Reciprocating lift hard seal stopcock valve

Abstract

The utility model discloses a reciprocating lifting type hard sealing plug valve, including valve body, plug body, valve rod, operating device and reciprocating lifting device. The reciprocating lifting device is by drive ring, guide ring and drive shaft constitute, wherein the transverse hole groove of guide ring has the slope structure of special design. When working, operating device drives drive ring rotation, drives drive shaft synchronous rotation, and drive shaft end portion moves along the slope structure simultaneously, thereby forced drive shaft and the valve rod transmission connection with it rotate simultaneously and make axial lift movement. The utility model has realized the continuous action of plug body "lift - rotate - drop", and plug body and valve seat sealing pair can still keep the adhesion when the valve is in the full open or full close position, effectively avoided the solid particle in medium and adhered sealing surface.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, and in particular to a reciprocating lifting hard-seal plug valve. Background Technology

[0002] Like ball valves and butterfly valves, plug valves are partial-turn shut-off valves. The valve core only needs to rotate 90 degrees to complete the opening and closing action, offering advantages such as low flow resistance and convenient operation. Plug valves can be classified into three types based on their sealing structure: soft-seal, oil-seal, and hard-seal. Hard-seal plug valves can withstand high temperatures and pressures and have a wider range of applications. However, because the valve body and plug sealing surface of hard-seal plug valves are made of metal, the friction during operation is very high, making operation difficult. Therefore, both domestically and internationally, a two-step operation mechanism—first lifting and then rotating—is commonly used. Whether manual, pneumatic, or electric, this two-step operation results in a complex structure, large size, and gaps between the sealing surfaces after opening, making it easy for solid impurities in the medium to adhere. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a reciprocating lifting hard-seal plug valve.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a reciprocating lifting hard-seal plug valve, comprising a valve body, a mounting bracket, a plug body, a valve stem, and an operating device. The plug body is rotatably mounted within the valve body and engages with the sealing surface of the valve body. The valve stem is connected to the plug body and extends outside the valve body, and is connected to the operating device via the mounting bracket. The valve also includes a reciprocating lifting device; the reciprocating lifting device includes a drive ring, a guide ring, and a drive shaft; the drive ring is connected to the output end of the operating device and is driven to rotate by the operating device. The drive ring has a longitudinally straight... The guide ring is fixedly mounted on the mounting bracket and has a transverse slot. The bottom of the transverse slot has a continuously undulating slope structure, including a peak in the middle and valleys on both sides of the peak. One end of the drive shaft is connected to the valve stem, the middle part passes through the longitudinal straight groove of the drive ring, and the other end extends into the transverse slot of the guide ring. When the operating device drives the drive ring to rotate, the drive shaft rotates synchronously with the drive ring, and at the same time, one end of the drive shaft located in the transverse slot moves along the slope structure, forcing the valve stem to generate axial lifting and lowering motion while rotating.

[0005] Through the above technical solution, the reciprocating lifting device (drive ring, guide ring, drive shaft) and the special inclined structure are combined to force the valve stem to perform a continuous compound motion of "lifting → rotating → descending" during operation. This ensures that when the valve reaches the fully open or fully closed working position, the sealing surface of the plug body can be pressed tightly against the valve seat sealing surface again, eliminating the fixed gap between the sealing pairs. This fundamentally solves the technical problem of gaps in the open position of traditional lifting plug valves, which easily leads to the intrusion and adhesion of solid particles in the medium to the sealing surface. It greatly improves the sealing reliability and service life of the valve under harsh multiphase flow conditions such as delayed coking. At the same time, during the rotation, the plug body is in a lifted and separated state, effectively reducing the frictional resistance between the metal sealing surfaces, making the valve operation easier.

[0006] As a preferred embodiment of this utility model, a bearing is provided at one end of the drive shaft located in the transverse slot, and the outer ring of the bearing makes rolling contact with the slot wall of the transverse slot.

[0007] The above technical solutions significantly reduce the frictional resistance and wear of the drive shaft when it moves along the ramp structure, making the reciprocating lifting action smoother and more reliable, and improving the service life of related components.

[0008] As a preferred embodiment of this utility model, the bearing is a radial ball bearing.

[0009] As a preferred embodiment of this utility model, the drive shaft is provided with an installation step, and the bearing is limited and pressed against the installation step by a retaining ring.

[0010] The above technical solution ensures that the bearing is in a fixed position during operation and will not move axially or fall off, thereby guaranteeing the stability of power transmission and the accuracy of the entire reciprocating lifting motion.

[0011] As a preferred embodiment of the present invention, the reciprocating lifting device further includes a lifting rotating shaft, which is connected to the valve stem via a Haver sleeve.

[0012] The above technical solution constitutes a robust and reliable transmission connection structure. This split structure is easy to process, assemble, and maintain.

[0013] In a preferred embodiment of this invention, the drive shaft and the lifting rotation shaft are connected by a thread.

[0014] The above technical solution provides a simple, robust, and adjustable connection method that facilitates on-site installation and disassembly.

[0015] As a preferred embodiment of this utility model, the valve body is provided with a valve cover on the top, the mounting bracket includes a middle frame fixed on the valve cover and a protective bracket connected to the top of the middle frame, the guide ring is fixed between the middle frame and the protective bracket, and the driving component of the operating device is installed in the protective bracket and fixedly connected to the driving ring.

[0016] The above technical solutions have resulted in a modular and compact overall support and protection structure. The central frame connects the upper and lower sections, ensuring structural stability; the protective brackets effectively protect the internal drive rings and bearings.

[0017] As a preferred embodiment of this utility model, it further includes a sealing assembly for grinding the sealing surface; the sealing assembly includes a conical plug, a pull rod stud, and a push rod stud; the conical plug is used to detachably seal the notch on the sealing surface of the valve body; one end of the pull rod stud is threadedly connected to the conical plug, and the other end passes through a flange fixed to the end face of the valve body and is locked with a nut to tighten and fix the conical plug at the notch; one end of the push rod stud can abut against the end of the conical plug, and the other end passes through the flange and is locked with a nut.

[0018] Through the above technical solution, when grinding the inner conical sealing surface of the valve body, a removable conical plug is used to temporarily fill the gap on the sealing surface, so that the surface to be ground forms a complete and continuous inner conical surface. This ensures that the grinding head of the grinding machine can perform stable and continuous grinding, thereby greatly improving the geometric accuracy (roundness) and surface quality of the final machined valve seat sealing surface, laying a key manufacturing process foundation for the valve to achieve excellent hard sealing performance.

[0019] As a preferred embodiment of this utility model, it further includes a plurality of purge valves; the purge valves are installed on the valve body, their purge channels extend into the inner cavity of the valve body, and the outlet of the purge channel is directly opposite to the sealing pair area formed by the sealing surface of the plug body and the valve body.

[0020] The above technical solution allows for the periodic or on-demand injection of steam or inert gas through a purge valve to directly purge the sealing area, effectively preventing and removing any potentially accumulated coke particles or impurities. This maintains the cleanliness and sealing performance of the sealing surface over a long period, further extending the maintenance-free operation cycle of the valve under harsh conditions. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 yes Figure 1 A magnified view of part A; Figure 3 This is a cross-sectional view of the reciprocating lifting device in this utility model; Figure 4This is a cross-sectional view of the guide ring in this utility model; Figure 5 This is a cross-sectional view of the drive ring in this utility model; Figure 6 This is a schematic diagram of the drive shaft structure in this utility model; Figure 7 This is a half-sectional view of the valve body in this utility model; Figure 8 This is a schematic diagram of the sealing component in this utility model.

[0022] Reference numerals: 1. Valve body; 2. Mounting bracket; 3. Plug body; 4. Valve stem; 5. Operating device; 6. Sealing surface; 7. Drive ring; 8. Guide ring; 9. Drive shaft; 10. Longitudinal straight groove; 11. Transverse groove; 12. Slope peak; 13. Slope valley; 14. Bearing; 15. Mounting step; 16. Retaining ring; 17. Lifting and rotating shaft; 18. Haver sleeve; 19. Valve cover; 20. Middle frame; 21. Protective bracket; 22. Conical plug; 23. Tie rod stud; 24. Push rod stud; 25. Notch; 26. Nut; 27. Flange; 28. Purge valve. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0024] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" 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 a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0025] like Figure 1-8The reciprocating lifting type hard-seal plug valve shown includes a valve body 1, a mounting bracket 2, a plug body 3, a valve stem 4, and an operating device 5. The plug body 3 is rotatably installed inside the valve body 1 and cooperates with the sealing surface 6 of the valve body 1. The valve stem 4 is connected to the plug body 3 and extends to the outside of the valve body 1, and is connected to the operating device 5 through the mounting bracket 2. It also includes a reciprocating lifting device; the reciprocating lifting device includes a drive ring 7, a guide ring 8, and a drive shaft 9; the drive ring 7 is connected to the output end of the operating device 5 and is driven to rotate by the operating device 5; the drive ring 7 has a longitudinal straight groove 10 (preferably an oblong hole); the guide ring 8 is fixedly installed. The mounting bracket 2 has a transverse slot 11, the bottom of which is a continuously undulating slope structure, including a slope peak 12 in the middle and slope valleys 13 on both sides of the slope peak 12. One end of the drive shaft 9 is connected to the valve stem 4, the middle part passes through the longitudinal straight groove 10 of the drive ring 7, and the other end extends into the transverse slot 11 of the guide ring 8. When the operating device 5 drives the drive ring 7 to rotate, the drive shaft 9 rotates synchronously with the drive ring 7, and at the same time, one end of it located in the transverse slot 11 moves along the slope structure, forcing the valve stem 4 to generate axial lifting and lowering motion while rotating.

[0026] In a specific embodiment of this application, the operating device 5 exemplarily employs a handwheel drive device, the output end of which is directly connected to the drive ring 7 and drives it to rotate. The handwheel drive device is a well-known and mature mechanical structure in the art, and its specific construction is not an improvement of this invention; therefore, it will not be described in detail here. It is understood that, based on the same inventive concept, the operating device 5 can also be replaced with other drive forms well known to those skilled in the art, such as, but not limited to, electric devices, pneumatic devices, hydraulic devices, or any combination thereof. Any reciprocating lifting device structure described in this invention, regardless of the type of operating drive device used, falls within the protection scope of this application.

[0027] "Transmission connection" is a functional technical term used to define the power transmission relationship between the drive shaft 9 and the valve stem 4. It means that the torque and axial motion generated when the drive shaft 9 rotates can be effectively transmitted to the valve stem 4, thereby causing the valve stem 4 to perform corresponding rotation and lifting actions. The implementation of this "transmission connection" includes, but is not limited to, a direct connection between the drive shaft 9 and the valve stem 4, as well as an indirect connection through one or more intermediate transmission components (e.g., but not limited to, a lifting rotating shaft 17, a coupling, a gear set, etc.). Those skilled in the art will understand that any specific mechanical connection structure that can achieve the above-mentioned power transmission function falls within the scope of the term "transmission connection." This explanation aims to clarify the scope of protection of the claims and is consistent with the common understanding of those skilled in the art.

[0028] Through the cooperation of the reciprocating lifting device (drive ring 7, guide ring 8, drive shaft 9) and the special ramp structure, the valve stem 4 is forced to perform a continuous compound motion of "lifting → rotating → descending" during operation. This allows the sealing surface 6 of the plug body 3 to re-press and adhere to the valve seat sealing surface 6 when the valve reaches the fully open or fully closed working position, eliminating the fixed gap between the sealing pairs. This fundamentally solves the technical problem of gaps in the open position of traditional lifting plug valves, which easily leads to the intrusion and adhesion of solid particles in the medium to the sealing surface 6. It greatly improves the sealing reliability and service life of the valve under harsh multiphase flow conditions such as delayed coking. At the same time, during the rotation process, the plug body 3 is in a lifted and separated state, which effectively reduces the frictional resistance between the metal sealing surfaces 6, making the valve operation easier.

[0029] A bearing 14 is provided at one end of the drive shaft 9 located within the transverse groove 11. The outer ring of the bearing 14 rolls in contact with the groove wall of the transverse groove 11. This significantly reduces the frictional resistance and wear of the drive shaft 9 when moving along the inclined structure, making the reciprocating lifting action smoother and more reliable, and improving the service life of related components. In this embodiment, the bearing 14 is a radial ball bearing 14.

[0030] The drive shaft 9 is provided with a mounting step 15, and the bearing 14 is limited and pressed onto the mounting step 15 by a retaining ring 16. This ensures that the bearing 14 is fixed in position during operation and will not move axially or fall off, thereby guaranteeing the stability of power transmission and the accuracy of the entire reciprocating lifting motion.

[0031] The reciprocating lifting device also includes a lifting rotating shaft 17, which is connected to the valve stem 4 via a Haver sleeve 18, forming a robust and reliable transmission connection structure. This split structure facilitates processing, assembly, and subsequent maintenance.

[0032] The drive shaft 9 and the lifting and rotating shaft 17 are connected by threads, providing a simple, robust and adjustable connection method that facilitates on-site installation and disassembly.

[0033] The valve body 1 has a valve cover 19 on its top. The mounting bracket 2 includes a central frame 20 fixed to the valve cover 19 and a protective bracket 21 connected to the top of the central frame 20. The guide ring 8 is fixed between the central frame 20 and the protective bracket 21. The driving component of the operating device 5 is installed inside the protective bracket 21 and fixedly connected to the driving ring 7. This forms a modular and compact overall support and protection structure. The central frame 20 provides structural stability and supports the upper and lower parts of the structure; the protective bracket 21 effectively protects the internal driving ring 7 and bearing 14.

[0034] It also includes a sealing assembly for the grinding process of the sealing surface 6, which facilitates the grinding of the inner conical surface of the valve body 1; the sealing assembly includes a conical plug 22, a pull rod stud 23, and a push rod stud 24; the conical plug 22 is used to detachably seal the notch 25 on the sealing surface 6 of the valve body 1; one end of the pull rod stud 23 is threaded to the conical plug 22, and the other end passes through the flange 27 fixed to the end face of the valve body 1, and is locked by a nut 26 to tighten and fix the conical plug 22 to the notch 25; one end of the push rod stud 24 can abut against the end of the conical plug 22, and the other end passes through the flange 27 and is locked by a nut 26. In this embodiment, the sealing assembly is preferably in two sets, located on the left and right sides of the valve body 1 respectively.

[0035] When grinding the inner conical sealing surface 6 of the valve body 1 (when grinding the sealing surface 6 of the valve body 1 using a vertical internal cylindrical grinder), a removable conical plug 22 temporarily fills the gap 25 on the sealing surface 6, making the surface to be ground a complete and continuous inner conical surface. This ensures that the grinding head of the grinding machine can perform stable and continuous grinding, thereby greatly improving the geometric accuracy (roundness) and surface quality of the finally machined valve seat sealing surface 6, laying a key manufacturing process foundation for the valve to achieve excellent hard sealing performance.

[0036] It also includes several purge valves 28; the purge valves 28 are mounted on the valve body 1, and their purge channels extend into the inner cavity of the valve body 1, with the outlet of the purge channel facing the sealing pair area formed by the plug body 3 and the sealing surface 6 of the valve body 1. Steam or inert gas can be injected periodically or as needed through the purge valves 28 to directly purge the sealing pair area, effectively preventing and removing any coke particles or impurities that may accumulate, thereby maintaining the cleanliness and sealing performance of the sealing surface 6 for a long time, and further extending the maintenance-free operation cycle of the valve under harsh working conditions.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the utility model as defined by the appended claims and their equivalents.

Claims

1. A reciprocating lifting hard-seal plug valve, comprising a valve body (1), a mounting bracket (2), a plug body (3), a valve stem (4), and an operating device (5), wherein the plug body (3) is rotatably mounted inside the valve body (1) and cooperates with the sealing surface (6) of the valve body (1), and the valve stem (4) is connected to the plug body (3) and extends to the outside of the valve body (1), and is connected to the operating device (5) through the mounting bracket (2), characterized in that, It also includes a reciprocating lifting device; the reciprocating lifting device includes a drive ring (7), a guide ring (8) and a drive shaft (9); the drive ring (7) is connected to the output end of the operating device (5) and is driven to rotate by the operating device (5), and a longitudinal straight groove (10) is provided on the drive ring (7); the guide ring (8) is fixedly set on the mounting bracket (2), and a transverse hole groove (11) is provided on it, the bottom of the transverse hole groove (11) is a continuously undulating slope structure, including a slope peak (12) located in the middle and a position The valleys (13) on both sides of the slope peak (12); one end of the drive shaft (9) is connected to the valve stem (4) for transmission, the middle part passes through the longitudinal straight groove (10) of the drive ring (7), and the other end extends into the transverse hole groove (11) of the guide ring (8); when the operating device (5) drives the drive ring (7) to rotate, the drive shaft (9) rotates synchronously with the drive ring (7), and at the same time, one end of it located in the transverse hole groove (11) moves along the slope structure, forcing the valve stem (4) to generate axial lifting and lowering motion while rotating.

2. The reciprocating lifting hard-seal plug valve according to claim 1, characterized in that: The drive shaft (9) is provided with a bearing (14) at one end located in the transverse slot (11), and the outer ring of the bearing (14) is in rolling contact with the slot wall of the transverse slot (11).

3. The reciprocating lifting hard-seal plug valve according to claim 2, characterized in that: The bearing (14) is a radial ball bearing (14).

4. The reciprocating lifting hard-seal plug valve according to claim 2 or 3, characterized in that: The drive shaft (9) is provided with an installation step (15), and the bearing (14) is limited and pressed against the installation step (15) by a retaining ring (16).

5. The reciprocating lifting hard-seal plug valve according to claim 1, characterized in that: The reciprocating lifting device also includes a lifting rotating shaft (17), which is connected to the valve stem (4) via a Haver sleeve (18).

6. The reciprocating lifting hard-seal plug valve according to claim 5, characterized in that: The drive shaft (9) is connected to the lifting rotation shaft (17) by a thread.

7. The reciprocating lifting hard-seal plug valve according to claim 1, characterized in that: The valve body (1) is provided with a valve cover (19) on the top. The mounting bracket (2) includes a middle frame (20) fixed on the valve cover (19) and a protective bracket (21) connected to the top of the middle frame (20). The guide ring (8) is fixed between the middle frame (20) and the protective bracket (21). The driving component of the operating device (5) is installed in the protective bracket (21) and fixedly connected to the driving ring (7).

8. The reciprocating lifting hard-seal plug valve according to claim 1, characterized in that: It also includes a sealing assembly for grinding the sealing surface (6); the sealing assembly includes a conical plug (22), a tie rod stud (23) and a push rod stud (24); the conical plug (22) is used to detachably seal the notch (25) on the sealing surface (6) of the valve body (1); one end of the tie rod stud (23) is threaded to the conical plug (22), and the other end passes through the flange (27) fixed to the end face of the valve body (1) and is locked by a nut (26) to tighten and fix the conical plug (22) to the notch (25); one end of the push rod stud (24) can abut against the end of the conical plug (22), and the other end passes through the flange (27) and is locked by a nut (26).

9. The reciprocating lifting hard-seal plug valve according to claim 1, characterized in that: It also includes several purge valves (28); the purge valves (28) are installed on the valve body (1), and their purge channels extend into the inner cavity of the valve body (1), and the outlet of the purge channels is directly opposite to the sealing pair area formed by the plug body (3) and the sealing surface (6) of the valve body (1).

Images