System high-low regulating valve oil motor quick closing actuator

Abstract

The utility model provides a kind of system high school low regulation valve oil motor quick closing actuator, it solves the valve path response under the problem of power failure state, it includes the oil cylinder of driving regulating valve, oil cylinder is connected with pressure oil circuit and oil return circuit by servo valve, still includes control oil circuit, first plug-in valve and second plug-in valve;The A mouth of first plug-in valve is connected to pressure oil circuit, its B mouth is connected to the lower cavity of oil cylinder, its C mouth is connected to control oil circuit;The A mouth of second plug-in valve is connected to the upper cavity of oil cylinder, its B mouth is connected to oil return circuit, its C mouth is connected to control oil circuit.The utility model has the advantages of high safety, stable operation etc..

Description

Technical Field

[0001] This utility model belongs to the field of hydraulic actuator control technology, specifically relating to a rapid shut-off actuator for a system high, medium and low temperature regulating valve hydraulic actuator. Background Technology

[0002] The turbine control valve, also known as the main steam valve or regulating steam valve, is a core control component of the turbine's steam intake system. Its main function is to precisely control the steam flow and pressure entering the turbine's high-pressure cylinder according to the grid load requirements, thereby regulating the turbine's output power and speed to ensure the safe, stable, and efficient operation of the unit. Existing turbine control valves need to close rapidly in emergency situations; if the turbine is not shut off in time, it can easily lead to damage to the valve itself, causing economic losses. The closing time of existing turbine control valves is mainly determined by the control valve's hydraulic actuator, which typically uses electromagnetic control. If the control system is completely de-energized, it cannot trigger emergency closure by switching valve circuits.

[0003] To address the shortcomings of existing technologies, people have conducted long-term explorations and proposed various solutions. For example, Chinese patent literature discloses a quick-closing valve oil actuator for steam turbines [201710132059.X], which includes an oil actuator, a control component, and a spring assembly. The spring assembly is located inside the oil actuator, and the control component is connected to the rod chamber of the oil actuator. The control component is equipped with an accumulator for recovering the oil inside the oil actuator.

[0004] The above solution has solved the problem of rapid shut-off of existing steam turbines to some extent, but it still has many shortcomings, such as valve response under power failure conditions. Summary of the Invention

[0005] The purpose of this invention is to address the above-mentioned problems by providing a reasonably designed and highly safe system for the rapid shut-off actuator of the high, medium, and low temperature regulating valve oil motor.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a system high, medium and low pressure regulating valve hydraulic actuator for rapid closing, comprising a hydraulic cylinder for driving the regulating valve, the hydraulic cylinder being connected to a pressure oil circuit and a return oil circuit via a servo valve, and further comprising a control oil circuit, a first cartridge valve and a second cartridge valve; the A port of the first cartridge valve is connected to the pressure oil circuit, its B port is connected to the lower chamber of the hydraulic cylinder, and its C port is connected to the control oil circuit; the A port of the second cartridge valve is connected to the upper chamber of the hydraulic cylinder, its B port is connected to the return oil circuit, and its C port is connected to the control oil circuit; When the control oil circuit is pressurized, the first cartridge valve and the second cartridge valve are closed, and the hydraulic actuator is controlled by the servo valve to operate normally. When the control oil circuit is depressurized, the first cartridge valve and the second cartridge valve are opened, forming a first high-flow channel from the pressure oil circuit through the first cartridge valve to the lower chamber of the cylinder and a second high-flow channel from the upper chamber of the cylinder through the second cartridge valve to the return oil circuit, driving the cylinder to close.

[0007] In the above-mentioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, the pressure at port C of the first cartridge valve and the second cartridge valve is equal, and the pressure-bearing area at port C of the first cartridge valve and the second cartridge valve is greater than the pressure-bearing area at port A.

[0008] In the aforementioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, the lower chamber of the cylinder receives pressurized oil to drive the piston rod to extend and close the regulating valve, while the upper chamber of the cylinder discharges oil when the regulating valve is closed.

[0009] In the aforementioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, the pressure oil circuit, return oil circuit and control oil circuit are respectively connected to shut-off valves.

[0010] In the aforementioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, a one-way valve is connected between the servo valve and the oil cylinder.

[0011] In the aforementioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, a filter element is installed in the pressure oil circuit between the first cartridge valve and the servo valve.

[0012] In the aforementioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, the hydraulic cylinder is equipped with a guide mechanism. The guide mechanism has a guide plate mounted on the hydraulic cylinder, and the guide plate has a guide groove extending in the vertical direction. The piston rod of the hydraulic cylinder has a guide block that is slidably connected to the guide groove.

[0013] In the aforementioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, the hydraulic cylinder is equipped with a displacement sensor, and an indicator scale is installed between the piston rod of the hydraulic cylinder and the guide plate.

[0014] In the above-mentioned system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator, the actuator is externally encapsulated with a protective cover.

[0015] In the aforementioned system's high, medium, and low temperature regulating valve hydraulic actuator quick-closing actuator, an integrated block is installed inside the protective cover.

[0016] Compared with existing technologies, the advantages of this invention are as follows: the diameter of the cartridge valve channel is much larger than that of the servo valve, which can instantly pass a huge oil flow to provide driving force for the oil cylinder, ensuring that the valve closes quickly and meets the requirements of emergency shutdown; the hydraulic circuit of the cartridge valve is set independently from that of the servo valve, and the valve circuit can be automatically switched in the power failure state to ensure the safety of the hydraulic motor; the use of an integrated block to integrate the servo valve, cartridge valve, check valve, etc. reduces the external pipeline connection, making the structure compact and reducing the number of leakage points. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the oil circuit of this utility model; Figure 3 This is a schematic diagram of the normal operation of this utility model; Figure 4 This is a schematic diagram of the emergency shutdown operation of this utility model; In the figure, there are: cylinder 1, guide plate 11, guide groove 12, guide block 13, displacement sensor 14, indicator scale 15, servo valve 2, protective cover 21, integrated block 22, pressure oil circuit 3, return oil circuit 4, control oil circuit 5, first cartridge valve 6, second cartridge valve 7, shut-off valve 8, and check valve 9. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1-4 As shown, a system of high, medium, and low pressure regulating valve hydraulic actuators for rapid closure is mainly used in industrial valve control, particularly in power plant turbine regulating systems, to ensure rapid and reliable closure of the regulating valve in emergency situations. The core components of this actuator include a hydraulic cylinder 1 that drives the regulating valve. The cylinder 1 is connected to a pressure oil circuit 3 and a return oil circuit 4 via a servo valve 2 to achieve precise flow control. In addition, it includes a control oil circuit 5, a first cartridge valve 6, and a second cartridge valve 7, which work together to achieve the rapid closure function.

[0020] In this design, port A of the first cartridge valve 6 is connected to the pressure oil circuit 3, port B is connected to the lower chamber of the cylinder 1, and port C is connected to the control oil circuit 5. Port A of the second cartridge valve 7 is connected to the upper chamber of the cylinder 1, port B is connected to the return oil circuit 4, and port C is also connected to the control oil circuit 5. This design ensures that when there is pressure in the control oil circuit 5, both the first and second cartridge valves 6 are closed. At this time, the hydraulic actuator is controlled by the servo valve 2 to operate normally, achieving precise adjustment of the valves. The servo valve 2, as an electro-hydraulic servo valve, can adjust the oil flow rate according to the input signal, thereby controlling the displacement and speed of the cylinder 1.

[0021] When the control oil circuit 5 loses pressure, such as in the event of a system failure or emergency shutdown, the first cartridge valve 6 and the second cartridge valve 7 quickly open, forming a first high-flow-rate channel from the pressure oil circuit 3 through the first cartridge valve 6 to the lower chamber of the cylinder 1, and a second high-flow-rate channel from the upper chamber of the cylinder 1 through the second cartridge valve 7 to the return oil circuit 4. These high-flow-rate channels allow high-pressure oil to quickly enter the lower chamber of the cylinder, while the oil in the upper chamber is rapidly discharged, thereby driving the piston rod of the cylinder 1 to extend rapidly, achieving emergency closure of the regulating valve, and significantly improving the system's response speed and reliability.

[0022] Specifically, the pressure at port C of the first cartridge valve 6 and the second cartridge valve 7 is equal, and they share the same control oil circuit 5, ensuring synchronous operation. In addition, the pressure-bearing area at port C of the first cartridge valve 6 and the second cartridge valve 7 is larger than that at port A. This area difference design makes it easier for the cartridge valves to open when the control oil circuit loses pressure, thereby reducing response time and improving the reliability of rapid closure.

[0023] In detail, the lower chamber of cylinder 1 receives pressurized oil to drive the piston rod to extend and close the regulating valve, while the upper chamber of cylinder 1 discharges oil when the regulating valve is closed. The piston rod of cylinder 1 is connected to the valve port of the piston rod through a lever structure, which further improves the opening and closing driving force.

[0024] Furthermore, the pressure oil circuit 3, the return oil circuit 4, and the control oil circuit 5 are each connected to a shut-off valve 8, which can be used to isolate the oil circuit, facilitate maintenance and testing, and prevent oil leakage.

[0025] Furthermore, a check valve 9 is connected between the servo valve 2 and the cylinder 1. The check valve 9 can be equipped with a corresponding pressure relief structure to ensure the internal pressure of the pressure oil circuit 3 and the return oil circuit 4 is stable.

[0026] In addition, a filter element 31 is installed on the pressure oil circuit 3 between the first cartridge valve 6 and the servo valve 2 to remove impurities in the oil, protect the servo valve 2 and the cartridge valve from contamination, and extend the life of the components.

[0027] Meanwhile, in order to ensure that the piston rod of the hydraulic cylinder 1 maintains linear motion during operation and reduce uneven wear and jamming, the hydraulic cylinder 1 is equipped with a guide mechanism. The guide mechanism has a guide plate 11 mounted on the hydraulic cylinder 1. The guide plate 11 has a guide groove 12 extending in the vertical direction. The piston rod of the hydraulic cylinder 1 has a guide block 13 that is slidably connected to the guide groove 12. This structure ensures that the piston rod moves in the vertical direction. The end of the piston rod is further connected to the regulating valve through a hinge structure.

[0028] As can be seen, the hydraulic cylinder 1 is equipped with a displacement sensor 14, preferably a linear variable differential transformer (LVDT) to monitor the displacement of the piston rod, and an indicator scale 15 is installed between the piston rod of the hydraulic cylinder 1 and the guide plate 11.

[0029] It is obvious that the actuator is externally enclosed by a protective cover 21, which is usually made of stainless steel, and the oil cylinder 1 is still located externally to ensure its normal heat dissipation.

[0030] Preferably, the protective cover 21 is provided with an integrated block 22, and the oil inlet and outlet are provided on the integrated block 22, which are connected to the internal pressure oil circuit 3, return oil circuit 4 and other oil circuits.

[0031] In summary, the principle of this embodiment is as follows: the control oil circuit 5 controls the first cartridge valve 6 and the second cartridge valve 7 in a coordinated manner. When the system is working normally, the servo valve 2 adjusts the cylinder 1 through precise electro-hydraulic signals. When the control oil circuit 5 loses pressure, the specific area ratio design of the C-port pressure-bearing area of ​​the first cartridge valve 6 and the second cartridge valve 7 being greater than the A-port pressure-bearing area allows the two cartridge valves to open rapidly under the action of spring force or residual pressure at the A-port. This instantly establishes a high-flow-rate drive channel that bypasses the servo valve 2 and directly injects pressurized oil into the lower chamber of the cylinder 1 through the first cartridge valve 6 via the pressure oil circuit 3, as well as another high-flow-rate pressure relief channel that quickly discharges oil from the upper chamber of the cylinder 1 through the second cartridge valve 7 to the return oil circuit 4. Ultimately, this achieves the rapid extension of the hydraulic actuator piston rod and the emergency closure of the regulating valve.

[0032] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

[0033] Although this document frequently uses terms such as cylinder 1, guide plate 11, guide groove 12, guide block 13, displacement sensor 14, indicating scale 15, servo valve 2, protective cover 21, integrated block 22, pressure oil circuit 3, return oil circuit 4, control oil circuit 5, first cartridge valve 6, second cartridge valve 7, shut-off valve 8, and check valve 9, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of this utility model; interpreting them as any additional limitation would contradict the spirit of this utility model.

Claims

1. A system high, medium, and low pressure regulating valve hydraulic actuator for rapid closing, comprising a hydraulic cylinder (1) for driving the regulating valve, wherein the hydraulic cylinder (1) is connected to a pressure oil circuit (3) and a return oil circuit (4) via a servo valve (2), characterized in that, It also includes a control oil circuit (5), a first cartridge valve (6) and a second cartridge valve (7); the first cartridge valve (6) has its A port connected to the pressure oil circuit (3), its B port connected to the lower chamber of the cylinder (1), and its C port connected to the control oil circuit (5); the second cartridge valve (7) has its A port connected to the upper chamber of the cylinder (1), its B port connected to the return oil circuit (4), and its C port connected to the control oil circuit (5); When the control oil circuit (5) is pressurized, the first cartridge valve (6) and the second cartridge valve (7) are closed, and the hydraulic motor is controlled by the servo valve (2) to work normally; when the control oil circuit (5) is depressurized, the first cartridge valve (6) and the second cartridge valve (7) are opened, forming a first high-flow channel from the pressure oil circuit (3) through the first cartridge valve (6) to the lower chamber of the cylinder (1) and a second high-flow channel from the upper chamber of the cylinder (1) through the second cartridge valve (7) to the return oil circuit (4), driving the cylinder (1) to close.

2. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, The pressure at port C of the first cartridge valve (6) and the second cartridge valve (7) is equal, and the pressure-bearing area at port C of the first cartridge valve (6) and the second cartridge valve (7) is greater than the pressure-bearing area at port A.

3. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, The lower chamber of the oil cylinder (1) receives pressurized oil to drive the piston rod to extend and close the regulating valve, while the upper chamber of the oil cylinder (1) discharges oil when the regulating valve is closed.

4. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, The pressure oil circuit (3), return oil circuit (4) and control oil circuit (5) are respectively connected to shut-off valves (8).

5. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, A check valve (9) is connected between the servo valve (2) and the oil cylinder (1).

6. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, The pressure oil circuit (3) is equipped with a filter element (31) located between the first cartridge valve (6) and the servo valve (2).

7. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, The cylinder (1) is equipped with a guide mechanism, which has a guide plate (11) mounted on the cylinder (1), the guide plate (11) has a guide groove (12) extending in the vertical direction, and the piston rod of the cylinder (1) has a guide block (13) that is slidably connected to the guide groove (12).

8. The system high, medium and low pressure regulating valve hydraulic actuator quick-closing actuator according to claim 7, characterized in that, The cylinder (1) is equipped with a displacement sensor (14), and an indicator scale (15) is installed between the piston rod of the cylinder (1) and the guide plate (11).

9. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 1, characterized in that, The actuator is externally encapsulated with a protective cover (21).

10. The system high, medium and low temperature regulating valve hydraulic actuator quick-closing actuator according to claim 9, characterized in that, An integrated block (22) is provided inside the protective cover (21).

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