Self-cleaning semi-ball valve

Abstract

The invention discloses a self-cleaning semi-ball valve, relates to the technical field of semi-ball valves, and solves the problem that medium residues and accumulation are easy to occur in the semi-ball valve. The hemisphere is horizontally installed in the valve cavity, the valve cavity is divided into a valve cavity upper half part and a valve cavity lower half part along the horizontal plane of the center of the valve cavity, a box body is installed on the horizontal side of the valve body, and the valve rod is vertically inserted into the box body in a penetrating mode and is in gear transmission connection with the hemisphere. The valve rod moves in the axial direction and drives the hemisphere to rotate from the horizontal plane to the upper half portion of the valve cavity through gear transmission so as to open the valve. The hemispheroid is rotationally opened and closed in the vertical direction, when the valve is opened, the hemispheroid is located on the upper half portion of the valve cavity, the lower half portion of the valve cavity achieves the self-cleaning function by means of fluid pressure, and medium residue, crystallization and coking material accumulation are effectively prevented; in addition, direct contact between the hemispheroid and accumulated media on the lower half portion of the valve cavity is avoided through the rotary opening and closing mode of the hemispheroid in the vertical direction, and the jamming problem caused by medium residues of a traditional hemisphere valve is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of hemispherical valves, in particular to a self-cleaning hemispherical valve. Background Art

[0002] Traditional hemispherical valves usually use a single hemispherical body as the opening and closing part, and control the flow of fluids by horizontal rotation of the hemispherical body. However, when dealing with media under harsh working conditions such as high temperature, high pressure, corrosiveness or containing solid particles, traditional hemispherical valves are prone to problems such as residual accumulation of media and opening and closing obstructions. These problems will not only lead to system failures, but may also cause environmental pollution and economic losses.

[0003] The Chinese utility model of the prior art discloses CN211288919U, a top-mounted C-type hemispherical ball valve with a drain port, which is mainly provided with a drain port at the bottom of the valve body, and a plug with a detachable sealing installation is provided in the drain port; therefore, when the medium is passed into the valve body, the plug can ensure the sealing of the drain port, and the accumulated impurities in the valve cavity can be cleaned by removing the plug. However, under the working condition of processing medium that is easy to crystallize and coke, the operation of discharging crystals and coke through a small drain port is very inconvenient, and frequent disassembly and cleaning are required, which increases the maintenance workload; and the drain port is likely to become a new leakage point, affecting the sealing performance of the valve. In addition, when the hemisphere is opened and closed by horizontal rotation, the hemisphere and the accumulated medium in the valve cavity hinder each other, resulting in the hemisphere opening and closing being restricted and the torque increasing, causing the valve to be stuck, affecting the normal opening and closing function of the valve. Summary of the invention

[0004] Purpose of the present invention: In order to overcome the defects of the prior art, the present invention provides a self-cleaning hemispherical valve to solve the problems of residual medium accumulation, opening and closing obstruction, etc. in the hemispherical valve.

[0005] The technical solution of the present invention includes a hemisphere, a valve body, a valve stem and a valve seat. The valve body is provided with a valve cavity. The two sides of the valve cavity are provided with an inlet flow channel and an outlet flow channel. The hemisphere is horizontally installed in the valve cavity. The valve cavity is divided into an upper half and a lower half of the valve cavity along a horizontal plane at its center. A box body is installed on the horizontal side of the valve body. The valve stem is vertically inserted into the box body and is connected to the hemisphere gear transmission. The valve stem moves along its axial direction and drives the hemisphere to rotate from the horizontal plane to the upper half of the valve cavity through the gear transmission to open the valve.

[0006] By adopting the above technical scheme, the valve is opened and closed by vertically rotating the hemisphere. When the valve is opened, the hemisphere is in the upper part of the valve cavity, and the lower part of the valve cavity realizes a self-cleaning function with the help of fluid pressure, which effectively prevents the residue, crystallization and accumulation of coke from the medium, and reduces the maintenance frequency and workload of the valve. Moreover, the vertically rotating opening and closing method of the hemisphere avoids the direct contact between the hemisphere and the medium accumulated in the lower part of the valve cavity, reduces the opening and closing resistance, and avoids the jamming problem of the traditional hemisphere valve caused by the residue of the medium, thereby improving the opening and closing performance and reliability of the valve, and is very suitable for use in harsh working conditions. In addition, in order to adapt to the rotation mode of the hemisphere, the operation mode of the valve is changed from the traditional angular stroke to the straight stroke, and the rotation opening and closing of the hemisphere is realized by the cooperation of the rack and gear on the valve stem, which makes the operation easier and suitable for occasions with limited space.

[0007] In a possible design, there are two hemispheres which are arranged on both sides of the valve stem. The two hemispheres are arranged in mirror symmetry and respectively form an opening and closing switch with the inlet flow channel and the outlet flow channel. The valve stem is respectively connected to the two hemispheres through gear transmission.

[0008] With the above design, the two hemispheres form an opening and closing switch with the inlet flow channel and the outlet flow channel respectively, realizing double sealing of the inlet and outlet, and the sealing effect is better. At the same time, the two hemispheres arranged in a mirror-symmetrical manner make the valve more balanced in force during the opening and closing process, avoiding the unbalanced load phenomenon that may occur in a single hemisphere during the opening and closing process.

[0009] In a possible design, the valve stem has rack portions at radially opposite sides, and a gear shaft is fixed at the rotation center of one end of each hemisphere, and the gear shaft and the rack portion are meshed.

[0010] The above design is equivalent to meshing the two rack parts on the valve stem with the gear shafts on the two hemispheres, ensuring that the two hemispheres move synchronously during the opening and closing process, ensuring the coordination of the valve when opening and closing, and the force is more balanced, avoiding the unbalanced load phenomenon caused by uneven force on one side. In addition, compared with the traditional direct rotation transmission method, the gear rack transmission method has higher transmission accuracy, can transmit torque more effectively, and is more suitable for the vertical rotation of the hemisphere, ensuring the stable rotation of the hemisphere.

[0011] In a possible design, the hemisphere has one and is arranged on one side close to the inlet flow channel, the valve stem has a rack portion, and a gear shaft is fixed at the rotation center position of one end of the hemisphere, and the gear shaft and the rack portion are meshed.

[0012] By adopting the above design, only one hemisphere is used, which simplifies the internal structure of the valve, reduces the number of parts, reduces the manufacturing cost, reduces the burden of opening and closing the valve stem, and transmits torque more effectively; from the perspective of valve volume, a single hemisphere reduces the overall volume of the valve, saves installation space, and is particularly suitable for occasions with limited space, thereby increasing the applicability of the valve.

[0013] In a possible design, the bottom of the lower half of the valve cavity is in a concave curved shape.

[0014] With the above design, the concave curved surface shape makes the fluid flow in the lower half of the valve cavity smoother, reduces the dead angle area in the lower half of the valve cavity, more effectively removes the residual medium in the valve cavity, further prevents the residue and accumulation of the medium in the valve cavity, and reduces the occurrence of crystallization, coking and the like.

[0015] In a possible design, a limiting protrusion is provided at the bottom of the lower half of the valve cavity, and the limiting protrusion is abutted against the hemispherical body in the closed position for limiting position.

[0016] The above design ensures that the hemisphere can stop accurately at the predetermined position when in the closed position, avoiding excessive rotation or position deviation of the hemisphere, which is beneficial to improving the closing accuracy and ensuring the sealing effect; in addition, the limiting protrusion can support the hemisphere, reduce the force on the rack part of the valve stem, and reduce the wear of the gear rack.

[0017] In a possible design, a widened portion is provided between the rack portion and the center axis of the valve stem.

[0018] With the above design, the widened part increases the overall width of the valve stem, providing space for the opening of the hemispheres and avoiding interference between the two hemispheres after they are fully opened; the widened part increases the weight of the valve stem, so that the gravity of the valve stem and the gravity of the hemispheres offset each other to a certain extent, thereby being able to lift the hemisphere more effortlessly when the valve stem moves downward, and, when the valve stem moves upward, reducing the pressure transmitted to the valve stem due to the downward rotation of the hemisphere, reducing the opening and closing torque of the valve stem, and making the opening and closing of the valve easier and smoother.

[0019] In a possible design, the rotation center of the gear shaft is eccentrically arranged toward the lower half of the valve chamber.

[0020] The above design means that the hemisphere gradually breaks away from the contact with the valve seat when rotating upward, which helps to reduce the opening torque of the valve stem.

[0021] In a possible design, the valve stem outer sleeve is provided with an expansion joint, the bottom end of the expansion joint is welded to the valve stem, and the top end of the expansion joint is provided with a clamping plate, which is fixedly connected to the expansion joint and fixedly mounted on the box body.

[0022] With the above design, the expansion joint can effectively prevent the medium from leaking from the gap between the valve stem and the box body, can better absorb and buffer the vibration of the valve stem during the opening and closing process, and is suitable for the valve stem of the rack and pinion transmission method.

[0023] In one possible design, the valve seat includes a PEEK sealing ring, a pressure ring, and a welded alloy layer fixed on the valve body. The PEEK sealing ring is closer to the valve stem side relative to the welded alloy layer. The pressure ring presses the side end of the PEEK sealing ring against the valve body and is fixed to the valve body by bolts.

[0024] With the above design, the PEEK sealing ring has a compensatory sealing effect on the sealing of the cladding alloy layer, so that the valve seat can adapt to various harsh working conditions such as high temperature, high pressure, corrosion or containing solid particles, ensuring the stable operation of the valve seat in different environments and reducing the failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a cross-sectional view of a closed state of a specific embodiment of the present invention; Figure 2 It is a cross-sectional view of a specific embodiment of the present invention in an open state; Figure 3 is another cross-sectional view of the open state of a specific embodiment of the present invention; Figure 4 is a cross-sectional view of another embodiment of the present invention; Figure 5 For the present invention Figure 1 A partial enlarged view of the middle A; Among them, 1. hemisphere; 11. gear shaft; 2. valve body; 21. valve cavity; 22. inlet flow channel; 23. outlet flow channel; 24. limiting protrusion; 3. valve stem; 31. rack part; 32. widened part; 4. valve seat; 41. PEEK sealing ring; 42. pressure ring; 43. surfacing alloy layer; 5. box body; 6. expansion joint; 61. clamping plate. DETAILED DESCRIPTION

[0026] like Figure 1-Figure 3A self-cleaning hemispherical valve shown in the figure includes a hemispherical body 1, a valve body 2, a valve stem 3 and a valve seat 4. The valve body 2 has a valve cavity 21, and the two sides of the valve cavity 21 are respectively provided with an inlet flow channel 22 and an outlet flow channel 23. The hemispherical body 1 is horizontally installed in the valve cavity 21, that is, the rotation axis of the hemispherical body 1 is arranged horizontally and perpendicular to the valve stem 3. The valve cavity 21 is divided into an upper half of the valve cavity 21 and a lower half of the valve cavity 21 along the horizontal plane at its center. A box body 5 is installed on the horizontal side of the valve body 2, and the position of the box body 5 is not the traditional way of being set at the top of the valve body 2; the valve stem 3 is vertically inserted in the box body 5 and is connected to the hemispherical body 1 by gear transmission. When the valve is opened, the valve stem 3 moves downward along its vertical axis, and through the gear transmission with the hemispherical body 1, it drives the hemispherical body 1 to lift and rotate from the horizontal plane to the upper half of the valve cavity 21. When the valve is opened, the hemisphere 1 rotates upward to the upper half of the valve cavity 21, and the lower half of the valve cavity 21 is completely exposed in the fluid channel. There is no longer any obstruction from the valve stem 3 or the hemisphere 1 of the prior art. With the help of the pressure of the fluid, the lower half of the valve cavity 21 can achieve self-cleaning, effectively preventing the residue and accumulation of the medium. If the valve needs to be closed, the valve stem 3 moves upward, and drives the hemisphere 1 to descend from the upper half of the valve cavity 21 and rotate back to the horizontal plane through the gear transmission. Even if the medium remains in the lower half of the valve cavity 21, it is difficult for the hemisphere 1 to contact the residual medium in the lower half of the valve cavity 21 during the closing process, thereby avoiding the contact between the hemisphere 1 and the residual medium, and reducing the obstruction of the residue to the opening and closing of the hemisphere 1. In order to adapt to the rotation mode of the hemisphere 1, the operation mode of the valve is changed from the traditional angular stroke to the straight stroke, and the vertical rotation opening and closing of the hemisphere 1 is realized through the cooperation of the rack and gear on the valve stem 3.

[0027] There are two hemispheres 1, which are arranged on both sides of the valve stem 3. The two hemispheres 1 are arranged in mirror symmetry and are respectively sealed with the valve seats 4 at the inlet flow channel 22 and the outlet flow channel 23, so that they can be switched on and off with the corresponding valve seats 4; the valve stem 3 is respectively connected to the two hemispheres 1 through gear transmission. When the valve stem 3 moves, the two hemispheres 1 move synchronously. The two hemispheres 1 are sealed at the inlet flow channel 22 and the outlet flow channel 23, and the sealing performance is better. At the same time, the two hemispheres 1 arranged in mirror symmetry make the force on the valve more balanced during the opening and closing process.

[0028] The valve stem 3 has a rack portion 31 at the radially opposite sides, that is, it has two rack portions 31 at opposite sides, and the rack portions 31 are arranged in opposite directions; a gear shaft 11 is fixed at the rotation center position of one end of each hemisphere 1, and the gear of the gear shaft 11 is meshed with the rack of the rack portion 31. When the valve needs to be opened, the rack portion 31 on the valve stem 3 moves downward along the axial direction of the valve stem 3, and the two rack portions 31 on the valve stem 3 are respectively meshed with the gear shafts 11 of the two hemispheres 1, so that the two gear shafts 11 rotate at the same time but in opposite directions. The rotation of the two gear shafts 11 drives the two hemispheres 1 to rotate from the horizontal plane to the upper half of the valve cavity 21, and the two hemispheres 1 rotate 90 degrees in the vertical direction and finally reach the upper half of the valve cavity 21. When the two hemispheres 1 rotate to the upper half of the valve cavity 21, the channel between the inlet flow channel 22 and the outlet flow channel 23 is completely opened, and the medium can flow freely. When the valve needs to be closed, the rack portion 31 on the valve stem 3 moves upward along its axial direction, and the two rack portions 31 on the valve stem 3 respectively mesh with the gear shafts 11 of the two hemispheres 1, so that the two gear shafts 11 rotate in the opposite direction, and the two hemispheres 1 rotate 90 degrees in the vertical direction, and finally return to the horizontal position of the valve cavity 21. When the two hemispheres 1 return to the horizontal position, the two hemispheres 1 and the corresponding valve seats 4 fit tightly again to form a double seal to prevent the flow of the medium. In addition, by adjusting the transmission ratio between the rack portion 31 and the gear shaft 11, it is ensured that the gear shaft 11 has a 90-degree rotation range within the moving range of the rack portion 31.

[0029] The bottom of the lower half of the valve cavity 21 is a concave curved surface. When the valve is opened, the fluid enters the valve cavity 21 from the inlet flow channel 22, and can more effectively take away the residual medium in the valve cavity 21 through the concave curved surface. The concave curved surface reduces the dead angle area in the lower half of the valve cavity 21, making it easier for the fluid to cover the entire bottom of the valve cavity 21, reducing the accumulation of the medium in the dead angle, helping to keep the valve cavity 21 clean and extending the service life of the valve. At the same time, it is conducive to optimizing the flow path of the fluid in the valve cavity 21, reducing the impact of the fluid on the wall of the valve cavity 21, and reducing the energy loss during the fluid flow process.

[0030] like Figure 5 As shown, a limiting protrusion 24 is provided at the bottom of the lower half of the valve cavity 21, and the limiting protrusion 24 is limited against the hemispherical body 1 in the closed position, so that the hemispherical body 1 is supported by the limiting protrusion 24 in the closed position, and the supporting pressure is shared for the meshing of the gear shaft 11 and the rack part 31, which is particularly suitable for the state where the hemispherical valve is closed for a long time. Of course, the limiting protrusion 24 can also limit the excessive rotation of the hemispherical body 1, and is used to determine the closed position of the hemispherical body 1. In order to ensure the structural strength of the limiting protrusion 24, a reinforcing rib is used for support.

[0031] There is a widened portion 32 between the rack portion 31 and the center axis of the valve stem 3. During the valve opening process, the hemisphere 1 rotates upward to the upper half of the valve cavity 21, and the widened portion 32 ensures that the hemisphere 1 has enough space to rotate, avoiding collision and interference between the hemispheres 1, and ensuring the smooth opening and closing of the valve. The widened portion 32 increases the overall width of the valve stem 3, provides space for the opening of the hemisphere 1, ensures that the hemisphere 1 does not hinder the flow of the flow channel when it is fully opened, and avoids interference between the two hemispheres 1 after they are fully opened. The widened portion 32 also increases the overall weight of the valve stem 3, which can offset the gravity of the hemisphere 1, that is, the gravity of the valve stem 3 and the gravity of the hemisphere 1 offset each other to a certain extent. When the valve stem 3 moves downward, the hemisphere 1 can be lifted more effortlessly, reducing the required driving force. When the valve stem 3 moves upward, the gravity of the widened portion 32 can reduce the pressure transmitted to the valve stem 3 due to the downward rotation of the hemisphere 1, thereby alleviating the opening and closing torque of the valve stem 3 and making the opening and closing of the valve easier and smoother.

[0032] The rotation center of the gear shaft 11 is eccentrically arranged toward the lower half of the valve cavity 21 , so that the rotation center of the gear shaft 11 is located in the lower half of the valve cavity 21 . This means that the hemisphere 1 gradually breaks away from contact with the valve seat 4 when rotating upward, which helps to reduce the opening torque of the valve stem 3 .

[0033] The valve stem 3 is covered with a telescopic joint 6, the bottom end of the telescopic joint 6 is welded to the valve stem 3, and the top end of the telescopic joint 6 is provided with a clamping plate 61, which is fixedly connected to the telescopic joint 6 and fixedly mounted on the box body 5. The elastic telescopic structure of the telescopic joint 6 can better absorb and buffer the vibration of the valve stem 3 during the opening and closing process, and is suitable for the valve stem 3 with a rack and pinion transmission.

[0034] like Figure 5 As shown, the valve seat 4 includes a PEEK sealing ring 41, a pressure ring 42, and a cladding alloy layer 43 fixed on the valve body 2. The PEEK sealing ring 41 is closer to the valve stem 3 than the cladding alloy layer 43. The pressure ring 42 presses the side end of the PEEK sealing ring 41 against the valve body 2 and is fixedly connected to the valve body 2 by bolts. The cladding alloy layer 43 forms a seal with the hemispherical body 1, and the PEEK sealing ring 41 plays a compensating sealing effect.

[0035] Another embodiment: Figure 4 As shown, different from the above-mentioned embodiment, the hemisphere 1 has one and is arranged on one side close to the inlet flow channel 22, the valve stem 3 has only one rack portion 31, and a gear shaft 11 is fixed at the rotation center position of one end of the hemisphere 1, and the gear shaft 11 and the rack portion 31 are meshed. Using only one hemisphere 1 simplifies the internal structure of the valve, reduces the number of parts, and makes the overall design more compact and simple. In addition, due to the reduction of the opening and closing torque, the valve has a faster opening and closing speed and a shorter response time.

Claims

1. A self-cleaning hemispherical valve, comprising a hemispherical body (1), a valve body (2), a valve stem (3) and a valve seat (4), wherein the valve body (2) has a valve cavity (21), and the valve cavity (21) has an inlet flow channel (22) and an outlet flow channel (23) on both sides thereof, characterized in that: The hemisphere (1) is horizontally installed in the valve cavity (21), and the valve cavity (21) is divided into an upper half of the valve cavity (21) and a lower half of the valve cavity (21) along a horizontal plane at its center. A box (5) is installed on the horizontal side of the valve body (2). The valve stem (3) is vertically inserted into the box (5) and is connected to the hemisphere (1) through a gear transmission. The valve stem (3) moves along its axial direction and drives the hemisphere (1) to rotate from the horizontal plane to the upper half of the valve cavity (21) through the gear transmission to open the valve.

2. The self-cleaning hemispherical valve according to claim 1, characterized in that: The hemispherical bodies (1) have two and are disposed on both sides of the valve stem (3); the two hemispherical bodies (1) are arranged in a mirror-symmetrical manner and respectively form an opening and closing switch with the inlet flow channel (22) and the outlet flow channel (23); the valve stem (3) is respectively connected to the two hemispherical bodies (1) through gear transmission.

3. The self-cleaning hemispherical valve according to claim 2, characterized in that: The valve stem (3) has rack portions (31) at radially opposite sides thereof, and a gear shaft (11) is fixed at the rotation center position of one end of each hemispherical body (1), and the gear shaft (11) and the rack portion (31) are meshed.

4. The self-cleaning hemispherical valve according to claim 1, characterized in that: The hemispherical body (1) has one side arranged close to the inlet flow channel (22), the valve stem (3) has a rack portion (31), a gear shaft (11) is fixed at the rotation center position of one end of the hemispherical body (1), and the gear shaft (11) and the rack portion (31) are meshed.

5. The self-cleaning hemispherical valve according to claim 3 or 4, characterized in that: The bottom of the lower half of the valve cavity (21) is in the shape of a concave curved surface.

6. The self-cleaning hemispherical valve according to claim 3 or 4, characterized in that: A limiting protrusion (24) is provided at the bottom of the lower half of the valve cavity (21), and the limiting protrusion (24) abuts against the hemispherical body (1) in the closed position for limiting position.

7. The self-cleaning hemispherical valve according to claim 3 or 4, characterized in that: A widened portion (32) is provided between the rack portion (31) and the center axis of the valve stem (3).

8. The self-cleaning hemispherical valve according to claim 3 or 4, characterized in that: The rotation center of the gear shaft (11) is eccentrically arranged toward the lower half of the valve chamber (21).

9. The self-cleaning hemispherical valve according to claim 3 or 4, characterized in that: The valve stem (3) is covered with a telescopic joint (6), the bottom end of the telescopic joint (6) is welded to the valve stem (3), the top end of the telescopic joint (6) is provided with a clamping plate (61), and the clamping plate (61) is fixedly connected to the telescopic joint (6) and fixedly mounted on the box body (5).

10. The self-cleaning hemispherical valve according to claim 3 or 4, characterized in that: The valve seat (4) comprises a PEEK sealing ring (41), a pressure ring (42) and a cladding alloy layer (43) fixed on the valve body (2); the PEEK sealing ring (41) is closer to one side of the valve stem (3) than the cladding alloy layer (43); the pressure ring (42) presses the side end of the PEEK sealing ring (41) against the valve body (2) and is fixedly connected to the valve body (2) by bolts.

Images