A hydraulic control system for a single-outlet double-acting actuator

Abstract

The application discloses a hydraulic control system of a single-out-rod double-acting actuator, which comprises a main control valve, an oil supply oil path, a return oil path, a safety quick-opening loop, a shuttle valve group, a solenoid valve group and a hydraulic control valve group.

Description

Technical Field

[0001] This invention relates to the field of fluid pressure actuator technology, and in particular to a hydraulic control system for a single-rod double-acting actuator. Background Technology

[0002] In industries such as petrochemicals, coal chemicals, and power, emergency shut-off valves in key process pipelines typically employ hydraulic actuators driven by single-rod double-acting cylinders to achieve both regular valve opening adjustment and safe, rapid opening in emergency situations.

[0003] Currently, the hydraulic control system of double-acting actuators is generally implemented by a control loop formed by control valve assemblies. A safety quick-opening circuit within this control loop ensures safe and rapid valve opening. However, existing safety quick-opening circuits typically use a single solenoid valve for logic control, making them susceptible to electromagnetic interference and signal failures, leading to malfunctions or failures to operate, resulting in low operational stability. Furthermore, the safety quick-opening circuit is usually coupled with the return oil path of the control loop. When the control valve in the control loop malfunctions, the return oil path of the safety quick-opening circuit is easily blocked, failing to guarantee reliable quick opening in emergency situations. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a hydraulic control system for a single-rod double-acting actuator, which avoids single-point electromagnetic interference, prevents false triggering due to signal failures, and ensures that the system never fails to operate, thereby improving the stability of system operation.

[0005] This invention is achieved through the following technical solution:

[0006] This invention provides a hydraulic control system for a single-rod double-acting actuator. The single-rod double-acting actuator includes a base. The interior of the base has a rodless chamber and a rod chamber formed with a piston as the boundary. The cross-sectional area of ​​the rod chamber is smaller than that of the rodless chamber. A spring is provided inside the base on one side corresponding to the rod chamber. One end of the spring abuts against the end face of the piston, and the other end abuts against the base.

[0007] The hydraulic control system of the single-acting double-rod actuator includes:

[0008] The main control valve has its port A connected to the rodless chamber;

[0009] The oil supply circuit includes a first oil supply branch and a second oil supply branch that are interconnected. The first oil supply branch is connected to the rod chamber, and the second oil supply branch is connected to the oil inlet P of the main control valve.

[0010] The return oil circuit is connected to the return port T of the main control valve;

[0011] A safety quick-opening circuit includes a hydraulic control valve group, a shuttle valve group, and a solenoid valve group. The hydraulic control valve group includes three hydraulic control valves arranged in parallel. The inlet of each hydraulic control valve is connected to the rodless chamber, and the outlet is connected to the return oil circuit. The shuttle valve group includes three shuttle valves. The outlet of each shuttle valve is connected to the control oil chamber of each hydraulic control valve. The solenoid valve group includes three solenoid valves. The inlet P of each solenoid valve is connected to the second oil supply branch, and the return oil T of each solenoid valve is connected to the return oil circuit. The outlet A of each solenoid valve is connected to one inlet of any two different shuttle valves, and each inlet of each shuttle valve is connected to only one solenoid valve.

[0012] Furthermore, the main control valve is a three-position four-way proportional solenoid valve.

[0013] Furthermore, the hydraulic control valve is a two-position two-way hydraulic control valve. In the normal position, the oil inlet and oil outlet of each hydraulic control valve are disconnected.

[0014] Furthermore, the shuttle valve assembly includes a first shuttle valve, a second shuttle valve, and a third shuttle valve;

[0015] The solenoid valve group includes a first solenoid valve, a second solenoid valve, and a third solenoid valve.

[0016] The oil inlet P of the first solenoid valve is connected to the second oil supply branch, the oil port A of the first solenoid valve is connected to the first inlet of the first shuttle valve and the first inlet of the second shuttle valve, and the oil return port T of the first solenoid valve is connected to the oil return circuit.

[0017] The oil inlet P of the second solenoid valve is connected to the second oil supply branch, the oil port A of the second solenoid valve is connected to the second inlet of the first shuttle valve and the first inlet of the third shuttle valve, and the oil return port T of the second solenoid valve is connected to the oil return circuit.

[0018] The oil inlet P of the third solenoid valve is connected to the second oil supply branch, the oil port A of the third solenoid valve is connected to the second inlet of the second shuttle valve and the second inlet of the third shuttle valve, and the oil return port T of the third solenoid valve is connected to the oil return circuit.

[0019] Furthermore, the first solenoid valve, the second solenoid valve, and the third solenoid valve are two-position three-way solenoid valves.

[0020] In the normal position, the first solenoid valve, the second solenoid valve, and the third solenoid valve are energized, causing the corresponding oil inlet P and oil outlet A to be connected; this causes oil pressure at the oil outlets of the corresponding first shuttle valve, second shuttle valve, and third shuttle valve, thereby controlling the corresponding hydraulic control valve to disconnect.

[0021] Furthermore, in the aforementioned safety quick-opening circuit,

[0022] A first throttle valve is connected in series between the oil inlet of the three hydraulic control valves and the rodless chamber. The first throttle valve is an adjustable flow valve.

[0023] Furthermore, in the aforementioned safety quick-opening circuit,

[0024] A second throttle valve is connected in series between the oil inlet of the three hydraulic valves and the rodless chamber, and the second throttle valve is connected in parallel with the first throttle valve.

[0025] Furthermore, the second throttle valve is a fixed throttle valve.

[0026] Furthermore, a third throttle valve is also provided on the second oil supply branch, and the third throttle valve is a fixed throttle valve.

[0027] Furthermore, a spring receiving cavity is formed around the periphery of the rod cavity for accommodating the spring;

[0028] The hydraulic control system also includes an oil leakage recovery circuit, one end of which is connected to the spring receiving cavity and the other end of which is connected to the return oil circuit.

[0029] Compared with the prior art, the advantages of this invention are:

[0030] The hydraulic control system of the single-rod double-acting actuator in this invention embodiment includes a hydraulic control valve group, a shuttle valve group, and a solenoid valve group in the safety quick-opening circuit. The hydraulic control valve group includes three hydraulic control valves connected in parallel, each with its inlet connected to the rodless chamber and its outlet connected to the return oil circuit. The shuttle valve group includes three shuttle valves, each with its outlet connected to the control oil chamber of a corresponding hydraulic control valve. The solenoid valve group includes at least three solenoid valves, each with its inlet P connected to the second oil supply branch, its return port T connected to the return oil circuit, and its port A connected to one inlet of any two different shuttle valves, with each inlet of each shuttle valve connected to only one solenoid valve. Therefore, only when any two or more of the three solenoid valves are de-energized can at least one of the three shuttle valves depressurize and open one of the corresponding hydraulic control valves, thereby draining the rodless chamber and causing the piston to move rapidly upwards, driving the piston rod to safely and quickly open the valve. This design avoids single-point electromagnetic interference and prevents false triggering due to signal failure. Furthermore, the three hydraulic control valves are connected in parallel, so if any one valve fails, the other two can still release oil and will never fail to operate. This synergistically improves the stability of the system operation. Attached Figure Description

[0031] Figure 1This is a schematic diagram of the hydraulic control system of a single-rod double-acting actuator according to an embodiment of the present invention.

[0032] Figure label:

[0033] 100. Single-acting double-rod actuator; 110. Piston; 120. Rodless chamber; 130. Rod chamber; 140. Spring receiving chamber; 150. Spring; 10. Main control valve; 20. Oil supply circuit; 21. First oil supply branch; 22. Second oil supply branch; 221. Third throttle valve; 30. Oil return circuit; 40. Safety quick-opening circuit; 41. First hydraulic control valve; 42. Second hydraulic control valve; 43. Third hydraulic control valve; 44. First shuttle valve; 45. Second shuttle valve; 46. Third shuttle valve; 47. First solenoid valve; 48. Second solenoid valve; 49. Third solenoid valve; 401. First throttle valve; 402. Second throttle valve; 50. Leakage recovery circuit. Detailed Implementation

[0034] The following detailed, non-limiting description of the invention's technical solutions, in conjunction with preferred embodiments and accompanying drawings, is provided. In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0035] First, the single-acting double-rod actuator of an embodiment of the present invention will be introduced. For example... Figure 1 As shown, the single-rod double-acting actuator 100 may include a base. Inside the base, a rodless chamber 120 and a rod chamber 130 are formed with the piston 110 as the boundary. The cross-sectional area of ​​the rod chamber 130 is smaller than that of the rodless chamber 120. A spring 150 is provided inside the base, corresponding to one side of the rod chamber 130. One end of the spring 150 abuts against the end face of the piston 110, and the other end abuts against the base. A spring receiving cavity 140 is formed around the rod chamber 130 to accommodate the spring 150.

[0036] Specifically, when the single-rod double-acting actuator 100 is in the forward drive mode, i.e., pressurized fluid (e.g., oil) enters the rodless chamber 120, the pressure acts on the entire cross-section of the upper side of the piston 110 and generates thrust. The thrust overcomes the preload of the spring 150 and pushes the piston 110 downward, causing the piston rod to extend (at this time, the piston rod drives the valve body to close). The fluid in the rod chamber 130 is compressed and discharged, and the spring 150 is compressed, storing elastic potential energy. When the single-rod double-acting actuator 100 is in the reverse reset mode, i.e., pressurized fluid enters the rod chamber 130, the pressure acts on the lower side of the piston 110, and at the same time, the spring 150 releases elastic potential energy, assisting in pushing the piston 110 upward. Simultaneously, the YV5 of the main control valve 10 is energized, the rodless chamber 120 is depressurized, the piston rod retracts (at this time, the piston rod drives the valve body to open), the fluid in the rodless chamber 120 is discharged through the main control valve 10, and the piston 110 returns to its initial position, completing the reset.

[0037] The hydraulic control system of the single-rod double-acting actuator according to an embodiment of the present invention is described below.

[0038] like Figure 1 As shown, the hydraulic control system of the single-rod double-acting actuator of this embodiment of the invention may include a main control valve 10, an oil supply circuit 20, an oil return circuit 30, and a safety quick-opening circuit 40. The main control valve 10 is a three-position four-way proportional solenoid valve, specifically including an inlet port P, an outlet port T, an outlet A, and an outlet B. Outlet A is connected to the rodless chamber 120, and outlet B is in a blocked state. The main control valve 10 is not energized in its normal position, ensuring that its inlet port P, outlet port T, outlet A, and outlet B are not interconnected.

[0039] The oil supply circuit 20 may include a first oil supply branch 21 and a second oil supply branch 22 that are interconnected. The first oil supply branch 21 is connected to the rod chamber 130, the second oil supply branch 22 is connected to the oil inlet P of the main control valve 10, and the return oil circuit 30 is connected to the return oil port T of the main control valve 10.

[0040] The safety quick-opening circuit 40 may include a hydraulic control valve group, a shuttle valve group, and a solenoid valve group. The hydraulic control valve group includes three hydraulic control valves arranged in parallel. The hydraulic control valves are selected as two-position two-way hydraulic control valves. As an example, the hydraulic control valve group includes a first hydraulic control valve 41, a second hydraulic control valve 42, and a third hydraulic control valve 43 arranged in parallel. In the normal position, the oil inlet and oil outlet of each hydraulic control valve are disconnected. The oil inlet of each hydraulic control valve is connected to the rodless chamber 120, and the oil outlet is connected to the return oil circuit 30.

[0041] The shuttle valve assembly includes three shuttle valves, each with its outlet connected to the control oil chamber of a hydraulic valve. As an example, the shuttle valve assembly may include a first shuttle valve 44, a second shuttle valve 45, and a third shuttle valve 46 arranged in parallel.

[0042] The solenoid valve assembly includes three solenoid valves. The oil inlet P of each solenoid valve is connected to the second oil supply branch 22, and the oil return port T of each solenoid valve is connected to the return oil line 30. The oil port A of each solenoid valve is connected to one oil inlet of any two different shuttle valves, and each oil inlet of each shuttle valve is connected to only one solenoid valve.

[0043] As an example, the solenoid valve assembly may include a first solenoid valve 47, a second solenoid valve 48, and a third solenoid valve 49 arranged in parallel. The inlet P of the first solenoid valve 47 is connected to the second oil supply branch 22, the outlet A of the first solenoid valve 47 is connected to the first inlet of the first shuttle valve 44 and the first inlet of the second shuttle valve 45, and the return outlet T of the first solenoid valve 47 is connected to the return oil passage 30. The inlet P of the second solenoid valve 48 is connected to the second oil supply branch 22, the outlet A of the second solenoid valve 48 is connected to the second inlet of the first shuttle valve 44 and the first inlet of the third shuttle valve 46, and the return outlet T of the second solenoid valve 48 is connected to the return oil passage 30. The inlet P of the third solenoid valve 49 is connected to the second oil supply branch 22, the outlet A of the third solenoid valve 49 is connected to the second inlet of the second shuttle valve 45 and the second inlet of the third shuttle valve 46, and the return outlet T of the third solenoid valve 49 is connected to the return oil passage 30.

[0044] It should be noted that the first solenoid valve 47, the second solenoid valve 48, and the third solenoid valve 49 are two-position three-way solenoid valves. In their normal position, the first solenoid valve 47, the second solenoid valve 48, and the third solenoid valve 49 are energized, which makes their corresponding oil inlet P and oil outlet A open; thus, the corresponding first shuttle valve 44, the second shuttle valve 45, and the third shuttle valve 46 have oil pressure, thereby controlling the corresponding hydraulic control valves to disconnect, that is, controlling the first hydraulic control valve 41, the second hydraulic control valve 42, and the third hydraulic control valve 43 to disconnect.

[0045] Specifically, in the hydraulic control system of the single-rod double-acting actuator of the present invention, under normal conditions, since the main control valve 10 is a three-position four-way proportional solenoid valve (which can realize proportional adjustment of opening), it is not energized in the normal position. The oil inlet P, oil return T, oil port A and oil port B of the main control valve 10 are not connected to each other, and the piston 110 in the double-acting actuator 100 remains in the current position. When the YV4 electromagnet in the main control valve 10 is energized and reversed, the pressurized oil in the oil supply circuit 20 enters the inlet P of the main control valve 10 through the second oil supply branch 22, and then enters the rodless chamber 120 through the oil port A. Meanwhile, the rod chamber 130 is continuously supplied with oil through the first oil supply branch 21. Since the rodless chamber 120 and the rod chamber 130 share the same hydraulic source (i.e., the pressure is the same), but there is a difference in cross-sectional area between them (the cross-sectional area of ​​the rodless chamber 120 is larger than that of the rod chamber 130), the piston 110 facing the rodless chamber 120 experiences greater pressure. This pressure drives the piston 110 in the double-acting actuator 100 to move downwards against the preload of the spring 150, and extends the piston rod to close the valve. Conversely, when the YV5 electromagnet is energized, oil returns from the rodless chamber 120, and the pressure in the rod chamber 130 pushes the piston 110 back, causing the piston rod to retract and open the valve.

[0046] When the piston rod is extended and retracted normally, the oil inlet and outlet of the first hydraulic control valve 41, the second hydraulic control valve 42, and the third hydraulic control valve 43 are disconnected, so that the safety quick-opening circuit 40 is closed and does not interfere with normal regulation.

[0047] In an emergency, at least two or more of the first solenoid valve 47, the second solenoid valve 48, and the third solenoid valve 49 must be de-energized to allow at least one of the first shuttle valve 44, the second shuttle valve 45, and the third shuttle valve 46 to depressurize, and at least one of the hydraulic control valves to lose control oil. The hydraulic control valve that loses control oil will become open (at least one of the first hydraulic control valve 41, the second hydraulic control valve 42, and the third hydraulic control valve 43), allowing oil to drain from the rodless chamber 120. This causes the piston 110 to move rapidly upward, enabling the piston rod to safely and quickly open the valve. This design avoids single-point electromagnetic interference and prevents false triggering due to signal failure. Furthermore, the above situation will also be triggered if any two or more of the first solenoid valve 47, the second solenoid valve 48, and the third solenoid valve 49 are not supplied with pressurized oil. Moreover, the first hydraulic control valve 41, the second hydraulic control valve 42, and the third hydraulic control valve 43 are configured in parallel; if any one fails, the other two can still drain oil, ensuring continuous operation. This synergistic design improves the stability of the system operation.

[0048] It should be noted that the safety quick-opening circuit in this embodiment shares the oil return path of the control circuit, and the controls are independent and do not affect each other, which can ensure reliable quick opening in emergency conditions.

[0049] It should be noted that the main control valve 10 is a three-position four-way proportional solenoid valve. By controlling the energization of solenoid YV4, the valve core opening is increased, the oil flow is increased, and thus the valve closes quickly. Similarly, by controlling the energization of solenoid YV5, the return port T opening is larger, and the rodless chamber 120 flows out through the return port T of the main control valve 10, achieving quick opening.

[0050] In some embodiments, such as Figure 1 As shown, in the safety quick-opening circuit 40, a first throttle valve 401 is connected in series between the oil inlets of the three hydraulic control valves and the rodless chamber 120. Preferably, the first throttle valve 401 is an adjustable flow valve. A second throttle valve 402 is also connected in series between the oil inlets of the three hydraulic control valves and the rodless chamber 120. The second throttle valve 402 is connected in parallel with the first throttle valve 401. Preferably, the second throttle valve 402 is a fixed throttle valve.

[0051] In other words, an adjustable flow valve and a fixed throttle valve are connected in parallel between the interface of the rodless chamber 120 and the safety quick-opening circuit 40. The first throttle valve 401 is an adjustable flow valve, which can continuously adjust the flow area according to the on-site working conditions, load size, and actuator response speed requirements, precisely controlling the pressure relief rate of the rodless chamber 120, and avoiding mechanical shock, pipeline vibration, or valve water hammer caused by excessively rapid opening. The second throttle valve 402 is a fixed throttle valve, connected in parallel with the first throttle valve 401, forming a fixed minimum flow cross section. Even if the adjustable flow valve is manually closed, blocked, or malfunctions, the fixed throttle valve can still ensure that the pressure relief channel is unobstructed, ensuring that the actuator can open quickly in an emergency, structurally eliminating the risk of "safety circuit failure" and meeting a high safety level.

[0052] In some embodiments, such as Figure 1 As shown, a third throttle valve 221 is also provided on the second oil supply branch 22. The third throttle valve 221 is a fixed throttle valve.

[0053] Specifically, the third throttle valve 221 is a fixed throttle valve connected in series on the second oil supply branch 22 to throttle and stabilize the pressure oil entering the oil inlet P of the main control valve 10, preventing oil supply pressure fluctuations and instantaneous impacts from directly acting on the main valve, so that the main control valve 10 works under a stable and smooth control pressure, thereby improving the proportional control accuracy and consistency of action.

[0054] In some embodiments, such as Figure 1 As shown, it also includes an oil leakage recovery circuit 50, one end of which is connected to the spring receiving cavity 140, and the other end is connected to the return oil circuit 30.

[0055] Specifically, the spring receiving cavity 140 is a sealed chamber. After the actuator has been working for a long time, a small amount of internal leakage oil from the rod cavity 130 will enter the spring receiving cavity 140. The oil leakage recovery circuit 50 is directly connected to the return oil circuit 30, which can continuously guide the leaked oil back to prevent the pressure inside the spring receiving cavity 140 from rising and avoid increasing the resistance of the piston 110 movement and causing it to jam.

[0056] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A hydraulic control system for a single-rod double-acting actuator (100), the single-rod double-acting actuator (100) includes a base, the interior of the base having a rodless chamber (120) and a rod chamber (130) respectively formed with a piston (110) as the boundary, the cross-sectional area of ​​the rod chamber (130) being smaller than the cross-sectional area of ​​the rodless chamber (120); a spring (150) is provided inside the base and on one side corresponding to the rod chamber (130), one end of the spring (150) abutting the end face of the piston (110), and the other end abutting the base; Its features are, The hydraulic control system of the single-acting double-rod actuator includes: The main control valve (10) has its port A connected to the rodless chamber (120). Oil supply circuit (20), the oil supply circuit (20) includes a first oil supply branch (21) and a second oil supply branch (22) that are interconnected. The first oil supply branch (21) is connected to the rod chamber (130), and the second oil supply branch (22) is connected to the oil inlet P of the main control valve (10). Return oil passage (30), the return oil passage (30) is connected to the return oil port T of the main control valve (10); The safety quick-opening circuit (40) includes a hydraulic control valve group, a shuttle valve group, and a solenoid valve group. The hydraulic control valve group includes three hydraulic control valves arranged in parallel. The oil inlet of each hydraulic control valve is connected to the rodless chamber (120), and the oil outlet is connected to the return oil circuit (30). The shuttle valve group includes three shuttle valves. The oil outlet of each shuttle valve is connected to the control oil chamber of each hydraulic control valve. The solenoid valve group includes three solenoid valves. The oil inlet P of each solenoid valve is connected to the second oil supply branch (22), and the oil outlet T of each solenoid valve is connected to the return oil circuit (30). The oil outlet A of each solenoid valve is connected to one oil inlet of any two different shuttle valves, and each oil inlet of each shuttle valve is connected to only one solenoid valve.

2. The hydraulic control system of the single-acting double-acting actuator according to claim 1, characterized in that, The main control valve (10) is a three-position four-way proportional solenoid valve.

3. The hydraulic control system of the single-acting double-acting actuator according to claim 1, characterized in that, The hydraulic control valve is a two-position two-way hydraulic control valve. In the normal position, the oil inlet and oil outlet of each hydraulic control valve are disconnected.

4. The hydraulic control system of the single-acting double-acting actuator according to claim 1, characterized in that, The shuttle valve assembly includes a first shuttle valve (44), a second shuttle valve (45), and a third shuttle valve (46). The solenoid valve assembly includes a first solenoid valve (47), a second solenoid valve (48), and a third solenoid valve (49). The oil inlet P of the first solenoid valve (47) is connected to the second oil supply branch (22), the oil port A of the first solenoid valve (47) is connected to the first inlet of the first shuttle valve (44) and the first inlet of the second shuttle valve (45), and the oil return port T of the first solenoid valve (47) is connected to the oil return circuit (30). The oil inlet P of the second solenoid valve (48) is connected to the second oil supply branch (22), the oil port A of the second solenoid valve (48) is connected to the second inlet of the first shuttle valve (44) and the first inlet of the third shuttle valve (46), and the oil return port T of the second solenoid valve (48) is connected to the oil return circuit (30). The oil inlet P of the third solenoid valve (49) is connected to the second oil supply branch (22), the oil port A of the third solenoid valve (49) is connected to the second inlet of the second shuttle valve (45) and the second inlet of the third shuttle valve (46), and the oil return port T of the third solenoid valve (49) is connected to the oil return circuit (30).

5. The hydraulic control system of the single-acting double-acting actuator according to claim 4, characterized in that, The first solenoid valve (47), the second solenoid valve (48), and the third solenoid valve (49) are two-position three-way solenoid valves. In the normal position state, the first solenoid valve (47), the second solenoid valve (48) and the third solenoid valve (49) are energized, so that the corresponding oil inlet P and oil outlet A are connected; so that the corresponding first shuttle valve (44), second shuttle valve (45) and third shuttle valve (46) have oil pressure at their outlets, thereby controlling the corresponding hydraulic control valve to disconnect.

6. The hydraulic control system for the single-acting double-acting actuator according to claim 1, characterized in that, In the aforementioned safety quick-opening circuit (40), A first throttle valve (401) is connected in series between the oil inlet of the three hydraulic control valves and the rodless chamber (120). The first throttle valve (401) is an adjustable flow valve.

7. The hydraulic control system of the single-acting double-acting actuator according to claim 6, characterized in that, In the aforementioned safety quick-opening circuit (40), A second throttle valve (402) is connected in series between the oil inlet of the three hydraulic valves and the rodless chamber (120), and the second throttle valve (402) is connected in parallel with the first throttle valve (401).

8. The hydraulic control system of the single-acting double-acting actuator according to claim 7, characterized in that, The second throttle valve (402) is a fixed throttle valve.

9. The hydraulic control system of the single-acting double-acting actuator according to claim 1, characterized in that, The second oil supply branch (22) is also provided with a third throttle valve (221), which is a fixed throttle valve.

10. The hydraulic control system of the single-acting double-acting actuator according to claim 1, characterized in that, The periphery of the rod cavity (130) is formed with a spring receiving cavity (140) for accommodating the spring (150). The hydraulic control system also includes an oil leakage recovery circuit (50), one end of which is connected to the spring receiving cavity (140), and the other end is connected to the return oil circuit (30).

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