring and parameter setting steps: Wind one end of the mooring line around the ship's anchor winch body, and then guide the other end through the ship's mooring bollards and fix it to the corresponding dock bollards in sequence, so that the fixed mooring lines are arranged in an engineering symmetrical manner relative to the ship's longitudinal axis, and at the same time set the test tension range. Synchronous start-up test procedure: The central controller simultaneously sends a start command to the drive device of all shipborne anchor winches to make the shipborne anchor winches work. Adaptive constant tension control steps: During tidal changes, the central controller adjusts the drive devices of each shipborne anchor winch according to the deviation between the tension data of each mooring line collected in real time by the tension detection unit and the preset constant tension target value, so that the tension of all mooring lines is maintained within the set test tension range in real time. Test process monitoring and recording steps: Real-time monitoring and recording of the working status of each shipborne anchor winch and the cable tension data collected by the tension detection unit; Test completion and judgment steps: After the test has lasted for at least one complete tidal unidirectional change process, the test is judged as qualified based on the monitoring and recording data in the test process monitoring and recording steps.

6. The test method for the constant tension mooring device of the ship's anchor winch according to claim 5, characterized in that: During the mooring and parameter setting steps, the mooring cable is in a slack state when it is fixed to the corresponding dock bollard.

7. The test method for the constant tension mooring device of the ship's anchor winch according to claim 5, characterized in that: In the synchronous start-up test step, the start command controls all shipborne anchor winches to start working from a preset non-zero starting position, which corresponds to the lower limit of the test tension range.

8. The test method for the constant tension mooring device of the ship's anchor winch according to claim 5, characterized in that: In the adaptive constant tension control step, when the tension of the mooring cable reaches the upper limit of the test tension range, equally spaced physical travel marks are made on the mooring cable.

9. The test method for the constant tension mooring device of the ship's anchor winch according to claim 8, characterized in that: The spacing of the physical travel markers is set at 500mm.

10. The test method for the constant tension mooring device of the ship's anchor winch according to claim 5, characterized in that: In the mooring and parameter setting steps, the test tension range is set to 25% to 75% of the safe working load of the mooring cable.

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