Follow-up compensation method capable of keeping normal work in emergency

Through the design of follow-up pulley and follow-up oil cylinder, combined with multiple accumulators and hydraulic control oil circuits, the problem of cargo-to-ship distance maintenance problems in the offshore supply crane in emergency situations and insufficient oil pressure caused by accumulator failure is solved. The problem is to achieve safety and stability of the lifting process.

CN119263100AActive Publication Date: 2025-01-07SOUTH CHINA MARINE MACHINERY
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Patent Information

Application Number
CN202411361766.2
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2024-09-27
Publication Date
2025-01-07
Estimated Expiration
2044-09-27

AI Technical Summary

Technical Problem

In an emergency, the compensation system of the offshore supply crane is prone to failure to maintain the distance between the cargo and the ship, which may lead to cargo collisions. A single accumulator cannot ensure the stability of the oil pressure during the failure, which affects the normal oil circuit. run.

Method used

The follow-up compensation system is adopted, and the follow-up oil cylinder is connected to the follow-up oil cylinder, which drives the lifting hook and cargo to float along with the supply ship. The design of two accumulators and hydraulic control oil circuits is used to ensure that another energy storage is stored in the event of a failure. The device can continue to supply oil to prevent insufficient oil pressure.

Benefits of technology

Maintain a safe distance between the cargo and the ship in an emergency, ensure safety of the lifting process, and prevent insufficient oil pressure caused by accumulator failure.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention provides a follow-up compensation method capable of keeping normal work in emergency. The follow-up compensation method comprises the following specific steps: (7) when a supply ship sinks; (71) the supply ship pulls the follow-up pulley to move through the follow-up cable; (72) the moving pressure of the follow-up tackle overcomes the external thrust of the follow-up oil cylinder, and a piston rod of the follow-up oil cylinder is pushed by the follow-up tackle to retract inwards; (73) hydraulic oil at the rodless end of the follow-up oil cylinder is pushed to flow back to the first energy accumulator and the second energy accumulator through the first oil way and the second oil way; (8) when the supply ship floats upwards; (81) the tension of the follow-up cable between the supply ship and the follow-up tackle is reduced; (82) the oil pressure of a first energy accumulator and the oil pressure of a second energy accumulator overcome the moving pressure of the follow-up tackle, and hydraulic oil flows into the rodless end of a follow-up oil cylinder through a first oil way and a second oil way; and (83) a piston rod of the follow-up oil cylinder is pushed by the hydraulic oil to extend outwards, so that the follow-up pulley is driven to move and tension the follow-up cable.
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Description

Technical Field

[0001] The invention relates to the technical field of crane control systems, and in particular to a follow-up compensation method capable of maintaining normal operation in an emergency situation. Background Art

[0002] The crane on the ship platform is used for offshore replenishment. Due to the influence of wind and waves, the ship carrying out offshore replenishment will sway irregularly with the waves, which seriously affects the efficiency of offshore replenishment. Therefore, wave compensation must be performed on the offshore replenishment device to improve the efficiency of offshore replenishment.

[0003] For example, the Chinese patent application CN202222608238.5, with an announcement date of 2023.04.11, discloses a crane compensation mechanism that can compensate for the shaking between ships.

[0004] The compensation mechanism of this document achieves compensation by driving the compensation trolley to move through the compensation cylinder. However, if there is no emergency strategy, then in an emergency situation, if the driving oil circuit of the compensation cylinder fails, it is easy to cause the compensation trolley to be unable to move and unable to perform sway compensation in time, thereby causing a collision between the cargo and the ship. In addition, only one accumulator cannot ensure that the oil pressure can be reliably provided when the accumulator is damaged. At the same time, if the damaged accumulator is not closed in time, the accumulator will absorb the oil pressure in the entire oil circuit, resulting in the problem of insufficient oil pressure in the entire oil circuit. Summary of the invention

[0005] The present invention provides a follow-up compensation method that can maintain normal operation in an emergency situation, ensure that a certain safety distance is always maintained between the cargo and the ship, and ensure normal operation in an emergency situation to prevent sudden accidents, while preventing the accumulator from affecting the oil pressure in the entire oil circuit.

[0006] To achieve the above object, the technical solution of the present invention is: a servo compensation method capable of maintaining normal operation in an emergency situation, which is implemented by a servo compensation system, wherein the servo compensation system includes a hydraulic control oil circuit and a servo oil cylinder, a first accumulator and a second accumulator, and the specific steps include: (1) The crane drives the lifting hook to lift the load through the cargo winch.

[0007] (2) The follower hook is driven by the follower winch to connect to the supply ship.

[0008] (3) The follower block moves as the supply ship floats.

[0009] (4) The servo-controlled reversing valve is electrically switched, and the P end of the servo-controlled reversing valve is connected to the B end.

[0010] (5) The hydraulic oil in the second oil circuit flows to the control ends of the first logic valve and the second logic valve through the follow-up control reversing valve, and the first logic valve and the second logic valve are opened.

[0011] (6) The hydraulic oil of the first accumulator and the second accumulator flows into the rodless end of the follower cylinder through the first oil passage and the second oil passage.

[0012] (7) When the supply ship sinks, the supply ship moves by pulling the follower pulley with the follower cable.

[0013] The pressure of the follower pulley movement overcomes the outward thrust of the follower cylinder, and the piston rod of the follower cylinder is pushed inward by the follower pulley to retract. The hydraulic oil at the rodless end of the follower cylinder is pushed back to the first accumulator and the second accumulator through the first oil path and the second oil path.

[0014] (9) As the follower pulley moves, the lifting hook is also driven to move together to ensure that a certain distance is always maintained between the cargo and the supply ship.

[0015] (10) During the follow-up operation, if an accumulator fails, the control ball valve connected to the failed accumulator is closed, so that the failed accumulator cannot replenish hydraulic oil or output hydraulic oil. The other accumulator works normally to deliver hydraulic oil to the follow-up cylinder.

[0016] The above method connects the follower cylinder to the follower pulley. When the main ship transports goods between the main ship and the supply ship, the crane drives the lifting hook to lift the goods through the cargo winch. At the same time, the follower winch is connected to the supply ship through the follower hook. Therefore, when the supply ship and the main ship float up and down due to the wind and waves at sea, since the lifting hook and the follower hook are both connected to the follower pulley, the follower pulley moves with the floating of the supply ship, and the follower pulley moves while driving the lifting hook to move together, so that the goods lifted by the lifting hook can always maintain a certain floating distance with the supply ship, thereby preventing the goods from directly hitting the ship, and driving the follower pulley to move while following the supply ship to move while driving the follower oil cylinder to lift the goods. The cylinder performs telescopic movement. At this time, the follow-up control reversing valve is electrically reversed, so that the P end of the follow-up control reversing valve is connected to the B end, and the hydraulic oil in the second oil circuit flows to the control ends of the first logic valve and the second logic valve through the follow-up control reversing valve. The first logic valve and the second logic valve are opened, and the hydraulic oil of the accumulator flows into the rodless end of the follow-up cylinder through the first oil circuit and the second oil circuit. When the supply ship sinks, the supply ship moves by pulling the follow-up pulley through the follow-up cable. The pressure of the movement of the follow-up pulley overcomes the outward thrust of the follow-up cylinder, so that the piston rod of the follow-up cylinder is pushed inward and retracted, so that the hydraulic oil at the rodless end of the follow-up cylinder is pushed and passes through the first oil circuit and The second oil circuit flows back to the accumulator, and when the supply ship floats up, the tension of the follower cable between the supply ship and the follower block becomes smaller, and the oil pressure of the accumulator overcomes the pressure of the follower block moving, so that the accumulator outputs hydraulic oil to the follower cylinder, and the hydraulic oil flows into the rodless end of the follower cylinder through the first oil circuit and the second oil circuit, thereby pushing the piston rod of the follower cylinder to extend outward, thereby driving the follower block to move and tighten the follower cable, so that the follower block moves according to the floating of the supply ship, and the lifting hook is driven to move together with the follower block to ensure that a certain distance is always maintained between the cargo and the supply ship, avoiding accidental collision between the cargo and the supply ship, and ensuring the lifting. The process is set up; at the same time, two accumulators are set, and a control ball valve is set between the accumulator and the first oil circuit and the second oil circuit, and the control ball valve is in a normally open state. Therefore, in normal operation, the accumulator can normally deliver hydraulic oil to the follower cylinder. If one of the accumulators fails, the control ball valve connected to the accumulator is controlled to close, so that the failed accumulator cannot replenish the hydraulic oil or output the hydraulic oil, so that the other accumulator can continue to replenish the oil to the follower cylinder normally, and the closing of the control ball valve can prevent the failed accumulator from absorbing the hydraulic oil in the oil circuit and causing the problem of insufficient hydraulic oil in the oil circuit.

[0017] Furthermore, the hydraulic control oil circuit includes a follow-up control reversing valve, a first logic valve, a second logic valve, a first accumulator and a second accumulator. The first accumulator and the second accumulator are connected to one end of the first logic valve through the first oil circuit on the one hand, and the first accumulator is connected to one end of the second logic valve through the second oil circuit on the other hand. The other end of the first logic valve and the other end of the second logic valve are connected to the rodless end of the follow-up cylinder; a follow-up control reversing valve is provided on the second oil circuit, the P end of the follow-up control reversing valve is connected to the second oil circuit, the T end of the follow-up control reversing valve is connected to the oil tank, and the B end of the follow-up control reversing valve is connected to the control ends of the first logic valve and the second logic valve.

[0018] A first control ball valve is provided on the oil outlet end of the first accumulator, and the first control ball valve is in a normally open state; a second control ball valve is provided on the oil outlet end of the second accumulator, and the second control ball valve is in a normally open state.

[0019] The above arrangement, by setting the connection relationship between the first accumulator and the second accumulator, and the connection between the corresponding hydraulic control oil circuit and the follower cylinder, can conveniently supply oil to the follower cylinder after controlling the follower control reversing valve for reversing, and at the same time, it can flow back to the accumulator through the first oil circuit and the second oil circuit, and the oil circuit connection is simple.

[0020] Further, (8) when the supply ship floats up.

[0021] (81) The tension of the follower cable between the supply ship and the follower pulley decreases.

[0022] (82) The oil pressure of the first accumulator and the second accumulator overcomes the pressure of the follower pulley moving, and the first accumulator and the second accumulator output hydraulic oil to the rodless end of the follower cylinder. The hydraulic oil flows into the rodless end of the follower cylinder through the first oil path and the second oil path.

[0023] (83) The piston rod of the follower cylinder is pushed outward by the hydraulic oil, thereby driving the follower pulley to move and tighten the follower cable.

[0024] The above arrangement can also provide reliable compensation when the supply ship floats.

[0025] Furthermore, the first accumulator and the second accumulator are also connected to the oil tank, and a one-way valve is provided between the oil tank and the first accumulator and the second accumulator, wherein the oil inlet end of the one-way valve is connected to the oil tank, and the oil outlet end of the one-way valve is connected to the first accumulator and the second accumulator.

[0026] With the above arrangement, the hydraulic oil is replenished into the first accumulator and the second accumulator through the oil tank to replenish the hydraulic oil in time, and the one-way valve is arranged so that the hydraulic oil will not flow back into the oil tank.

[0027] Furthermore, a first safety valve group is provided between the first accumulator and the first oil circuit and the second oil circuit, the first safety valve group comprising a first safety relief valve and a first safety ball valve, the oil inlet end of the first safety relief valve is connected to the first accumulator, the oil outlet end of the first safety relief valve is connected to the oil tank, one end of the first safety ball valve is connected to the first accumulator, the other end of the first safety ball valve is connected to the oil tank, and the first safety ball valve is normally closed.

[0028] The above arrangement, through the arrangement of the first safety valve group, enables that when the first accumulator needs to be maintained, the first safety ball valve can be opened, thereby allowing the hydraulic oil in the first accumulator to flow back to the oil tank, thereby facilitating maintenance of the first accumulator.

[0029] Furthermore, a second safety valve group is provided between the second accumulator and the first oil circuit and the second oil circuit, the second safety valve group includes a second safety overflow valve and a second safety ball valve, the oil inlet end of the second safety overflow valve is connected to the second accumulator, the oil outlet end of the second safety overflow valve is connected to the oil tank, one end of the second safety ball valve is connected to the second accumulator, the other end of the second safety ball valve is connected to the oil tank, and the second safety ball valve is normally closed.

[0030] The above arrangement, through the arrangement of the second safety valve group, enables that when the second accumulator needs to be maintained, the second safety ball valve can be opened, thereby allowing the hydraulic oil in the second accumulator to flow back to the oil tank, thereby facilitating maintenance of the second accumulator.

[0031] Furthermore, a pressure switch is provided between the first accumulator and the oil tank.

[0032] The above arrangement, through the arrangement of the pressure switch, enables the pressure switch to control the oil tank to replenish oil when the oil pressure of the hydraulic oil in the first accumulator is insufficient.

[0033] Furthermore, a second pressure switch is provided between the second accumulator and the oil tank.

[0034] The above arrangement, through the arrangement of the second pressure switch, enables the second pressure switch to control the oil tank to replenish oil when the oil pressure of the hydraulic oil in the second accumulator is insufficient.

[0035] Furthermore, the rod end of the follower cylinder is connected to the oil tank through a third oil circuit, and a reset reversing valve is provided on the third oil circuit, the P end of the reset reversing valve is connected to the oil inlet end of the oil tank, the T end of the reset reversing valve is connected to the oil return end of the oil tank, and the A end of the reset reversing valve is connected to the rod end of the follower cylinder.

[0036] The above arrangement, by setting up the third oil circuit, makes it possible for the follower cylinder to retract the piston rod when the follower pulley stops working, and the reset reversing valve is controlled to be electrically reversed so that the P end of the reset reversing valve is connected to the A end, thereby the hydraulic oil output from the oil tank flows into the rod end of the follower cylinder through the reset reversing valve, thereby driving the piston rod of the follower cylinder to retract into the cylinder body of the follower cylinder.

[0037] Furthermore, the rodless end of the follower cylinder is also connected to the oil tank through an oil leakage reversing valve, the P end of the oil leakage reversing valve is connected to the rodless end of the follower cylinder, the T end of the oil leakage reversing valve is connected to the oil tank, and the control end of the oil leakage reversing valve is connected to the A end of the reset reversing valve.

[0038] According to the above arrangement, when it is necessary to retract the piston rod of the follower cylinder, the follower control reversing valve is switched and closed, so that the first logic valve and the second logic valve are closed, and the first accumulator cannot deliver hydraulic oil to the rodless end of the follower cylinder; at this time, by controlling the reversing of the oil leakage reversing valve, the P end of the oil leakage reversing valve is connected to the T end, thereby, when the piston rod of the follower cylinder is retracted, the hydraulic oil can be pushed back to the oil tank through the oil leakage reversing valve, so that the piston rod of the follower cylinder can be retracted into the cylinder body. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the hydraulic system of the present invention.

[0040] Figure 2 for Figure 1 Enlarged view of point C in the middle.

[0041] Figure 3 for Figure 1 Enlarged view of D in the middle.

[0042] Figure 4 It is a working principle diagram of the present invention. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] like Figure 1-Figure 3As shown, a follow-up compensation system includes a hydraulic control oil circuit and a follow-up oil cylinder 2, wherein the follow-up oil cylinder 2 is connected to a follow-up pulley (not shown in the figure), the follow-up pulley is slidably arranged on a boom of a crane (not shown in the figure), the follow-up pulley is connected to a follow-up hook through a follow-up cable and to a lifting hook through a lifting cable (not shown in the figure), the hydraulic control oil circuit 1 includes a follow-up control reversing valve 11, a first logic valve 12, a second logic valve 13, a first accumulator 14 and a second accumulator 16, wherein the first accumulator 14 and the second accumulator 16 are connected by The first oil circuit 21 is connected to one end of the first logic valve 12, and the first accumulator 14 is connected to one end of the second logic valve 13 through the second oil circuit 22. The other end of the first logic valve 12 and the other end of the second logic valve 13 are connected to the rodless end 23 of the follow-up cylinder 2; a follow-up control reversing valve 11 is provided on the second oil circuit 22, the P end of the follow-up control reversing valve 11 is connected to the second oil circuit 22, the T end of the follow-up control reversing valve 11 is connected to the oil tank 01, and the B end of the follow-up control reversing valve 11 is connected to the control ends of the first logic valve 12 and the second logic valve 13.

[0045] like Figure 3 As shown, a first control ball valve 141 is provided at the oil outlet of the first accumulator 14, and the first control ball valve 141 is in a normally open state; a second control ball valve 161 is provided at the oil outlet of the second accumulator 16, and the second control ball valve 161 is in a normally open state.

[0046] The first accumulator 14 and the second accumulator 16 are also connected to the oil tank 01. A one-way valve 011 is provided between the oil tank 01 and the first accumulator 14 and the second accumulator 16. The oil inlet end of the one-way valve 011 is connected to the oil tank 01, and the oil outlet end of the one-way valve 011 is connected to the first accumulator 14 and the second accumulator 16. The hydraulic oil is replenished to the first accumulator 14 and the second accumulator through the oil tank 01 to replenish the hydraulic oil in time, and the one-way valve 011 is set so that the hydraulic oil will not flow back to the oil tank 01. A pressure switch 012 is also provided between the first accumulator 14 and the oil tank 01. Through the setting of the pressure switch 012, when the oil pressure of the hydraulic oil in the first accumulator 14 is insufficient, the pressure switch 012 controls the oil tank 01 to replenish the oil. A second pressure switch 013 is provided between the second accumulator 16 and the oil tank 01. The above configuration, through the configuration of the second pressure switch 013, enables the second pressure switch 013 to control the oil tank 01 to replenish oil when the oil pressure of the hydraulic oil in the second accumulator 16 is insufficient.

[0047] like Figure 1 and Figure 3As shown, a first safety valve group 15 is also provided between the first accumulator 14 and the first oil circuit 21 and the second oil circuit 22. The first safety valve group 15 includes a first safety relief valve 151 and a first safety ball valve 152. The oil inlet end of the first safety relief valve 151 is connected to the first accumulator 14, and the oil outlet end of the first safety relief valve 151 is connected to the oil tank 01. One end of the first safety ball valve 152 is connected to the first accumulator 14, and the other end of the first safety ball valve 152 is connected to the oil tank 01. The first safety ball valve 152 is normally closed. Through the provision of the first safety valve group, when the first accumulator 14 needs to be maintained, the first safety ball valve 152 is opened, so that the hydraulic oil in the first accumulator 14 can be drained back to the oil tank 01, thereby facilitating the maintenance of the first accumulator 14.

[0048] like Figure 1 and Figure 3 As shown, a second safety valve group 17 is also provided between the second accumulator 16 and the first oil circuit 21 and the second oil circuit 22. The second safety valve group 17 includes a second safety relief valve 171 and a second safety ball valve 172. The oil inlet end of the second safety relief valve 171 is connected to the second accumulator 16, the oil outlet end of the second safety relief valve 171 is connected to the oil tank 01, one end of the second safety ball valve 172 is connected to the second accumulator 16, and the other end of the second safety ball valve 172 is connected to the oil tank 01. The second safety ball valve 172 is normally closed. The above arrangement, through the arrangement of the second safety valve group 17, allows the hydraulic oil in the second accumulator 16 to be drained back to the oil tank 01 by opening the second safety ball valve 172 when the second accumulator 16 needs to be maintained, thereby facilitating the maintenance of the second accumulator 16.

[0049] The rod end 24 of the follower cylinder 2 is connected to the oil tank 01 through the third oil circuit 25. A reset reversing valve 26 is provided on the third oil circuit 01. The P end of the reset reversing valve 26 is connected to the oil inlet end of the oil tank 01, the T end of the reset reversing valve 26 is connected to the oil return end of the oil tank 01, and the A end of the reset reversing valve 26 is connected to the rod end 24 of the follower cylinder 2. By providing the third oil circuit 25, when the follower pulley is to stop working, the follower cylinder 2 needs to retract the piston rod, and the reset reversing valve 26 is controlled to be electrically reversed, so that the P end of the reset reversing valve 26 is connected to the A end, so that the hydraulic oil output from the oil tank 01 flows into the rod end of the follower cylinder 2 through the reset reversing valve 26, thereby driving the piston rod of the follower cylinder 2 to retract into the cylinder body of the follower cylinder 2.

[0050] The rodless end 23 of the follower cylinder 2 is also connected to the oil tank 01 through the oil leakage reversing valve 27, the P end of the oil leakage reversing valve 27 is connected to the rodless end 23 of the follower cylinder 2, the T end of the oil leakage reversing valve 27 is connected to the oil tank, and the control end X of the oil leakage reversing valve 27 is connected to the A end of the reset reversing valve 26. When the piston rod of the follower cylinder 2 needs to be retracted, the follower control reversing valve 11 is switched closed, so that the first logic valve 12 and the second logic valve 13 are closed, and the first accumulator 14 cannot deliver hydraulic oil to the rodless end of the follower cylinder 2; at this time, by controlling the reversing of the oil leakage reversing valve 27, the P end of the oil leakage reversing valve 27 is connected to the T end, so that when the piston rod of the follower cylinder 2 is retracted, the hydraulic oil can be pushed back to the oil tank through the oil leakage reversing valve 27, so that the piston rod of the follower cylinder 2 can be retracted into the cylinder body.

[0051] like Figure 4 As shown, a working method of a follow-up compensation system includes the following specific steps: (1) The crane drives the lifting hook to lift the load through the cargo winch.

[0052] (2) The follower hook is driven by the follower winch to connect to the supply ship.

[0053] (3) The follower block moves as the supply ship floats.

[0054] (4) The servo control reversing valve 11 is electrically switched, and the P end of the servo control reversing valve 11 is connected to the B end.

[0055] (5) The hydraulic oil in the second oil circuit 22 flows to the control ends of the first logic valve 12 and the second logic valve 13 through the follow-up control reversing valve 11, and the first logic valve 12 and the second logic valve 13 are opened.

[0056] (6) The hydraulic oil in the first accumulator 14 and the second accumulator 16 flows into the rod end 23 of the slave cylinder 2 through the first oil passage 21 and the second oil passage 22 .

[0057] (7) When the supply ship sinks.

[0058] (71) The supply ship moves by pulling the follower block with the follower cable.

[0059] (72) The pressure of the follower pulley moving overcomes the outward thrust of the follower cylinder 2, and the piston rod of the follower cylinder 2 is pushed inward and retracted by the follower pulley.

[0060] (73) The hydraulic oil in the rodless end 23 of the slave cylinder 2 is pushed through the first oil passage 21 and the second oil passage 22 to flow back to the first accumulator 14 and the second accumulator 16 .

[0061] (8) When the supply ship surfaces.

[0062] (81) The tension of the follower cable between the supply ship and the follower pulley decreases.

[0063] (82) The oil pressure of the first accumulator 14 and the second accumulator 16 overcomes the pressure of the follower pulley, and the first accumulator 14 and the second accumulator 16 output hydraulic oil to the rodless end 23 of the follower cylinder 2. The hydraulic oil flows into the rodless end 23 of the follower cylinder 2 through the first oil path 21 and the second oil path 22.

[0064] (83) The piston rod of the follower cylinder 2 is pushed outward by the hydraulic oil, thereby driving the follower pulley to move and tighten the follower cable.

[0065] (9) As the follower pulley moves, the lifting hook is also driven to move together to ensure that a certain distance is always maintained between the cargo and the supply ship.

[0066] (10) During the follow-up operation, if an accumulator fails.

[0067] (11) The control ball valve connected to the faulty accumulator is closed, so that the faulty accumulator cannot replenish hydraulic oil or output hydraulic oil.

[0068] (12) The other accumulator operates normally and delivers hydraulic oil to the follower cylinder.

[0069] The working principle of the present invention is as follows: by connecting the follower cylinder 2 to the follower pulley, when the main ship needs to transport cargo between the main ship and the supply ship, the crane drives the lifting hook to lift the cargo through the cargo winch, and at the same time, the follower winch is connected to the supply ship through the follower hook. Therefore, when the supply ship and the main ship float up and down due to the wind and waves at sea, since the lifting hook and the follower hook are both connected to the follower pulley, the follower pulley moves with the floating of the supply ship, and the follower pulley moves while driving the lifting hook to move together, so that the cargo lifted by the lifting hook can always maintain a certain floating distance with the supply ship, thereby preventing the cargo from directly hitting the ship, and the follower pulley drives the follower cylinder 2 to extend while following the movement of the supply ship. At this time, the follow-up control reversing valve 11 is electrically reversed, so that the P end of the follow-up control reversing valve 11 is connected to the B end, and the hydraulic oil in the second oil circuit 22 flows to the control ends of the first logic valve 12 and the second logic valve 13 through the follow-up control reversing valve 11. The first logic valve 12 and the second logic valve 13 are opened, and the hydraulic oil of the accumulator flows into the rodless end of the follow-up cylinder 2 through the first oil circuit 21 and the second oil circuit 22. When the supply ship sinks, the supply ship moves by pulling the follow-up pulley through the follow-up cable. The pressure of the movement of the follow-up pulley overcomes the outward thrust of the follow-up cylinder 2, so that the piston rod of the follow-up cylinder 2 is pushed inward and retracted, so that the hydraulic oil at the rodless end of the follow-up cylinder 2 is The oil is pushed and flows back to the accumulator through the first oil circuit 21 and the second oil circuit 22. When the supply ship floats up, the tension of the follower cable between the supply ship and the follower block becomes smaller, and the oil pressure of the accumulator overcomes the pressure of the follower block moving, so that the accumulator outputs hydraulic oil to the follower cylinder 2. The hydraulic oil flows into the rodless end of the follower cylinder 2 through the first oil circuit 21 and the second oil circuit 22, and then pushes the piston rod of the follower cylinder 2 to extend outward, thereby driving the follower block to move and tighten the follower cable, so that the follower block moves according to the floating of the supply ship, and the lifting hook moves together with the follower block to ensure that a certain distance is always maintained between the cargo and the supply ship to avoid the cargo and the supply ship In case of accidental collision, the safety of the lifting process is ensured; at the same time, two accumulators are arranged, and a control ball valve is arranged between the accumulator and the first oil circuit and the second oil circuit, and the control ball valve is in a normally open state. Therefore, in normal operation, the accumulator can normally deliver hydraulic oil to the follower cylinder. If one of the accumulators fails, the control ball valve connected to the accumulator is controlled to close, so that the failed accumulator cannot replenish the hydraulic oil or output the hydraulic oil, so that the other accumulator can continue to replenish the hydraulic oil to the follower cylinder normally, and the closing of the control ball valve can prevent the failed accumulator from absorbing the hydraulic oil in the oil circuit and causing insufficient hydraulic oil in the oil circuit.

Claims

1. A servo compensation method capable of maintaining normal operation in an emergency situation, which is implemented by a servo compensation system, wherein the servo compensation system comprises a hydraulic control oil circuit and a servo oil cylinder, a first accumulator and a second accumulator, and is characterized in that: The specific steps include: (1) The crane drives the lifting hook to lift the load through the cargo winch; (2) The follower hook is driven by the follower winch to connect to the supply ship; (3) The follower block moves with the floating of the supply ship; (4) The servo control reversing valve is electrically switched, and the P end of the servo control reversing valve is connected to the B end; (5) The hydraulic oil in the second oil circuit flows to the control ends of the first logic valve and the second logic valve through the follow-up control reversing valve, and the first logic valve and the second logic valve are opened; (6) The hydraulic oil of the first accumulator and the second accumulator flows into the rodless end of the follower cylinder through the first oil passage and the second oil passage; (7) When the supply ship sinks, the supply ship moves by pulling the follower pulley with the follower cable; The pressure of the follower pulley moving overcomes the outward thrust of the follower cylinder, and the piston rod of the follower cylinder is pushed inward by the follower pulley to retract; the hydraulic oil at the rodless end of the follower cylinder is pushed back to the first accumulator and the second accumulator through the first oil circuit and the second oil circuit; (9) When the follower block moves, the lifting hook is driven to move together to ensure that a certain distance is always maintained between the cargo and the supply ship; (10) During the follow-up operation, if an accumulator fails, the control ball valve connected to the failed accumulator is closed, so that the failed accumulator cannot replenish hydraulic oil or output hydraulic oil; the other accumulator works normally to deliver hydraulic oil to the follow-up cylinder.

2. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 1, characterized in that: The hydraulic control oil circuit includes a servo control reversing valve, a first logic valve, a second logic valve, a first accumulator and a second accumulator. The first accumulator and the second accumulator are connected to one end of the first logic valve through the first oil circuit on one hand, and the first accumulator is connected to one end of the second logic valve through the second oil circuit on the other hand. The other end of the first logic valve and the other end of the second logic valve are connected to the rodless end of the servo oil cylinder; a servo control reversing valve is provided on the second oil circuit, the P end of the servo control reversing valve is connected to the second oil circuit, the T end of the servo control reversing valve is connected to the oil tank, and the B end of the servo control reversing valve is connected to the control ends of the first logic valve and the second logic valve; A first control ball valve is provided on the oil outlet end of the first accumulator, and the first control ball valve is in a normally open state; a second control ball valve is provided on the oil outlet end of the second accumulator, and the second control ball valve is in a normally open state.

3. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 1, characterized in that: Between steps (7) and (9) also includes: step (8) when the supply ship floats up; (81) the tension of the follower cable between the supply ship and the follower pulley decreases; (82) the oil pressure of the first accumulator and the second accumulator overcomes the pressure of the follower pulley moving, and the first accumulator and the second accumulator output hydraulic oil to the rodless end of the follower cylinder, and the hydraulic oil flows into the rodless end of the follower cylinder through the first oil circuit and the second oil circuit; (83) the piston rod of the follower cylinder is pushed outward by the hydraulic oil, thereby driving the follower pulley to move and tighten the follower cable.

4. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 1, characterized in that: The first accumulator and the second accumulator are also connected to the oil tank. A one-way valve is provided between the oil tank and the first accumulator and the second accumulator. The oil inlet end of the one-way valve is connected to the oil tank, and the oil outlet end of the one-way valve is connected to the first accumulator and the second accumulator.

5. The method of claim 1 for maintaining normal operation in an emergency is characterized in that: A first safety valve group is also provided between the first accumulator and the first oil circuit and the second oil circuit. The first safety valve group includes a first safety relief valve and a first safety ball valve. The oil inlet end of the first safety relief valve is connected to the first accumulator, and the oil outlet end of the first safety relief valve is connected to the oil tank. One end of the first safety ball valve is connected to the first accumulator, and the other end of the first safety ball valve is connected to the oil tank. The first safety ball valve is normally closed.

6. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 2, characterized in that: A second safety valve group is also provided between the second accumulator and the first oil circuit and the second oil circuit. The second safety valve group includes a second safety overflow valve and a second safety ball valve. The oil inlet end of the second safety overflow valve is connected to the second accumulator, and the oil outlet end of the second safety overflow valve is connected to the oil tank. One end of the second safety ball valve is connected to the second accumulator, and the other end of the second safety ball valve is connected to the oil tank. The second safety ball valve is normally closed.

7. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 2, characterized in that: A pressure switch is also provided between the first accumulator and the oil tank.

8. The method of claim 2 for maintaining normal operation in an emergency is characterized in that: A second pressure switch is provided between the second energy storage device and the oil tank.

9. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 1, characterized in that: The rod end of the follower cylinder is connected to the oil tank through the third oil circuit, and a reset reversing valve is provided on the third oil circuit. The P end of the reset reversing valve is connected to the oil inlet end of the oil tank, the T end of the reset reversing valve is connected to the oil return end of the oil tank, and the A end of the reset reversing valve is connected to the rod end of the follower cylinder.

10. A follow-up compensation method capable of maintaining normal operation in an emergency situation according to claim 8, characterized in that: The rodless end of the follower cylinder is also connected to the oil tank through an oil leakage reversing valve, the P end of the oil leakage reversing valve is connected to the rodless end of the follower cylinder, the T end of the oil leakage reversing valve is connected to the oil tank, and the control end of the oil leakage reversing valve is connected to the A end of the reset reversing valve.

Citation Information

Patent Citations

  • A crane compensation mechanism

    CN218841533U

  • Apparatus for transferring cargo between an ocean-located unit and a vessel

    GB1586842A

  • Wave-motion compensating apparatus for use in conjunction with an off-shore crane, or the like

    US4098082A

  • Method and apparatus for transferring cargo between an ocean-located unit and a vessel

    US4166545A

  • Offshore crane heave compensation control system and method using video rangefinding

    WO2017107936A1