Novel valve adjusting hydraulic actuating mechanism

Abstract

The utility model discloses a novel valve adjusting hydraulic actuating mechanism, and relates to the technical field of steam turbines. Comprising a steam generator, a first connector, a connecting pipe, a first screw, a bent lever, an ejector pin, an upper cover body, an upper spring seat, a spring body, a lower spring seat, a valve element, a throttling valve, a shell, a sleeve, a gasket, a first flange, a second screw, an electromagnetic valve, a pipe connector, a second flange, a first cylindrical pin, a connecting plate, a feedback plate, a pull rod, a guide rail, a guide rod, a special pin, a frame, a bearing, a guide plate and a special screw. According to the novel valve adjusting hydraulic actuating mechanism, the servo amplifying device is arranged on the single-side oil inlet hydraulic servo-motor, the problem that a steam turbine adjusting steam valve cannot be normally closed under the condition that oil pressure of the actuating mechanism is lost can be solved, the problem of back pressure of the oil return side of the hydraulic actuating mechanism can be solved, and meanwhile power consumption is reduced; when the steam turbine is overspeed, an oil way can be effectively cut off, oil pressure is relieved, and safe operation of equipment is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steam turbines, in particular to a new valve adjusting hydraulic actuator. BACKGROUND

[0002] The steam turbine regulating valve controls the opening degree and emergency shutdown through an actuator. The steam turbine adjusts the steam flow of the regulating valve in real time according to the load during operation, thereby controlling the power generation or load size of the steam turbine. Therefore, the accuracy and speed of the regulating valve are required to be very high. At present, the main actuator on the market includes a hydraulic actuator, a servo pump controlled actuator, an electric actuator and a pneumatic actuator. The most widely used actuator on the market is the hydraulic actuator. The hydraulic actuator is divided into high pressure hydraulic actuator and low pressure hydraulic actuator according to the working pressure. The high pressure hydraulic actuator needs an independent oil source, and the oil quality requirement is very high, which is difficult to use and maintain. Therefore, many customers tend to use low pressure hydraulic actuators with stronger anti-pollution ability. The traditional low pressure hydraulic actuator has a large oil cylinder in order to meet the lifting force requirement because the oil pressure is 0.8-2 MPa. In order to achieve control speed and accuracy, the valve needs to quickly output a large amount of hydraulic oil to control the oil cylinder after a given signal is received, so as to control the steam turbine regulating valve. The mainstream product on the market is the oil motor introduced by Hangzhou Steam Turbine Co., Ltd. from Germany Siemens technology. The oil motor runs stably, but has the following defects: in the case of oil pressure loss, the regulating valve cannot be closed; because of the double-sided oil inlet, the oil return and oil measurement during regulation or closing are achieved by the oil pressure of the other side, so the output of the actuator is reduced. Therefore, in order to achieve the output ratio, the oil cylinder must be enlarged. Because the response speed of the regulating valve to the actuator is required to be very high, the servo amplifier device also needs to be increased after the oil cylinder is enlarged, the overall power consumption of the system is increased, and the cost of the pipeline and lubricating oil station is greatly increased after the pipeline and lubricating oil station are enlarged. There is no overspeed protection function. When the speed of the steam turbine exceeds 103% of the rated speed, the oil motor needs to quickly move to the closing direction to ensure that the speed quickly decreases to the rated speed.

[0003] In summary, the following are the disadvantages of the prior art:

[0004] 1. In the case of oil pressure loss due to failure of the oil supply system or pipeline leakage, the regulating valve cannot be closed.

[0005] 2. Double-sided oil inlet, high power consumption.

[0006] 3. Double-sided oil inlet affects the output. In order to meet the requirements, the oil cylinder and the servo amplifier device need to be increased, thereby increasing the pipeline and the lubricating oil station, and the cost is large.

[0007] There is no overspeed protection function. When the equipment overspeeds, it cannot be controlled in time, the equipment continues to speed up, the stop protection is triggered, the equipment is stopped, and the production is affected. SUMMARY

[0008] In view of the deficiencies of the prior art, the present application provides a new valve regulating hydraulic actuator, which solves the problems raised in the background art.

[0009] To achieve the above object, the present application is implemented by the following technical scheme: A new valve regulating hydraulic actuator, comprising a steam generator, a first connector, a connecting pipe, a first screw, a bent lever, a thimble, an upper cover body, an upper spring seat, a spring body, a lower spring seat, a valve core, a throttle valve, a shell, a sleeve, a gasket, a first flange, a second screw, a solenoid valve, a pipe connector, a second flange, a first cylindrical pin, a connecting plate, a feedback plate, a pull rod, a guide rail, a guide rod, a special pin, a frame, a bearing, a guide plate, a special screw, a displacement sensor, a bracket, a guide sleeve, a guide ring, a cylinder cover, a piston rod, a cylinder barrel, a piston block, a piston ring, a slotted nut, a second cylindrical pin, a cylinder lower cover, a cover plate, a connecting body, a hexagonal bolt, an internal hexagonal screw and an exhaust pipe, the bottom of the steam generator is threadedly connected with the first connector, the bottom of the first connector is threadedly connected with the connecting pipe, the connecting pipe is threadedly connected with the upper cover body, the bent lever is internally threadedly connected with the first screw, the thimble is in spherical contact with the upper spring seat, the first screw is in spherical contact with the thimble, the sleeve and the shell are fixed by a riding seam screw, the gasket and the first flange are fixed on the shell by the second screw, the solenoid valve, the second flange and the cover plate are all fixed on the shell by screws, the connecting body connects the shell with the cylinder cover and the cylinder lower cover by the hexagonal bolt and the internal hexagonal screw, the connecting plate and the feedback plate are connected by the first cylindrical pin, the guide rod is installed in the hole of the feedback plate by glue, the connecting plate and the pull rod are fixed by the cylindrical pin, the pull rod and the piston rod are threadedly connected, and the slotted nut is connected with the piston rod by the second cylindrical pin.

[0010] Optionally, the exhaust pipe is threadedly connected to the cylinder cover and the cylinder lower cover by the pipe connector.

[0011] Optionally, the cylinder cover, the cylinder barrel and the cylinder lower cover are connected by a double-headed bolt and a nut, and the piston rod and the piston block are fixed by the slotted nut.

[0012] Optionally, the guide ring is installed in the hole of the cylinder cover by overfitting.

[0013] Optionally, the frame and the special screw are fixed by a retaining ring, the guide plate and the piston rod are fixed by the cylindrical pin, and the special screw and the piston rod are threadedly connected.

[0014] Optionally, the guide rail and the cylinder cover are connected by a screw, the bearing and the guide plate are connected by a screw, and the guide sleeve and the cylinder cover are connected by a screw.

[0015] The present application provides a new type of valve regulating hydraulic actuator, which has the following beneficial effects:

[0016] The new type of valve regulating hydraulic actuator can solve the problem that the steam turbine regulating valve cannot be normally closed in the case of missing oil pressure of the actuator, can overcome the back pressure problem of the hydraulic actuator and reduce power consumption, the servo amplification device can be small, and can effectively cut off the oil path and unload the oil pressure when the steam turbine is overspeed, thereby ensuring safe operation of the equipment. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 It is an internal structure diagram of the present application;

[0018] Fig. 2 It is a top view structure diagram of the present application;

[0019] Fig. 3 It is a side view structure diagram of the present application;

[0020] Fig. 4 It is a hydraulic principle diagram of the present application.

[0021] In the figure: 1, steam ejector; 2, first joint; 3, connecting pipe; 4, first screw; 5, elbow lever; 6, thimble; 7, upper cover body; 8, upper spring seat; 9, spring body; 10, lower spring seat; 11, valve core; 12, throttle valve; 13, shell; 14, sleeve; 15, gasket; 16, first flange; 17, second screw; 18, electromagnetic valve; 19, pipe joint; 20, second flange; 21, first cylindrical pin; 22, connecting plate; 23, feedback plate; 24, pull rod; 25, guide rail; 26, guide rod; 27, special screw; 28, frame; 29, bearing; 30, guide plate; 31, special screw; 32, displacement sensor; 33, support; 34, guide sleeve; 35, guide ring; 36, cylinder upper cover; 37, piston rod; 38, cylinder barrel; 39, piston block; 40, piston ring; 41, slotted nut; 42, second cylindrical pin; 43, cylinder lower cover; 44, cover plate; 45, connecting body; 46, hexagonal bolt; 47, inner hexagonal screw; 48, exhaust pipe. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0023] Please refer to Figs. 1 to 4The application provides a technical scheme: a novel valve regulating hydraulic actuator, which comprises a steam generator 1, a first joint 2, a connecting pipe 3, a first screw 4, a top pin 6, an upper cover body 7, an upper spring seat 8, a spring body 9, a lower spring seat 10, a valve core 11, a throttle valve 12, a shell 13, a sleeve 14, a gasket 15, a first flange 16, a second screw 17, a solenoid valve 18, a pipe joint 19, a second flange 20, a first cylindrical pin 21, a connecting plate 22, a feedback plate 23, a pull rod 24, a guide rail 25, a guide rod 26, a special screw 27, a frame 28, a bearing 29, a guide plate 30, a special screw 31, a displacement sensor 32, a support 33, a guide sleeve 34, a guide ring 35, a cylinder upper cover 36, a piston rod 37, a cylinder barrel 38, a piston block 39, a piston ring 40, a slotted nut 41, a second cylindrical pin 42, a cylinder lower cover 43, a cover plate 44, a connecting body 45, a hexagonal bolt 46, an internal hexagonal screw 47 and an exhaust pipe 48, the bottom of the steam generator 1 is threadedly connected with the first joint 2, the bottom of the first joint 2 is threadedly connected with the connecting pipe 3, the connecting pipe 3 is threadedly connected with the upper cover body 7, the first screw 4 is threadedly connected in the bend angle lever 5, the top pin 6 is in spherical surface contact with the upper spring seat 8, the first screw 4 is in spherical surface contact with the top pin 6, the sleeve 14 and the shell 13 are fixed through a split screw, the gasket 15 and the first flange 16 are fixed on the shell 13 through the second screw 17, the solenoid valve 18, the second flange 20 and the cover plate 44 are all fixed on the shell 13 through screws, the connecting body 45 connects the shell 13 with the cylinder upper cover 36 and the cylinder lower cover 43 through the hexagonal bolt 46 and the internal hexagonal screw 47, the connecting plate 22 and the feedback plate 23 are connected through the first cylindrical pin 21, the guide rod 26 is installed in the hole of the feedback plate 23 through glue, the connecting plate 22 and the pull rod 24 are fixed through a cylindrical pin, the pull rod 24 and the piston rod 37 are threadedly connected, and the slotted nut 41 is connected with the piston rod 37 through the second cylindrical pin 42.

[0024] The exhaust pipe 48 is threadedly connected to the cylinder upper cover 36 and the cylinder lower cover through the pipe joint 19, the cylinder upper cover 36, the cylinder barrel 38 and the cylinder lower cover 43 are connected through double-headed bolts and nuts, the piston rod 37 and the piston block 39 are fixed through the slotted nut 41, the guide ring 35 is installed in the hole of the cylinder upper cover 36 through overfitting, the frame 28 and the special screw 31 are fixed through a check ring, the guide plate 30 and the piston rod 37 are fixed through a cylindrical pin, the special screw 31 and the piston rod 37 are threadedly connected, the guide rail 25 and the cylinder upper cover 36 are connected through a screw, the bearing 29 and the guide plate 30 are connected through a screw, and the guide sleeve 34 and the cylinder upper cover 36 are connected through a screw.

[0025] In summary, the new valve regulating hydraulic actuator, when in use, the pressure oil through the electro-hydraulic converter converts the 4 to 20 mA analog signal to 0.15 to 0.45 MPa oil pressure signal, through the oil motor secondary oil inlet P2 into the valve core 11 bottom through the control 4 to 20 mA analog signal change to control the secondary oil pressure 0.15 to 0.45 MPa change, when the oil pressure is equal to 0.15 MPa, by adjusting the first screw 4 and the special screw 31 to make the oil motor in full closed position, at this time the oil pressure and the area formed by the valve core 11 bottom is enough to overcome the valve core 11 gravity and the spring body 9 and the compression force, the valve core 11 is in the middle position of the sleeve 14, the valve core 11 will cut off the pressure oil and the return oil, the oil motor is closed;

[0026] The pipe joint 19 enters the oil motor and then enters the oil door through the electromagnetic valve 18. When the electromagnetic valve 18 is electrified, the oil inlet is cut off, and at the same time the oil at the bottom of the valve core 11 is discharged. Under the action of gravity and spring force, the valve core 11 is displaced downward. At this time, the lower cavity of the oil cylinder is connected with the return oil. Under the action of the spring force, the oil motor is quickly closed.

[0027] When in normal operation, the pressure oil enters the oil door through the oil inlet, and the secondary oil enters the bottom of the valve core 11 through the P2 port. When the oil pressure rises, the valve core 11 is displaced upward under the thrust of the oil pressure. At this time, the spring body 9 is compressed and at the same time the force is transmitted to the feedback plate 23 through the plunger 6, the first screw 4 and the angle lever 5. Because the valve core 11 is displaced upward, the pressure oil enters the oil dynamic lower cavity through the opening between the valve core 11 and the sleeve 14. At this time, the oil motor drives the feedback plate 23 to displace upward under the action of the pressure oil, and the feedback plate 23 generates a horizontal force which is transmitted to the spring body 9 through the angle lever 5, the first screw 4 and the plunger 6. When the combined force of the spring force and the gravity is equal to the force of the secondary oil pressure acting on the bottom of the valve core 11, the valve core 11 is again returned to the middle position, and the oil motor is in a stable state. When the secondary oil pressure decreases, the valve core 11 is displaced downward under the action of the spring force and the gravity, and the lower cavity of the oil motor is connected with the return oil. At this time, the oil motor is displaced in the closing direction, and at this time the feedback plate 23 generates a horizontal displacement, causing the feedback plate to rotate counterclockwise, and a part of the compression of the spring is released through the first screw 4 and the plunger 6, so that the force acting on the valve core 11 becomes smaller. When the spring force and the gravity are again balanced with the force of the secondary oil pressure acting on the valve core 11, the valve core 11 is again returned to the middle position, and the oil motor is again in a stable state. The above two kinds of movement realize the opening and closing of the regulating steam valve. The lower cavity of the oil cylinder is the oil pressure force, and the upper cavity of the oil cylinder is provided with an exhaust pipe 48 to supply air to the upper cavity in time and exhaust air to prevent air from being trapped in the upper cavity and affecting the operation of the oil motor. Embodiment

[0028] The single-sided oil inlet oil motor needs the spring body 9 to assist in realizing the opening and closing of the oil motor. The spring can be designed on the oil motor side or on the valve side. The spring designed on the oil motor side can be designed inside the oil cylinder or outside the oil cylinder.

[0029] The single-side oil inlet and spring closing mode can ensure that the spring closes the valve when the oil pressure of the oil motor is lost, and the spring and hydraulic structure overcome the defects of pure hydraulic structure, and the closing speed is faster in emergency. The benefit of single-side oil inlet is that when the oil cylinder is adjusted or closed, the back pressure of the oil return side of the oil cylinder is not affected, and the output is not affected. Because of the single-side oil inlet, the power consumption of the entire actuator is greatly reduced, so the corresponding servo amplifier can be reduced, the size of the corresponding device is reduced, the pipeline and the lubricating oil station are reduced, and the cost is greatly reduced. At the same time, an electromagnetic valve is integrated on the hydraulic actuator, when the steam turbine reaches 103% of the rated speed, receives the control system signal, quickly cuts off the secondary oil pressure, and at the same time unloads the secondary oil in the oil motor. The oil motor quickly displaces to the closing direction to drive the regulating steam valve to close, so as to ensure that the equipment runs within the rated speed range, and the equipment runs more safely.

[0030] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A new type of valve governing hydraulic actuator characterized by: Include steam (1), the first joint (2), connecting pipe (3), the first screw (4), elbow lever (5), the top needle (6), the upper cover body (7), the upper spring seat (8), spring body (9), the lower spring seat (10), the valve core (11), throttle (12), shell (13), sleeve (14), gasket (15), the first flange (16), the second screw (17), solenoid valve (18), pipe joint (19), the second flange (20), the first cylindrical pin (21), connecting plate (22), feedback plate (23), pull rod (24), guide rail (25), guide rod (26), special pin (27), frame (28), bearing (29), guide plate (30), special screw (31), displacement sensor (32), support (33), guide sleeve (34), guide ring (35), cylinder cover (36), piston rod (37), cylinder barrel (38), piston block (39), piston ring (40), slotted nut (41), the second cylindrical pin (42), oil cylinder lower cover (43), cover plate (44), connecting body (45), hexagonal bolt (46), internal hexagonal screw (47) and exhaust pipe (48), the bottom of steam (1) is threadedly connected with the first joint (2), the bottom of the first joint (2) is threadedly connected with the connecting pipe (3), the connecting pipe (3) is threadedly connected with the upper cover body (7), the first screw (4) is threadedly connected inside the elbow lever (5), the top needle (6) and the upper spring seat (8) are in spherical contact, the first screw (4) and the top needle (6) are in spherical contact, the sleeve (14) and the shell (13) are fixed by riding seam screw, the gasket (15) and the first flange (16) are fixed on the shell (13) by the second screw (17), the solenoid valve (18), the second flange (20) and the cover plate (44) are fixed on the shell (13) by screws, the connecting body (45) connects the shell (13) with the cylinder cover (36) and the oil cylinder lower cover (43) by the hexagonal bolt (46) and the internal hexagonal screw (47), the connecting plate (22) and the feedback plate (23) are connected by the first cylindrical pin (21), the guide rod (26) is installed in the hole of the feedback plate (23) by glue, the connecting plate (22) and the pull rod (24) are fixed by the cylindrical pin, the pull rod (24) and the piston rod (37) are connected by threads, the slotted nut (41) is connected with the piston rod (37) by the second cylindrical pin (42).

2. A new type of valve regulating hydraulic actuator according to claim 1, characterized in that: The exhaust pipe (48) is threadedly connected to the cylinder cover (36) and the oil cylinder lower cover by the pipe joint (19).

3. A new type of valve regulating hydraulic actuator according to claim 1, characterized in that: The cylinder cover (36), the cylinder barrel (38) and the oil cylinder lower cover (43) are connected by stud bolts and nuts, the piston rod (37) and the piston block (39) are fixed by the slotted nut (41).

4. A new type of valve regulating hydraulic actuator according to claim 1, characterized in that: The guide ring (35) is installed in the hole of the cylinder cover (36) by overfitting.

5. A new type of valve regulating hydraulic actuator according to claim 1, characterized in that: The frame (28) and the special screw (31) are fixed by a check ring, the guide plate (30) and the piston rod (37) are fixed by a cylindrical pin, and the special screw (31) and the piston rod (37) are connected by threads.

6. A new type of valve regulating hydraulic actuator according to claim 1, characterized in that: The guide rail (25) and the upper cylinder cover (36) are connected by a screw, the bearing (29) and the guide plate (30) are connected by a screw, and the guide sleeve (34) and the upper cylinder cover (36) are connected by a screw.

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