Cantilevered track butterfly valve

Abstract

The application discloses a cantilever type track butterfly valve and belongs to the technical field of industrial valves. The valve body, the valve shaft, the rotary arm butterfly plate and the guide rail valve cover are provided with a guide assembly between the valve shaft and the guide rail valve cover. The assembly comprises a guide shaft and a rolling shaft sleeve. The guide rail valve cover is provided with a guide rail in sliding cooperation with the rolling shaft sleeve. The guide rail is a closed track groove, which can convert the linear motion of the valve shaft into rotary motion. The rotary arm butterfly plate is provided with a sliding pin at the upper end. The lower end of the valve shaft is provided with a curved rail in sliding cooperation with the sliding pin. The rotary arm butterfly plate is supported in the valve body through a lower shaft. The valve body is provided with a valve seat sealing assembly with a scraper. The scraper can automatically clean the sealing surface during opening and closing. The valve shaft and the guide rail valve cover are provided with a graphite packing seal. The application solves the problems of poor stability, easy wear of the sealing surface, easy leakage of the packing and difficult selection of the high-frequency opening and closing actuator of the existing track butterfly valve. The application has the advantages of rapid opening and closing, reliable sealing, anti-impurity and long service life.

Description

Technical Field

[0001] This invention relates to the field of industrial valve technology, and specifically to a cantilevered track butterfly valve. Background Technology

[0002] Rail-mounted butterfly valves, a new type of valve combining the advantages of compact structure and rapid opening and closing of butterfly valves with the reliable sealing of gate valves, are widely used in industrial fields due to their frictionless opening and closing and good sealing performance. While existing rail-mounted butterfly valves have solved the problems of high opening and closing torque and easy wear of sealing surfaces in traditional butterfly valves to some extent, they still have the following shortcomings in practical applications, especially under complex working conditions involving high frequency, high pressure, and media containing impurities: 1. Insufficient stability of valve stem connection structure: In the existing technology, the connection structure between valve stem and butterfly plate is mostly a simple pin connection. Under high pressure conditions, the valve stem of the cantilever structure is prone to radial displacement, resulting in uneven contact pressure between the butterfly plate sealing surface and the valve seat sealing surface, which seriously affects the sealing reliability and service life of the valve.

[0003] 2. Limited stiffness of the cantilever support structure: The support structure of the cantilever valve stem is poorly designed, resulting in insufficient overall stiffness. During rapid valve opening and closing, especially at the moment of opening and closing, the fluid impact force on the butterfly plate is easily transmitted to the valve stem, causing valve stem vibration and impact. This not only generates noise but also accelerates fatigue damage to various transmission components, reducing the overall lifespan of the valve.

[0004] 3. Packing seal wear leads to external leakage: Under high-frequency opening and closing conditions, the combined motion of the valve stem's "lifting + rotation" generates continuous friction and compression on the packing inside the stuffing box, causing the packing to wear faster, the sealing performance to decline, and the medium to easily leak out, resulting in energy waste and environmental pollution, as well as increased maintenance costs.

[0005] 4. Lack of protection and compensation mechanisms for sealing surfaces: In media containing particles, prone to crystallization, or prone to scaling (such as sewage, mud, and slurry), impurities easily deposit or adhere to the sealing surfaces of the butterfly plate or valve seat. During valve opening and closing, these impurities can scratch the delicate sealing surfaces, leading to internal leakage. Furthermore, existing valves lack effective automatic wear compensation mechanisms; once the sealing surfaces are worn, the sealing performance drops sharply.

[0006] 5. Difficulty in selecting actuators under high-frequency operating conditions: In order to achieve the complex movement trajectory of the valve stem, traditional track butterfly valves often require specially made actuators with complex structures and large output torque. This is not only costly, but also difficult to select in industrial control scenarios that require high frequency and fast response, making it difficult to meet the needs of automation control. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a cantilevered rail butterfly valve to solve the technical problems of poor stability, easy wear of sealing surface, easy leakage of packing and difficulty in selecting actuator of existing rail butterfly valves under high pressure conditions.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a cantilevered rail butterfly valve, comprising a valve body, a valve shaft rotatably mounted within the valve body, and a rotating butterfly plate driven by the valve shaft, characterized in that it further comprises a guide assembly, the guide assembly being disposed between the valve shaft and a guide rail valve cover, for guiding the valve shaft to perform a combined lifting and rotating motion; the guide assembly comprising a guide shaft passing through the valve shaft and a rolling sleeve sleeved at the end of the guide shaft; the guide rail valve cover is provided with a guide rail that slides with the rolling sleeve, the guide rail being a closed track groove, for converting the linear motion of the valve shaft into rotational motion; The upper end of the rotary butterfly plate is provided with a guide hole, and a sliding pin is provided on the inner side wall of the guide hole. The lower end of the valve shaft is provided with a curved track, which is inserted into the guide hole and slides in contact with the sliding pin. The lower end of the rotary butterfly plate is rotatably supported in the valve body by a lower shaft and a lower shaft sleeve, so as to realize the movement of the rotary butterfly plate and the rotation around the axis when the valve shaft is raised, lowered and rotated.

[0009] Preferably, the lower part of the guide rail is a vertical straight track groove, and the upper part is a spiral track groove; the guide rail and rolling bushing are provided in two parts and are symmetrically distributed along the axial direction of the valve shaft.

[0010] Preferably, the upper end of the curved track is arc-shaped, the lower end is straight, and its cross-section is non-circular; the cross-sectional shape of the curved track matches that of the guide hole.

[0011] Preferably, the valve body is provided with a valve seat sealing assembly that seals with the rotary butterfly plate. The valve seat sealing assembly includes a valve body sealing pressure plate, a valve body sealing ring, a scraper, and a scraper pressure plate. The scraper is detachably mounted on the rotary butterfly plate via the scraper pressure plate. The valve body sealing ring is detachably mounted on the inlet end of the valve body via the valve body sealing pressure plate. A spring is provided between the valve body sealing ring and the valve body sealing pressure plate. The outer edge of the scraper protrudes from the scraper pressure plate and the rotary butterfly plate, and elastically contacts the sealing surface of the valve body sealing ring during valve opening and closing. The contact surface is funnel-shaped, which can scrape off impurities attached to the sealing surface of the valve body sealing ring.

[0012] Preferably, the lower end of the valve body is detachably fitted with a bottom cover; it also includes a lower shaft mounting assembly, which includes a lower shaft locking ring, a lower shaft bearing, a lower shaft sleeve gasket, and a metal spiral wound gasket; the upper end of the lower shaft is hinged to the rotary arm butterfly plate via a ball joint structure; the lower shaft locking ring is fitted and fixed to the bottom outer peripheral wall of the lower shaft, and the lower shaft bearing, lower shaft sleeve gasket, and lower shaft sleeve are sequentially fitted on the lower shaft locking ring from bottom to top; the metal spiral wound gasket is disposed between the bottom cover and the valve body.

[0013] Preferably, a packing seal structure is provided between the valve shaft and the guide rail valve cover. The packing seal structure includes a graphite packing assembly disposed inside the guide rail valve cover and a packing press frame for pressing the graphite packing assembly. The graphite packing assembly includes three or more graphite rings. A sealing chamber structure is formed on the lower inner side wall of the guide rail valve cover. The graphite rings are vertically stacked in the sealing chamber structure and fitted onto the outer wall of the valve shaft. A packing ring is press-fitted onto the uppermost graphite ring. A pressure frame mounting groove is symmetrically formed on the side wall of the guide rail valve cover above the sealing chamber structure. The two ends of the packing frame are set in the pressure frame mounting groove, and the middle part of the packing frame is fitted onto the valve shaft. The packing frame can seal and press the packing ring tightly.

[0014] Preferably, an injection hole is provided on the side wall of the guide rail valve cover, and a one-way valve plug is installed on the injection hole.

[0015] Preferably, the upper end of the valve shaft is connected to the actuator via a connecting sleeve; a bearing is provided inside the connecting sleeve, and the upper end of the valve shaft passes through the bearing, so that the actuator can drive the valve shaft to move up and down synchronously while rotating through linear motion.

[0016] Preferably, an upper bushing is provided between the upper part of the valve body and the valve shaft; the valve body is installed and fixed with the guide rail valve cover and the guide rail valve cover with the packing pressure frame by bolts and nuts.

[0017] Preferably, a buffer mechanism is provided above the vertical straight track groove of the guide rail. The buffer mechanism includes a buffer block, a buffer spring, and a buffer top screw. Buffer chambers are symmetrically opened in the side wall of the guide rail valve cover above the vertical straight track groove. Buffer top screws, buffer springs, and buffer blocks are installed sequentially from top to bottom in the buffer chambers. The lower end of the buffer block extends out of the buffer chamber and is inserted into the guide rail.

[0018] Preferably, it also includes an anti-blowout structure, which includes an oblique outer conical annular platform located at the lower end of the valve shaft and an oblique inner conical annular groove located at the lower end of the guide rail valve cover, wherein the outer wall of the oblique outer conical annular platform matches the inner wall of the oblique inner conical annular groove.

[0019] Compared with the prior art, the technical solution of the present invention has the following outstanding advantages: 1. Precise Guidance and Smooth Operation: This invention employs a dual-guide shaft structure, with a guide shaft running through the valve stem and a rolling sleeve fitted at the end of the guide shaft, slidingly engaging with the guide rail on the valve cover. This replaces traditional sliding friction with rolling friction, significantly reducing frictional resistance and component wear during valve stem movement. Simultaneously, the dual-guide shaft structure is symmetrically distributed along the valve stem axis, effectively improving the support stiffness of the cantilever valve stem, preventing radial displacement under high-pressure conditions, and ensuring uniform contact pressure between the rotary disc sealing surface and the valve body sealing ring, thereby guaranteeing the valve's opening and closing stability under high-pressure and high-frequency conditions.

[0020] 2. Self-cleaning and long-term compensation of the sealing surface: The valve seat sealing assembly adopts a unique scraper design. The scraper is detachably installed on the rotary disc via a scraper pressure plate. Its outer edge protrudes from the scraper pressure plate and the rotary disc, making elastic contact with the sealing surface of the valve body sealing ring during valve opening and closing. The contact surface is funnel-shaped, effectively scraping away particles, scale, and other impurities adhering to the sealing surface of the valve body sealing ring, preventing impurities from entering the sealing surface and causing scratches. At the same time, the valve body sealing ring is installed at the valve body inlet end via the valve body sealing pressure plate. With the help of a spring as an elastic compensation structure, it can automatically compensate for the wear of the sealing surface caused by long-term use, ensuring that the sealing specific pressure is always within a reasonable range and achieving long-term reliable sealing performance.

[0021] 3. Shock Elimination and Lifespan Extension: A buffer mechanism is installed above the vertical straight track groove of the guide rail. This mechanism is located inside the guide rail valve cover. When the valve shaft rises to the end of its stroke, the rolling bushing contacts the buffer mechanism, effectively absorbing the impact kinetic energy of the moving parts and avoiding rigid collisions. This design significantly reduces the vibration and noise generated during valve opening and closing, reduces fatigue damage to various transmission components, and extends the overall service life of the valve.

[0022] 4. Reliable sealing and prevention of external leakage: A multi-layer graphite packing combination sealing structure is adopted. A sealing chamber is set inside the guide rail valve cover, and multiple graphite rings are vertically stacked and fitted onto the outer wall of the valve shaft, and pressed together by packing pressure rings and packing pressure frames. This design effectively prevents the medium from leaking outwards along the valve shaft during the "lifting + rotating" compound motion of the valve shaft. With no solid friction and allowing for thermal expansion gaps, it significantly extends the service life of the packing seal and eliminates external media leakage.

[0023] 5. High versatility and suitability for high-frequency applications: The structure with an inlaid bearing in the connecting sleeve efficiently converts the linear motion of the linear actuator into the "lifting + rotating" composite motion required by the valve shaft, significantly reducing energy loss during transmission and the special requirements on the actuator. This design allows conventional, low-cost linear actuators to meet the requirements of high-frequency, rapid opening and closing conditions, eliminating the need for customized special actuators, reducing system integration costs and selection complexity, and effectively ensuring high-frequency performance.

[0024] 6. Smooth operation and strong resistance to impurities: Inheriting the advantages of the cantilevered rail transmission structure, combined with the scraper cleaning structure and the reliable connection design between the bottom shaft and the rotary disc, it can effectively prevent material accumulation and jamming in environments containing particulate or crystalline media, ensuring smooth opening and closing, and significantly improving the valve's adaptability in media containing particulates and prone to scaling.

[0025] 7. Wide range of operating conditions adaptability: This invention is applicable to high pressure, medium pressure and low pressure environments, and integrates multiple advantages such as eliminating jamming, low wear, self-cleaning and sealing compensation. It can be widely adapted to complex and harsh operating conditions such as high pressure, particle content, easy scaling, and alternating high and low temperatures, covering multiple industrial fields such as petrochemical, power, metallurgy, environmental protection, military, and nuclear power, with outstanding overall cost performance.

[0026] 8. Convenient maintenance and reliable structure: The bottom cover of the valve body is detachably installed, which facilitates the inspection and maintenance of the lower shaft mounting components; the scraper is detachably installed through the scraper pressure plate, which is convenient for replacement; the valve body and the guide rail valve cover, and the guide rail valve cover and the packing pressure frame are fixed with bolts and nuts, which is reliable and easy to disassemble and assemble, significantly improving the convenience of on-site maintenance. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural diagram of the cantilevered track butterfly valve described in this invention; Figure 2 This is a three-dimensional structural schematic diagram (from another angle) of the cantilevered track butterfly valve described in this invention. Figure 3 This is a front view of the cantilevered track butterfly valve described in this invention. Figure 4 for Figure 3 Sectional view along axis AA; Figure 5 This is a three-dimensional structural diagram of the valve shaft, rotary arm butterfly plate and valve seat sealing assembly assembled according to the present invention. Figure 6 This is a front view of the assembled valve shaft, rotary arm butterfly plate, and valve seat sealing assembly according to the present invention. Figure 7 for Figure 6BB-direction sectional view; Figure 8 This is a three-dimensional structural diagram of the valve shaft described in this invention; Figure 9 This is a three-dimensional structural diagram of the spiral arm butterfly plate described in this invention; Figure 10 This is a three-dimensional structural diagram (from another angle) of the spiral arm butterfly plate described in this invention. Figure 11 This is a three-dimensional structural diagram of the guide rail valve cover described in this invention.

[0028] In the diagram: 1. Valve body; 2. Bottom cover; 3. Lower shaft locking ring; 4. Lower shaft bearing; 5. Lower shaft sleeve gasket; 6. Metal spiral wound gasket; 7. Lower shaft; 8. Lower shaft sleeve; 9. Ball head structure; 10. Valve body sealing pressure plate; 11. Scraper; 12. Scraper pressure plate; 13. Rotary arm butterfly plate; 14. Sliding pin; 15. Valve shaft; 16. Valve body sealing ring; 17. Upper shaft sleeve; 18. Upper shaft sleeve gasket; 19. Graphite packing assembly; 2 0. Guide rail valve cover; 21. Packing ring; 22. Packing frame; 23. Guide shaft; 24. Rolling bushing; 25. Connecting sleeve; 26. Bearing; 27. Guide rail; 28. Guide hole; 29. ​​Curved rail; 30. Spring; 31. Injection hole; 32. One-way valve plug; 33. Buffer screw; 34. Buffer spring; 35. Buffer stop; 36. Angled outer conical surface annular platform; 37. Angled inner conical surface annular groove. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, it should be noted that unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," and "set up" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The following describes embodiments of the invention based on its overall structure.

[0031] like Figures 1 to 11 As shown, the present invention provides a cantilevered track butterfly valve, comprising a valve body 1, a valve shaft 15 rotatably mounted within the valve body 1, and a rotating butterfly plate 13 driven by the valve shaft 15. The valve body 1 serves as the basic support component of the entire valve, and has a fluid passage formed inside. A bottom cover 2 is detachably installed at the lower end of the valve body 1 to seal the bottom of the valve body and facilitate the installation and maintenance of internal components. A valve seat sealing assembly is provided at the inlet end of the valve body 1 to cooperate with the rotating butterfly plate 13 to achieve a seal.

[0032] The valve shaft 15 is rotatably and vertically mounted within the valve body 1 and is the core component for transmitting driving force. A guide assembly is provided between the valve shaft 15 and the guide rail valve cover 20 to guide the valve shaft 15 in a combined vertical and rotary motion. This guide assembly includes a guide shaft 23 that passes through the valve shaft 15 and a rolling sleeve 24 fitted onto the end of the guide shaft 23. The guide shaft 23 passes radially through the valve shaft 15, with both ends extending out of the sidewalls of the valve shaft 15. The guide rail valve cover 20 is provided with a guide rail 27 that slides with the rolling sleeve 24. This guide rail 27 is a closed track groove used to convert the linear motion of the valve shaft 15 into rotary motion. The lower part of the guide rail 27 is a vertical straight track groove, and the upper part is a spiral track groove. This design allows the valve shaft 15 to initially perform a pure linear motion during the initial upward movement, and then generate rotary motion when entering the spiral section. Two guide rails 27 and rolling bushings 24 are provided and symmetrically distributed along the axial direction of valve shaft 15 to form a double guide shaft structure, which effectively improves the support stiffness and motion accuracy of the cantilever valve stem.

[0033] The upper end of the rotary butterfly plate 13 has a guide hole 28, and a sliding pin 14 is provided on the inner wall of the guide hole 28. The lower end of the valve shaft 15 has a curved track 29, which is inserted into the guide hole 28 and slides in contact with the sliding pin 14. The upper end of the curved track 29 is arc-shaped, the lower end is straight, and its cross-section is non-circular. The cross-sectional shape of the curved track 29 matches that of the guide hole 28. The upper end of the lower shaft 7 is hinged to the rotary butterfly plate 13 through a ball joint structure 9. The rotary butterfly plate 13 can swing and rotate relative to the lower shaft 7 around the ball joint structure 9. The lower shaft 7 is rotatably supported in the valve body 1. Specifically, the lower shaft locking ring 3 is fixedly mounted on the bottom outer peripheral wall of the lower shaft 7. The lower shaft bearing 4, the lower shaft sleeve gasket 5, and the lower shaft sleeve 8 are sequentially mounted on the lower shaft locking ring 3 from bottom to top. The metal spiral wound gasket 6 is provided between the bottom cover 2 and the valve body 1 to ensure the reliability of the bottom seal.

[0034] The valve body 1 is equipped with a valve seat sealing assembly that seals with the rotary butterfly plate 13. This assembly includes a valve body sealing pressure plate 10, a valve body sealing ring 16, a scraper 11, and a scraper pressure plate 12. The scraper 11 is detachably mounted on the rotary butterfly plate 13 via the scraper pressure plate 12 (preferably bolted in this embodiment). The valve body sealing ring 16 is detachably mounted on the inlet end of the valve body 1 via the valve body sealing pressure plate 10 (preferably bolted in this embodiment). A spring 30 is provided between the valve body sealing ring 16 and the valve body sealing pressure plate 10. The outer edge of the scraper 11 protrudes from the scraper pressure plate 12 and the rotary butterfly plate 13, and elastically contacts the sealing surface of the valve body sealing ring 16 during valve opening and closing. The contact surface is funnel-shaped, effectively scraping away impurities adhering to the sealing surface of the valve body sealing ring 16 and preventing impurities from entering the sealing surface and causing scratches.

[0035] A packing seal structure is provided between the valve shaft 15 and the guide rail valve cover 20. This packing seal structure includes a graphite packing assembly 19 disposed inside the guide rail valve cover 20 and a packing pressure frame 22 that presses the graphite packing assembly 19. The graphite packing assembly 19 includes three or more graphite rings. A sealing chamber structure is formed on the lower inner side wall of the guide rail valve cover 20. The graphite rings are vertically stacked in the sealing chamber structure and fitted onto the outer wall of the valve shaft 15. A packing pressure ring 21 is pressed onto the uppermost graphite ring. A pressure frame mounting groove is symmetrically formed on the side wall of the guide rail valve cover 20 above the sealing chamber structure. The two ends of the packing pressure frame 22 are disposed in the pressure frame mounting groove, and the middle part of the packing pressure frame 22 is fitted onto the valve shaft 15. The packing pressure frame 22 and the packing pressure ring 21 are in conical contact. The packing pressure frame 22 can seal and press the packing pressure ring 21, thereby achieving a reliable shaft seal.

[0036] A glue injection hole 31 is provided on the side wall of the guide rail valve cover 20, and a one-way valve plug 32 is installed on the glue injection hole 31. The one-way valve plug 32 is assembled to the glue injection hole 31 by a threaded connection. This glue injection structure can realize online glue injection during valve operation. By replenishing the stuffing box with sealant, the sealing performance of the packing is maintained, thereby significantly extending the service life of the packing.

[0037] The upper end of the valve shaft 15 is connected to the actuator via a connecting sleeve 25. A bearing 26 is installed inside the connecting sleeve 25, and the upper end of the valve shaft 15 passes through the bearing 26. This connection method allows the actuator to drive the valve shaft 15 to move synchronously up and down via linear motion, while the valve shaft 15 can rotate freely relative to the connecting sleeve 25 under the action of the guide rail 27. An upper bushing 17 is provided between the upper part of the valve body 1 and the valve shaft 15 for support and guidance. The valve body 1 is fixed to the guide rail valve cover 20, and the guide rail valve cover 20 is fixed to the packing pressure frame 22 using bolts and nuts, resulting in a reliable structure that is easy to assemble and disassemble.

[0038] To eliminate the rigid impact at the end of the valve opening stroke, a buffer mechanism is provided above the vertical straight track groove of the guide rail 27. Buffer chambers are symmetrically formed inside the side wall of the guide rail valve cover 20 above the vertical straight track groove. Inside each buffer chamber, from top to bottom, a buffer screw 33, a buffer spring 34, and a buffer stop 35 are installed sequentially. The lower end of the buffer stop 35 extends out of the buffer chamber and inserts into the guide rail 27, with a guide slope on its lower end face matching the shape of the upper side wall of that part of the guide rail 27. When the valve shaft 15 rises to near the end of its stroke, the rolling sleeve 24 on the guide shaft 23 approaches the uppermost end of the vertical straight track groove. At this time, the rolling sleeve 24 first contacts the guide slope of the buffer stop 35, pushing the buffer stop 35 upward to compress the buffer spring 34. During this process, the compression reaction force of the buffer spring 34 absorbs the inertial kinetic energy of the moving parts, achieving smooth buffering. By adjusting the screw depth of the buffer screw 33, the preload of the buffer spring 34 can be changed, thereby adjusting the buffering effect.

[0039] The present invention also includes an anti-blowout structure, which includes an angled outer conical annular platform 36 located at the lower end of the valve shaft 15 and an angled inner conical annular groove 37 located at the lower end of the guide rail valve cover 20. The outer wall of the angled outer conical annular platform 36 matches the inner wall of the angled inner conical annular groove 37. The cone angle of the angled outer conical annular platform 36 and the angled inner conical annular groove 37 is preferably 45°. The anti-blowout structure prevents the medium pressure from axially pushing the valve shaft 15 out of the valve through structural limiting. It is a mandatory safety structure for high-pressure / safe conditions. When the valve shaft 15 performs a "rising + rotating" compound motion, when it moves to the highest point along the "S" spiral track by the guide shaft 23, the angled outer conical annular platform 36 on the valve shaft 15 and the angled inner conical annular groove 37 at the lower end of the guide rail valve cover 20 are tightly engaged, which plays the role of preventing blowout and providing a line seal.

[0040] The working process and principle of the cantilevered track butterfly valve of the present invention will be described in detail below.

[0041] When the valve is closed, the valve shaft 15 is at the lower limit position, and the guide shaft 23 and rolling sleeve 24 are located at the bottom of the vertical straight track groove at the lower part of the guide rail 27. At this time, the curved track 29 at the lower end of the valve shaft 15 presses the rotary butterfly plate 13 onto the valve body sealing ring 16 through the sliding pin 14. The sealing surface of the rotary butterfly plate 13 is tightly fitted with the valve body sealing ring 16, and the valve is in a reliable closed state, preventing the medium from passing through.

[0042] When the valve needs to be opened, the actuator (preferably a linear actuator) pushes the connecting sleeve 25 upward, and the connecting sleeve 25 drives the valve shaft 15 to rise synchronously. In the initial opening stage, since the rolling sleeve 24 on the guide shaft 23 is still located in the vertical straight track groove at the lower part of the guide rail 27, the rolling sleeve 24 moves linearly upward along the vertical straight track groove, so the valve shaft 15 only moves vertically upward. At this time, the curved track 29 at the lower end of the valve shaft 15 rises accordingly. Since the lower part of the curved track 29 is straight, this linear upward movement drives the rotary arm butterfly plate 13 to swing around the ball head structure 9 at the upper end of the lower shaft 7 through the sliding pin 14, so that the rotary arm butterfly plate 13 smoothly disengages from the valve body sealing ring 16. At this time, a gap is generated between the rotary arm butterfly plate 13 and the valve body sealing ring 16, thereby avoiding frictional wear on the sealing surface during subsequent rotation.

[0043] As the valve shaft 15 continues to rise, when the rolling sleeve 24 on the guide shaft 23 rises to the top of the vertical linear track groove, the rolling sleeve 24 contacts the buffer mechanism located inside the guide rail valve cover 20, pushing the buffer mechanism to compress the buffer spring 34. During this process, the compression reaction force of the buffer spring 34 absorbs the inertial kinetic energy of the moving parts, achieving smooth buffering and avoiding rigid impact. Then, the rolling sleeve 24 enters the spiral track groove on the upper part of the guide rail 27 and begins to move along the spiral trajectory under the guidance of the spiral track groove, thereby driving the valve shaft 15 to generate a rotational motion around its own axis while continuing to rise. The rotational motion of the valve shaft 15 is transmitted to the sliding pin 14 through the curved track 29 at its lower end. Since the cross-section of the curved track 29 is a non-circular cross-section, this rotational motion drives the sliding pin 14 and the rotary arm butterfly plate 13 to rotate around the axis of the lower shaft 7, so that the fluid passage is gradually opened. When the valve shaft 15 stops rising, the rotary arm butterfly plate 13 is fully opened to the maximum opening position, and the valve is in the fully open state.

[0044] When the valve needs to be closed, the actuator moves in the reverse direction, pulling the connecting sleeve 25 downwards, causing the valve shaft 15 to descend synchronously and rotate in the reverse direction. First, the rolling sleeve 24 enters the vertical straight track groove from the spiral track groove on the upper part of the guide rail 27. During this process, the valve shaft 15 first rotates in the reverse direction and descends, driving the rotary disc 13 to rotate in the reverse direction, gradually closing the fluid passage. After the rolling sleeve 24 is fully inserted into the vertical straight track groove, the valve shaft 15 only performs a linear descent. At this time, the curved track 29 at the lower end of the valve shaft 15 drives the sliding pin 14 and the rotary disc 13 to swing relative to the lower shaft 7, smoothly moving towards the valve body sealing ring 16, so that the sealing surface of the rotary disc 13 gradually approaches and finally presses against the valve body sealing ring 16, achieving a reliable seal. Meanwhile, as the rotary disc 13 moves, the scraper 11 mounted on the rotary disc 13 moves relative to the sealing surface of the valve body sealing ring 16. The outer edge of the scraper 11 thoroughly removes any particles, scale, or other impurities that may be attached to the sealing surface of the valve body sealing ring 16, keeping the sealing surface clean. When the valve shaft 15 descends to the lower limit, the rolling sleeve 24 is located at the bottom of the vertical linear track groove, and the valve returns to the closed state.

[0045] Throughout the opening and closing process, the scraper 11 maintains elastic contact with the valve body sealing ring 16, automatically cleaning the sealing surface with each opening and closing. Under the pressure of the packing frame 22, the graphite packing assembly 19 is always tightly fitted with the valve shaft 15, effectively preventing the medium from leaking outward along the valve shaft 15. When the valve body sealing ring 16 wears due to long-term use, the spring 30 on the back of the valve seat sealing assembly acts as an elastic compensation structure, automatically releasing the preload and pushing the valve body sealing ring 16 towards the rotary arm butterfly plate 13, automatically compensating for the wear and ensuring that the sealing pressure is always maintained within a reasonable range.

[0046] Through the above working process and principle, the present invention can achieve smooth opening and closing of valves without disassembling them, and effectively extend the service life of valves under complex working conditions by utilizing the self-cleaning function of the scraper, the automatic compensation function of the elastic compensation mechanism, and the impact absorption function of the buffer mechanism.

[0047] Product test data are shown in Table 1.

[0048] Table 1 - Test data of cantilevered track butterfly valve under extreme conditions.

[0049]

[0050] Experimental description: 1. Test medium: Inert gas (nitrogen) is used for high temperature tests, and clean water is used for low temperature and high pressure tests.

[0051] 2. Test equipment: High temperature test furnace (accuracy ±5℃), low temperature test chamber (accuracy ±1℃), high frequency opening and closing platform.

[0052] 3. Test environment: Standard atmospheric environment (temperature 23±2℃, humidity 50±5%RH).

[0053] 4. The cantilevered rail butterfly valve (DN150) conforms to API 609-2021 and GB / T 12238-2022; all tests meet the requirements of API 609-2021 and GB / T 12238-2022 standards, and the test data are true and valid.

[0054] 5. Tests have determined that the cantilevered rail butterfly valve can withstand a maximum high temperature of 1350℃ and a maximum low temperature of -196℃. It operates stably under high-frequency conditions, and all its performance meets the design and standard requirements.

[0055] The core conclusion of the test is that the extreme high temperature, extreme low temperature and high frequency tests that the valve can withstand have been verified by the test.

[0056] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A cantilevered track butterfly valve, comprising a valve body (1), a valve shaft (15) rotatably mounted within the valve body (1), and a rotating butterfly plate (13) driven by the valve shaft (15), characterized in that, It also includes a guide assembly, which is disposed between the valve shaft (15) and the guide rail valve cover (20) to guide the valve shaft (15) to perform a combined motion of lifting and rotating; the guide assembly includes a guide shaft (23) that passes through the valve shaft (15) and a rolling bushing (24) sleeved on the end of the guide shaft (23); the guide rail valve cover (20) is provided with a guide rail (27) that slides with the rolling bushing (24), the guide rail (27) is a closed track groove, which is used to convert the linear motion of the valve shaft (15) into rotational motion; The upper end of the rotary butterfly plate (13) is provided with a guide hole (28), and a sliding pin (14) is provided on the inner side wall of the guide hole (28). The lower end of the valve shaft (15) is provided with a curved track (29), which is inserted into the guide hole (28) and slides in contact with the sliding pin (14). The lower end of the rotary butterfly plate (13) is hinged to a lower shaft (5), which is rotatably supported in the valve body (1) to realize the movement of the rotary butterfly plate (13) and the rotation around the axis when the valve shaft (15) is raised, lowered and rotated.

2. The cantilevered track butterfly valve according to claim 1, characterized in that, The lower part of the guide rail (27) is a vertical straight track groove, and the upper part is a spiral track groove; the guide rail (27) and the rolling bushing (24) are set in two and are symmetrically distributed along the axial direction of the valve shaft (15).

3. The cantilevered track butterfly valve according to claim 1, characterized in that, The upper end of the curved track (29) is arc-shaped, the lower end is straight, and its cross-section is non-circular; the cross-sectional shape of the curved track (29) matches that of the guide hole (28).

4. The cantilevered track butterfly valve according to claim 1, characterized in that, The valve body (1) is provided with a valve seat sealing assembly that seals with the rotary butterfly plate (13). The valve seat sealing assembly includes a valve body sealing pressure plate (10), a valve body sealing ring (16), a scraper (11), and a scraper pressure plate (12). The scraper (11) is detachably mounted on the rotary butterfly plate (13) via the scraper pressure plate (12). The valve body sealing ring (16) is detachably mounted at the feed inlet end of the valve body (1) via the valve body sealing pressure plate (10). A spring (30) is provided between the valve body sealing ring (16) and the valve body sealing pressure plate (10). The outer edge of the scraper (11) protrudes from the scraper pressure plate (12) and the rotary butterfly plate (13), and elastically contacts the sealing surface of the valve body sealing ring (16) during the opening and closing of the valve. The contact surface is funnel-shaped, which can scrape off impurities attached to the sealing surface of the valve body sealing ring (16).

5. The cantilevered track butterfly valve according to claim 1, characterized in that, The lower end of the valve body (1) is detachably fitted with a bottom cover (2); it also includes a lower shaft mounting assembly, which includes a lower shaft locking ring (3), a lower shaft bearing (4), a lower shaft sleeve gasket (5), and a metal spiral wound gasket (6); the upper end of the lower shaft (7) is hinged to the rotary arm butterfly plate (13) by a ball head structure (9); the lower shaft locking ring (3) is fitted and fixed on the bottom outer peripheral wall of the lower shaft (7), and the lower shaft bearing (4), the lower shaft sleeve gasket (5), and the lower shaft sleeve (7) are fitted on the lower shaft locking ring (3) from bottom to top; the metal spiral wound gasket (6) is disposed between the bottom cover (2) and the valve body (1).

6. The cantilevered track butterfly valve according to claim 1, characterized in that, A packing seal structure is provided between the valve shaft (15) and the guide rail valve cover (20). The packing seal structure includes a graphite packing assembly (19) disposed inside the guide rail valve cover (20) and a packing pressure frame (22) that presses the graphite packing assembly (19). The graphite packing assembly (19) includes three or more graphite rings. A sealing chamber structure is opened on the lower inner side wall of the guide rail valve cover (20). The graphite rings are vertically stacked in the sealing chamber structure and fitted on the outer wall of the valve shaft (15). A packing ring (21) is press-fitted onto the uppermost graphite ring. A pressure frame mounting groove is symmetrically opened on the side wall of the guide rail valve cover (20) above the sealing chamber structure. The two ends of the packing pressure frame (22) are set in the pressure frame mounting groove and the middle part of the packing pressure frame (22) is fitted on the valve shaft (15). The packing pressure frame (22) can seal and press the packing ring (21).

7. The cantilevered track butterfly valve according to claim 6, characterized in that, An injection hole (31) is made on the side wall of the guide rail valve cover (20), and a one-way valve plug (32) is installed on the injection hole (31).

8. The cantilevered track butterfly valve according to claim 1, characterized in that, The upper end of the valve shaft (15) is connected to the actuator via a connecting sleeve (25); a bearing (26) is provided inside the connecting sleeve (25), and the upper end of the valve shaft (15) passes through the bearing (26) so that the actuator can drive the valve shaft (15) to move up and down synchronously while rotating through linear motion.

9. The cantilevered track butterfly valve according to claim 2, characterized in that, A buffer mechanism is provided above the vertical straight track groove of the guide rail (27). The buffer mechanism includes a buffer stop (35), a buffer spring (34), and a buffer top screw (33). Buffer chambers are symmetrically opened in the side wall of the guide rail valve cover (20) above the vertical straight track groove. Buffer top screws (33), buffer springs (34), and buffer stops (35) are installed sequentially from top to bottom in the buffer chambers. The lower end of the buffer stop (35) extends out of the buffer chamber and is inserted into the guide rail (27).

10. The cantilevered track butterfly valve according to claim 1, characterized in that, It also includes an anti-blowout structure, which includes an oblique outer conical annular platform (36) located at the lower end of the valve shaft (15) and an oblique inner conical annular groove (37) located at the lower end of the guide rail valve cover (20). The outer wall of the oblique outer conical annular platform (36) matches the inner wall of the oblique inner conical annular groove (37).

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