A servo compensation method capable of maintaining normal operation in emergency situations

Abstract

The present invention provides a follow-up compensation method capable of maintaining normal operation in an emergency situation, and the specific steps include: (7) when the supply ship sinks; (71) the supply ship pulls the follow-up pulley to move by the follow-up cable; (72) the pressure of the follow-up pulley movement overcomes the outward thrust of the follow-up oil cylinder, and the piston rod of the follow-up oil cylinder is pushed inward and retracted by the follow-up pulley; (73) the hydraulic oil at the rodless end of the follow-up oil cylinder is pushed through the first oil circuit and the second oil circuit to flow back to the first accumulator and the second accumulator; (8) when the supply ship floats; (81) the tension of the follow-up cable between the supply ship and the follow-up pulley becomes smaller; (82) the oil pressure of the first accumulator and the second accumulator overcomes the pressure of the follow-up pulley movement, and the hydraulic oil flows into the rodless end of the follow-up oil cylinder through the first oil circuit and the second oil circuit; (83) the piston rod of the follow-up oil cylinder is pushed outward by the hydraulic oil, thereby driving the follow-up pulley to move and tighten the follow-up cable.

Description

Technical Field

[0001] The present invention relates to the technical field of crane control systems, and in particular to a servo 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 erratically with the waves, seriously affecting the efficiency of offshore replenishment. Therefore, wave compensation must be implemented on the offshore replenishment equipment to improve the efficiency of offshore replenishment.

[0003] For example, the Chinese patent application CN202222608238.5, published on April 11, 2023, 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, such as when the driving oil circuit of the compensation cylinder fails, it is easy for the compensation trolley to be unable to move and unable to perform shaking 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, thereby causing 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 emergency situations, ensure that a certain safe distance is always maintained between the cargo and the ship, and ensure normal operation in emergency situations to prevent sudden accidents. At the same time, it can prevent the accumulator from affecting the oil pressure in the entire oil circuit.

[0006] To achieve the above-mentioned 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. The servo compensation system includes a hydraulic control oil circuit and a servo cylinder, a first accumulator and a second accumulator. The specific steps include:

[0007] (1) The crane drives the lifting hook through the cargo winch to lift the load.

[0008] (2) The follower hook is driven by a follower winch to connect to the supply ship.

[0009] (3) The follower block moves as the supply ship floats.

[0010] (4) The servo control reversing valve is electrically reversed, and the P end of the servo control reversing valve is connected to the B end.

[0011] (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 servo control reversing valve, and the first logic valve and the second logic valve are opened.

[0012] (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.

[0013] (7) When the supply ship sinks, the supply ship moves by pulling the follower pulley with the follower cable.

[0014] The pressure of the follower block overcomes the outward thrust of the follower cylinder, and the piston rod of the follower cylinder is pushed inward by the follower block. The hydraulic oil in the rodless end of the follower cylinder is pushed through the first oil path and the second oil path to flow back to the first accumulator and the second accumulator.

[0015] (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.

[0016] (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 and supplies hydraulic oil to the follow-up cylinder.

[0017] The above method connects the follower oil cylinder to the follower pulley. When the main ship wants to transport cargo between the supply ship and the supply ship, the crane drives the lifting hook to lift the cargo 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 on the 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 movement of the follower pulley drives 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 colliding with the ship, and the follower pulley drives the follower oil cylinder to lift the cargo through the cargo winch. When the cylinder performs telescopic movement, the servo control reversing valve is electrically reversed, so that the P end of the servo 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 servo 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 servo cylinder through the first oil circuit and the second oil circuit. When the supply ship sinks, the supply ship moves by pulling the servo pulley through the servo cable. The pressure of the servo pulley overcomes the outward thrust of the servo cylinder, so that the piston rod of the servo cylinder is pushed inward and retracted, so that the hydraulic oil at the rodless end of the servo cylinder is pushed and passes through the first oil circuit and The second oil circuit flows back to the accumulator. 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 to move, so that the accumulator outputs hydraulic oil to the follower cylinder. The hydraulic oil flows into the rodless end of the follower cylinder through the first oil circuit and the second oil circuit, and then pushes 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. When the follower block moves, it drives the lifting hook to move together, ensuring 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 lifting. At the same time, two accumulators are provided, and a control ball valve is provided 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, during 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 normally replenish the oil to the follower cylinder. By closing the control ball valve, the failed accumulator is prevented from absorbing the hydraulic oil in the oil circuit, thereby causing insufficient hydraulic oil in the oil circuit.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] Further, (8) when the supply ship surfaces.

[0022] (81) The tension in the follower cable between the supply ship and the follower block decreases.

[0023] (82) The oil pressure of the first accumulator and the second accumulator overcomes the pressure of the follower pulley, 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.

[0024] (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.

[0025] The above settings can also provide reliable compensation when the supply ship floats.

[0026] 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, 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.

[0027] 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 to prevent the hydraulic oil from flowing back into the oil tank.

[0028] 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 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.

[0029] The above arrangement, through the arrangement of the first safety valve group, enables that when the first accumulator needs to be maintained, the hydraulic oil in the first accumulator can be drained back to the oil tank by opening the first safety ball valve, thereby facilitating maintenance of the first accumulator.

[0030] 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 relief valve and a second safety ball valve. The oil inlet end of the second safety relief valve is connected to the second accumulator, and the oil outlet end of the second safety relief 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.

[0031] 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 to drain the hydraulic oil in the second accumulator back to the oil tank, thereby facilitating maintenance of the second accumulator.

[0032] Furthermore, a pressure switch is provided between the first accumulator and the oil tank.

[0033] The above arrangement, through the setting 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.

[0034] Furthermore, a second pressure switch is provided between the second accumulator and the oil tank.

[0035] The above arrangement, through the setting 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.

[0036] 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.

[0037] The above setting, by setting up the third oil circuit, makes it possible that when the follower pulley stops working, the follower cylinder needs to retract the piston rod, and by controlling the reset reversing valve to obtain electrical reversal, 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.

[0038] Furthermore, the rodless end of the follower cylinder is also connected to the oil tank through an oil drain reversing valve, the P end of the oil drain reversing valve is connected to the rodless end of the follower cylinder, the T end of the oil drain reversing valve is connected to the oil tank, and the control end of the oil drain reversing valve is connected to the A end of the reset reversing valve.

[0039] With the above arrangement, when it is necessary to retract the piston rod of the servo cylinder, the servo control reversing valve is switched 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 servo cylinder; at this time, by controlling the reversing of the oil drain reversing valve, the P end of the oil drain reversing valve is connected to the T end. As a result, when the piston rod of the servo cylinder is retracted, the hydraulic oil can be pushed back to the oil tank through the oil drain reversing valve, so that the piston rod of the servo cylinder can be retracted into the cylinder body. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Schematic diagram of the hydraulic system of the present invention.

[0041] Figure 2 for Figure 1 Enlarged view of point C in the middle.

[0042] Figure 3 for Figure 1 Enlarged view of D in the middle.

[0043] Figure 4 This is a working principle diagram of the present invention. DETAILED DESCRIPTION

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] like Figure 1-Figure 3As shown, a servo compensation system includes a hydraulic control oil circuit and a servo cylinder 2, wherein the servo cylinder 2 is connected to a servo pulley (not shown in the figure), and the servo pulley is slidingly arranged on the boom of the crane (not shown in the figure). The servo pulley is connected to the servo hook through a servo cable and is connected to the lifting hook through a lifting cable (not shown in the figure). The hydraulic control oil circuit 1 includes a servo control reversing valve 11, a first logic valve 12, a second logic valve 13, a first accumulator 14 and a second accumulator 16. 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 servo cylinder 2; a servo control reversing valve 11 is provided on the second oil circuit 22, the P end of the servo control reversing valve 11 is connected to the second oil circuit 22, the T end of the servo control reversing valve 11 is connected to the oil tank 01, and the B end of the servo control reversing valve 11 is connected to the control ends of the first logic valve 12 and the second logic valve 13.

[0046] like Figure 3 As shown, a first control ball valve 141 is provided on the oil outlet end 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 on the oil outlet end of the second accumulator 16, and the second control ball valve 161 is in a normally open state.

[0047] The first and second accumulators 14 and 16 are also connected to the fuel tank 01. A one-way valve 011 is installed between the fuel tank 01 and the first and second accumulators 14 and 16. The oil inlet of the one-way valve 011 is connected to the fuel tank 01, and the oil outlet of the one-way valve 011 is connected to the first and second accumulators 14 and 16. Hydraulic oil is replenished from the fuel tank 01 to the first and second accumulators 14 and 16, ensuring timely replenishment of the hydraulic oil. The one-way valve 011 prevents the hydraulic oil from flowing back into the fuel tank 01. A pressure switch 012 is also installed between the first accumulator 14 and the fuel tank 01. This allows the pressure in the first accumulator 14 to be replenished when the hydraulic oil pressure is insufficient. A second pressure switch 013 is installed between the second accumulator 16 and the fuel 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.

[0048] like Figure 1 and Figure 3As shown, a first safety valve group 15 is further provided between the first accumulator 14 and the first and second oil circuits 21 and 22. The first safety valve group 15 includes a first safety relief valve 151 and a first safety ball valve 152. The oil inlet of the first safety relief valve 151 is connected to the first accumulator 14, and the oil outlet 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. The provision of the first safety valve group allows, if maintenance of the first accumulator 14 is required, the first safety ball valve 152 can be opened, thereby draining the hydraulic oil in the first accumulator 14 back to the oil tank 01, thereby facilitating maintenance of the first accumulator 14.

[0049] like Figure 1 and Figure 3 As shown, a second safety valve group 17 is further 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, and 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 configuration, through the configuration of the second safety valve group 17, allows, if maintenance of the second accumulator 16 is required, by opening the second safety ball valve 172, the hydraulic oil in the second accumulator 16 can be drained back to the oil tank 01, thereby facilitating maintenance of the second accumulator 16.

[0050] The rod end 24 of the follower cylinder 2 is connected to the oil tank 01 via a 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 of the oil tank 01, the T end of the reset reversing valve 26 is connected to the oil return 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 block is to stop working, the follower cylinder 2 needs to retract its piston rod. By controlling the reset reversing valve 26 to be energized and reversed, the P end of the reset reversing valve 26 is connected to the A end. As a result, hydraulic oil output from the oil tank 01 flows through the reset reversing valve 26 into the rod end of the follower cylinder 2, thereby driving the piston rod of the follower cylinder 2 to retract into the cylinder body of the follower cylinder 2.

[0051] The rodless end 23 of the slave cylinder 2 is also connected to the oil tank 01 via an oil drain reversing valve 27. The P end of the oil drain reversing valve 27 is connected to the rodless end 23 of the slave cylinder 2, the T end of the oil drain reversing valve 27 is connected to the oil tank, and the control end X of the oil drain reversing valve 27 is connected to the A end of the reset reversing valve 26. When the piston rod of the slave cylinder 2 needs to be retracted, the slave control reversing valve 11 is switched closed, causing the first logic valve 12 and the second logic valve 13 to close, and the first accumulator 14 is unable to deliver hydraulic oil to the rodless end of the slave cylinder 2. At this time, the oil drain reversing valve 27 is controlled to switch, connecting the P end of the oil drain reversing valve 27 to the T end. As a result, when the piston rod of the slave cylinder 2 retracts, the hydraulic oil is pushed back to the oil tank through the oil drain reversing valve 27, allowing the piston rod of the slave cylinder 2 to retract into the cylinder body.

[0052] like Figure 4 As shown, a working method of a servo compensation system includes the following steps:

[0053] (1) The crane drives the lifting hook through the cargo winch to lift the load.

[0054] (2) The follower hook is driven by a follower winch to connect to the supply ship.

[0055] (3) The follower block moves as the supply ship floats.

[0056] (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.

[0057] (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 servo control reversing valve 11, and the first logic valve 12 and the second logic valve 13 are opened.

[0058] (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 .

[0059] (7) When the supply ship sinks.

[0060] (71) The supply ship moves by pulling the follower block with the follower cable.

[0061] (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.

[0062] (73) The hydraulic oil in the rodless end 23 of the follower cylinder 2 is pushed through the first oil path 21 and the second oil path 22 to flow back to the first accumulator 14 and the second accumulator 16.

[0063] (8) When the supply ship surfaces.

[0064] (81) The tension in the follower cable between the supply ship and the follower block decreases.

[0065] (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.

[0066] (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.

[0067] (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.

[0068] (10) During the follow-up operation, if an accumulator fails.

[0069] (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.

[0070] (12) The other accumulator works normally and delivers hydraulic oil to the follower cylinder.

[0071] The working principle of the present invention is as follows: by connecting the follower cylinder 2 to the follower pulley, when the main ship wants to transport cargo between the supply ship and the main 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 on the 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 movement of the follower pulley drives 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 colliding with the ship, and driving the follower cylinder 2 to extend while the follower pulley moves with the supply ship. Retraction movement, at this time, the servo control reversing valve 11 is energized and reversed, so that the P end of the servo 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 servo 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 servo 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 servo pulley through the servo cable. The pressure of the servo pulley overcomes the outward thrust of the servo cylinder 2, so that the piston rod of the servo cylinder 2 is pushed inward and retracted, so that the hydraulic oil at the rodless end of the servo 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. When the follower block moves, it drives the lifting hook to move together, ensuring that a certain distance is always maintained between the cargo and the supply ship, avoiding the cargo and the supply ship In the event of an accidental collision, the safety of the lifting process is ensured; 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, during 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 hydraulic oil or output hydraulic oil, so that the other accumulator can continue to replenish oil to the follower cylinder normally, and the closure of the control ball valve can prevent the failed accumulator from absorbing the hydraulic oil in the oil circuit, thereby 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, the servo compensation system comprising a hydraulic control oil circuit, a servo cylinder, and an accumulator, the accumulator comprising a first accumulator and a second accumulator, the hydraulic control oil circuit comprising 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 being connected to one end of the first logic valve via a first oil circuit on one hand, and the first accumulator being connected to one end of the second logic valve via a second oil circuit on the other hand, and the other ends of the first logic valve and the second logic valve being connected to the rodless end of the servo cylinder; a servo control reversing valve being provided in the second oil circuit, the P end of the servo control reversing valve being connected to the second oil circuit, the T end of the servo control reversing valve being connected to the oil tank, and the B end of the servo control reversing valve being connected to the control ends of the first logic valve and the second logic valve; The control ball valve includes a first control ball valve and a second control ball valve. The first control ball valve is provided on the oil outlet end of the first accumulator and is in a normally open state. The second control ball valve is provided on the oil outlet end of the second accumulator and is in a normally open state. The characteristics are: The specific steps include: (1) The crane drives the lifting hook to lift the load through the cargo winch; (2) Connecting the follower hook to the supply ship through the follower winch; (3) The follower block moves with the floating of the supply ship; (4) The servo control reversing valve is electrically reversed, 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 servo 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 block with the follower cable; The pressure of the follower pulley's 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 through the first oil path and the second oil path to flow back to the first accumulator and the second accumulator; (8) When the supply ship surfaces; (81) The tension in the follower cable between the supply ship and the follower block decreases; (82) The oil pressure of the first accumulator and the second accumulator overcomes the pressure of the follower pulley, 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; (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; (9) As 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. The method for maintaining normal operation in an emergency 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.

3. The method for maintaining normal operation in an emergency according to claim 1, 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.

4. The method for maintaining normal operation in an emergency according to claim 1, 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 relief valve and a second safety ball valve. The oil inlet end of the second safety relief valve is connected to the second accumulator, and the oil outlet end of the second safety relief 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.

5. The method for maintaining normal operation in an emergency according to claim 1, characterized in that: A first pressure switch is further provided between the first accumulator and the oil tank.

6. The method for maintaining normal operation in an emergency according to claim 1, characterized in that: A second pressure switch is provided between the second accumulator and the oil tank.

7. The method for maintaining normal operation in an emergency 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.

8. The method for maintaining normal operation in an emergency according to claim 6, characterized in that: The rodless end of the follower cylinder is also connected to the oil tank through an oil drain reversing valve, the P end of the oil drain reversing valve is connected to the rodless end of the follower cylinder, the T end of the oil drain reversing valve is connected to the oil tank, and the control end of the oil drain reversing valve is connected to the A end of the reset reversing valve.

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