Hard sealing butterfly valve

Abstract

The invention relates to the technical field of valves, in particular to a hard sealing butterfly valve which comprises a valve body, a valve rod and a valve plate, and a water hammer preventing mechanism is arranged in the valve plate. The water hammer preventing mechanism comprises a buffering runner, a weight, a buffering spring and a piston plate, the two ends of the buffering runner communicate with the front end face and the rear end face of the valve plate, the weight is slidably embedded in the runner, and the spring is located between the weight and the piston plate. The valve plate is divided into a positioning plate and a rotating plate, the front end of the rotating plate is wavy, the center ends of the buffer flow channels intersect to form a communication cavity, and the edge ends of the buffer flow channels are provided with electromagnetic switches and micro-expansion sections. The vibration frequency is adjusted through displacement of the heavy block, the resonance risk is reduced, impact energy is absorbed through the spring, the sealing performance is optimized through the micro-expansion section, and meanwhile uniform abrasion is achieved through rotation of the rotating plate. The water hammer resistance and the sealing performance are remarkably improved, the service life is prolonged, and the important practical value is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of valves, and particularly to a hard-sealed butterfly valve. Background Art

[0002] A butterfly valve is a widely used fluid control device that realizes the on-off or flow regulation of fluids through the rotation of a valve plate. Hard-sealed butterfly valves are particularly common in industrial pipeline systems due to their excellent high-temperature resistance, high-pressure resistance, and wear resistance. However, existing hard-sealed butterfly valves have certain limitations in dealing with water hammer impacts, mainly including the following aspects: 1. The impact of water hammer on the structure is relatively large. When a water hammer phenomenon occurs in the pipeline, the pressure wave will cause a violent impact on the valve plate, which may cause the vibration frequency of the valve plate to be close to the frequency of the pressure wave, thereby triggering resonance problems and increasing the risk of structural fatigue. In addition, traditional butterfly valves lack an effective energy absorption mechanism and are difficult to significantly reduce the destructive impact brought by water hammer.

[0003] 2. The sealing performance is limited by the structural design. When the butterfly valve is in the closed state, if the fluid pressure is high, the valve plate may undergo slight deformation due to uneven force, resulting in a decrease in the sealing effect. Although some designs improve the sealing performance by adding sealing rings, during long-term use, the sealing rings are prone to wear, which in turn affects the overall sealing ability of the valve.

[0004] 3. The problem of uneven wear at the contact position between the valve plate and the valve body is relatively prominent. The valve plate of a traditional butterfly valve is usually fixedly connected to the valve stem, and under the action of water hammer, the stress cannot be effectively dispersed, easily leading to severe local wear at the contact surface between the valve plate and the valve body, further affecting the sealing performance and service life.

[0005] The invention patent with the publication number CN114941719B discloses an anti-resonance large-diameter triple-eccentric metal hard-sealed butterfly valve, which relates to the technical field of butterfly valves and includes: an outer cylinder, a base, a top cover, an oil cup, and an anti-vibration cylinder; a clamping groove is provided on the inner wall of the outer cylinder, and two groups of grooves are provided at the left and right ends of the outer cylinder, and sealing rings are installed in the grooves; the base is bolted to the upper end of the outer cylinder, and a worm gear shaft is pivotally connected to the base, and the worm gear on the worm gear shaft is one-fourth of a common worm gear; by loosening the butterfly nut to adjust the position of the cleaning roller, the cleaning roller is brought into contact with the worm, and when the worm is rotated, the cleaning roller can brush the dust on the worm to prevent the worm from being covered with dust and causing difficulty in worm rotation; when the sealing plate is opened and closed, a water hammer effect will occur. When the shock wave is introduced into the buffer cylinder, the shock wave acts on the piston, and the piston will move upward, which can effectively eliminate the irregular shock wave oscillation and prevent the butterfly valve from resonating with the water flow and generating noise during use. However, this solution mainly focuses on pressure relief in a single direction, does not fully consider the regulating effect of the dynamic change of the overall mass distribution of the valve plate on the vibration frequency, and does not take into account the problem of uniform wear of the sealing surface. Summary of the Invention

[0006] The object of the present invention is to overcome the deficiencies in the prior art, solve or at least alleviate the problems of resonance, decline in sealing performance and uneven wear of the valve plate that are easily caused when a hard-sealed butterfly valve responds to water hammer shock, and provide a hard-sealed butterfly valve with the ability to resist water hammer and the characteristics of uniform wear.

[0007] To achieve the above object, the present invention provides the following technical solutions: a hard-sealed butterfly valve, including a valve body, a valve stem and a valve plate. The rear end face of the valve plate is fixedly sleeved on the valve stem. The valve plate is provided with a water hammer prevention mechanism. The water hammer prevention mechanism includes a buffer flow channel, a weight, a buffer spring and a piston plate. The buffer flow channel is arranged radially along the valve plate. Both ends of the buffer flow channel communicate with the front end face of the valve plate. The weight is slidably arranged in the buffer flow channel. The two piston plates are respectively located at both ends of the weight. The piston plates are hermetically slidably arranged in the buffer flow channel. The two buffer springs are respectively located between the two piston plates and both ends of the weight.

[0008] To further implement the present invention, the following technical solutions can be preferably selected: Preferably, a plurality of the water hammer prevention mechanisms are circumferentially and evenly distributed. One end of the buffer flow channel is located at the edge of the valve plate, and the other end is located at the center of the valve plate. One ends of the buffer flow channels of all the water hammer prevention mechanisms that are located at the center of the valve plate coincide and communicate with each other.

[0009] Preferably, a micro-expansion section is arranged at one end of the buffer flow channel located at the edge of the valve plate. One end of the micro-expansion section communicates with the buffer flow channel, and the other end faces the sealing position between the valve plate and the valve body.

[0010] Preferably, a metal sealing ring is detachably arranged inside the valve body. The metal sealing ring and the valve plate form a sealing pair. The sealing surface of the metal sealing ring is a conical inclined surface.

[0011] Preferably, the valve plate includes a positioning plate and a rotating plate. The rear end of the positioning plate is fixedly sleeved on the valve stem. The rotating plate is rotatably arranged at the front end of the positioning plate. The water hammer prevention mechanism is located inside the rotating plate.

[0012] Preferably, the front end face of the rotating plate is wavy. The connection position between the buffer flow channel and the rotating plate is located at the bottom of the wave valley of the front end face of the rotating plate.

[0013] Preferably, the wavy front end face of the rotating plate is designed as a continuous sine curve shape, and the height difference between the wave crest and the wave valley is 2 mm to 5 mm.

[0014] Preferably, a rotating shaft is arranged at the center of the rear end of the rotating plate. The rotating shaft is rotatably sleeved at the center of the positioning plate. The diameter value of the rotating shaft is greater than the diameter value of the connection position between one end of the buffer flow channel located at the center of the rotating plate and the rotating plate.

[0015] The beneficial effects of the present invention are: The present invention sets a water hammer prevention mechanism inside the valve plate. By utilizing the displacement of the weight in the buffer flow channel under the impact of water hammer, the mass distribution of the valve plate is adjusted, thereby changing the vibration frequency of the valve plate, reducing the risk of resonance with the pressure wave, and reducing structural fatigue. The setting of the buffer spring converts part of the impact energy into mechanical kinetic energy, playing a role similar to a shock absorber and effectively alleviating the destructive impact of water hammer on the valve plate.

[0016] The present invention controls the connection state of the buffer flow channel through an electromagnetic switch. When the butterfly valve is in the closed state, the edge end of the buffer flow channel is closed, and the fluid pressure is used to slightly expand the valve plate, thereby improving the sealing effect. The design of the slightly expanding section enhances the expansion effect of the fluid on the valve plate and further optimizes the sealing performance.

[0017] The present invention divides the valve plate into a positioning plate and a rotating plate. The rotating plate rotates under the impact of water hammer, changing its contact position with the valve body, making the wear of the sealing surface of the rotating plate more uniform, and extending the service life of the valve. The wavy design on the front end surface of the rotating plate reduces the impact of fluid impact on the overall structure of the rotating plate and improves the impact resistance of the valve plate. Description of the Drawings

[0018] Figure 1 is the structural schematic diagram of the present invention.

[0019] Figure 2 is the front view of the present invention.

[0020] Figure 3 is the Figure 2 cross-sectional view taken along line A-A in the present invention.

[0021] Figure 4 is the Figure 2 cross-sectional view taken along line B-B in the present invention.

[0022] Figure 5 is the Figure 3 cross-sectional view taken along line C-C in the present invention.

[0023] Figure 6 is the structural schematic diagram of the rotating plate of the present invention.

[0024] The reference numerals are: 1-valve body; 2-valve stem; 3-valve plate; 4-buffer flow channel; 5-weight; 6-buffer spring; 7-piston plate; 8-slightly expanding section; 9-metal sealing ring; 10-rotating shaft; 31-positioning plate; 32-rotating plate. Detailed Embodiments

[0025] In the description of the present invention, it should also be noted that, unless otherwise clearly specified and defined, the terms "set", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] 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 skilled in the art without creative efforts shall fall within the protection scope of the present invention.

[0027] Embodiment 1 The water hammer impact has a greater impact on the structure. When a water hammer phenomenon occurs in the pipeline, the pressure wave will cause a violent impact on the valve plate 3, which may cause the vibration frequency of the valve plate 3 to be close to the pressure wave frequency, thereby triggering a resonance problem and increasing the risk of structural fatigue. In addition, the traditional butterfly valve lacks an effective energy absorption mechanism and is difficult to significantly reduce the destructive impact brought by the water hammer impact.

[0028] Referring to Figures 1 to 5 , this embodiment discloses a hard-sealed butterfly valve, which includes a valve body 1, a valve stem 2, and a valve plate 3. The rear end face of the valve plate 3 is fixedly sleeved on the valve stem 2. The valve plate 3 is provided with a water hammer prevention mechanism, and the water hammer prevention mechanism includes a buffer flow channel 4, a weight 5, a buffer spring 6, and a piston plate 7. The water hammer prevention mechanism is composed of the buffer flow channel 4, the weight 5, the buffer spring 6, and the piston plate 7. The buffer flow channel 4 is arranged radially along the valve plate 3, and both ends are communicated to the front end face of the valve plate 3 to form a two-way fluid channel. The weight 5 is slidably arranged in the buffer flow channel 4, and both ends are connected to the piston plate 7 through the buffer spring 6. The piston plate 7 seals and slides in the flow channel to prevent fluid leakage and at the same time transmits the impact force to the spring. A plurality of water hammer prevention mechanisms are evenly distributed along the circumference of the valve plate 3, and the central ends of their buffer flow channels 4 coincide and communicate to form a concentrated buffer area. This design can evenly disperse the water hammer impact energy and improve the compressive stability.

[0029] A metal sealing ring 9 is detachably arranged inside the valve body 1. The metal sealing ring 9 and the valve plate 3 form a sealing pair, and the sealing surface of the metal sealing ring 9 is a conical inclined surface.

[0030] Inside the valve body 1, a metal sealing ring 9 is provided. The metal sealing ring 9 is detachably installed on the inner wall of the valve body 1 through a threaded or card slot structure. The metal sealing ring 9 and the valve plate 3 form a sealing pair. The sealing surface of the metal sealing ring 9 is designed as a conical inclined plane, and the material is stainless steel or cemented carbide, and is hardened to improve wear resistance. The conical inclined plane design of the metal sealing ring 9 increases the sealing contact area and optimizes the sealing performance.

[0031] When a water hammer impact occurs, the fluid pressure is transmitted to the weight 5 through the buffer flow channel 4. The weight 5 moves along the buffer flow channel 4 under the drive of the pressure difference. The displacement of the weight 5 compresses the buffer spring 6, converting part of the impact energy into mechanical kinetic energy, playing a role similar to a shock absorption device. At the same time, the movement of the weight 5 changes the mass distribution of the valve plate 3, adjusts the vibration frequency of the valve plate 3, reduces the risk of resonance with the pressure wave, and thus reduces structural fatigue.

[0032] Embodiment 2 The sealing performance of the butterfly valve is limited by the structural design. In the closed state, if the fluid pressure is high, the valve plate 3 may have slight deformation due to uneven force, resulting in a decrease in the sealing effect. Although some designs improve the sealing performance by adding sealing rings, during long-term use, the sealing rings are prone to wear, which in turn affects the overall sealing ability of the valve.

[0033] Referring to Figure 4 In this embodiment, an electromagnetic switch is installed at the inlet of the buffer flow channel 4 at the edge of the valve plate 3. When the butterfly valve is closed, the electromagnetic switch is closed, blocking the fluid outflow in the buffer flow channel 4; when the butterfly valve is opened or to be opened, the electromagnetic switch is opened, allowing the fluid in the buffer flow channel 4 to flow out. One end of the buffer flow channel 4 located at the edge of the valve plate 3 is provided with a micro-expansion section 8. One end of the micro-expansion section 8 is connected to the buffer flow channel 4, and the other end faces the sealing part of the valve plate 3 and the valve body 1.

[0034] When the butterfly valve is in the closed state, the electromagnetic switch is closed, the edge end of the buffer flow channel 4 is closed, and the fluid pressure is transmitted to the micro-expansion section 8 through the buffer flow channel 4. The micro-expansion section 8 causes the fluid to have an expansion effect on the valve plate 3, thereby enhancing the sealing effect between the valve plate 3 and the metal sealing ring 9. When the butterfly valve is opened or to be opened, the electromagnetic switch is opened, the buffer flow channel 4 is communicated with the outside, and the expansion effect of the valve plate 3 ends, facilitating the rotation of the valve plate 3.

[0035] By controlling the connection state of the buffer flow channel 4 through the electromagnetic switch, the edge end of the buffer flow channel 4 is closed in the closed state of the butterfly valve, and the fluid pressure is used to slightly expand the valve plate 3, thereby improving the sealing effect. The design of the micro-expansion section 8 enhances the expansion effect of the fluid on the valve plate 3 and further optimizes the sealing performance.

[0036] Embodiment 3 The problem of uneven wear at the contact position between the valve plate 3 and the valve body 1 is relatively prominent. In traditional butterfly valves, the valve plate 3 is usually fixedly connected to the valve stem 2. Under water hammer impact, stress cannot be effectively dispersed, easily leading to severe local wear on the contact surface between the valve plate 3 and the valve body 1, further affecting the sealing performance and service life.

[0037] Referring to Figure 3 and Figure 6 In this embodiment, the valve plate 3 includes a positioning plate 31 and a rotating plate 32. The rear end of the positioning plate 31 is fixedly sleeved on the valve stem 2, and the rotating plate 32 is rotatably arranged at the front end of the positioning plate 31. The water hammer prevention mechanism is located inside the rotating plate 32.

[0038] The front end face of the rotating plate 32 is wavy. The connection between the buffer flow channel 4 and the rotating plate 32 is located at the bottom of the wave valley on the front end face of the rotating plate 32. The wavy front end face of the rotating plate 32 is designed as a continuous sine curve shape, and the height difference between the wave peak and the wave valley is 2 mm to 5 mm. This structure can break up the laminar flow state of the fluid, reduce the direct impact force. At the same time, the buffer flow channel 4 is connected at the wave valley, guiding the fluid to efficiently enter the buffer flow channel 4, and at the same time making it easier for the rotating plate 32 to rotate, further reducing the impact of water hammer.

[0039] A rotating shaft 10 is provided at the center of the rear end of the rotating plate 32. The rotating shaft 10 is rotatably sleeved at the center of the positioning plate 31. The diameter value of the rotating shaft 10 is greater than the diameter value of the connection between the end of the buffer flow channel 4 at the center of the rotating plate 32 and the rotating plate 32.

[0040] The rotating plate 32 rotates under water hammer impact, changing its contact position with the valve body 1. Since the front end face of the rotating plate 32 is designed to be wavy and the connection between the buffer flow channel 4 and the rotating plate 32 is located at the bottom of the wave valley, this design effectively reduces the impact of fluid impact on the overall structure of the rotating plate 32. At the same time, the rotating characteristics of the rotating plate 32 make the wear of its sealing surface more uniform, avoiding the problem of sealing performance degradation caused by severe local wear in traditional butterfly valves. The sine curve design of the wavy front end face further optimizes the dispersion effect of fluid impact force, improving the impact resistance of the valve plate 3.

[0041] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered within the protection scope of the present invention.

Claims

1. A hard-sealed butterfly valve, comprising a valve body (1), a valve stem (2) and a valve plate (3), the rear end face of the valve plate (3) is fixedly sleeved on the valve stem (2), and is characterized in that, The valve plate (3) is provided with a water hammer prevention mechanism, and the water hammer prevention mechanism includes a buffer flow channel (4), a weight (5), a buffer spring (6) and a piston plate (7). The buffer flow channel (4) is arranged along the radial direction of the valve plate (3), and both ends of the buffer flow channel (4) communicate with the front end face of the valve plate (3). The weight (5) is slidably arranged in the buffer flow channel (4), and the two piston plates (7) are respectively located at both ends of the weight (5). The piston plate (7) is hermetically and slidably arranged in the buffer flow channel (4), and the two buffer springs (6) are respectively located between both ends of the two piston plates (7) and the weight (5).

2. The hard-sealed butterfly valve according to claim 1, wherein A plurality of the water hammer prevention mechanisms are circumferentially and uniformly arranged. One end of the buffer flow channel (4) is located at the edge of the valve plate (3), and the other end is located at the center of the valve plate (3). One ends of the buffer flow channels (4) of all the water hammer prevention mechanisms coincide and communicate with each other at the center of the valve plate (3).

3. The hard-sealed butterfly valve according to claim 1, characterized in that, One end of the buffer flow channel (4) located at the edge of the valve plate (3) is provided with a micro-expansion section (8). One end of the micro-expansion section (8) communicates with the buffer flow channel (4), and the other end faces the sealing part between the valve plate (3) and the valve body (1).

4. The hard-sealed butterfly valve according to claim 1, characterized in that, A metal sealing ring (9) is detachably arranged inside the valve body (1). The metal sealing ring (9) and the valve plate (3) form a sealing pair, and the sealing surface of the metal sealing ring (9) is a conical inclined surface.

5. The hard-sealed butterfly valve according to any one of claims 1-4, characterized in that, The valve plate (3) includes a positioning plate (31) and a rotating plate (32). The rear end of the positioning plate (31) is fixedly sleeved on the valve rod (2), and the rotating plate (32) is rotatably arranged at the front end of the positioning plate (31). The water hammer prevention mechanism is located inside the rotating plate (32).

6. The hard-sealed butterfly valve according to claim 5, characterized in that, The front end face of the rotating plate (32) is wavy, and the connection part of the buffer flow channel (4) and the rotating plate (32) is located at the bottom of the wave valley of the front end face of the rotating plate (32).

7. The hard-sealed butterfly valve according to claim 6, characterized in that, The wavy front end face of the rotating plate (32) (13) is designed as a continuous sine curve shape, and the height difference between the wave crest and the wave valley is 2 mm to 5 mm.

8. The hard-sealed butterfly valve according to claim 5, characterized in that, A rotating shaft (10) is arranged at the center of the rear end of the rotating plate (32). The rotating shaft (10) is rotatably sleeved at the center of the positioning plate (31), and the diameter value of the rotating shaft (10) is greater than the diameter value of the connection part between one end of the buffer flow channel (4) located at the center of the rotating plate (32) and the rotating plate (32).

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