High-pressure gate valve capable of being opened and closed with zero friction

Abstract

The high-pressure gate valve comprises a valve body, a valve plate main body and a driving piston, wherein the valve plate main body is arranged in the valve body in a sliding manner; a medium flow channel and a piston cavity which are communicated are formed in the valve body; a movable valve seat is slidably arranged in the medium flow channel; along the flow direction of a medium, the valve plate main body divides the medium runner into a plate front runner and a plate rear runner; one end of the valve plate main body extends into the piston cavity and is provided with a valve plate piston; the valve plate piston divides the piston cavity into a first piston cavity and a second piston cavity; the first piston cavity is formed in the side, close to the valve plate body, of the valve plate piston. A valve plate communicating hole is formed in the valve plate main body to communicate the plate front runner with the second piston cavity; the driving piston is arranged between the first piston cavity and the second piston cavity; the tail end, close to the movable valve seat, of the driving piston is provided with an active pushing-abutting slope facing the movable valve seat. Zero-friction opening and closing of the valve plate body are achieved through the structures such as the driving piston, the valve plate communicating hole and the valve plate piston.

Description

Technical Field

[0001] This invention relates to the field of gate valve technology, and more particularly to a zero-friction high-pressure gate valve. Background Technology

[0002] Gate valves are common shut-off valves used in pipelines.

[0003] The gate valve's function of cutting off media flow relies on the tight fit between the valve plate body and the valve seat. To ensure the reliability of the gate valve's seal, a preload is applied between the valve plate body and the valve seat to ensure a tight seal. During the opening and closing of the gate valve, the valve plate body moves linearly. This tight fit between the valve plate body and the valve seat leads to intense friction between their sealing surfaces. This friction causes rapid wear on the sealing surface of the valve plate body, affecting its sealing performance and increasing resistance during movement. Furthermore, the abrasive generated by friction can contaminate the pipeline medium, impacting the stability of the entire pipeline system. It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a zero-friction high-pressure gate valve to eliminate the friction of the sealing surface of the valve plate body during the movement of the gate valve.

[0005] The technical solution of the present invention is as follows: The zero-friction high-pressure gate valve includes a valve body and a valve plate body slidably disposed within the valve body. A medium flow channel and a piston cavity are connected within the valve body. A movable valve seat is slidably disposed within the medium flow channel along the medium flow direction. The valve plate body divides the medium flow channel into a front flow channel and a rear flow channel. One end of the valve plate body extends into the piston cavity and houses a valve plate piston. The valve plate piston divides the piston cavity into a first piston cavity and a second piston cavity, with the first piston cavity located on the side closest to the valve plate body. A drive piston is also disposed between the first and second piston cavities. An active pushing slope is disposed at the end of the drive piston near the movable valve seat, facing the movable valve seat. The active pushing slope is inclined towards the valve plate body in the direction of the movable valve seat. A parallel driven pushing slope is disposed on the movable valve seat facing the active pushing slope. A valve plate connecting hole is disposed on the valve plate body, connecting the front flow channel and the second piston cavity. Adjusting the on / off state of the valve plate connecting hole adjusts the pressure in the second piston cavity to drive the valve plate piston and the drive piston.

[0006] A valve plate flow channel is provided through the valve plate body along the length of the medium flow channel.

[0007] An overflow connection hole is also provided on the valve body. The overflow connection hole connects the second piston chamber and the flow channel behind the plate. An overflow valve is installed in the overflow connection hole.

[0008] The overflow valve has an overflow channel and contains an overflow valve core and a pressure regulating spring. The upstream side of the overflow connection hole connects to the side of the overflow valve core away from the pressure regulating spring. The overflow valve core blocks the connection hole between the downstream side of the overflow connection hole and the overflow channel.

[0009] A guide rod extending into the second piston chamber is slidably mounted in the overflow channel on the side of the overflow valve core away from the pressure regulating spring. The guide rod has a guide ramp facing the medium flow channel. The guide ramp and the length direction of the overflow channel form an acute angle.

[0010] Along the sliding direction of the valve plate body, a valve cavity communicating with the medium flow channel is also provided on the valve body. A valve stem is movably disposed within the valve cavity, facing the valve plate body.

[0011] Along the sliding direction of the valve plate body, a valve plate guide hole is opened at the end of the valve plate body near the valve stem. The valve stem extends into the valve plate guide hole. The valve plate connecting hole passes through the valve plate guide hole.

[0012] A valve plate and valve block are slidably mounted at the bottom of the valve plate guide hole. A valve block spring is installed between the valve plate and valve block and the bottom of the valve plate guide hole.

[0013] A valve seat elastic element is provided between the movable valve seat and the valve body. The valve seat elastic element is located on the side of the movable valve seat away from the valve plate body.

[0014] A piston seal ring is also fitted onto the drive piston. The piston seal ring fills the gap between the drive piston and the valve plate body. A rod portion that slides onto the drive piston and connects to the valve body is also provided. A limit sleeve is fitted onto the rod portion.

[0015] The beneficial technical effects of the present invention are as follows: (1) The zero-friction high-pressure gate valve of the present invention is provided with a valve plate body and a movable valve seat. When the medium flow channel is disconnected, the valve plate body slides into the medium flow channel to cooperate with the movable valve seat. In addition, a first piston chamber and a second piston chamber are provided, and a valve plate piston and a driving piston are provided. A valve plate connecting hole is provided on the valve plate body to connect the front flow channel and the second piston chamber. When the gate valve is opened, the high-pressure medium in the front flow channel flows into the second piston chamber to increase the pressure in the second piston chamber. The high pressure in the second piston chamber pushes the driving piston and the valve plate body. The movable driving piston drives the movable valve seat away from the valve plate body by actively pushing the inclined surface and passively pushing the inclined surface. The movable valve plate piston drives the valve plate body to move to connect the medium flow channel, and the gate valve opens. At the same time as the gate valve opens, since the movable valve seat moves away from the valve plate body, there is no contact and no friction between the valve plate body and the movable valve seat, avoiding friction and wear on the sealing surface of the valve plate body and the movable valve seat, and greatly improving the service life of the valve plate body. The valve plate body will also not generate wear debris from friction with the movable valve seat to contaminate the flowing medium, improving the stability of the entire pipeline system. When closing the gate valve later, the valve plate connecting hole can be disconnected to prevent the high-pressure medium in the flow channel in front of the plate from flowing into the second piston chamber, so as to reduce the pressure in the second piston chamber.

[0016] (2) Furthermore, a valve plate flow channel is also provided on the valve plate body. The valve plate body does not need to be completely away from the medium flow channel. The medium flow channel can be connected when the valve plate flow channel is aligned with the medium flow channel. That is, when switching the open and closed state of the gate valve, the valve plate piston can always be in the piston cavity, avoiding the need to reinstall the valve plate piston in the piston cavity.

[0017] (3) Furthermore, an overflow communication hole is provided between the second piston chamber and the flow channel behind the plate so that when the valve plate body is closed, the medium in the second piston chamber is discharged into the flow channel behind the plate when the valve plate piston compresses the second piston chamber.

[0018] (4) Further, the valve plate connecting hole passes through the valve plate guide hole, and the valve stem also extends into the valve plate guide hole. When the gate valve is opened, the valve stem moves away from the valve plate body. At this time, the valve plate connecting hole connects the front flow channel and the second piston chamber. The high-pressure medium in the front flow channel flows into the second piston chamber, increasing the medium pressure in the second piston chamber. When the gate valve is closed, the valve stem abuts against and pushes the valve plate body, while blocking the valve plate connecting hole to disconnect the front flow channel and the second piston chamber, facilitating the reduction of the pressure in the second piston chamber. The opening and closing of the valve plate connecting hole is entirely controlled by the action of the valve stem when opening and closing the gate valve, without the need for additional operations, simplifying the use steps of opening and closing the zero-friction high-pressure gate valve. Attached Figure Description

[0019] Figure 1 A vertical cross-sectional view of a zero-friction high-pressure gate valve according to an embodiment of the present disclosure is shown in the closed state.

[0020] Figure 2A partially enlarged view of a zero-friction high-pressure gate valve according to an embodiment of the present disclosure is shown at point A.

[0021] Figure 3 A schematic diagram of the overflow valve in a zero-friction high-pressure gate valve according to an embodiment of the present disclosure is shown.

[0022] Figure 4 A vertical cross-sectional view of a zero-friction high-pressure gate valve according to an embodiment of the present disclosure is shown during the switching process.

[0023] Figure 5 This diagram shows a vertical cross-sectional view of a zero-friction high-pressure gate valve according to an embodiment of the present disclosure, in its open state. Marked in the attached diagram: 1. Valve body; 11. Medium flow channel; 111. Front flow channel; 112. Rear flow channel; 12. Piston cavity; 121. First piston cavity; 122. Second piston cavity; 13. Overflow connecting hole; 14. Valve cavity; 15. Piston cover; 151. Threaded fastener; 152. Elastic support block; 2. Movable valve seat; 21. Valve seat elastic element; 22. Valve seat sealing ring; 23. Driven pushing slope; 24. Valve seat retaining ring; 3. Valve plate body; 31. Valve plate piston; 32. 33. Valve plate flow channel; 331. Valve plate block; 34. Valve plate connecting hole; 35. Valve plate guide hole; 4. Drive piston; 41. Piston sealing ring; 42. Rod; 421. Active pushing slope; 422. Limiting sleeve; 423. Expanding section; 5. Relief valve; 51. Relief valve core; 52. Pressure adjusting spring; 53. Pressure adjusting nut; 54. Relief flow channel; 55. Conducting push rod; 551. Conducting slope; 6. Valve stem; 7. Sealing packing box; 8. Valve cover. Detailed Implementation

[0024] To make the objectives, features, and advantages of this invention more apparent and understandable, please refer to the accompanying drawings. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not intended to limit the implementation conditions of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed in this invention.

[0025] In the description of this invention, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0026] Figure 1 A vertical cross-sectional view of a zero-friction high-pressure gate valve according to an embodiment of the present disclosure is shown in the closed state. Figure 2 A partially enlarged view of point A is shown of a zero-friction high-pressure gate valve according to an embodiment of this disclosure. Please refer to... Figure 1 and Figure 2The zero-friction high-pressure gate valve includes a valve body 1, a valve plate body 3 slidably disposed within the valve body 1, and a drive piston 4. A medium flow channel 11 and a piston cavity 12 are connected within the valve body 1. A movable valve seat 2 is slidably disposed within the medium flow channel 11. Along the medium flow direction, the valve plate body 3 divides the medium flow channel 11 into a front flow channel 111 and a rear flow channel 112. When the medium flow channel 11 is disconnected, the valve plate body 3 slides into the medium flow channel 11 to engage with the movable valve seat 2. One end of the valve plate body 3 extends into the piston cavity 12 and is fitted with a valve plate piston 31. The valve plate piston 31 divides the piston cavity 12 into a first piston cavity 121 and a second piston cavity 122. The first piston cavity 121 is located on the side of the valve plate piston 31 closest to the valve plate body 3. A valve plate connecting hole 34 is provided on the valve plate body 3 to connect the front flow channel 111 and the second piston cavity 122. The drive piston 4 is disposed between the first piston cavity 121 and the second piston cavity 122. An active pushing slope 421 is provided at the end of the drive piston 4 near the movable valve seat 2, facing the movable valve seat 2. The active pushing slope 421 is inclined towards the valve plate body 3 in the direction of the movable valve seat 2. A parallel driven pushing slope 23 is provided on the movable valve seat 2 facing the active pushing slope 421. When the gate valve is opened, the high-pressure medium in the flow channel 111 in front of the valve plate flows into the second piston chamber 122, increasing the pressure in the second piston chamber 122, forming high pressure in the second piston chamber 122. The high pressure in the second piston chamber 122 pushes the drive piston 4 and the valve plate body 3. The driven piston 4, being pushed, drives the movable valve seat 2 away from the valve plate body 3 through the active pushing slope 421 and the driven pushing slope 23. The valve plate body 3 is pushed by the high pressure in the second piston chamber 122 to slide towards the valve chamber, opening the medium flow channel 11, and the gate valve opens. When the gate valve opens, there is no friction between the valve plate body 3 and the movable valve seat 2, avoiding wear and tear on the sealing surface of the valve plate body 3 and the movable valve seat 2, thus significantly extending the service life of the valve plate body 3. Furthermore, the valve plate body 3 will not generate abrasive debris from friction with the movable valve seat 2, contaminating the flowing medium and improving the stability of the entire pipeline system.

[0027] Figure 3 A schematic diagram of the relief valve in a zero-friction high-pressure gate valve according to an embodiment of this disclosure is shown. Please refer to... Figure 1 , Figure 2 and Figure 3 The valve body 1 is also provided with an overflow connection hole 13. The overflow connection hole 13 connects the second piston chamber 122 and the flow channel 112 behind the plate. An overflow valve 5 is provided in the overflow connection hole 13 so that when the valve plate body 3 is closed, the medium in the second piston chamber 122 is discharged into the flow channel 112 behind the plate when the valve plate piston 31 compresses the second piston chamber 122. This avoids the medium pressure in the second piston chamber 122 being too high and hindering the movement of the valve plate piston 31, and maintains the pressure in the second piston chamber 122, ensuring that there is no contact between the valve plate body 3 and the movable valve seat 2.

[0028] Preferably, the overflow valve 5 has an overflow channel 54 and is equipped with an overflow valve core 51 and a pressure regulating spring 52. The upstream of the overflow connecting hole 13 is connected to the side of the overflow valve core 51 away from the pressure regulating spring 52. The overflow valve core 51 blocks the connecting hole between the downstream of the overflow connecting hole 13 and the overflow channel 54. When the valve plate body 3 moves and the gate valve switches from open to closed, the valve plate piston 31 presses the second piston chamber 122, and the medium pressure in the second piston chamber 122 increases. Until the medium pressure in the second piston chamber 122 is greater than the elastic force of the pressure regulating spring 52, the overflow valve core 51 is driven by the pressure to slide towards the side of the pressure regulating spring 52, and the overflow valve core 51 no longer blocks the connecting hole between the downstream of the overflow connecting hole 13 and the overflow channel 54. At this time, the medium in the second piston chamber 122 can be discharged into the flow channel 112 behind the plate along the overflow connecting hole 13.

[0029] More preferably, a guide rod 55 extending into the second piston chamber 122 is slidably disposed within the overflow channel 54 on the side of the overflow valve core 51 away from the pressure regulating spring 52. A guide ramp 551 facing the medium channel 11 is provided on the guide rod 55. The guide ramp 551 and the length direction of the overflow channel 54 are set at an acute angle. When the gate valve switches from open to closed, until the valve plate body 3 moves to the bottom of the second piston chamber 122, the valve plate body 3 pushes the guide rod 55 through the guide ramp 551. The guide rod 55 directly presses and pushes the overflow valve core 51, keeping the two connection holes of the overflow channel 54 and the overflow connecting hole 13 connected. At this time, the medium pressure in the second piston chamber 122 equals the medium pressure in the rear channel 112. The pressure in the second piston chamber 122 is low and no longer pushes the drive piston 4, nor does the drive piston 4 drive the movable valve seat 2. The movable valve seat 2 is pushed against the valve plate body 3 by the valve seat elastic element 21 to seal the gap between the valve plate body 3 and the movable valve seat 2, ensuring that the medium flow channel 11 is disconnected.

[0030] In some embodiments, an adjusting nut 53 is threadedly connected to the overflow valve 5, and an adjusting spring 52 is disposed between the overflow valve core 51 and the adjusting nut 53. By rotating the adjusting nut 53, the distance between the adjusting nut 53 and the body of the overflow valve 5 can be adjusted, thereby adjusting the preload of the adjusting spring 52 to adjust the overflow pressure of the overflow valve 5. This allows the pressure in the second piston chamber 122 to support the driving piston 4 while keeping the pressure as low as possible, thus preventing the pressure in the second piston chamber 122 from hindering the sliding of the valve plate piston 31.

[0031] Please refer to Figure 1 and Figure 2Along the sliding direction of the valve plate body 3, the valve body 1 also has a valve cavity 14 that communicates with the medium flow channel 11. A valve stem 6 is movably disposed in the valve cavity 14 facing the valve plate body 3. In some embodiments, the valve stem 6 can be threadedly connected to the valve body 1. By rotating the valve stem 6, the relative position of the valve stem 6 and the valve body 1 can be adjusted, thereby abutting against or moving away from the valve plate body 3.

[0032] Preferably, a sealing packing box 7 is also provided inside the valve cavity 14. The valve stem 6 passes through and is slidably connected to the sealing packing box 7. Specifically, the sealing packing box 7 is filled with expanded graphite (not shown in the figure) to seal the gap between the valve stem 6 and the sealing packing box 7 and reduce friction. A valve cover 8 is also provided at the opening of the valve cavity 14, and the valve cover 8 and the valve body 1 can be connected by threaded fasteners 151. The valve cover 8 is also further provided with threaded fasteners 151 to connect to the sealing packing box 7, thereby fixing the sealing packing box 7 inside the valve cavity 14.

[0033] Figure 4 A vertical cross-sectional view of a zero-friction high-pressure gate valve according to an embodiment of the present disclosure is shown during the switching process. Figure 5 A schematic diagram of a zero-friction high-pressure gate valve according to an embodiment of this disclosure, showing its vertical cross-sectional structure in the open state, is provided below. Figure 1 , Figure 4 and Figure 5 A valve plate flow channel 32 is provided through the valve plate body 3 along the length of the medium flow channel 11. The valve plate body 3 does not need to be completely away from the medium flow channel 11; the valve plate flow channel 32 can be aligned with the medium flow channel 11 to achieve connectivity. That is, when switching the open and closed states of the gate valve, the valve plate piston 31 can remain within the piston cavity 12, avoiding the need for the valve plate piston 31 to be reinstalled within the piston cavity 12.

[0034] Preferably, a valve plate guide hole 35 is provided at one end of the valve plate body 3 near the valve stem 6 along the sliding direction of the valve plate body 3. The valve stem 6 extends into the valve plate guide hole 35, enhancing the stability of the contact between the valve stem 6 and the valve plate body 3. The valve plate connecting hole 34 passes through the valve plate guide hole 35. After the valve stem 6 is fully extended into the valve plate guide hole 35, the valve plate connecting hole 34 can be disconnected to prevent the medium in the front flow channel 111 from entering the rear flow channel 112 along the valve plate connecting hole, the second piston chamber 122, and the overflow connecting hole 13 when the gate valve is closed, thus preventing medium leakage.

[0035] More preferably, a valve plate block 33 is slidably disposed at the bottom of the valve plate guide hole 35. A valve block spring 331 is disposed between the valve plate block 33 and the bottom of the valve plate guide hole 35. When the valve stem 6 presses against the valve plate block 33, the valve plate block 33 overcomes the elastic force of the valve plate spring and presses against the bottom of the valve plate guide hole 35 to disconnect the valve plate connecting hole 34. When the valve stem 6 moves away from the valve plate body 3, the valve plate spring elastically pushes the valve plate block 33 away from the bottom of the valve plate guide hole 35, and the valve plate connecting hole 34 is connected. The separate valve plate block 33 facilitates ensuring the sealing performance when the valve plate connecting hole 34 is disconnected.

[0036] Please refer to Figure 1 and Figure 2 A valve seat elastic element 21 is provided between the movable valve seat 2 and the valve body 1. The valve seat elastic element 21 is located on the side of the movable valve seat 2 away from the valve plate body 3. When the driving piston 4 moves away from the movable valve seat 2, the valve seat elastic element 21 can push the movable valve seat 2 against the valve plate body 3, sealing the gap between the valve plate body 3 and the movable valve seat 2.

[0037] Preferably, a valve seat sealing ring 22 is also provided between the movable valve seat 2 and the valve body 1. The valve seat sealing ring 22 fills the gap between the movable valve seat 2 and the valve body 1, ensuring the sealing between the movable valve seat 2 and the valve body 1, ensuring that all media pass through the annular movable valve seat 2, and cutting off the media flow channel 11 when the valve plate body 3 and the movable valve seat 2 make sealing contact.

[0038] In some embodiments, a valve seat retaining ring 24 is further fitted onto the movable valve seat 2. The valve seat retaining ring 24 is disposed between the movable valve seat 2 and the valve body 1 to precisely position the positional relationship between the movable valve seat 2 and the valve body 1, and to limit the radial deflection of the movable valve seat 2. Please refer to Figure 1 and Figure 2 A piston sealing ring 41 is also fitted onto the drive piston 4. The piston sealing ring 41 fills the gap between the drive piston 4 and the valve plate body 3, maintaining the pressure difference between the first piston chamber 121 and the second piston chamber 122. A rod portion 42 that is slidably connected to the valve body 1 is also provided on the drive piston 4. A limiting sleeve 422 is fitted onto the rod portion 42. The limiting sleeve 422 reduces the friction between the rod portion 42 and the valve body 1. In addition, the limiting sleeve 422 has a radially protruding enlarged diameter section 423 to limit the relative position of the drive piston 4 and the valve body 1, preventing the drive piston 4 from falling off and completely sliding into the second piston chamber 122.

[0039] Preferably, a piston cover 15 is provided on the valve body 1. The piston cover 15, the valve body 1, and the valve plate piston 31 surround to form a second piston chamber 122. By disassembling and assembling the piston cover 15, the drive piston 4 and the valve plate piston 31 can be easily replaced and maintained. In some embodiments, the piston cover 15 is connected to the valve body 1 by a threaded fastener 151, which facilitates the disassembly and assembly of the piston cover 15.

[0040] More preferably, the piston cover 15 is provided with an elastic support block 152 facing the valve plate piston 31, which flexibly supports the valve plate piston 31. In addition, when the gate valve is opened, after the valve stem 6 moves away from the valve plate body 3, the elastic support block 152 can push the valve plate body 3, so that the valve plate body 3 no longer abuts against the conduction rod 55. The medium in the pressure regulating spring 52 and the overflow channel 54 pushes the conduction rod 55 to reset, and correspondingly the overflow valve core 51 resets to block the communication hole between the downstream of the overflow communication hole 13 and the overflow channel 54, so as to increase the pressure of the medium in the second piston chamber 122 and drive the movable valve seat 2 and the valve plate body 3.

[0041] The specific workflow of this invention is as follows: When the gate valve switches from closed to open, the operator moves the valve stem 6 away from the valve plate body 3, and the valve stem 6 no longer presses against the valve plate block 33. The valve block spring 331 pushes the valve plate block 33 away from the valve plate connecting hole 34. The valve plate connecting hole 34 connects the front flow channel 111 and the second piston chamber 122. The pressure in the second piston chamber 122 increases to a high-pressure state, pushing the drive piston 4 and the valve plate piston 31. The drive piston 4 is pushed towards the movable valve seat 2, and through the driven pushing inclined surface 23 and the active pushing inclined surface 421, it drives the movable valve seat 2 to move away from the valve plate body 3, achieving zero friction when the valve plate body 3 moves. At the same time, the first piston chamber 121 connects the front flow channel 111 and the rear flow channel 112, and the pressure in the first piston chamber 121 is less than the pressure in the second piston chamber 122. The valve plate body 3 is pushed towards the valve stem 6. Until the valve plate flow channel 32 is fully connected to the front flow channel 111 and the rear flow channel 112, the pressure in the front flow channel 111 and the pressure in the rear flow channel 112 are close. At this time, the pressure between the first piston chamber 121 and the second piston chamber 122 is also close. The valve plate body 3 no longer moves, and the gate valve opens.

[0042] When the gate valve switches from the open to the closed state, the operator moves the valve stem 6 towards the side closer to the valve plate body 3. The valve plate then presses against and pushes the valve plate block 33. The valve plate block 33 overcomes the elastic force of the valve block spring 331 and presses against the bottom of the valve plate guide hole 35, disconnecting the valve plate connecting hole 34. Continuing to move the valve stem 6, it pushes the valve plate body 3 towards the side closer to the piston cover 15. The valve plate piston 31 continuously compresses the second piston chamber 122, maintaining high pressure within it. The high pressure in the second piston chamber 122 supports the drive piston 4, causing it to move the movable valve seat 2 away from the valve plate body 3, preventing friction between the valve plate body 3 and the movable valve seat 2 during movement. During this process, the overflow valve 5 continuously releases pressure from the second piston chamber 122, maintaining only the pressure supporting the drive piston 4. Until the valve plate piston 31 abuts against the elastic support block 152, the valve plate piston 31 also abuts against the push rod 55 along the guide slope 551. The guide rod 55 pushes the overflow valve core 51, keeping the overflow valve 5 open. At this time, the flow channel 112 behind the connecting plate of the second valve chamber 14 is in a low-pressure state, and the drive piston 4 no longer abuts against the movable valve seat 2. Under the action of the valve seat elastic element 21, the movable valve seat 2 abuts against the valve plate body 3 to ensure sealing, and the gate valve is closed.

[0043] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0044] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A zero-friction high-pressure gate valve, characterized in that, The zero-friction high-pressure gate valve includes a valve body and a valve plate body slidably disposed within the valve body. A medium flow channel and a piston cavity are connected within the valve body. A movable valve seat is slidably disposed within the medium flow channel along the medium flow direction. The valve plate body divides the medium flow channel into a front flow channel and a rear flow channel. One end of the valve plate body extends into the piston cavity and is fitted with a valve plate piston. The valve plate piston divides the piston cavity into a first piston cavity and a second piston cavity, with the first piston cavity located on the side closest to the valve plate body. A driving piston is also disposed between the first piston cavity and the second piston cavity. An active pushing slope is disposed at the end of the driving piston near the movable valve seat, facing the movable valve seat. The active pushing slope is inclined towards the valve plate body in the direction of the movable valve seat. A parallel driven pushing slope is disposed on the movable valve seat facing the active pushing slope. A valve plate connecting hole is provided on the valve plate body, connecting the front flow channel and the second piston cavity. Adjusting the on / off state of the valve plate connecting hole adjusts the pressure in the second piston cavity to drive the valve plate piston and the driving piston.

2. The zero-friction high-pressure gate valve as described in claim 1, characterized in that: A valve plate flow channel is provided through the valve plate body along the length direction of the medium flow channel.

3. The zero-friction high-pressure gate valve as described in claim 1, characterized in that: The valve body is also provided with an overflow connection hole; the overflow connection hole connects the second piston chamber and the flow channel behind the plate; an overflow valve is provided in the overflow connection hole.

4. The zero-friction high-pressure gate valve as described in claim 3, characterized in that: The overflow valve has an overflow channel and an overflow valve core and a pressure regulating spring inside; the upstream of the overflow connecting hole is connected to the side of the overflow valve core away from the pressure regulating spring; the overflow valve core blocks the connecting hole between the downstream of the overflow connecting hole and the overflow channel.

5. The zero-friction high-pressure gate valve as described in claim 4, characterized in that: A guide rod extending into the second piston chamber is slidably disposed in the overflow channel on the side of the overflow valve core away from the pressure regulating spring; a guide ramp is disposed on the guide rod facing the medium flow channel; the guide ramp and the length direction of the overflow channel are arranged at an acute angle.

6. The zero-friction high-pressure gate valve as described in claim 1, characterized in that: Along the sliding direction of the valve plate body, the valve body is also provided with a valve cavity that communicates with the medium flow channel; a valve stem is movably disposed in the valve cavity and faces the valve plate body.

7. The zero-friction high-pressure gate valve as described in claim 6, characterized in that: Along the sliding direction of the valve plate body, a valve plate guide hole is opened at one end of the valve plate body near the valve stem; the valve stem extends into the valve plate guide hole; the valve plate connecting hole passes through the valve plate guide hole.

8. The zero-friction high-pressure gate valve as described in claim 7, characterized in that: A valve plate block is slidably disposed at the bottom of the valve plate guide hole; a valve block spring is disposed between the valve plate block and the bottom of the valve plate guide hole.

9. The zero-friction high-pressure gate valve as described in claim 1, characterized in that: A valve seat elastic element is provided between the movable valve seat and the valve body; the valve seat elastic element is located on the side of the movable valve seat away from the valve plate body.

10. The zero-friction high-pressure gate valve as described in claim 1, characterized in that: The driving piston is also fitted with a piston sealing ring; the piston sealing ring fills the gap between the driving piston and the valve plate body; the driving piston is also provided with a rod portion that slides to connect to the valve body; a limiting sleeve is fitted on the rod portion.

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