Intelligent double-gate-plate gate valve and control system

Abstract

The intelligent double-gate-plate gate valve comprises a valve body and a valve rod located in the valve body, a driving piece for driving the valve rod to move up and down is arranged above the valve body, the driving piece comprises a main air cylinder, an auxiliary air cylinder is installed in the main air cylinder, and the main air cylinder and the auxiliary air cylinder are connected with the same piston rod. The piston rod is connected with a valve rod, the valve rod is connected with a sliding block, dovetail blocks are integrally connected to the two sides of the sliding block, a left gate plate and a right gate plate are arranged on the two sides of the sliding block respectively, and first dovetail grooves connected with the dovetail blocks in a clamped mode are formed in the side, facing the sliding block, of the left gate plate. A second dovetail groove connected with the other dovetail block in a clamped mode is formed in the side, facing the sliding block, of the right gate plate, and a supporting plate is fixedly connected to the bottom of the sliding block. The pressure relief valve has the advantage that when the pressure of the middle cavity of the valve body is too high, the inlet valve seat achieves the automatic pressure relief function.

Description

Technical Field

[0001] The invention relates to the field of gate valves, in particular to an intelligent double-disc gate valve and a control system. Background Art

[0002] Gate valves are usually composed of valve bodies, gates, and valve seats. They are widely used in petrochemical plants because of their low flow resistance, simple shape, and long service life. However, the gate valves currently used do not have a switch speed control function during the valve opening and closing process. When the valve is quickly closed, the gate is likely to impact the valve body and even the pipeline, affecting the performance of the valve. Furthermore, the gate valves currently used are prone to pressure buildup in the valve body cavity as the medium temperature changes, causing the valve to be unable to open and close normally, so there is room for improvement. Summary of the invention

[0003] The purpose of the present invention is to provide an intelligent double-disc gate valve and control system to solve the problems raised in the above-mentioned background technology. The intelligent double-disc gate valve has low torque, inlet and outlet bidirectional sealing performance, and automatic pressure relief function. It is provided with a floating valve seat in the inlet direction and a fixed valve seat structure at the outlet end, which can achieve inlet and outlet bidirectional sealing. When the pressure in the valve body cavity is too high, the inlet valve seat has the advantage of automatic pressure relief function.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: an intelligent double-disc gate valve, comprising a valve body and a valve stem in the valve body, a driving member for driving the valve stem to move up and down is arranged above the valve body, the driving member comprises a main cylinder, a sub-cylinder is installed in the main cylinder, the main cylinder and the sub-cylinder are connected to the same piston rod, the piston rod is connected to the valve stem, the valve stem is connected to a slider, both sides of the slider are integrally connected with dovetail blocks, both sides of the slider are respectively provided with a left gate plate and a right gate plate, a first dovetail groove engaged with the dovetail block is arranged on the side of the left gate plate facing the slider, a second dovetail groove engaged with another dovetail block is arranged on the side of the right gate plate facing the slider, and a support plate is fixedly connected to the bottom of the slider.

[0005] By adopting the above technical solution, when the air source enters the cylinder from the air inlets P1 and P2, under the action of compressed air, the piston in the cylinder drives the piston rod, the piston rod drives the valve stem, the valve stem drives the slider to move upward, and the slider moves upward while driving the left gate plate to shrink toward the middle, the gate valve and the valve seat sealing surface are separated first, and the slider support plate then drives the left and right gate plates to continue to move upward, and the valve slowly opens; when the valve is opened to 20% of the full stroke, the 20% stroke position feedback device installed on the bracket receives the induction signal, and under the action of the positioner, the air intake path in the control system automatically switches from the slow route to the fast route, and the valve continues to open quickly until it is fully opened;

[0006] When the air source enters the cylinder from the air inlet P3 and P4, under the action of compressed air, the piston drives the piston rod, the piston rod drives the valve stem, the valve stem drives the slider and the gate to move downward quickly, and the valve closes downward quickly; when the valve is closed to 80% of the full stroke, the 20% stroke position feedback device installed on the bracket receives the sensing signal, and under the action of the positioner, the air inlet path in the control system automatically switches from the fast route to the slow route, the valve closing speed decreases, the gate moves downward slowly, the outer circle of the sealing disk contacts the limit platform at the bottom of the valve body, the slider continues to move downward, and the gate fits against the valve seat sealing surface under the action of the slider bevel until the valve is completely closed and sealed tightly;

[0007] The main and auxiliary cylinders, three feedback devices and positioners are reasonably set. When the valve is opened, the first 20% of the stroke can be opened slowly with a stroke adjustment function, and the remaining 80% of the stroke can be opened quickly; when the valve is closed, the first 80% of the stroke can be closed quickly, and the remaining 20% ​​of the stroke can be closed slowly with a stroke adjustment function. In addition to meeting the requirements of the on-site working conditions for the valve opening and closing speed, it can also reduce the adverse effects such as impact on the valve body and pipeline when the valve is opened and closed, making the valve performance more stable and reliable;

[0008] When the valve is opened, the gate and the valve seat sealing surface are separated first and then move relative to each other under the action of the slider bevel; when the valve is closed, the gate and the valve seat sealing surface center first move to a line, and under the action of the slider bevel, the sealing surface fits together again until the valve is tightly sealed. During the entire opening and closing process, the valve opening and closing torque is low, the friction between the sealing surfaces is small, and the valve has a long service life.

[0009] Preferably, a right valve seat is provided between the valve body and the right gate plate, a left valve seat is provided between the left gate plate and the valve body, and a preload spring is provided between the left valve seat and the valve body.

[0010] Preferably, an O-ring is provided on the side of the valve seat, a fireproof sealing ring is provided at one end of the left valve seat, and a soft sealing ring is provided between the left gate plate and the left valve seat.

[0011] Preferably, the piston rod is sleeved with a main piston in a main cylinder, one end of the main cylinder is provided with a P3 air inlet hole, the piston rod is sleeved with a secondary piston in a secondary cylinder, and the secondary cylinder is provided with P1 air inlet hole, P2 air inlet hole and P3 air inlet hole.

[0012] Preferably, the valve body includes a bracket in the middle, the bracket is connected to a feedback mounting plate, the feedback mounting plate is installed with a feedback device, and a clamping block is installed circumferentially of the valve stem.

[0013] Preferably, a manual device is installed at the connection between the valve stem and the piston rod, and a positioner is installed in the middle of the valve stem.

[0014] Preferably, the valve body is provided with a packing located in the circumference of the valve stem.

[0015] Another object of the present invention is to provide a control system for an intelligent double-disc gate valve, comprising an air storage tank and components, a filter pressure reducing valve, an air lock valve, a positioner, a two-position five-way solenoid valve, a two-position five-way air-controlled valve, a first air-controlled valve, a second air-controlled valve, a balancing valve, a double-cylinder pneumatic actuator, a double-disc gate valve, a two-position five-way solenoid valve and a feedback device.

[0016] As a further solution of the present invention: a fast circuit is arranged above the port of the positioner, and the fast circuit includes a first solenoid valve, a two-position five-way air-controlled valve, a speed-increasing valve, a first air-controlled valve and a second air-controlled valve; a slow circuit is arranged below the port of the positioner, and the slow circuit includes a second solenoid valve, a first air-controlled valve and a second air-controlled valve.

[0017] By adopting the above technical solution, when the main air source is from the air storage tank assembly through the filter pressure reducing valve and the air lock valve to the positioner, the positioner port is connected to the slow line below, the air source is connected through the 14th channel of the second solenoid valve, the PA of the second air control valve is connected, the air source enters the cylinder from P1 and P2, and the valve opens slowly. When the valve opens to 20% of the full stroke, the feedback device in the middle receives the induction signal, the positioner port is connected to the fast line above, the 14th channel of the first solenoid valve is connected, the two-position five-way air control valve PA is connected, and the first air control valve RA is connected after passing the speed increasing valve, and the air source enters the cylinder from P1 and P2, and the valve opens quickly until it is fully opened.

[0018] When the main air source is from the air tank assembly through the filter pressure reducing valve and the air lock valve to the positioner, the positioner port is connected to the upper fast line, the air source is connected through the 12 channel of the first solenoid valve, the PB channel of the air control valve is connected, and the PA channel of the first air control valve is connected after passing through the speed increasing valve. The air source enters the cylinder from P3 and P4, and the valve closes quickly. When the valve is closed to 80% of the full stroke, the feedback device receives the induction signal, and the positioner port is connected to the lower slow line, through the 12 channel of the second solenoid valve, and the RA channel of the first air control valve is connected. The air source enters the cylinder from P3 and P4, and the valve closes slowly until it is completely closed and tightly sealed.

[0019] The first gas-controlled valve and the second gas-controlled valve of the fast circuit and the slow circuit are the same component.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention is provided with a pneumatic actuator with a main and auxiliary cylinders. The valve bracket is respectively equipped with three feedback devices at the three positions of fully closed, 20% stroke, and fully open. A positioner is installed between the full strokes of the valve. When the valve is opened, the first 20% stroke can be opened slowly, and the remaining 80% stroke can be opened quickly, and the stroke adjustment function is provided; when the valve is closed, the first 80% stroke can be closed quickly, and the remaining 20% ​​stroke can be closed slowly, and the stroke adjustment function is provided. In addition to meeting the specific working conditions on site, it can also reduce the adverse effects such as impact on pipelines and valves when the valve is opened and closed, making the valve performance more stable and reliable;

[0022] 2. The present invention is provided with a slider with convex dovetail blocks on the left and right sides. The dovetail block on the left side of the slider is in direct contact with the dovetail groove of the left gate plate, and the dovetail block on the right side of the slider is in inclined contact with the dovetail groove of the right gate plate. When the valve is opened, under the action of the slider bevel, the gate plate and the valve seat sealing surface are first separated and then move relative to each other; when the valve is closed, the gate plate and the valve seat sealing surface center first move to a line, and under the action of the slider bevel, the sealing surface fits again until the valve is tightly sealed. During the entire opening and closing process, the valve opening and closing torque is low, the friction between the sealing surfaces is small, and the valve service life is long;

[0023] 3. There are left and right valve seats. The left valve seat adopts a floating valve seat structure. When the pressure in the middle cavity of the valve body increases, the pressure in the middle cavity will push the left valve seat to move toward the inlet end, and the valve can realize the automatic pressure relief function. The right valve seat adopts a fixed valve seat structure design, and the valve outlet end realizes forced sealing. The valve is installed on the pipeline. When the valve seat sealing surface is damaged and needs to be repaired and replaced, the valve seat parts can be directly taken out of the valve body. The valve has the function of online repair and replacement of the valve seat;

[0024] 4. The left valve seat sealing surface of the present invention adopts a soft and hard double sealing structure. The soft seal is made of RPTFE material, and the hard seal is made of STL high temperature resistant and wear resistant hard alloy material. When the valve pressure is low, the soft sealing material plays a major sealing role, and when the valve pressure is high, the hard sealing material plays a major sealing role. The valve can achieve a tight sealing effect at both low and high pressures.

[0025] 5. A circle of evenly distributed preload springs is arranged at the tail end face of the left valve seat to ensure that the valve seat and the gate sealing surface are closely fitted at low pressure to achieve a sealing effect. A convex step is arranged at the tail end of the left valve seat to cooperate with the concave step of the valve body flow channel to prevent impurities or flying dust in the medium from entering the back of the valve seat. The valve seat part of the valve has anti-slag and anti-dust functions. Two O-ring sealing structures are arranged on the outer circle of the left valve seat. A braided fireproof sealing ring structure is arranged at the tail of the left valve seat in contact with the valve body. The valve has fireproof and anti-static functions. Two limit steps for closing the gate in place are arranged at the bottom of the valve body to ensure that when the valve is fully closed, the center of the gate and the center of the valve seat are on the same straight line. The inner hole of the limit plate is fixed with the outer circle of the left valve seat. The bottom of the limit plate is installed on the left side of the valve body limit step to prevent the left valve seat from moving to the middle of the valve body opening when the valve is fully opened, causing interference to the valve closing;

[0026] 6. The outer circle of the valve stem adopts a stepped shape. When the valve is fully opened, the valve stem step and the inner hole of the valve cover form an inverted sealing structure. When the valve stem breaks and fails unexpectedly, the valve stem will not be blown out to places outside the valve under the pressure of the valve body cavity, which has the function of preventing the valve stem from blowing out. A central positioning hole step is set between the valve stem and the slider, and the surrounding of the positioning hole is fixed with bolts. The structure is simple and easy to install and maintain;

[0027] 7. The present invention consists of two parts: a pneumatic actuator and a valve body. The two parts adopt an independent modular design to facilitate the maintenance and upkeep of the valve in the later stage;

[0028] 8. There are manual and pneumatic switching mechanisms. The valve has two opening and closing operation modes, pneumatic and manual. The two modes can be switched freely according to the actual needs on site. The valve opening and closing process can be operated manually on site or remotely controlled through the control room. The piston rod of the manual device is provided with a sliding sleeve structure on the periphery. Without increasing the space height, the piston rod movement stroke is extended, the overall height of the manual device and the valve is reduced, and the processing and manufacturing costs are reduced. The U-shaped feedback mounting plate is used to firmly install the three feedbacks on the bracket with screws, which plays a role in accurately detecting the valve stroke. The clamping block is fixed to the valve stem with bolts, nuts and the valve stem flat square. There is an external convex structure in the middle of the clamping block to maintain an effective sensing distance with the feedback device contact. When the gas source on site is unstable or there is a sudden failure of the gas source, the valve still has the switching function, the positioner, and the valve switch stroke has a good and precise adjustment function;

[0029] 9. Two air control routes, fast and slow, are set up. The valve switch speed control is more intelligent and convenient. While meeting user needs, the valve has a longer service life and the sealing performance is more stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of an intelligent double-disc gate valve;

[0031] Figure 2 It is the principle diagram of the intelligent double-disc gate valve control system;

[0032] Figure 3 It is a structural schematic diagram of the connection relationship between the slider, the left gate plate and the right gate plate;

[0033] Figure 4 It is a structural schematic diagram of the connection relationship between the slider, the left gate plate and the right gate plate;

[0034] Figure 5 for Figure 1 A partial enlarged view of the middle I area;

[0035] Figure 6 for Figure 1 A partial enlarged view of the middle II area;

[0036] Figure 7 This is a schematic diagram of the structure of the echo device installation;

[0037] Figure 8 It is a structural schematic diagram of a split nut in an embodiment;

[0038] Fig. 9 It is a structural schematic diagram of the manual switching mechanism in the embodiment;

[0039] Fig.10 It is a structural schematic diagram of the connection relationship between the conversion block, the cylindrical pin and the split nut in the embodiment.

[0040] In the figure: 1. Valve body; 2. Right valve seat; 3. Right gate; 4. Support plate; 5. Fixing screw; 6. Left gate; 7. Left valve seat; 8. Fireproof sealing ring; 9. Preload spring; 10. Slider; 11. Screw; 12. Valve stem; 13. Soft sealing ring; 14. O-ring; 15. Limit plate; 16. Gasket; 17. Stud; 18. Valve cover; 19. Stud; 20. Positioner; 21. Bracket; 22. Manual device; 23. Sleeve; 24. Piston rod; 25. Auxiliary cylinder; 26. Main cylinder; 27. Main piston; 28. Auxiliary piston; 29. ​​Manual-pneumatic switching mechanism; 30. Feedback device ; 31. Clamp block; 32. Screw; 33. Pressure plate; 34. Packing; 35. Feedback mounting plate; 36. Dovetail block; 37. First dovetail groove; 38. Second dovetail groove; 39. Handle; 40. Conversion block; 41. Cylindrical pin; 42. Split nut; 43. Spiral groove; 44. Gas storage tank and components; 45. Filter pressure reducing valve; 46. Gas lock valve; 47. First solenoid valve; 48. Second solenoid valve; 49. Two-position five-way gas control valve; 50. Speed ​​increasing valve; 51. First gas control valve; 52. Second gas control valve; 53. Balance valve; 54. Double-cylinder pneumatic actuator; 55. Double-disc gate valve. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In the embodiment of the present invention,

[0043] An intelligent double-disc gate valve, such as Figure 1-Figure 10 As shown, it includes a valve body 1 and a valve stem 12 in the valve body 1, a driving member for driving the valve stem 12 to move up and down is arranged above the valve body 1, the driving member includes a main cylinder 26, a sub-cylinder 25 is installed in the main cylinder 26, the main cylinder 26 and the sub-cylinder 25 are connected to the same piston rod 24, the piston rod 24 is connected to the valve stem 12, the valve stem 12 is connected to a slider 10, dovetail blocks 36 are integrally connected to both sides of the slider 10, a left gate plate 6 and a right gate plate 3 are respectively arranged on both sides of the slider 10, a first dovetail groove 37 engaged with the dovetail block 36 is arranged on the side of the left gate plate 6 facing the slider 10, a second dovetail groove 38 engaged with another dovetail block 36 is arranged on the side of the right gate plate 3 facing the slider 10, and a support plate 4 is fixedly connected to the bottom of the slider 10. The support plate 4 is connected to the slider 10 by a limit screw 5. The valve stem 12 is connected to the slider 10 by a screw 11. A manual-pneumatic switching mechanism 29 is provided in the middle of the valve body.

[0044] A limit plate 15 is provided on one side of the left valve seat 7, and a gasket 16 is provided in the middle of the valve body 1. A first stud 17 and a second stud 19 are provided in the middle of the valve body 1. A valve cover 18 is provided in the middle of the valve body. A sliding sleeve 23 is provided around the piston rod 24.

[0045] A right valve seat 2 is provided between the valve body 1 and the right gate plate 3 , a left valve seat 7 is provided between the left gate plate 6 and the valve body 1 , and a preload spring 9 is provided between the left valve seat 7 and the valve body 1 .

[0046] A positioner 20 is provided in the middle of the valve stem.

[0047] An O-ring 14 is provided on the side of the valve seat, a fireproof sealing ring 8 is provided at one end of the left valve seat 7 , and a soft sealing ring 13 is provided between the left gate plate 6 and the left valve seat 7 .

[0048] The piston rod 24 is sleeved with a main piston 27 in a main cylinder 26, one end of the main cylinder 26 is provided with a P3 air inlet hole, and the piston rod 24 is sleeved with a secondary piston 28 in a secondary cylinder 25, and the secondary cylinder 25 is provided with a P1 air inlet hole, a P2 air inlet hole and a P3 air inlet hole.

[0049] The valve body 1 includes a bracket 21 in the middle, the bracket 21 is connected to a feedback mounting plate 35 , the feedback mounting plate 35 is mounted with a feedback device 30 , and a clamping block 31 is mounted around the valve stem 12 .

[0050] A manual device 22 is installed at the connection between the valve stem 12 and the piston rod 24 .

[0051] The valve body 1 is provided with a packing 34 in the circumferential direction of the valve stem 12. A pressing plate 33 is provided above the packing, and a screw 32 is provided on the pressing plate 33.

[0052] A control system for an intelligent double-disc gate valve includes an air storage tank and components 44, a filter pressure reducing valve 45, an air lock valve 46, a positioner 20, a first solenoid valve 47, a two-position five-way air control valve 49, a first air control valve 51, a second air control valve 52, a balancing valve 53, a double-cylinder pneumatic actuator 54, a double-disc gate valve 55, a second solenoid valve 48 and a feedback device 30.

[0053] A fast circuit is arranged above the port of the positioner 20, and the fast circuit includes a first solenoid valve 47, a two-position five-way air-controlled valve 49, a speed-increasing valve 50, a first air-controlled valve 51 and a second air-controlled valve 52. A slow circuit is arranged below the port of the positioner 20, and the slow circuit includes a second solenoid valve 48, a first air-controlled valve 51 and a second air-controlled valve 52.

[0054] The first air control valve 51 and the second air control valve 52 are two-position three-way air control valves.

[0055] The manual operating mechanism is provided with a conversion block 40 with a spiral groove 43, an operating handle 39 is provided on the conversion block 40, a split nut 42 is provided above the conversion block 40, and the split nut 42 and the conversion block 40 are connected by a cylindrical pin 41. When the handle 39 rotates the conversion block 40 to rotate, the split nut 42 moves horizontally under the drive of the spiral groove 43 and the cylindrical pin 41, and the split nut 42 and the valve stem diameter are converted from a meshing state to a separated state, thereby realizing the manual and pneumatic operation switching of the valve.

[0056] The locator selected is a Fisher locator, and its model is DVC6200.

[0057] Working principle:

[0058] When the air source enters the cylinder from the air inlets P1 and P2, under the action of compressed air, the piston in the cylinder drives the piston rod 24, the piston rod 24 drives the valve stem 12, and the valve stem 12 drives the slider 10 to move upward. While the slider 10 moves upward, it drives the left gate plate 6 to shrink toward the middle, the gate valve and the valve seat sealing surface are separated first, and the slider 10 support plate 4 then drives the left and right gate plates 3 to continue to move upward, and the valve slowly opens; when the valve is opened to 20% of the full stroke, the 20% stroke position feedback device 30 installed on the bracket 21 receives the induction signal, and under the action of the positioner 20, the air intake path in the control system automatically switches from the slow route to the fast route, and the valve continues to open quickly until it is fully opened;

[0059] When the air source enters the cylinder from the air inlets P3 and P4, under the action of compressed air, the piston drives the piston rod 24, the piston rod 24 drives the valve stem 12, the valve stem 12 drives the slider 10 and the gate to move downward quickly, and the valve closes downward quickly; when the valve is closed to 80% of the full stroke, the 20% stroke position feedback device 30 installed on the bracket 21 receives the sensing signal, and under the action of the positioner 20, the air inlet path in the control system automatically switches from the fast route to the slow route, the valve closing speed decreases, the gate moves downward slowly, the outer circle of the sealing disk contacts the limit platform at the bottom of the valve body 1, the slider 10 continues to move downward, and the gate fits against the valve seat sealing surface under the action of the slider 10 bevel until the valve is completely closed and sealed tightly;

[0060] The main and auxiliary cylinders 25, three feedback devices 30 and positioner 20 are reasonably set. When the valve is opened, the first 20% of the stroke can be opened slowly with a stroke adjustment function, and the remaining 80% of the stroke can be opened quickly; when the valve is closed, the first 80% of the stroke can be closed quickly, and the remaining 20% ​​of the stroke can be closed slowly with a stroke adjustment function. In addition to meeting the requirements of the on-site working conditions for the valve opening and closing speed, it can also reduce the adverse effects such as impact on the valve body 1 and the pipeline when the valve is opened and closed, making the valve performance more stable and reliable;

[0061] When the valve is opened, the gate and the valve seat sealing surface are separated first and then move relative to each other under the action of the slider 10 bevel; when the valve is closed, the gate and the valve seat sealing surface center first move to a line, and under the action of the slider 10 bevel, the sealing surface fits together again until the valve is tightly sealed. During the entire opening and closing process, the valve opening and closing torque is low, the friction between the sealing surfaces is small, and the valve has a long service life.

[0062] When the main air source is from the air storage tank assembly through the filter pressure reducing valve 45 and the air lock valve 46 to the positioner 20, the positioner 20 port is connected to the slow circuit below, the air source is connected through the 14th channel of the second solenoid valve 48, the PA of the second air control valve 52 is connected, the air source enters the cylinder from P1 and P2, and the valve opens slowly. When the valve opens to 20% of the full stroke, the feedback device 30 in the middle receives the sensing signal, the positioner 20 port is connected to the fast circuit above, the 14th channel of the first solenoid valve 47 is connected, the two-position five-way air control valve 49PA is connected, and the first air control valve 51RA is connected through the speed increasing valve 50, and the air source enters the cylinder from P1 and P2, and the valve opens quickly until it is fully opened;

[0063] When the main air source is from the air tank assembly through the filter pressure reducing valve 45 and the air lock valve 46 to the positioner 20, at this time, the positioner 20 port is connected to the upper fast line, the air source is connected through the 12 channel of the first solenoid valve 47, the PB channel of the air control valve is connected, and the speed increasing valve 50 is connected to the PA channel of the first air control valve 51. The air source enters the cylinder from P3 and P4, and the valve closes quickly. When the valve is closed to 80% of the full stroke, the feedback device 30 receives the induction signal, and the positioner 20 port is connected to the lower slow line, and is connected through the 12 channel of the second solenoid valve 48 and the RA channel of the first air control valve 51. The air source enters the cylinder from P3 and P4, and the valve closes slowly until it is completely closed and tightly sealed.

[0064] The first gas-controlled valve 51 and the second gas-controlled valve 52 of the fast circuit and the slow circuit are the same component.

[0065] Both the first solenoid valve 47 and the second solenoid valve 48 are two-position five-way solenoid valves.

[0066] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An intelligent double-disc gate valve, comprising a valve body (1) and a valve stem (12) in the valve body (1), wherein a driving member for driving the valve stem (12) to move up and down is arranged above the valve body (1), characterized in that: The driving member comprises a main cylinder (26), a sub-cylinder (25) is installed in the main cylinder (26), the main cylinder (26) and the sub-cylinder (25) are connected to the same piston rod (24), the piston rod (24) is connected to a valve stem (12), the valve stem (12) is connected to a slider (10), both sides of the slider (10) are integrally connected with dovetail blocks (36), both sides of the slider (10) are respectively provided with a left gate plate (6) and a right gate plate (3), the left gate plate (6) is provided with a first dovetail groove (37) engaged with the dovetail block (36) on the side facing the slider (10), the right gate plate (3) is provided with a second dovetail groove (38) engaged with another dovetail block (36) on the side facing the slider (10), and the bottom of the slider (10) is fixedly connected with a support plate (4).

2. The intelligent double-disc gate valve according to claim 1 is characterized in that: A right valve seat (2) is arranged between the valve body (1) and the right gate plate (3), a left valve seat (7) is arranged between the left gate plate (6) and the valve body (1), and a preload spring (9) is arranged between the left valve seat (7) and the valve body (1).

3. The intelligent double-disc gate valve according to claim 2 is characterized in that: An O-ring (14) is arranged on the side of the valve seat, a fireproof sealing ring (8) is arranged at one end of the left valve seat (7), and a soft sealing ring (13) is arranged between the left gate plate (6) and the left valve seat (7).

4. The intelligent double-disc gate valve according to claim 1 is characterized in that: The piston rod (24) is sleeved with a main piston (27) in a main cylinder (26), one end of the main cylinder (26) is provided with a P3 air inlet hole, the piston rod (24) is sleeved with a secondary piston (28) in a secondary cylinder (25), and the secondary cylinder (25) is provided with a P1 air inlet hole, a P2 air inlet hole and a P3 air inlet hole.

5. The intelligent double-disc gate valve according to claim 1 is characterized in that: The valve body (1) comprises a bracket (21) in the middle, the bracket (21) is connected to a feedback mounting plate (35), the feedback mounting plate (35) is installed with a feedback device (30), and a clamping block (31) is installed in the circumference of the valve stem (12).

6. The intelligent double-disc gate valve according to claim 1 is characterized in that: A manual device (22) is installed at the connection between the valve stem (12) and the piston rod (24), and a positioner (20) is installed in the middle of the valve stem (12).

7. The intelligent double-disc gate valve according to claim 1 is characterized in that: The valve body (1) is provided with a packing (34) located in the circumferential direction of the valve stem (12).

8. A control system for an intelligent double-disc gate valve according to claim 1, characterized in that: The invention comprises an air storage tank and components (44), a filter pressure reducing valve (45), an air lock valve (46), a positioner (20), a first solenoid valve (47), a two-position five-way air control valve (49), a first air control valve (51), a second air control valve (52), a balancing valve (53), a double-cylinder pneumatic actuator (54), a double-disc gate valve (55), a second solenoid valve (48) and a feedback device (30).

9. The control system of the intelligent double-disc gate valve according to claim 8 is characterized in that: A fast circuit is arranged above the port of the positioner (20), and the fast circuit includes a first solenoid valve (47), a two-position five-way air-controlled valve (49), a speed-increasing valve (50), a first air-controlled valve (51), and a second air-controlled valve (52); a slow circuit is arranged below the port of the positioner (20), and the slow circuit includes a second solenoid valve (48), a first air-controlled valve (51), and a second air-controlled valve (52).

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