A method for joint debugging and re-winding of a super-large oil cylinder of a marine engineering vessel pile frame

Abstract

This invention relates to the field of piling drive technology for marine engineering vessels, and particularly to a method for joint commissioning and changing the winch of an ultra-large hydraulic cylinder on a marine engineering vessel piling system. The specific steps are as follows: Step 1: Safety test of the auxiliary hydraulic cylinder system, including structural strength safety test and hydraulic cylinder reset test; Step 2: Safety test of the main hydraulic cylinder system; Step 3: Joint commissioning of the ultra-large hydraulic cylinder; Step 4: Winch replacement operation of the main hydraulic cylinder, including preparation before replacement, slideway switching, and centering pin. This method has been verified through practical application. The safety test coverage is comprehensive, the pressure during joint commissioning is stable, and the winch replacement operation is efficient and smooth. It fully meets the safety and reliability requirements of piling operations on marine engineering vessels, adapts to the special working conditions of piling systems on marine engineering vessels, and is convenient, safe, and reliable to operate. It fills the gap in the industry for joint commissioning and changing the winch of ultra-large hydraulic cylinders on ultra-large vessels and can be widely applied to the piling commissioning operations of similar large vessels, possessing significant practical value and promotional significance.

Description

Technical Field

[0001] This invention relates to the field of marine engineering vessel pile driver technology, and in particular to a method for adjusting and replacing the winch of an ultra-large hydraulic cylinder in a marine engineering vessel pile driver. Background Technology

[0002] In the fields of marine engineering and bridge construction, marine engineering vessels are core equipment. The pile frame on the vessel is a key load-bearing and operating structure. The stability and safety of its lifting and erecting operations directly determine the success or failure of the entire pile driving operation.

[0003] Currently, the industry's safety testing and joint commissioning technology for ultra-large hydraulic cylinders on ultra-large ship pile frames is still imperfect, with many technical pain points: First, there is a lack of systematic solutions for verifying the structural safety and reliability during commissioning, and key indicators such as the strength and sealing of the ultra-large hydraulic cylinder body and connecting system cannot be fully and accurately tested, resulting in incomplete safety testing; Second, the pressure is prone to imbalance when the ultra-large hydraulic cylinders are linked, and excessively low pressure in a single cylinder can easily lead to overpressure in other cylinders, or even trigger the safety valve threshold, causing safety accidents; Third, it is difficult to accurately set the critical point for individual operation of ultra-large hydraulic cylinders, which can easily lead to excessively high pressure or repeated adjustments; Fourth, jamming and scraping are prone to occur during the replacement of the main hydraulic cylinder, and the alignment of the joint bearings is difficult, resulting in low work efficiency and safety hazards. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for the joint commissioning and replacement of the super-large hydraulic cylinder of the pile frame of marine engineering vessels that is structurally reasonable, easy to operate, safe and reliable, and can combine the comprehensiveness of safety testing, the stability of the joint commissioning process and the high efficiency of the winch replacement operation.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: a method for joint adjustment and replacement of the oversized hydraulic cylinder of a marine engineering vessel pile frame, the innovation of which lies in: including a main hydraulic cylinder system, an auxiliary hydraulic cylinder system, a pressure monitoring module, a centering auxiliary module, and a control module. The specific steps of the joint adjustment and replacement of the oversized hydraulic cylinder are as follows: Step 1: Safety test of the auxiliary cylinder system, including structural strength safety test and cylinder reset test, during which the main cylinder system is locked; The structural strength safety test is as follows: the first-stage cylinder of the auxiliary oil cylinder is extended, the piston rod insert supports the pile frame pin, and the pressure is gradually increased to 5MPa and checked; after confirming that there is no abnormality, the pressure is increased by 5MPa and checked once, until the pressure is increased to 22MPa. After confirming that the pressure is consistent, the hydraulic pump is shut off and a 1-hour pressure holding test is carried out. Step 2: Safety test of the main hydraulic cylinder system. A graded loading method is adopted. After each stage of loading is completed, the system is unloaded and the stress on the main components is checked. The first stage is pressurized to 5MPa, and after holding the pressure for 10 minutes, the contact surface matching is checked. The second stage is pressurized to 15MPa, and the connection parts are checked. The third stage is pressurized to 22.5MPa, and the pressure test is repeated. Step 3: Joint adjustment of the ultra-large hydraulic cylinder, including setting the working pressure of the three cylinders and setting the critical point for individual operation of the main hydraulic cylinder; Step 4: Main cylinder winch replacement operation, including preparation before winch replacement, slide rail switching and centering pin installation. First, check and correct the dimensions of the winch replacement slide rail; then control the main cylinder to slide along the slide rail to the rear support leg; finally, use the centering auxiliary module to achieve self-alignment and centering of the main cylinder and complete the pin installation.

[0006] Furthermore, the main hydraulic cylinder system includes a main hydraulic cylinder body, a front support for the winch replacement, a rear support leg, and a winch replacement slide. The main hydraulic cylinder body is located inside the pile frame truss. The bottom end of the main hydraulic cylinder body is connected to the hull base, and the top end is a piston rod. The piston rod end is provided with an ear structure with a joint bearing. The joint bearing cooperates with the pin on the front support for the winch replacement or the rear support leg to form a swingable mechanical connection. The winch replacement slide is located inside the truss and between the front support for the winch replacement and the rear support leg, and is used for guiding the switching of the main hydraulic cylinder hinge point. The auxiliary cylinder system includes an auxiliary cylinder body, a swing cylinder, and a return solenoid valve. The auxiliary cylinder body is a three-stage telescopic plunger cylinder. The auxiliary cylinder body is hingedly installed in the main hull near the middle of the hull. Its piston rod head is embedded in the load-bearing pin of the pile frame with a plug structure to support the load-bearing pin of the pile frame. The swing cylinder is connected to the auxiliary cylinder body and is used to drive the auxiliary cylinder body to vertically reset. The return solenoid valve is set in the return oil pipeline of the auxiliary cylinder body and is used to control the piston rod to fall back. The pressure monitoring module includes multiple pressure sensors, which are respectively installed on the oil inlet and return lines of the main cylinder body, the oil inlet and return lines of the auxiliary cylinder body, and the control panel, to monitor the local pressure of multiple cylinders and the pressure on the control panel in real time, ensuring that the pressure data is synchronized. The centering auxiliary module includes a spherical bearing adjusting ring and a pin centering adjusting block. The spherical bearing adjusting ring is fitted onto the outside of the spherical bearing at the end of the piston rod of the main cylinder. It is designed according to the maximum swing angle of the spherical bearing to limit the excessive deflection angle of the spherical bearing during the centering process. The pin centering adjusting block is installed on the pin bushing of the rear support leg, and its outer circle matches the pin bushing, while its inner circle matches the pin and the cylinder trunnion. It is used to achieve self-aligning centering of the main cylinder. The control module is electrically connected to the main cylinder system, the auxiliary cylinder system, and the pressure monitoring module, respectively, and is used to control the pressure loading, cylinder extension and retraction, and state switching during safety tests, joint commissioning, and winch replacement processes.

[0007] Furthermore, the switching slide has undergone dynamic simulation optimization design to avoid structural interference risks. The surface of the switching slide has been modified and polished to a roughness of ≤Ra3.2μm, ensuring smooth switching of the main cylinder hinge point.

[0008] Furthermore, the pressure sensor has a measurement accuracy of no less than ±0.1MPa and a measurement range of 0-40MPa, and can provide real-time feedback on pressure changes, facilitating timely adjustment of the pressure loading rate by the control module.

[0009] Furthermore, the spherical bearing adjusting ring is clearance-fitted with the spherical bearing, with a clearance of 0.3-0.5mm, and a limiting structure is designed based on the maximum swing angle of 3° of the spherical bearing; and the outer circle of the pin centering adjusting block is interference-fitted with the pin sleeve, while the inner circle of the pin centering adjusting block is clearance-fitted with the pin and the cylinder trunnion, with a clearance of 0.2-0.3mm.

[0010] Furthermore, in step two, the specific process of hierarchical loading is as follows: S2.1 First stage loading: The main cylinder valve group is operated through the control module to gradually increase the pressure of the main cylinder to 5MPa and hold the pressure for 10 minutes; after the pressure holding is completed, the main cylinder is retracted and the contact position and contact surface matching between the main cylinder and the support before the winch replacement are checked. Only after confirming that the matching is good can the next stage loading be carried out. S2.2 Second stage loading: Operate the main cylinder valve group to load the main cylinder pressure to 15MPa. At this time, the main cylinder provides a thrust of about 17000kN. Check the connection between the front support of the pile frame and the main cylinder pin plate. After confirming that there are no abnormalities, continue loading. S2.3 Third stage loading: Gradually and slowly load the main hydraulic cylinder to the rated working pressure of 22.5MPa, check the shape of the main hydraulic cylinder connecting hose, stop operating the valve group and conduct a pressure holding test; after the pressure holding test is completed, repeat the inspection of the key parts of the first and second stage loading to confirm that all components are working normally.

[0011] Furthermore, step three specifically involves: S3.1 Three-cylinder working pressure setting: Before joint commissioning and startup, the pressure of the three cylinders is controlled by the control module to increase synchronously and slowly until the pressure reaches 16MPa, at which point the pile frame is lifted and detached from the support. At this point, the three-cylinder linkage operation is stopped. If the pressure drop of the auxiliary cylinder is significant, the pressure of the auxiliary cylinder is replenished separately to ensure that the operating status of the super-large cylinder system is consistent. Before the auxiliary cylinder is close to the extension of the secondary cylinder, the pressure of the main cylinder is replenished so that the pressure of the auxiliary cylinder drops below 12MPa, and the pressure of the main cylinder is maintained at around 16MPa, thus completing the pressure setting. S3.2 Setting the critical point for independent operation of the main cylinder: With the main cylinder and auxiliary cylinder fully extended, the main cylinder is operated to retract via the control module. The pressure of the main cylinder is monitored in real time. When the pressure rises to 18MPa, the retraction stops, which is 80% of the rated pressure. This position is recorded as the critical point and the system is calibrated. After calibration, the pressure of the main cylinder is ≤18MPa and the pressure of the auxiliary cylinder is 0 in the critical point state, realizing a safe switch from three-cylinder operation to single main cylinder operation.

[0012] By adopting a reverse search method to set the critical point for individual operation of the main cylinder, and calibrating the critical point at 80% of the rated pressure of the main cylinder, the problems of excessive pressure and repeated adjustments are avoided, thus ensuring the safety of single-cylinder operation.

[0013] Furthermore, step four specifically involves: 4.1 Preparations before changing the winch: Check and correct the dimensions of the winch replacement slide, and grind it. Pay special attention to checking the dimensions of the slide at the rear support foot to ensure there is no structural interference. 4.2 Slide Switching: The main cylinder piston rod is retracted by the control module, so that the main cylinder is disengaged from the front support of the winch change and slides along the winch change slide to the rear support position. During the process, the pressure monitoring module monitors the pressure change in real time to avoid jamming or scraping. 4.3 Alignment Pin: After the main hydraulic cylinder reaches the rear support position, the joint bearing adjustment ring is used to limit the joint bearing deflection angle. The main hydraulic cylinder trunnion is self-aligned by the pin alignment adjustment block. After the pin insertion alignment accuracy is achieved, the pin installation is completed and the trunnion replacement operation is finished.

[0014] The advantages of this invention are: 1. This method has been verified through practical application, with comprehensive safety testing coverage, stable pressure during the commissioning process, and efficient and smooth winch replacement operation. It fully meets the safety and reliability requirements of pile driver operations on marine engineering vessels, is adapted to the special working conditions of pile drivers on marine engineering vessels, and is convenient, safe, and reliable to operate. It fills the gap in the industry for the commissioning and replacement technology of ultra-large hydraulic cylinders on ultra-large vessels, and can be widely applied to the pile driver commissioning operations of similar large vessels. It has significant practical value and promotion significance.

[0015] 2. This method, through the design of a targeted safety test procedure, conducts graded loading strength tests and reset tests on the ultra-large hydraulic cylinder system, and combines a pressure monitoring module to achieve real-time synchronization of pressure data, comprehensively verifying the structural strength, sealing performance and reliability of the hydraulic cylinder body and system, and solving the technical problem of incomplete structural safety verification during the commissioning process.

[0016] 3. The three-cylinder working pressure setting scheme proposed in this method effectively avoids the pressure imbalance problem during three-cylinder linkage through the process of "synchronous pressure building-slow operation and observation-time pressure replenishment-pre-depressurization", prevents the safety risk of cylinder overpressure triggering, and improves the stability of the joint debugging process.

[0017] 4. The alignment auxiliary module composed of the joint bearing adjusting ring and the pin alignment adjusting block designed in this method, together with the optimized winch replacement slide, effectively solves the problems of jamming, scraping and high alignment difficulty in the main cylinder winch replacement process, reduces the safety risks of operators and improves the efficiency of winch replacement operation. Detailed Implementation

[0018] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with preferred embodiments, is provided below.

[0019] A method for joint adjustment and change of the oversized hydraulic cylinder of a marine engineering vessel pile frame includes a main hydraulic cylinder system, an auxiliary hydraulic cylinder system, a pressure monitoring module, a centering auxiliary module, and a control module.

[0020] The main hydraulic cylinder system includes the main hydraulic cylinder body, the front support for the winch replacement, the rear support leg, and the winch replacement slide. The main hydraulic cylinder body is located inside the pile frame truss. The front support for the winch replacement and the rear support leg are located on the front and rear sides of the pile frame truss, respectively. The bottom end of the main hydraulic cylinder body is connected to the hull base, and the top end is a piston rod. The piston rod end is equipped with an ear structure with a spherical bearing. The spherical bearing cooperates with the pin on the front support for the winch replacement or the rear support leg to form a swingable mechanical connection. The winch replacement slide is located inside the truss and between the front support for the winch replacement and the rear support leg. It is used for switching guidance of the main hydraulic cylinder hinge point. In this embodiment, the winch changing slide has been dynamically simulated and optimized to avoid structural interference risks. The surface of the winch changing slide has been modified and polished to a roughness of ≤Ra3.2μm, ensuring smooth switching of the main cylinder hinge point.

[0021] The auxiliary cylinder system includes an auxiliary cylinder body, a swing cylinder, and a return solenoid valve. The auxiliary cylinder body is a three-stage telescopic plunger cylinder. The auxiliary cylinder body is hinged and installed in the main hull near the middle of the hull. Its piston rod head is embedded in the load-bearing pin of the pile frame with a plug structure to support the load-bearing pin of the pile frame. The swing cylinder is connected to the auxiliary cylinder body and is used to drive the auxiliary cylinder body to vertically reset. The return solenoid valve is set in the return oil line of the auxiliary cylinder body and is used to control the piston rod to fall back. The pressure monitoring module includes multiple pressure sensors, which are installed on the oil inlet and return lines of the main cylinder body, the oil inlet and return lines of the auxiliary cylinder body, and the control panel, respectively, to monitor the local pressure of multiple cylinders and the pressure on the control panel in real time, ensuring that the pressure data is synchronized. In this embodiment, the pressure sensor has a measurement accuracy of no less than ±0.1MPa and a measurement range of 0-40MPa. It can provide real-time feedback on pressure changes, which facilitates the control module to adjust the pressure loading rate in a timely manner.

[0022] The centering auxiliary module includes a spherical bearing adjusting ring and a pin centering adjusting block. The spherical bearing adjusting ring is fitted onto the outside of the spherical bearing at the end of the piston rod of the main cylinder. It is designed according to the maximum swing angle of the spherical bearing and is used to limit the excessive deflection angle of the spherical bearing during the centering process. The pin centering adjusting block is installed on the pin bushing of the rear support leg. Its outer circle matches the pin bushing, and its inner circle matches the pin and the cylinder trunnion. It is used to achieve self-aligning centering of the main cylinder. In this embodiment, the spherical bearing adjusting ring is clearance-fitted with the spherical bearing, with a clearance of 0.3-0.5mm. A limiting structure is designed based on the maximum swing angle of 3° of the spherical bearing. Furthermore, the outer circle of the pin centering adjusting block is interference-fitted with the pin sleeve, and the inner circle of the pin centering adjusting block is clearance-fitted with the pin and the cylinder trunnion, with a clearance of 0.2-0.3mm.

[0023] The control module is electrically connected to the main cylinder system, the auxiliary cylinder system, and the pressure monitoring module, respectively, and is used to control the pressure loading, cylinder extension and retraction, and state switching during safety tests, joint commissioning, and winch replacement processes.

[0024] The specific steps for the joint adjustment and replacement of the oversized hydraulic cylinder are as follows: Step 1: Safety test of the auxiliary cylinder system, including structural strength safety test and cylinder reset test, during which the main cylinder system is locked; The structural strength safety test is as follows: the first-stage cylinder of the auxiliary oil cylinder is extended, the piston rod insert supports the pile frame pin, and the pressure is gradually increased to 5MPa and checked; after confirming that there is no abnormality, the pressure is increased by 5MPa and checked once, until the pressure is increased to 22MPa. After confirming that the pressure is consistent, the hydraulic pump is shut down and a 1-hour pressure holding test is carried out. The hydraulic cylinder reset test is performed by opening the auxiliary hydraulic cylinder pipeline ball valve and the return oil solenoid valve, and controlling the piston rod to return to its original position by self-resetting. Step 2: Safety test of the main hydraulic cylinder system. A graded loading method is adopted. After each stage of loading is completed, the system is unloaded and the stress on the main components is checked. The first stage is pressurized to 5MPa, and after holding the pressure for 10 minutes, the contact surface matching is checked. The second stage is pressurized to 15MPa, and the connection parts are checked. The third stage is pressurized to 22.5MPa, and the pressure test is repeated. The specific process of hierarchical loading is as follows: S2.1 First stage loading: The main cylinder valve group is operated through the control module to gradually increase the pressure of the main cylinder to 5MPa and hold the pressure for 10 minutes; after the pressure holding is completed, the main cylinder is retracted and the contact position and contact surface matching between the main cylinder and the support before the winch replacement are checked. Only after confirming that the matching is good can the next stage loading be carried out. S2.2 Second stage loading: Operate the main cylinder valve group to load the main cylinder pressure to 15MPa. At this time, the main cylinder provides a thrust of about 17000kN. Check the connection between the front support of the pile frame and the main cylinder pin plate. After confirming that there are no abnormalities, continue loading. S2.3 Third stage loading: Gradually and slowly load the main hydraulic cylinder to the rated working pressure of 22.5MPa, check the shape of the main hydraulic cylinder connecting hose, stop operating the valve group and conduct a pressure holding test; after the pressure holding test is completed, repeat the inspection of the key parts of the first and second stage loading to confirm that all components are working normally.

[0025] Step 3: Joint adjustment of the ultra-large hydraulic cylinder, including setting the working pressure of the three cylinders and setting the critical point for individual operation of the main hydraulic cylinder; The working pressure of the three cylinders is set as follows: synchronously and slowly pressurize to 16MPa, and the pile frame is separated from the support; pressurize the auxiliary cylinder separately until the pressure is consistent; before the auxiliary cylinder extends to the second stage cylinder, pressurize the main cylinder so that the pressure of the auxiliary cylinder drops to below 12MPa, and the pressure of the main cylinder is maintained at around 16MPa. The specific process for setting the critical point for the independent operation of the main cylinder is as follows: After the extra-large cylinder is fully extended, the main cylinder is operated to fall back. When the pressure rises to 18MPa, it stops. The critical point is recorded and calibrated. After calibration, the pressure of the main cylinder is ≤18MPa and the pressure of the auxiliary cylinder is 0 under the critical point state. Step three specifically involves: S3.1 Three-cylinder working pressure setting: Before joint commissioning and startup, the pressure of the three cylinders is controlled by the control module to increase synchronously and slowly until the pressure reaches 16MPa, at which point the pile frame is lifted and detached from the support. At this point, the three-cylinder linkage operation is stopped. If the pressure drop of the auxiliary cylinder is significant, the pressure of the auxiliary cylinder is replenished separately to ensure that the operating status of the super-large cylinder system is consistent. Before the auxiliary cylinder is close to the extension of the secondary cylinder, the pressure of the main cylinder is replenished so that the pressure of the auxiliary cylinder drops below 12MPa (matching the pressure threshold of the secondary safety valve of the auxiliary cylinder), and the pressure of the main cylinder is maintained at around 16MPa, thus completing the pressure setting. S3.2 Setting the critical point for independent operation of the main cylinder: With the main cylinder and auxiliary cylinder fully extended, the main cylinder is operated to fall back through the control module. The pressure of the main cylinder is monitored in real time. When the pressure rises to 18MPa (80% of the rated pressure), the fall stops. This position is recorded as the critical point and the system is calibrated. After calibration, the pressure of the main cylinder is ≤18MPa and the pressure of the auxiliary cylinder is 0 in the critical point state, realizing a safe switch from three-cylinder operation to single main cylinder operation.

[0026] Step 4: Main cylinder winch replacement operation, including preparation before winch replacement, slide rail switching and centering pin installation. First, check and correct the dimensions of the winch replacement slide rail; then control the main cylinder to slide along the slide rail to the rear support leg; finally, use the centering auxiliary module to achieve self-alignment and centering of the main cylinder and complete the pin installation.

[0027] Specifically: 4.1 Preparations before changing the winch: Check and correct the dimensions of the winch replacement slide, and grind it. Pay special attention to checking the dimensions of the slide at the rear support foot to ensure there is no structural interference. 4.2 Slide Switching: The main cylinder piston rod is retracted by the control module, so that the main cylinder is disengaged from the front support of the winch change and slides along the winch change slide to the rear support position. During the process, the pressure monitoring module monitors the pressure change in real time to avoid jamming or scraping. 4.3 Alignment Pin: After the main hydraulic cylinder reaches the rear support position, the joint bearing adjustment ring is used to limit the joint bearing deflection angle. The main hydraulic cylinder trunnion is self-aligned by the pin alignment adjustment block. After the pin insertion alignment accuracy is achieved, the pin installation is completed and the trunnion replacement operation is finished.

[0028] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for adjusting and replacing the winch of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame, characterized in that: Including the main hydraulic cylinder system, auxiliary hydraulic cylinder system, pressure monitoring module, centering auxiliary module, and control module, the specific steps for the joint commissioning and winch replacement of this ultra-large hydraulic cylinder are as follows: Step 1: Safety test of the auxiliary cylinder system, including structural strength safety test and cylinder reset test, during which the main cylinder system is locked; The structural strength safety test is as follows: the first-stage cylinder of the auxiliary oil cylinder is extended, the piston rod insert supports the pile frame pin, and the pressure is gradually increased to 5MPa and checked; after confirming that there is no abnormality, the pressure is increased by 5MPa and checked once, until the pressure is increased to 22MPa. After confirming that the pressure is consistent, the hydraulic pump is shut off and a 1-hour pressure holding test is carried out. Step 2: Safety test of the main hydraulic cylinder system. A graded loading method is adopted. After each stage of loading is completed, the system is unloaded and the stress on the main components is checked. The first stage is pressurized to 5MPa, and after holding the pressure for 10 minutes, the contact surface matching is checked. The second stage is pressurized to 15MPa, and the connection parts are checked. The third stage is pressurized to 22.5MPa, and the pressure test is repeated. Step 3: Joint adjustment of the ultra-large hydraulic cylinder, including setting the working pressure of the three cylinders and setting the critical point for individual operation of the main hydraulic cylinder; Step 4: Main cylinder winch replacement operation, including preparation before winch replacement, slide rail switching and centering pin installation. First, check and correct the dimensions of the winch replacement slide rail; then control the main cylinder to slide along the slide rail to the rear support leg; finally, use the centering auxiliary module to achieve self-alignment and centering of the main cylinder and complete the pin installation.

2. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 1, characterized in that: The main hydraulic cylinder system includes a main hydraulic cylinder body, a front support for the winch replacement, a rear support leg, and a winch replacement slide. The main hydraulic cylinder body is located inside the pile frame truss. The bottom end of the main hydraulic cylinder body is connected to the hull base, and the top end is a piston rod. The piston rod end is provided with an ear structure with a joint bearing. The joint bearing cooperates with the pin on the front support for the winch replacement or the rear support leg to form a swingable mechanical connection. The winch replacement slide is located inside the truss and between the front support for the winch replacement and the rear support leg. It is used for guiding the switching of the main hydraulic cylinder hinge point. The auxiliary cylinder system includes an auxiliary cylinder body, a swing cylinder, and a return solenoid valve. The auxiliary cylinder body is a three-stage telescopic plunger cylinder. The auxiliary cylinder body is hingedly installed in the main hull near the middle of the hull. Its piston rod head is embedded in the load-bearing pin of the pile frame with a plug structure to support the load-bearing pin of the pile frame. The swing cylinder is connected to the auxiliary cylinder body and is used to drive the auxiliary cylinder body to vertically reset. The return solenoid valve is set in the return oil pipeline of the auxiliary cylinder body and is used to control the piston rod to fall back. The pressure monitoring module includes multiple pressure sensors, which are respectively installed on the oil inlet and return lines of the main cylinder body, the oil inlet and return lines of the auxiliary cylinder body, and the control panel, to monitor the local pressure of multiple cylinders and the pressure on the control panel in real time, ensuring that the pressure data is synchronized. The centering auxiliary module includes a spherical bearing adjusting ring and a pin centering adjusting block. The spherical bearing adjusting ring is fitted onto the outside of the spherical bearing at the end of the piston rod of the main cylinder. It is designed according to the maximum swing angle of the spherical bearing to limit the excessive deflection angle of the spherical bearing during the centering process. The pin centering adjusting block is installed on the pin bushing of the rear support leg, and its outer circle matches the pin bushing, while its inner circle matches the pin and the cylinder trunnion. It is used to achieve self-aligning centering of the main cylinder. The control module is electrically connected to the main cylinder system, the auxiliary cylinder system, and the pressure monitoring module, respectively, and is used to control the pressure loading, cylinder extension and retraction, and state switching during safety tests, joint commissioning, and winch replacement processes.

3. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 2, characterized in that: The switching slide has been dynamically simulated and optimized to avoid structural interference risks. The surface of the switching slide has been modified and polished to have a roughness of ≤Ra3.2μm, ensuring smooth switching of the main cylinder hinge point.

4. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 2, characterized in that: The pressure sensor has a measurement accuracy of no less than ±0.1MPa and a measurement range of 0-40MPa. It can provide real-time feedback on pressure changes, which facilitates the control module to adjust the pressure loading rate in a timely manner.

5. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 2, characterized in that: The spherical bearing adjusting ring is clearance-fitted with the spherical bearing, with a clearance of 0.3-0.5mm. A limiting structure is designed based on the maximum swing angle of 3° of the spherical bearing. The outer circle of the pin centering adjusting block is interference-fitted with the pin sleeve, and the inner circle of the pin centering adjusting block is clearance-fitted with the pin and the cylinder trunnion, with a clearance of 0.2-0.3mm.

6. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 1, characterized in that: In step two, the specific process of hierarchical loading is as follows: S2.1 First stage loading: The main cylinder valve group is operated through the control module to gradually increase the pressure of the main cylinder to 5MPa and hold the pressure for 10 minutes; after the pressure holding is completed, the main cylinder is retracted and the contact position and contact surface matching between the main cylinder and the support before the winch replacement are checked. Only after confirming that the matching is good can the next stage loading be carried out. S2.2 Second stage loading: Operate the main cylinder valve group to load the main cylinder pressure to 15MPa, check the connection between the front support of the pile frame and the main cylinder pin plate, and continue loading after confirming that there are no abnormalities. S2.3 Third stage loading: Gradually and slowly load the main hydraulic cylinder to the rated working pressure of 22.5MPa, check the shape of the main hydraulic cylinder connecting hose, stop operating the valve group and conduct a pressure holding test; after the pressure holding test is completed, repeat the inspection of the key parts of the first and second stage loading to confirm that all components are working normally.

7. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 1, characterized in that: Step three specifically involves: S3.1 Three-cylinder working pressure setting: Before joint commissioning and start-up, the pressure of the three cylinders is controlled by the control module to increase slowly and synchronously until the pressure rises to 16MPa, and the pile frame is lifted and detached from the support. At this time, the three-cylinder linkage operation is stopped. If the pressure drop of the auxiliary cylinder is obvious, the pressure of the auxiliary cylinder is replenished separately to ensure that the operating status of the ultra-large cylinder system is consistent. Before the auxiliary cylinder extends close to the secondary cylinder, the main cylinder is pressurized to reduce the pressure of the auxiliary cylinder to below 12MPa, thus completing the pressure setting. S3.2 Setting the critical point for independent operation of the main cylinder: With the main cylinder and auxiliary cylinder fully extended, the main cylinder is operated to fall back through the control module. The pressure of the main cylinder is monitored in real time. When the pressure rises to 18MPa (80% of the rated pressure), the fall is stopped. This position is recorded as the critical point and the system is calibrated. After calibration, the main cylinder pressure is ≤18MPa and the auxiliary cylinder pressure is 0 at the critical point, realizing a safe switch from three-cylinder operation to single main cylinder operation.

8. The method for joint adjustment and winch replacement of an ultra-large hydraulic cylinder on a marine engineering vessel's pile frame according to claim 1, characterized in that: Step four specifically involves: 4.1 Preparations before changing the winch: Check and correct the dimensions of the winch replacement slide, and grind it. Pay special attention to checking the dimensions of the slide at the rear support foot to ensure there is no structural interference. 4.2 Slide Switching: The main cylinder piston rod is retracted by the control module, so that the main cylinder is disengaged from the front support of the winch change and slides along the winch change slide to the rear support position. During the process, the pressure monitoring module monitors the pressure change in real time to avoid jamming or scraping. 4.3 Alignment Pin: After the main hydraulic cylinder reaches the rear support position, the joint bearing adjustment ring is used to limit the joint bearing deflection angle. The main hydraulic cylinder trunnion is self-aligned by the pin alignment adjustment block. After the pin insertion alignment accuracy is achieved, the pin installation is completed and the trunnion replacement operation is finished.