A wear-resistant pneumatic control valve for a dusty environment

Abstract

The present invention discloses a wear-resistant pneumatic control valve for a dusty environment, which relates to the technical field of pneumatic control valves and includes a valve stem, an adjustment unit, a valve barrel, a valve body assembly, and a positioning unit. One end of the valve stem is connected to the adjustment unit, and the other end of the valve stem is connected to the valve body assembly. The valve barrel is sleeved outside the valve stem, the upper end of the valve barrel is fixedly connected to the adjustment unit, and the lower end of the valve barrel is fixedly connected to the valve body assembly. The positioning unit is arranged inside the valve barrel, one end of the positioning unit is fixedly connected to the valve barrel, and the other end of the positioning unit is fixedly connected to the valve stem. The air flow port of the present invention uses the directional air flow generated during the start-up and shutdown processes of the control valve for guiding. On the one hand, the dust impurities in the air flow are filtered out, avoiding the entry of impurities into the interior of the control valve and affecting the service life of the control valve. On the other hand, the air flow guiding causes the vibration of the filter screen in the up-and-down and left-and-right directions, greatly improving the cleanliness of the surface of the filter screen during the dust filtering process and realizing continuous ventilation filtration.

Description

Technical Field

[0001] The present invention relates to the technical field of pneumatic control valves, and particularly to a wear-resistant pneumatic control valve for a dusty environment. Background Art

[0002] During the power generation process in a thermal power station, coal is burned, generating a large amount of residue. A large amount of residue will be mixed into the wastewater of the power station, and there will also be relatively more dust impurities in the air. The control valves used in conventional wastewater pipelines will greatly reduce their service life in such an environment and cannot meet the usage requirements.

[0003] For control valves used in a dusty environment, pneumatic control is generally adopted to avoid direct manual operation. However, during the pneumatic control process, dust impurities in the air are likely to block the filter screen of the control valve, thereby affecting the control accuracy.

[0004] Generally, a sealing layer is provided on the valve surface. The sealing layer fills the space between the valve and the connecting hole when the valve is closed. However, since the wastewater in the power station contains a large amount of waste residue impurities, when the valve is closed, the flow gap decreases, and the waste residue mixed sewage flows through the gap, resulting in a relatively increased flow rate. The waste residue is likely to cause wear to the sealing layer, and it is difficult for the worn sealing layer to achieve strict sealing.

[0005] During the closing process of the valve, the existence of the water hammer effect has always been a very important issue. The water hammer acts on the valve position, causing damage to the valve and greatly reducing the service life of the control valve. Existing equipment lacks a buffer mechanism for water hammer. Summary of the Invention

[0006] The purpose of the present invention is to provide a wear-resistant pneumatic control valve for a dusty environment to solve the problems raised in the above background art.

[0007] To solve the above technical problems, the present invention provides the following technical solutions: A wear-resistant pneumatic control valve for a dusty environment, comprising a valve stem, an adjustment unit, a valve barrel, a valve body assembly, and a positioning unit. One end of the valve stem is connected to the adjustment unit, and the other end of the valve stem is connected to the valve body assembly. The valve barrel is sleeved outside the valve stem, the upper end of the valve barrel is tightly connected to the adjustment unit, and the lower end of the valve barrel is tightly connected to the valve body assembly. The positioning unit is arranged inside the valve barrel, one end of the positioning unit is tightly connected to the valve barrel, and the other end of the positioning unit is tightly connected to the valve stem. The adjustment unit controls the lifting of the valve stem. When the valve stem rises, the valve body assembly is opened, and the fluid passes through the control valve. When the valve stem descends, the valve body assembly is blocked, and the fluid is cut off. The positioning unit detects the position change of the valve stem, and the valve barrel isolates the positioning unit from the outside world to prevent dust in the air from entering the valve. The control valve of the present invention is used for sewage transportation in a thermal power station. The fluid inside the pipeline contains a lot of impurities, and the external working environment also contains a lot of dust. The service life of a conventional control valve is relatively short in such an environment. Therefore, this invention is specifically designed to extend the service life. The air flow port of the present invention uses the directional air flow generated during the startup and shutdown processes of the control valve for guiding. On the one hand, it filters out the dust impurities in the air flow, preventing the impurities from entering the control valve and affecting its service life. On the other hand, the air flow guiding causes the filter screen to vibrate in the up-down and left-right directions, greatly improving the cleanliness of the filter screen surface during the dust filtering process and achieving continuous ventilation filtration.

[0008] Further, the adjustment unit includes a pneumatic chamber, an adjustment cover, a return spring, an air flow port, and a control port. The pneumatic chamber is tightly connected to the upper end of the valve barrel. The adjustment cover is arranged inside the pneumatic chamber and is slidably connected to the pneumatic chamber. The return spring is arranged below the adjustment cover. One end of the return spring is tightly connected to the inner wall of the pneumatic chamber, and the other end of the return spring is tightly connected to the adjustment cover. The valve stem is tightly connected to the adjustment cover and is slidably connected to the pneumatic chamber. The air flow port is arranged on the lower side of the pneumatic chamber, and the control port is arranged on the upper side of the pneumatic chamber and is connected to an external air flow pipeline. The external air flow pipeline is connected to a compressed air pipeline, and the intake and exhaust are controlled by a solenoid valve. When the valve needs to be closed, gas is input at the control port, the adjustment cover is pressed down, driving the valve stem to move downward, and the valve is closed. When the valve needs to be opened, the gas is discharged at the control port, and the return spring pushes the adjustment cover upward, and the valve is opened. The air flow change below the adjustment cover is carried out through the air flow port.

[0009] Furthermore, the air flow port includes a flow hood, a fixing ring, a mounting spring, a movable plate, a horizontal groove, and a filter plate. The flow hood is fixedly connected to the bottom of the pneumatic chamber, and the top of the flow hood is connected to the inside of the pneumatic chamber. The fixing ring is fixedly connected to the inner side wall of the flow hood, and the movable plate is slidably connected to the inner side wall of the flow hood. One end of the mounting spring is fixedly connected to the fixing ring, and the other end of the mounting spring is fixedly connected to the movable plate. The horizontal groove is provided on the movable plate, and the filter plate is slidably connected to the horizontal groove. An inclined hole array is provided at the middle position of the filter plate, and the inclined hole array communicates with the upper and lower ends of the filter plate. A filter net is provided at the end of the inclined hole array away from the pneumatic chamber, and the filter net covers the inclined hole array. When the regulating cover is moved by pneumatic control, gas will also be input and output correspondingly below the regulating cover. When the gas is input and output, it passes through the filter plate. Under normal conditions, the filter plate is suspended below the fixing ring. The input of the air flow will push the movable plate upward, and the output of the air flow will stretch the movable plate downward. After the input and output are completed, the movable plate is pulled back to its original position by the mounting spring. During the reset process, the movable plate vibrates, and when the movable plate vibrates, the filter plate swings up and down. When the filter plate swings up and down, the air flow is guided by the inclined hole array and generates a lateral force. The lateral forces generated by the air flow up and down are in opposite directions. Therefore, each time the regulating valve is started and stopped, the filter plate vibrates in the up-down direction and the left-right direction, and the dust and impurities blocked by the filter net vibrate and fall off, avoiding the blockage of the filter net. The air flow port of the present invention uses the directional air flow generated during the start-up and closing processes of the regulating valve for guiding. On the one hand, it filters out the dust and impurities in the air flow, avoiding the entry of impurities into the regulating valve and affecting the service life of the regulating valve. On the other hand, the air flow guiding causes the filter net to vibrate in the up-down direction and the left-right direction, greatly improving the cleanliness of the surface of the filter net during the dust filtering process and realizing continuous ventilation and filtering.

[0010] Furthermore, the valve body assembly includes a valve seat, a valve core, an upper valve chamber, a lower valve chamber, a contraction groove, an input flange, and an output flange. The valve seat is fixedly connected to the valve barrel, the valve core is fixedly connected to the valve stem, the upper valve chamber and the lower valve chamber are provided inside the valve seat, the upper valve chamber is connected to the lower valve chamber, the contraction groove is provided above the upper valve chamber, the input flange and the output flange are fixedly connected to the valve seat, the input flange is connected to the lower valve chamber, and the output flange is connected to the lower valve chamber. External fluid is input from the input flange and flows out from the output flange. The valve core moves under the drive of the valve stem. When the valve is closed, the valve core blocks the connection between the upper valve chamber and the lower valve chamber. When the valve is opened, the valve core is located in the contraction groove.

[0011] Furthermore, a tapered hole is provided between the upper valve chamber and the lower valve chamber, and the tapered hole connects the upper valve chamber and the lower valve chamber. A tapered plug is provided at the bottom of the valve core, and the contour of the tapered plug is the same as that of the tapered hole. A sealing sleeve is provided on the outside of the tapered plug. When the regulating valve needs to be closed, the tapered plug is inserted into the tapered hole, and the sealing sleeve is clamped between the tapered plug and the tapered hole to seal the two.

[0012] Furthermore, the conical plug is provided with an inlet tube, a conducting hole, and a blocking net inside, and an expansion hole is provided inside the sealing sleeve. The inlet tube is provided at the bottom of the conical plug, the air inlet end of the inlet tube is tightly connected to the blocking net, one end of the conducting hole is connected to the inlet tube, and the other end of the conducting hole is connected to the expansion hole. There are multiple groups of expansion holes and conducting holes, and the multiple groups of expansion holes and conducting holes are evenly distributed around the inlet tube. A micro-sealing ring is provided on the side of the expansion hole away from the conducting hole, and the outer edge of the micro-sealing ring slightly exceeds the position of the conducting hole. When the conical plug blocks the conical hole, the micro-sealing ring is squeezed by the side wall of the conical hole, and the micro-sealing ring is sunken, which will block the conducting hole. A sealing layer is generally provided on the surface of the valve, and the sealing layer is filled in the valve and the connecting hole when the valve is closed. However, since the wastewater of the power station contains more waste slag impurities, when the valve is closed, the flow gap is reduced, and the waste slag mixed with sewage flows through the gap, and the flow rate will be relatively increased. The waste slag can easily cause wear of the sealing layer, and it is difficult to achieve strict sealing of the worn sealing layer. When the conical plug provided by the present invention closes the valve, part of the water flow will flow away from the sealing gap, and part of the water flow will enter the inlet tube. The blocking net provided on the inlet tube will filter the impurities, and the filtered fluid will be divided into various conduction holes, and then output from various expansion holes. The filtered fluid enters the sealing gap from various places of the sealing sleeve, spreads on the surface of the sealing sleeve, forms a protective fluid, and avoids the impurities from wearing the surface of the sealing sleeve. When the valve is completely closed, the filtered fluid cannot be discharged and will be blocked in the expansion hole. The expansion hole can be elastically deformed and the volume increases, and the volume of the sealing sleeve will be enlarged by each expansion hole, further improving the sealing effect. The conical plug of the present invention filters and drains part of the sewage, and distributes the filtered fluid to the surface of the sealing sleeve to form a protective layer of the sealing sleeve, thereby avoiding the wear of the sealing sleeve by impurities in the sealing gap, greatly improving the wear resistance of the sealing sleeve, and extending the service life of the regulating valve. On the other hand, after the valve is closed, the pressure of the filtered fluid causes the expansion hole to deform, increases the volume of the sealing sleeve, further enhances the sealing pressure at the sealing position, and enhances the sealing effect.

[0013] Furthermore, a flow guiding unit is provided in the inner wall of the input flange. There are multiple groups of flow guiding units, which are evenly distributed around the input flange. The flow guiding unit includes a sliding plate, a drainage hole, a discharge hole, an adjustment cavity, a sliding block, and a guiding block. The sliding plate is slidably connected to the inner wall of the input flange. The sliding block, the guiding block, and the sliding plate are fixedly connected. The adjustment cavity is embedded in the surface of the inner wall of the input flange. A pushing spring is arranged in the adjustment cavity. The sliding block is slidably connected to the adjustment cavity. One end of the pushing spring is fixedly connected to the side wall of the adjustment cavity, and the other end of the pushing spring is fixedly connected to the sliding block. The guiding block is arranged at one end of the sliding plate close to the valve seat. The side of the guiding block close to the valve seat is set as a vertical surface, and the side of the guiding block away from the valve seat is set as an arc-shaped guiding surface. The drainage hole and the discharge hole are also embedded in the inner wall of the input flange. The drainage hole is arranged at the end away from the valve seat, and the discharge hole is arranged at the end close to the valve seat. The ends of the drainage hole and the discharge hole extending into the side wall of the input flange are inclined towards the valve seat. A flow guiding channel is arranged between the drainage hole and the discharge hole. Two openings are arranged on the sliding plate, and the distance between the openings is equal to the distance between the drainage hole and the discharge hole. In the conducting state, the sliding plate seals the drainage hole and the discharge hole, and the pipeline fluid flows normally. When the valve is closed, the fluid that originally flowed through the edge gap position is blocked. Under the action of inertia, the fluid flows back along the edge. The flowing-back fluid impacts on the surface of the guiding block. The vertical surface of the guiding block faces the flowing-back fluid, generating a large thrust. The sliding plate is pushed, and the pushing spring is compressed. After the sliding plate moves, the drainage hole, the discharge hole, and the openings on the sliding plate are conducted. Since the drainage hole is far from the valve position, when the valve is closed, the subsequent water flow still has a tendency to flow forward. At the drainage hole, a part of the fluid flows in. At the discharge hole, the part of the fluid flows out again. The inclined direction of the discharge hole causes the discharged part of the fluid to collide with the oncoming main fluid. The part of the fluid faces the center position of the main fluid, and part of the impact force of the main fluid is consumed by the part of the fluid. The subsequent water hammer effect will be relatively reduced, and the impact on the valve is reduced. After the water flow returns to calm, the pushing spring pushes the sliding block to reset again, and the sliding plate also resets accordingly. The flow guiding unit of the present invention will separate multiple strands of part of the fluid from the main pipeline fluid when closing the valve, and guide the flow direction of the part of the fluid, and borrow the flow of the part of the fluid to reduce the flow kinetic energy of the main fluid. And this kind of flow separation and blockage only occurs at the moment when the valve is closed and the fluid flows back. On the one hand, it reduces the impact force of the instantaneous water hammer, and on the other hand, it also ensures the smoothness of the flow in the conducting state.

[0014] Furthermore, the positioning unit includes a position sensor and a sliding piece. There are two groups of position sensors, which are fixedly connected to the inner wall of the valve barrel. The sliding piece is fixedly connected to the valve stem. The setting positions of the two groups of position sensors respectively correspond to the positions of the valve stem in the valve opening state and the valve closing state. The valve stem drives the sliding piece to move. When the sliding piece passes through the position sensor, a position signal is output, and the external control device controls the input and output of the air flow according to the signal.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The air outlet of the present invention utilizes the directional airflow generated during the start-up and closing processes of the regulating valve for guiding. On the one hand, it filters out dust and impurities in the airflow, preventing impurities from entering the interior of the regulating valve and affecting its service life. On the other hand, the airflow guiding causes vibrations in the up-down and left-right directions of the filter net, greatly improving the cleanliness of the filter net surface during the dust filtration process and achieving continuous ventilation filtration. The conical plug of the present invention filters and diverts part of the sewage, and distributes the filtered fluid onto the surface of the sealing sleeve to form a protective layer for the sealing sleeve, avoiding wear of the sealing sleeve by impurities in the sealing gap, greatly enhancing the wear resistance of the sealing sleeve, and extending the service life of the regulating valve. On the other hand, after the valve is closed, the pressure of the filtered fluid deforms the expansion holes, increasing the volume of the sealing sleeve, further enhancing the sealing pressure at the sealing position, and strengthening the sealing effect. The diversion unit of the present invention will separate multiple sub-streams from the main pipeline fluid when closing the valve and guide the flow direction of the sub-streams. By borrowing the flow of the sub-streams, the flow kinetic energy of the main stream is reduced, and this kind of flow diversion and prevention only occurs at the moment when the valve is closed and the fluid flows back. On the one hand, it reduces the impact force of the instantaneous water hammer, and on the other hand, it also ensures the smoothness of the flow during the conducting state. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0017] Figure 1 is the overall structural schematic diagram of the present invention;

[0018] Figure 2 is Figure 1 the partial enlarged view of part A of

[0019] Figure 3 is the internal structure display diagram of the air outlet of the present invention;

[0020] Figure 4 is the working principle diagram of the filter plate of the present invention;

[0021] Figure 5 is the cross-sectional view of the valve core structure of the present invention;

[0022] Figure 6 is the schematic diagram of the expansion holes of the present invention in the valve closed state;

[0023] Figure 7 is the cross-sectional view of the overall structure of the input flange of the present invention;

[0024] Figure 8 is Figure 7 the partial enlarged view of part B of

[0025] Figure 9 is the working schematic diagram of the input flange of the present invention in the valve closed state;

[0026] In the figure: 1 - valve stem, 2 - adjusting unit, 21 - pneumatic chamber, 22 - adjusting cover, 23 - return spring, 24 - air flow port, 241 - flow-through cover, 242 - fixing ring, 243 - mounting spring, 244 - movable plate, 245 - horizontal groove, 246 - filter plate, 247 - inclined hole array, 25 - control port, 3 - valve barrel, 4 - valve body assembly, 41 - valve seat, 42 - valve core, 421 - conical plug, 422 - sealing sleeve, 423 - inlet flow cylinder, 424 - through hole, 425 - blocking net, 426 - expansion hole, 43 - upper valve chamber, 44 - lower valve chamber, 45 - contraction groove, 46 - input flange, 461 - sliding plate, 462 - drainage hole, 463 - discharge hole, 464 - adjustment chamber, 465 - sliding block, 466 - guiding block, 47 - output flange, 48 - conical hole, 5 - positioning unit. Detailed implementation manners

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] As Figure 1As shown, a wear-resistant pneumatic regulating valve for dusty environment includes a valve stem 1, a regulating unit 2, a valve cylinder 3, a valve body assembly 4, and a positioning unit 5. One end of the valve stem 1 is connected to the regulating unit 2, and the other end of the valve stem 1 is connected to the valve body assembly 4. The valve cylinder 3 is sleeved on the outside of the valve stem 1, and the upper end of the valve cylinder 3 is tightly connected to the regulating unit 2, and the lower end of the valve cylinder 3 is tightly connected to the valve body assembly 4. The positioning unit 5 is arranged inside the valve cylinder 3, and one end of the positioning unit 5 is tightly connected to the valve cylinder 3, and the other end of the positioning unit 5 is tightly connected to the valve stem 1. The regulating unit 2 controls the lifting and lowering of the valve stem 1. When the valve stem 1 rises, the valve body assembly 4 is turned on, and the fluid passes through the regulating valve. When the valve stem 1 descends, the valve body assembly 4 is blocked, and the fluid is cut off. The positioning unit 5 detects the position change of the valve stem 1, and the valve cylinder 3 isolates the positioning unit 5 from the outside to prevent dust in the air from entering the valve. The regulating valve of the present invention is used for sewage transportation in thermal power plants. There are many impurities mixed in the fluid inside the pipeline, and the external working environment also contains a lot of dust. The service life of conventional regulating valves in such an environment is short, so this invention is specifically set to extend the service life. The airflow port 24 of the present invention is guided by the directional airflow generated during the start-up and closing process of the regulating valve. On the one hand, dust impurities in the airflow are filtered out, and impurities are prevented from entering the regulating valve and affecting the service life of the regulating valve. On the other hand, the airflow guidance causes the filter screen to vibrate in the up and down directions and the left and right directions, which greatly improves the cleanliness of the filter screen surface during the dust filtering process and realizes continuous ventilation filtration.

[0029] like Figure 1 As shown, the regulating unit 2 includes a pneumatic chamber 21, an regulating cover 22, a return spring 23, an air flow port 24, and a control port 25. The pneumatic chamber 21 is fastened to the upper end of the valve cylinder 3, the regulating cover 22 is arranged inside the pneumatic chamber 21, the regulating cover 22 and the pneumatic chamber 21 are slidably connected, the return spring 23 is arranged on the lower side of the regulating cover 22, one end of the return spring 23 is fastened to the inner wall of the pneumatic chamber 21, the other end of the return spring 23 is fastened to the regulating cover 22, the valve stem 1 is fastened to the regulating cover 22, the valve stem 1 is slidably connected to the pneumatic chamber 21, the air flow port 24 is arranged on the lower side of the pneumatic chamber 21, the control port 25 is arranged on the upper side of the pneumatic chamber 21, and the control port 25 is connected to an external air flow duct. The external air flow pipeline is connected to the compressed air pipeline, and the air intake and exhaust are controlled by the solenoid valve. When the valve needs to be closed, gas is input at the control port 25, the regulating cover 22 is pressed down, driving the valve stem 1 to move downward, and the valve is closed. When the valve needs to be opened, gas is discharged from the control port, the return spring lifts the regulating cover, the valve is opened, and the airflow change below the regulating cover 22 is carried out through the airflow port 24.

[0030] like Figure 3 , Figure 4As shown, the air flow port 24 includes a circulation cover 241, a fixing ring 242, a mounting spring 243, a movable plate 244, a horizontal groove 245, and a filter plate 246. The circulation cover 241 is fixedly connected to the bottom of the pneumatic chamber 21, and the top of the circulation cover 241 is connected to the inside of the pneumatic chamber 21. The fixing ring 242 is fixedly connected to the inner side wall of the circulation cover 241, and the movable plate 244 is slidably connected to the inner side wall of the circulation cover 241. One end of the mounting spring 243 is fixedly connected to the fixing ring 242, and the other end of the mounting spring 243 is fixedly connected to the movable plate 244. The horizontal groove 245 is provided on the movable plate 244, and the filter plate 246 is slidably connected to the horizontal groove 245. An inclined hole array 247 is provided at the middle position of the filter plate 246. The inclined hole array 247 communicates with the upper and lower ends of the filter plate 246. A filter net is provided at one end of the inclined hole array 247 away from the pneumatic chamber 21, and the filter net covers the inclined hole array 247. When the regulating cover 22 is moved by pneumatic control, gas is also input and output correspondingly below the regulating cover 22. When the gas is input and output, it passes through the filter plate 246. The filter plate 246 is normally suspended below the fixing ring 242. The input of the air flow will push the movable plate 244 upward, and the output of the air flow will stretch the movable plate 244 downward. After the input and output are completed, the movable plate 244 is pulled back to its original position by the mounting spring 243. During the reset process, the movable plate 244 vibrates, and the filter plate 246 swings up and down when vibrating. When the filter plate 246 swings up and down, the air flow is guided by the inclined hole array 247 and a lateral force is generated. The lateral forces generated by the air flow up and down are in opposite directions. Therefore, every time the regulating valve is started and stopped, the filter plate 246 vibrates in the up and down directions and the left and right directions, and the dust and impurities blocked by the filter net vibrate and fall off, avoiding the blockage of the filter net. The air flow port 24 of the present invention utilizes the directional air flow generated during the start-up and closing processes of the regulating valve for guiding. On the one hand, it filters out the dust and impurities in the air flow, avoiding the entry of impurities into the regulating valve and affecting the service life of the regulating valve. On the other hand, the air flow guiding causes the filter net to vibrate in the up and down directions and the left and right directions, greatly improving the cleanliness of the surface of the filter net during the dust filtering process and realizing continuous air filtering.

[0031] As Figure 1 , Figure 5As shown in the figure, the valve body assembly 4 includes a valve seat 41, a valve core 42, an upper valve chamber 43, a lower valve chamber 44, a contraction groove 45, an input flange 46, and an output flange 47. The valve seat 41 is fixedly connected to the valve barrel 3, the valve core 42 is fixedly connected to the valve stem 1. The upper valve chamber 43 and the lower valve chamber 44 are arranged inside the valve seat 41, and the upper valve chamber 43 communicates with the lower valve chamber 44. The contraction groove 45 is arranged above the upper valve chamber 43. The input flange 46 and the output flange 47 are fixedly connected to the valve seat 41. The input flange 46 communicates with the lower valve chamber 44, and the output flange 47 communicates with the lower valve chamber 44. External fluid is input from the input flange 46 and flows out from the output flange 47. The valve core 42 moves under the drive of the valve stem 1. When the valve is closed, the valve core 42 blocks the communication between the upper valve chamber 43 and the lower valve chamber 44. When the valve is opened, the valve core 42 is located in the contraction groove 45.

[0032] As Figure 5 shown in the figure, a tapered hole 48 is arranged between the upper valve chamber 43 and the lower valve chamber 44. The tapered hole 48 communicates the upper valve chamber 43 and the lower valve chamber 44. A tapered plug 421 is arranged at the bottom of the valve core 42. The contour of the tapered plug 421 is the same as that of the tapered hole 48. A sealing sleeve 422 is arranged on the outer side of the tapered plug 421. When the regulating valve needs to be closed, the tapered plug 421 is plugged into the tapered hole 48, and the sealing sleeve 422 is clamped between the tapered plug 421 and the tapered hole 48 to seal the two.

[0033] As Figure 5 、 Figure 6As shown, the conical plug 421 is provided with an inlet tube 423, a conducting hole 424, and a blocking net 425, and the sealing sleeve 422 is provided with an expansion hole 426. The inlet tube 423 is provided at the bottom of the conical plug 421, and the air inlet end of the inlet tube 423 is fastened to the blocking net 425. One end of the conducting hole 424 is connected to the inlet tube 423, and the other end of the conducting hole 424 is connected to the expansion hole 426. There are multiple groups of expansion holes 426 and conducting holes 424, and the multiple groups of expansion holes 426 and conducting holes 424 are evenly distributed around the inlet tube 423. A micro-sealing ring is provided on the side of the expansion hole 426 away from the conducting hole 424, and the outer edge of the micro-sealing ring slightly exceeds the position of the conducting hole 424. When the conical plug 421 blocks the conical hole 48, the micro-sealing ring is squeezed by the side wall of the conical hole 48, and the micro-sealing ring is sunken, which will block the conducting hole 424. A sealing layer is generally provided on the surface of the valve, and the sealing layer is filled in the valve and the connecting hole when the valve is closed. However, since the wastewater of the power station contains a large amount of waste residue impurities, when the valve is closed, the flow gap is reduced, and the waste residue mixed with sewage flows through the gap, and the flow rate will be relatively increased. The waste residue can easily cause the wear of the sealing layer, and it is difficult to achieve strict sealing of the worn sealing layer. When the conical plug 421 provided in the present invention closes the valve, part of the water flow will flow away from the sealing gap, and part of the water flow will enter the inlet tube 423. The blocking net provided on the inlet tube 423 will filter the impurities, and the filtered fluid will be divided into each conducting hole 424, and then output from each expansion hole 426. The filtered fluid enters the sealing gap from all parts of the sealing sleeve 422, spreads on the surface of the sealing sleeve 422, forms a protective fluid, and prevents the impurities from wearing the surface of the sealing sleeve 422. When the valve is completely closed, the filtered fluid cannot be discharged and will be blocked in the expansion hole. The expansion hole can undergo elastic deformation and increase in volume, and the volume of the sealing sleeve 422 will be enlarged by each expansion hole 426, further improving the sealing effect. The conical plug 421 of the present invention filters and drains part of the sewage and distributes the filtered fluid to the surface of the sealing sleeve 422 to form a protective layer for the sealing sleeve 422, thereby avoiding the wear of the sealing sleeve by impurities in the sealing gap, greatly improving the wear resistance of the sealing sleeve 422 and extending the service life of the regulating valve. On the other hand, after the valve is closed, the pressure of the filtered fluid causes the expansion hole to deform, increasing the volume of the sealing sleeve, further enhancing the sealing pressure at the sealing position and strengthening the sealing effect.

[0034] like Figures 7 - 9As shown in the figure, a diversion unit is provided in the inner wall of the input flange 46. There are multiple groups of diversion units, and the multiple groups of diversion units are evenly distributed around the input flange 46. The diversion unit includes a sliding plate 461, a drainage hole 462, a discharge hole 463, an adjustment cavity 464, a sliding block 465, and a guide block 466. The sliding plate 461 is slidably connected to the inner wall of the input flange 46. The sliding block 465 and the guide block 466 are fixedly connected to the sliding plate 461. The adjustment cavity 464 is embedded in the surface of the inner wall of the input flange 46. A pushing spring is arranged in the adjustment cavity 464. The sliding block 465 is slidably connected to the adjustment cavity 464. One end of the pushing spring is fixedly connected to the side wall of the adjustment cavity 464, and the other end of the pushing spring is fixedly connected to the sliding block 465. The guide block 466 is arranged at one end of the sliding plate 461 close to the valve seat 41. The side of the guide block 466 close to the valve seat 41 is set as a vertical surface, and the side of the guide block 466 away from the valve seat 41 is set as an arc-shaped guide surface. The drainage hole 462 and the discharge hole 463 are also embedded in the inner wall of the input flange 46. The drainage hole 462 is arranged at the end far from the valve seat 41, and the discharge hole 463 is arranged at the end close to the valve seat 41. The ends of the drainage hole 462 and the discharge hole 463 extending into the side wall of the input flange 46 are inclined towards the valve seat 41. A diversion channel is arranged between the drainage hole 462 and the discharge hole 463. Two openings are arranged on the sliding plate 461, and the distance between the openings is equal to the distance between the drainage hole 462 and the discharge hole 463. In the conducting state, the sliding plate 461 seals the drainage hole 462 and the discharge hole 463, and the pipeline fluid flows normally. When the valve is closed, the fluid that originally flowed through the edge gap position at the valve position is blocked, and the fluid flows back along the edge under the action of inertia. The flowing-back fluid impacts on the surface of the guide block 466. The vertical surface of the guide block 466 faces the flowing-back fluid, and a large thrust will be generated. The sliding plate 461 is pushed, and the pushing spring is compressed. After the sliding plate 461 moves, the drainage hole 462, the discharge hole 463, and the openings on the sliding plate 461 are conducted. Since the drainage hole 462 is far from the valve position, when the valve is closed, the subsequent water flow still has a tendency to flow forward. At the drainage hole 462, some of the fluid will flow in, and the diverted fluid is discharged again at the discharge hole 463. The inclined direction of the discharge hole 463 causes the discharged diverted fluid to collide with the oncoming main fluid. The diverted fluid faces the center position of the main fluid, and part of the impact force of the main fluid is consumed by the diverted fluid, and the subsequent water hammer effect will be relatively reduced, and the impact on the valve is reduced. After the water flow returns to calm, the pushing spring pushes the sliding block to reset again, and the sliding plate also resets accordingly. The diversion unit of the present invention will separate multiple strands of diverted fluid from the main pipeline fluid when the valve is closed, and guide the flow direction of the diverted fluid. By borrowing the flow of the diverted fluid, the flow kinetic energy of the main fluid is reduced. And this kind of diversion and blockage only occurs at the moment when the valve is closed and the fluid flows back. On the one hand, it reduces the impact force of the instantaneous water hammer, and on the other hand, it also ensures the smoothness of the flow in the conducting state.

[0035] As Figure 1As shown, the positioning unit 5 includes a position sensor 51 and a scriber 52. The position sensor 51 is provided with two groups. The position sensor 51 is tightly connected to the inner wall of the valve cylinder 3, and the scriber 52 is tightly connected to the valve stem 1. The setting positions of the two groups of position sensors 51 correspond to the positions of the valve stem 1 in the open state and the closed state of the valve, respectively. The valve stem 1 drives the scriber 52 to move. When the scriber 52 passes through the position sensor 51, a position signal is output. The external control device controls the input and output of the airflow according to the signal.

[0036] The working principle of the present invention is as follows: the external air flow pipeline is connected to the compressed air pipeline, and the air intake and exhaust are controlled by the solenoid valve. When the valve needs to be closed, gas is input at the control port 25, the regulating cover 22 is pressed down, and the valve stem 1 is driven to move downward, and the valve is closed. When the valve needs to be opened, gas is discharged from the control port, and the return spring lifts the regulating cover, and the valve is opened. When the regulating cover 22 is moved by pneumatic control, gas is input and output from the bottom of the regulating cover 22 accordingly. The gas passes through the filter plate 246 during input and output. The filter plate 246 is suspended under the fixed ring 242 in a normal state. The input of the airflow will push the movable plate 244 upward, and the output of the airflow will stretch the movable plate 244 downward. After the input and output are completed, the movable plate 244 is pulled and reset by the mounting spring 243. During the reset process, the movable plate 244 vibrates. During the vibration, the filter plate 246 swings up and down. When the filter plate 246 swings up and down, the airflow is guided by the inclined hole array 247, which will generate lateral force. The lateral forces generated by the airflow up and down are in opposite directions. Therefore, each time the regulating valve is started and stopped, the filter plate 246 vibrates in the up and down directions and the left and right directions, and the dust and impurities blocked by the filter screen are vibrated and fall off. The external fluid is input from the input flange 46 and flows out from the output flange 47. The valve core 42 moves under the drive of the valve stem 1. When the valve is closed, the valve core 42 blocks the connection between the upper valve cavity 43 and the lower valve cavity 44. When the valve is opened, the valve core 42 is in the contraction groove 45. When the valve is closed, part of the water will flow away from the sealing gap, and part of the water will enter the inlet tube 423. The barrier net set on the inlet tube 423 will filter impurities, and the filtered fluid will be divided into each conduction hole 424, and then output from each expansion hole 426. The filtered fluid enters the sealing gap from various places of the sealing sleeve 422, spreads on the surface of the sealing sleeve 422, and forms a protective fluid to prevent impurities from wearing the surface of the sealing sleeve 422. When the valve is completely closed, the filtered fluid cannot be discharged and will be blocked in the expansion hole, and the valve is further sealed. When the valve is closed, multiple sub-fluids are separated from the main fluid of the pipeline at the input flange, and the flow direction of the sub-fluids is guided, and the flow kinetic energy of the main fluid is reduced by the flow of the sub-fluids.

[0037] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0038] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A wear-resistant pneumatic control valve for a dusty environment, characterized in that: The pneumatic control valve includes a valve stem (1), an adjusting unit (2), a valve barrel (3), a valve body assembly (4), and a positioning unit (5). One end of the valve stem (1) is connected to the adjusting unit (2), and the other end of the valve stem (1) is connected to the valve body assembly (4). The valve barrel (3) is sleeved outside the valve stem (1). The upper end of the valve barrel (3) is fixedly connected to the adjusting unit (2), and the lower end of the valve barrel (3) is fixedly connected to the valve body assembly (4). The positioning unit (5) is arranged inside the valve barrel (3). One end of the positioning unit (5) is fixedly connected to the valve barrel (3), and the other end of the positioning unit (5) is fixedly connected to the valve stem (1); The valve body assembly (4) includes a valve seat (41), a valve core (42), an upper valve chamber (43), a lower valve chamber (44), a contraction groove (45), an input flange (46), and an output flange (47). The valve seat (41) is fixedly connected to the valve barrel (3). The valve core (42) is fixedly connected to the valve stem (1). The upper valve chamber (43) and the lower valve chamber (44) are arranged inside the valve seat (41). The upper valve chamber (43) is communicated with the lower valve chamber (44). The contraction groove (45) is arranged above the upper valve chamber (43). The input flange (46) and the output flange (47) are fixedly connected to the valve seat (41). The input flange (46) is communicated with the lower valve chamber (44), and the output flange (47) is communicated with the lower valve chamber (44); A flow guiding unit is provided in the inner wall of the input flange (46). There are multiple groups of the flow guiding units, and the multiple groups of flow guiding units are evenly distributed around the input flange (46). The flow guiding unit includes a sliding plate (461), a drainage hole (462), a discharge hole (463), an adjustment cavity (464), a sliding block (465), and a guiding block (466). The sliding plate (461) is slidably connected to the inner wall of the input flange (46). The sliding block (465) and the guiding block (466) are fixedly connected to the sliding plate (461). The adjustment cavity (464) is embedded in the surface of the inner wall of the input flange (46). A pushing spring is arranged in the adjustment cavity (464). The sliding block (465) is slidably connected to the adjustment cavity (464). One end of the pushing spring is fixedly connected to the side wall of the adjustment cavity (464), and the other end of the pushing spring is fixedly connected to the sliding block (465). The guiding block (466) is arranged at one end of the sliding plate (461) close to the valve seat (41). The side of the guiding block (466) close to the valve seat (41) is set as a vertical surface, and the side of the guiding block (466) away from the valve seat (41) is set as an arc-shaped guiding surface. The drainage hole (462) and the discharge hole (463) are also embedded in the inner wall of the input flange (46). The drainage hole (462) is arranged at the end away from the valve seat (41), and the discharge hole (463) is arranged at the end close to the valve seat (41). The ends of the drainage hole (462) and the discharge hole (463) extending into the side wall of the input flange (46) are inclined towards the valve seat (41). A flow guiding channel is arranged between the drainage hole (462) and the discharge hole (463). Two openings are arranged on the sliding plate (461), and the distance between the openings is equal to the distance between the drainage hole (462) and the discharge hole (463).

2. The wear-resistant pneumatic control valve for a dusty environment according to claim 1, characterized in that: The adjustment unit (2) includes a pneumatic cavity (21), an adjustment cover (22), a return spring (23), an air flow port (24), and a control port (25). The pneumatic cavity (21) is fixedly connected to the upper end of the valve barrel (3). The adjustment cover (22) is arranged inside the pneumatic cavity (21). The adjustment cover (22) is slidably connected to the pneumatic cavity (21). The return spring (23) is arranged below the adjustment cover (22). One end of the return spring (23) is fixedly connected to the inner wall of the pneumatic cavity (21), and the other end of the return spring (23) is fixedly connected to the adjustment cover (22). The valve stem (1) is fixedly connected to the adjustment cover (22), and the valve stem (1) is slidably connected to the pneumatic cavity (21). The air flow port (24) is arranged below the pneumatic cavity (21), and the control port (25) is arranged above the pneumatic cavity (21). The control port (25) is connected to an external air flow pipeline.

3. The wear-resistant pneumatic control valve for a dusty environment according to claim 2, characterized in that: The air flow port (24) includes a flow-through cover (241), a fixing ring (242), a mounting spring (243), a movable plate (244), a horizontal groove (245), and a filter plate (246). The flow-through cover (241) is fixedly connected to the bottom of the pneumatic chamber (21), and the top of the flow-through cover (241) is connected to the inside of the pneumatic chamber (21). The fixing ring (242) is fixedly connected to the inner side wall of the flow-through cover (241). The movable plate (244) is slidably connected to the inner side wall of the flow-through cover (241). One end of the mounting spring (243) is fixedly connected to the fixing ring (242), and the other end of the mounting spring (243) is fixedly connected to the movable plate (244). The horizontal groove (245) is provided on the movable plate (244). The filter plate (246) is slidably connected to the horizontal groove (245). An inclined hole array (247) is provided at the middle position of the filter plate (246). The inclined hole array (247) communicates with the upper and lower ends of the filter plate (246). A filter net is provided at one end of the inclined hole array (247) away from the pneumatic chamber (21), and the filter net covers the inclined hole array (247).

4. The wear-resistant pneumatic control valve for a dusty environment according to claim 1, wherein: A conical hole (48) is provided between the upper valve chamber (43) and the lower valve chamber (44). The conical hole (48) communicates the upper valve chamber (43) and the lower valve chamber (44). A conical plug (421) is provided at the bottom of the valve core (42). The contour of the conical plug (421) is the same as that of the conical hole (48). A sealing sleeve (422) is provided on the outer side of the conical plug (421).

5. The wear-resistant pneumatic control valve for a dusty environment according to claim 4, characterized in that: An inflow cylinder (423), a guiding through-hole (424), and a blocking net (425) are provided inside the conical plug (421). An expansion hole (426) is provided inside the sealing sleeve (422). The inflow cylinder (423) is provided at the bottom of the conical plug (421). The air inlet end of the inflow cylinder (423) is fixedly connected to the blocking net (425). One end of the guiding through-hole (424) is connected to the inflow cylinder (423), and the other end of the guiding through-hole (424) is connected to the expansion hole (426). Multiple groups of the expansion holes (426) and the guiding through-holes (424) are provided, and the multiple groups of the expansion holes (426) and the guiding through-holes (424) are evenly distributed around the inflow cylinder (423).

6. The wear-resistant pneumatic control valve for a dusty environment according to claim 1, wherein: The positioning unit (5) includes a position sensor (51) and a sliding piece (52). Two groups of the position sensors (51) are provided, and the position sensors (51) are fixedly connected to the inner side wall of the valve cylinder (3). The sliding piece (52) is fixedly connected to the valve rod (1).

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