Pneumatic diaphragm actuator for track ball valve
Patent Information
- Application Number
- CN202522306114.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-31
- Publication Date
- 2026-09-25
- Estimated Expiration
- 2035-10-31
AI Technical Summary
[0003]本申请的目的在于提供一种轨道球阀用气动薄膜执行机构，以解决轨道球阀常规配套气动活塞式或电动执行机构，存在结构复杂、成本较高和响应速度受限的问题
[0009]与现有技术相比，本实用新型所提供的一种轨道球阀用气动薄膜执行机构，装配工人从下腔螺塞孔注入液压油，液压油从油路进入油缸腔内，操作人员再将气源管接入下膜盖气源接头和上膜盖气源接头处，并连接切换气路的部件，当下膜盖气源接头进气后，推杆带动阀杆向上动作将阀门打开，当上膜盖气源接头进气后，推杆带动阀杆向下动作将阀门关闭，此过程中通过调控调节螺钉控制液压油的流速，对执行机构动作速度进行控制，液压缓冲装置还可对执行机构起缓冲作用。该气动薄膜执行机构采用高灵敏度的膜片设计，能够快速响应气压变化，实现精确控制，在相同推力需求下，气动薄膜执行机构相比活塞式设计，在保证运行平稳的前提下气动薄膜执行机构成本更低。下膜盖、上膜盖以及膜片等各部件独立可更换，可提高装配效率与维护便捷性。
Smart Images
Figure CN224801087U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of track ball valve application technology, and in particular to a pneumatic diaphragm actuator for track ball valves. Background Technology
[0002] The orbit ball valve is a new type of valve, belonging to the same category as the gate valve. It is mainly used for cutting off and controlling fluid flow, offering advantages such as frictionless opening and excellent sealing performance. Its closing element is a ball that rotates around the valve body's centerline to open and close. Compared to traditional valves, the orbit ball valve eliminates friction during opening and closing, reducing wear and extending service life. It is widely used in industries such as petroleum, chemical, and natural gas. However, currently, orbit ball valves are conventionally equipped with pneumatic piston or electric actuators, which suffer from problems such as complex structure, high cost, and limited response speed. Utility Model Content
[0003] The purpose of this application is to provide a pneumatic diaphragm actuator for a track ball valve, so as to solve the problems of complex structure, high cost and limited response speed of conventional pneumatic piston or electric actuators for track ball valves.
[0004] To solve the above-mentioned technical problems, this application provides a pneumatic diaphragm actuator for a track ball valve, comprising: The system comprises a support frame, a lower membrane cover, an upper membrane cover corresponding to the lower membrane cover, and a membrane sheet located within the lower and upper membrane covers. An upper tray and a lower tray are respectively installed on both sides of the membrane sheet. A limiting component is installed on the lower side of the lower tray. The lower membrane cover is installed on the support frame by a second rubber-coated bolt. The lower membrane cover, the upper membrane cover, and the membrane sheet are fixed together by eye bolts. A hexagonal nut is provided at the lower end of the eye bolts. A hydraulic buffer device is installed on the upper membrane cover by a first rubber-coated bolt. The hydraulic buffer device is equipped with an adjusting rod that penetrates the upper membrane cover and extends into the upper mold cavity. The lower end of the adjusting rod is connected to a push rod that passes through the upper tray, the diaphragm, the lower tray, the limiting member, and the lower membrane cover in sequence. The limiting member is located at the upper step of the push rod. A second locking nut is installed on the push rod above the upper tray. A guide sleeve is threadedly connected to the connection between the lower membrane cover and the push rod. A first O-ring is provided at the contact position between the lower membrane cover and the guide sleeve. A first guide band and a second O-ring are installed in the center hole of the guide sleeve. A fifth O-ring is provided at the connection between the lower tray and the push rod. A valve stem extending to the outside of the bracket is fixed to the lower end of the push rod. The lower membrane cover is provided with a lower membrane cover air source connector on its lower side, and the upper membrane cover is provided with an upper membrane cover air source connector on its upper side.
[0005] In a preferred embodiment, a pneumatic diaphragm actuator for a track ball valve is provided with an anti-rotation screw on one side of the guide sleeve; Correspondingly, a vertical groove is also provided on one side of the push rod, and the front end of the anti-rotation screw is located in the vertical groove.
[0006] In a preferred embodiment, a pneumatic diaphragm actuator for a track ball valve is provided, wherein a pointer ring is mounted on the push rod near its lower end via a set screw, and a pointer is provided on one side of the pointer ring; Correspondingly, the inner side of the bracket is provided with a travel indicator point corresponding to the pointer.
[0007] In a preferred embodiment, a pneumatic diaphragm actuator for a track ball valve includes a hydraulic buffer device comprising a lower cylinder cover connected to the upper diaphragm cover via a first rubber-coated bolt and a cylinder connected to the lower cylinder cover. An upper cylinder cover is mounted on the top of the cylinder via hexagonal head bolts. Oil passages communicating with the lower and upper chambers of the cylinder are provided on the cylinder and the upper cylinder cover. A piston is installed inside the cylinder. The upper end of an adjusting rod is connected to the piston via a locking bolt. A third O-ring seals the adjusting rod and the piston. An upper chamber plug is installed at one end of the upper cylinder cover, a lower chamber plug is installed on one side of the cylinder, and an adjusting screw is installed in an adjusting hole on the other side of the cylinder. The adjusting hole communicates with the oil passages, and a first locking nut is provided on the adjusting screw.
[0008] The solution requires detailed explanation of a pneumatic diaphragm actuator for a track ball valve, wherein the lower end cover of the cylinder and the upper diaphragm cover are sealed by a fourth O-ring, a ninth O-ring and a second guide band are provided at the connection between the lower end cover of the cylinder and the adjusting rod, a sixth O-ring is provided at the contact position between the piston and the cylinder, and a seventh and an eighth O-ring are provided between the upper cylinder cover and the cylinder.
[0009] Compared with existing technologies, the pneumatic diaphragm actuator for a track ball valve provided by this utility model allows the assembly worker to inject hydraulic oil through the screw plug hole in the lower chamber. The hydraulic oil enters the cylinder chamber through the oil circuit. The operator then connects the air supply pipe to the air supply connectors of the lower and upper diaphragm covers, and connects the air circuit switching component. When air enters through the lower diaphragm cover air supply connector, the push rod drives the valve stem upward to open the valve. When air enters through the upper diaphragm cover air supply connector, the push rod drives the valve stem downward to close the valve. During this process, the flow rate of the hydraulic oil is controlled by adjusting the adjusting screw, thereby controlling the action speed of the actuator. The hydraulic buffer device also provides a buffering effect for the actuator. This pneumatic diaphragm actuator adopts a high-sensitivity diaphragm design, which can quickly respond to changes in air pressure and achieve precise control. Under the same thrust requirement, the pneumatic diaphragm actuator is less expensive than the piston design while ensuring stable operation. The lower diaphragm cover, upper diaphragm cover, and diaphragm are all independently replaceable, which improves assembly efficiency and maintenance convenience. Attached Figure Description
[0010] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.
[0011] Figure 1 This is a schematic diagram of a pneumatic diaphragm actuator for a track ball valve provided in an embodiment of this application; Figure 2 This is a schematic diagram of another pneumatic diaphragm actuator for a track ball valve provided in an embodiment of this application; In the diagram: 1. Bracket; 2. Valve stem; 3. Set screw; 4. Push rod; 5. Guide sleeve; 6. First O-ring; 7. First guide band; 8. Second O-ring; 9. Lower tray; 10. Diaphragm; 11. Upper tray; 12. First lock nut; 13. Upper chamber plug; 14. Locking bolt; 15. Third O-ring; 16. Upper cylinder head; 17. Hex head bolt; 18. Hydraulic cylinder; 180° oil passage; 19. Lower chamber plug; 20. Fourth O-ring; 21. First rubber-coated bolt; 22. Eye bolt; 23. Hex head bolt 24. Limiting component; 25. Fifth O-ring; 26. Anti-rotation screw; 27. Pointer; 270. Stroke indicator point; 28. Pointer ring; 29. Lower membrane cover air supply connector; 30. Lower membrane cover; 31. Upper membrane cover; 32. Upper membrane cover air supply connector; 33. Adjusting screw; 34. Sixth O-ring; 35. Seventh O-ring; 36. Eighth O-ring; 37. Piston; 38. Second guide belt; 39. Ninth O-ring; 40. Adjusting rod; 41. Lower end cover of cylinder; 42. Second locking nut; 43. Second rubber-coated bolt. Detailed Implementation
[0012] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.
[0013] The core of this application is to provide a pneumatic diaphragm actuator for a track ball valve, which solves the problems of complex structure, high cost and limited response speed of conventional pneumatic piston or electric actuators for track ball valves.
[0014] Figure 1 This is a schematic diagram of a pneumatic diaphragm actuator for a track ball valve provided in an embodiment of this application. Figure 2 This is a schematic diagram of another pneumatic diaphragm actuator for a track ball valve provided in an embodiment of this application. Figure 1 The image shows the valve in its fully open position. Figure 2 The image shows the valve in the fully closed state. See [link / reference]. Figures 1 to 2 As shown.
[0015] Example 1 A pneumatic diaphragm actuator for a ball valve includes a bracket 1, a lower diaphragm cover 30, an upper diaphragm cover 31 corresponding to the lower diaphragm cover 30, and a diaphragm 10 located inside the lower diaphragm cover 30 and the upper diaphragm cover 31. An upper tray 11 and a lower tray 9 are respectively installed on both sides of the diaphragm 10. The installation of the upper tray 11 and the lower tray 9 on both sides of the diaphragm 10 can reduce the force-bearing area of the diaphragm 10 and distribute part of the air source pressure on the end faces of the upper tray 11 and the lower tray 9. A lower diaphragm cover air source connector 29 is provided on the lower side of the lower diaphragm cover 30, and an upper diaphragm cover air source connector 32 is provided on the upper side of the upper diaphragm cover 31. A limiting member 24 is installed on the lower side of the lower tray 9. When the air source enters the upper diaphragm cavity from the upper diaphragm cover air source connector 32, the limiting member 24 can limit the closed position of the actuator. The lower membrane cover 30 is mounted on the bracket 1 by the second rubber-coated bolt 43. The lower membrane cover 30, the upper membrane cover 31 and the diaphragm 10 are fixed together by eye bolts 22. The lower end of the eye bolt 22 is provided with a hexagonal nut 23. In actual installation, mounting holes are also machined around the lower membrane cover 30 and the upper membrane cover 31. Hexagonal head bolts and nuts are installed in the mounting holes to further lock the upper membrane cover 31, the lower membrane cover 30 and the diaphragm 10. The mounting holes and the hexagonal head bolts and nuts here are not shown in the figure. A hydraulic buffer device is mounted on the upper membrane cover 31 by the first rubber-coated bolt 21. An adjusting rod 40 is installed on the hydraulic buffer device, penetrating the upper diaphragm cover 31 and extending into the upper mold cavity. The lower end of the adjusting rod 40 is connected to a push rod 4 that sequentially passes through the upper tray 11, diaphragm 10, lower tray 9, limiting member 24, and lower diaphragm cover 30. The limiting member 24 is located at the upper step of the push rod 4. A second locking nut 42 is installed on the push rod 4, located above the upper tray 11. The second locking nut 42 can lock the upper tray 11, lower tray 9, diaphragm 10, and limiting member 24. Specifically, the upper radius of the push rod 4 is small, and a step is formed at its upper end. An external thread is machined at the upper end of the push rod 4. An internal thread is machined on the adjusting rod 40, which is connected to the external thread at the upper end of the push rod 4. By adjusting the threaded connection length between the adjusting rod 40 and the push rod 4, the opening degree of the actuator can be adjusted.
[0016] A guide sleeve 5 is threadedly connected to the lower membrane cover 30 and the push rod 4. A first O-ring 6 is provided at the contact position between the lower membrane cover 30 and the guide sleeve 5 for sealing. A first guide band 7 and a second O-ring 8 are installed in the center hole of the guide sleeve 5 for sealing. The guide sleeve 5 and the lower membrane cover 30 are locked together by threads to prevent the guide sleeve 5 from rotating radially when the push rod 4 moves axially. A fifth O-ring 25 is provided at the connection between the lower tray 9 and the push rod 4. A valve stem 2 extending to the outside of the bracket 1 is fixed to the lower end of the push rod 4.
[0017] Example 2 Based on Embodiment 1, a pneumatic diaphragm actuator for a track ball valve includes an anti-rotation screw 26 on one side of the guide sleeve 5; correspondingly, a vertical groove is provided on one side of the push rod 4, with the front end of the anti-rotation screw 26 located within the vertical groove. The guide sleeve 5 has a threaded hole that penetrates its central hole. The anti-rotation screw 26 is inserted into the threaded hole, and its cylindrical front end is embedded in the vertical groove on the push rod 4. When the push rod 4 moves axially, the anti-rotation screw 26 prevents the push rod 4 from rotating.
[0018] Based on Embodiment 1, a pneumatic diaphragm actuator for a track ball valve includes a pointer ring 28 mounted on the lower end of the push rod 4 via a set screw 3. A pointer 27 is provided on one side of the pointer ring 28. Correspondingly, a stroke indicator point 270 corresponding to the pointer 27 is provided on the inner side of the bracket 1. Specifically, the pointer 27 is installed in a countersunk hole on the outer periphery of the pointer ring 28. During the movement of the pointer 27 driven by the push rod 4, the stroke indicator point 270 can be used to indicate the stroke of the actuator through the pointer 27. The set screw 3 is inserted into the threaded hole on the outer periphery of the pointer ring 28 to lock it after adjusting the position of the pointer ring 28.
[0019] Example 3 Based on Embodiment 1, a pneumatic diaphragm actuator for a track ball valve includes a hydraulic buffer device comprising a lower cylinder cover 41 connected to an upper diaphragm cover 31 via a first rubber-coated bolt 21 and a cylinder 18 connected to the lower cylinder cover 41. An upper cylinder cover 16 is mounted on the top of the cylinder 18 via a hexagonal head bolt 17. An oil passage 180 communicating with the lower and upper chambers of the cylinder is provided on the cylinder 18 and the upper cylinder cover 16. A piston 37 is installed inside the cylinder 18. The upper end of an adjusting rod 40 is connected to the piston 37 via a locking bolt 14. The adjusting rod 40 and the piston 37 are sealed by a third O-ring 15. An upper chamber plug 13 is installed at one end of the upper cylinder cover 16, a lower chamber plug 19 is installed on one side of the cylinder 18, and an adjusting screw 33 is installed in the adjusting hole on the other side of the cylinder 18. The adjusting hole communicates with the oil passage 180, and a first locking nut 12 is provided on the adjusting screw 33.
[0020] Based on Embodiment 3, a pneumatic diaphragm actuator for a track ball valve is provided, wherein the lower end cover 41 of the cylinder and the upper diaphragm cover 31 are sealed by a fourth O-ring 20, a ninth O-ring 39 and a second guide strip 38 are provided at the connection between the lower end cover 41 of the cylinder and the adjusting rod 40, a sixth O-ring 34 is provided at the contact position between the piston 37 and the cylinder 18, and a seventh O-ring 35 and an eighth O-ring 36 are provided between the upper cylinder cover 16 and the cylinder 18. The adjusting rod 40 passes through the center hole of the lower end cover 41 of the cylinder. The center hole of the lower end cover 41 of the cylinder has a hole for mounting the second guide belt 38. The second guide belt 38 guides the adjusting rod 40 and can also compensate for the coaxiality error of the parts. The center hole of the lower end cover 41 of the cylinder also has an O-ring groove, into which the ninth O-ring 39 is installed to seal the adjusting rod 40. The upper end of the adjusting rod 40 is positioned with the end face of the cylinder. The locking bolt 14 is threaded into the internal thread hole at the upper end of the adjusting rod 40, which moves the piston 37. The adjusting screw 33 adjusts the flow rate of the hydraulic oil in the two chambers of the piston 37 through the front conical surface, thereby adjusting the action speed of the hydraulic buffer device.
[0021] To enable those skilled in the art to better understand this solution, the following is combined with... Figure 1 and Figure 2 The assembly process of the pneumatic diaphragm actuator provided in this embodiment is described in detail below: First, the first O-ring 6 is installed in the countersunk hole on the upper end face of the bracket 1. The first guide belt 7 and the second O-ring 8 are installed in the center hole of the guide sleeve 5. The guide sleeve 5 in the assembled guide sleeve component is installed in the threaded hole machined at the center position of the lower film cover 30 through the external thread machined on its upper part. The lower film cover 30 and the assembled guide sleeve component are assembled into a whole. The lower film cover 30 is installed on the bracket 1 by the second rubber-coated bolt 43.
[0022] Next, with the opening of the limiting member 24 facing downwards, the push rod 4 passes through the center hole on the limiting member 24. Then, the fifth O-ring 25 is installed into the countersunk hole of the lower tray 9. The diaphragm 10 is installed on the upper side of the lower tray 9 with its opening facing downwards. The upper tray 11 is then fitted with the outer cylindrical circle of the upper part of the push rod 4, and the upper tray 11 is pressed onto the upper side of the diaphragm 10. The second locking nut 42 is installed on the push rod 4 to lock the upper tray 11, the lower tray 9, the diaphragm 10, and the limiting member 24. The adjusting rod 40 is threadedly connected to the push rod 4 and assembled together. The upper end of the adjusting rod 40 passes through the center hole of the lower flange of the oil cylinder 18. The two are sealed and guided by the ninth O-ring 39 and the second guide band 38. The locking bolt 14 passes through the center hole of the piston 37 and is threadedly connected to the adjusting rod 40 and assembled together. The two are sealed by the third O-ring 15.
[0023] In use, hydraulic oil is injected into the inner cavity of the cylinder 18 through the screw holes where the lower chamber screw plug 19 and the upper chamber screw plug 13 are located. The flow rate of the hydraulic oil is adjusted by the conical surface at the front end of the adjusting screw 33, which controls the flow rate of the hydraulic oil in the cylinder and adjusts the buffering force of the hydraulic buffer device on the actuator. After setting the position of the adjusting screw 33, the first locking nut 12 is tightened. Compressed air is introduced into the lower diaphragm cover 30 and the upper diaphragm cover 31 through the lower diaphragm cover air source connector 29 and the upper diaphragm cover air source connector 32. The air source pressure serves as the power source. During this process, the diaphragm 10, the lower tray 9, and the upper tray 11 are pushed, causing the push rod 4 to move axially. To prevent the push rod 4 from rotating, an anti-rotation screw 26 is installed in a threaded hole machined on the lower outer circumference of the guide sleeve 5. The cylindrical head of the anti-rotation screw 26 slides in a vertical groove machined on the push rod 4. A pointer ring 28 is mounted on the push rod 4, and the pointer ring 28 and the push rod 4 are locked together by a set screw 3. The pointer 27 is inserted into a countersunk hole machined on the pointer ring 28. The pointer 27 moves axially with the pointer ring 28 to indicate the stroke of the actuator. When the actuator push rod 4 moves axially, it drives the valve stem 2 to move together, thereby controlling the opening and closing of the valve.
[0024] This utility model provides a pneumatic diaphragm actuator for a track ball valve. The assembly worker injects hydraulic oil through the lower chamber plug hole, and the hydraulic oil enters the cylinder chamber through the oil circuit. The operator then connects the air supply pipe to the lower diaphragm cover air supply connector and the upper diaphragm cover air supply connector, and connects the air circuit switching component. When air enters through the lower diaphragm cover air supply connector, the push rod drives the valve stem upward to open the valve. When air enters through the upper diaphragm cover air supply connector, the push rod drives the valve stem downward to close the valve. During this process, the flow rate of the hydraulic oil is controlled by adjusting the adjusting screw, thereby controlling the actuator's operating speed. The hydraulic buffer device also provides a buffering effect for the actuator. This pneumatic diaphragm actuator adopts a high-sensitivity diaphragm design, which can quickly respond to changes in air pressure and achieve precise control. Under the same thrust requirement, compared with the piston design, the pneumatic diaphragm actuator has a lower cost while ensuring stable operation. The lower diaphragm cover, upper diaphragm cover, and diaphragm are all replaceable, which improves assembly efficiency and maintenance convenience. It also breaks through structural limitations to achieve a compact and lightweight design, improves valve sensitivity, and enables precise valve control, facilitating mass production and assembly.
[0025] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and incorporate common knowledge or customary techniques in the art disclosed herein. The specification and examples are to be considered exemplary only, and the true scope of this application is indicated by the claims.
[0026] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The embodiments of this application described above do not constitute a limitation on the scope of protection of this application.
Claims
1. A pneumatic diaphragm actuator for a track ball valve, characterized in that, include: The bracket (1), the lower membrane cover (30), the upper membrane cover (31) corresponding to the lower membrane cover (30), and the membrane (10) located in the lower membrane cover (30) and the upper membrane cover (31) are respectively equipped with an upper tray (11) and a lower tray (9) on both sides of the membrane (10). A limiting member (24) is installed on the lower side of the lower tray (9). The lower membrane cover (30) is installed on the bracket (1) by a second rubber-coated bolt (43). The lower membrane cover (30), the upper membrane cover (31) and the membrane (10) are fixed together by a lifting eye screw (22). A hexagonal nut (23) is provided at the lower end of the lifting eye screw (22). A hydraulic buffer device is installed on the upper membrane cover (31) by a first rubber-coated bolt (21). The hydraulic buffer device is equipped with an adjusting rod (40) that penetrates the upper membrane cover (31) and extends into the upper mold cavity. The lower end of the adjusting rod (40) is connected to a push rod (4) that passes through the upper tray (11), the diaphragm (10), the lower tray (9), the limiting member (24), and the lower membrane cover (30) in sequence. The limiting member (24) is located at the upper step of the push rod (4). A second locking nut (4) located above the upper tray (11) is installed on the push rod (4). 2) A guide sleeve (5) is threadedly connected to the connection between the lower membrane cover (30) and the push rod (4). A first O-ring (6) is provided at the contact position between the lower membrane cover (30) and the guide sleeve (5). A first guide band (7) and a second O-ring (8) are installed in the center hole of the guide sleeve (5). A fifth O-ring (25) is provided at the connection between the lower tray (9) and the push rod (4). A valve stem (2) extending to the outside of the bracket (1) is fixed at the lower end of the push rod (4). The lower membrane cover (30) is provided with a lower membrane cover air source connector (29) on its lower side, and the upper membrane cover (31) is provided with an upper membrane cover air source connector (32) on its upper side.
2. The pneumatic diaphragm actuator for a track ball valve according to claim 1, characterized in that, An anti-rotation screw (26) is also provided on one side of the guide sleeve (5). Correspondingly, a vertical groove is also provided on one side of the push rod (4), and the front end of the anti-rotation screw (26) is located in the vertical groove.
3. The pneumatic diaphragm actuator for a track ball valve according to claim 1, characterized in that, The push rod (4) is also equipped with a pointer ring (28) near its lower end by a set screw (3), and a pointer (27) is provided on one side of the pointer ring (28). Correspondingly, the inner side of the bracket (1) is provided with a travel indicator point (270) corresponding to the pointer (27).
4. The pneumatic diaphragm actuator for a track ball valve according to claim 1, characterized in that, The hydraulic buffer device includes a lower cylinder cover (41) connected to the upper diaphragm cover (31) via the first rubber-coated bolt (21) and a cylinder (18) connected to the lower cylinder cover (41). An upper cylinder cover (16) is mounted on the top of the cylinder (18) via hexagonal head bolts (17). Oil passages (180) communicating with the lower and upper chambers of the cylinder are provided on the cylinder (18) and the upper cylinder cover (16). A piston (37) is installed inside the cylinder (18). The upper end of the adjusting rod (40)... The piston (37) is connected by a locking bolt (14). The adjusting rod (40) and the piston (37) are sealed by a third O-ring (15). An upper chamber plug (13) is installed at one end of the upper cylinder cover (16). A lower chamber plug (19) is installed on one side of the oil cylinder (18). An adjusting screw (33) is installed in the adjusting hole on the other side of the oil cylinder (18). The adjusting hole is connected to the oil passage (180). A first locking nut (12) is provided on the adjusting screw (33).
5. The pneumatic diaphragm actuator for a track ball valve according to claim 4, characterized in that, The lower end cover (41) of the cylinder and the upper membrane cover (31) are sealed by a fourth O-ring (20). A ninth O-ring (39) and a second guide strip (38) are also provided at the connection between the lower end cover (41) of the cylinder and the adjusting rod (40). A sixth O-ring (34) is also provided at the contact position between the piston (37) and the cylinder (18). A seventh O-ring (35) and an eighth O-ring (36) are also provided between the upper cylinder cover (16) and the cylinder (18).