Shaft seal structure capable of being replaced on line for butterfly valve

Abstract

The utility model discloses a shaft seal structure capable of being replaced on line for a butterfly valve in the technical field of butterfly valves, which comprises a butterfly valve main body, a valve shaft assembled inside the butterfly valve main body, a shaft shoulder arranged between the butterfly valve main body and the valve shaft, a shaft sleeve shaft shoulder arranged at the upper end of the shaft shoulder, a quick release hole assembled at the upper end of the shaft sleeve shaft shoulder, and a shaft sleeve pressing plate assembled outside the valve shaft. A pressing plate fixing screw is assembled between the shaft sleeve pressing plate and the butterfly valve body, the valve shaft is sleeved with an O-shaped ring and a quick-release shaft sleeve, a fixing hole is formed in the position, located at the pressing plate fixing screw, of the butterfly valve body, a fastening cylinder is installed in the fixing hole, a fastening rod is installed in the fastening cylinder, and a fastening groove is formed in the bottom end of the pressing plate fixing screw. The pressing plate fixing screws are connected to the outer portions of the fastening rods in a sleeving mode through the fastening grooves. The shaft seal structure capable of being replaced on line for the butterfly valve is reasonable in structural design, seal can be replaced on line, the valve does not need to be disassembled or the valve shaft does not need to be moved, torque is small and stable, and a seal structure and a valve shaft blow-out prevention structure are integrated.

Description

Technical Field

[0001] The utility model relates to the technical field of butterfly valves, in particular to an on-line replaceable shaft seal structure for a butterfly valve. Background Technique

[0002] A butterfly valve, also called a flap valve, is a simple regulating valve that uses a disc-shaped opening and closing member to reciprocate and rotate about 90° to open, close or regulate the flow rate of a medium. The valve can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil products, liquid metals and radioactive media. The butterfly valve not only has a simple structure, small size, light weight, low material consumption, small installation size, small driving torque, simple and rapid operation, but also can simultaneously have good flow regulation function and closing and sealing characteristics. It is one of the fastest-developing valve varieties in the past decade or so. The use of butterfly valves is very extensive. The varieties and quantities used are still continuing to expand, and are developing towards high temperature, high pressure, large diameter, high sealing performance, long life, excellent regulation characteristics, and multi-function of one valve. Its reliability and other performance indicators have reached a relatively high level. With the application of chemical-resistant synthetic rubber on butterfly valves, the performance of butterfly valves has been improved. Since synthetic rubber has the characteristics of corrosion resistance, erosion resistance, dimensional stability, good resilience, easy forming, low cost, etc., and different synthetic rubbers with different performances can be selected according to different usage requirements to meet the working conditions of butterfly valves. Currently, synthetic rubber is mainly used on the valve seats of butterfly valves;

[0003] However, for the O-ring of the current butterfly valve shaft sleeve: the seal cannot be replaced online, and for the packing seal: the compression amount is not easy to accurately adjust, the generated torque is large, and it has the function of online adjusting the compression amount, but it cannot be replaced online. Therefore, the existing technology needs to be improved. Content of the Utility Model

[0004] The purpose of the utility model is to provide an integrally vulcanized rubber valve seat for a butterfly valve to solve the problems of the O-ring of the current butterfly valve shaft sleeve: the seal cannot be replaced online, and for the packing seal: the compression amount is not easy to accurately adjust, the generated torque is large, and it has the function of online adjusting the compression amount, but it cannot be replaced online as mentioned in the above background technique.

[0005] To achieve the above object, the present utility model provides the following technical solution: A shaft seal structure for a butterfly valve that can be replaced online, including a butterfly valve body. A valve shaft is assembled inside the butterfly valve body. There is a shaft shoulder between the butterfly valve body and the valve shaft. An axial sleeve shaft shoulder is provided at the upper end of the shaft shoulder. A quick-release hole is assembled at the upper end of the axial sleeve shaft shoulder. An axial sleeve pressing plate is assembled outside the valve shaft. A pressing plate fixing screw is assembled between the axial sleeve pressing plate and the butterfly valve body. An O-ring is sleeved outside the valve shaft. A quick-release axial sleeve is sleeved outside the valve shaft. The butterfly valve body is provided with a fixing hole at the position of the pressing plate fixing screw, and a fastening cylinder is installed in the fixing hole. A fastening rod is installed in the fastening cylinder. A fastening groove is provided at the bottom end of the pressing plate fixing screw. The pressing plate fixing screw is sleeved outside the fastening rod through the fastening groove.

[0006] Preferably, three limiting columns are assembled on the outer wall of the fastening cylinder. The three limiting columns are distributed in a triangular shape. A spiral groove that matches the external thread of the pressing plate fixing screw is provided on the outer wall of the limiting column. A fastening nut is sleeved outside the pressing plate fixing screw.

[0007] Preferably, an annular groove is provided at the bottom end of the fastening nut. The top end of the limiting column is arranged in the annular groove.

[0008] Preferably, a fixing ring is fixedly installed at the upper end outside the pressing plate fixing screw. An annular pressing piece, a spring and an annular rubber piece are sleeved on the circumferential surface of the pressing plate fixing screw.

[0009] Preferably, an extrusion block is fixedly installed at the lower edge of the annular pressing piece.

[0010] Preferably, an external thread is provided on the outer wall of the fastening rod. An internal thread that matches the external thread is provided on the inner wall of the fastening cylinder.

[0011] Preferably, the outer diameter of the axial sleeve shaft shoulder is larger than the inner diameter of the quick-release axial sleeve.

[0012] Compared with the prior art, the beneficial effect of the present utility model is: The shaft seal structure for a butterfly valve that can be replaced online has a reasonable structural design, can replace the seal online, does not require disassembling the valve or moving the valve shaft, has a small and stable torque, and integrates a sealing and valve shaft anti-blowout structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a structural schematic diagram of the present utility model;

[0014] Figure 2 is a schematic diagram of the pressing plate fixing screw of the present utility model.

[0015] In the figure: 1. Butterfly valve body; 2. Bush pressing plate; 3. Pressing plate fixing screw; 4. O-ring; 5. Quick-release bush; 6. Butterfly valve body; 7. Quick-release hole; 8. Bush shoulder; 9. Shoulder; 10. Tightening rod; 11. Annular groove; 12. Fixed ring; 13. Annular pressing piece; 14. Extrusion block; 15. Annular rubber sheet; 16. Spring; 17. Tightening cylinder; 18. Tightening nut; 19. Tightening groove; 20. Limit post; 21. Spiral groove. Detailed implementation manner

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0017] Please refer to Figure 1-2 , the present invention provides a technical solution:

[0018] In this technical solution, a replaceable shaft seal structure for a butterfly valve online includes a butterfly valve body 6. A valve shaft 1 is assembled inside the butterfly valve body 6. A shoulder 9 is provided between the butterfly valve body 6 and the valve shaft 1. An upper end of the shoulder 9 is provided with a bush shoulder 8. A quick-release hole 7 is assembled at an upper end of the bush shoulder 8. A bush pressing plate 2 is assembled outside the valve shaft 1. A pressing plate fixing screw 3 is assembled between the bush pressing plate 2 and the butterfly valve body 6. An O-ring 4 is sleeved outside the valve shaft 1. A quick-release bush 5 is sleeved outside the valve shaft 1. The butterfly valve body 6 is provided with a fixing hole at the position of the pressing plate fixing screw 3, and a tightening cylinder 17 is installed in the fixing hole. A tightening rod 10 is installed in the tightening cylinder 17. A tightening groove 19 is opened at a bottom end of the pressing plate fixing screw 3. The pressing plate fixing screw 3 is sleeved outside the tightening rod 10 through the tightening groove 19. The tightening cylinder 17 is fixed in the fixing hole, and the tightening rod 10 is installed in the tightening cylinder 17 by means of threaded connection.

[0019] Three limit posts 20 are assembled on an outer wall of the tightening cylinder 17. The three limit posts 20 are distributed in a triangular shape. A spiral groove 21 matching with an external thread of the pressing plate fixing screw 3 is opened on an outer wall of the limit post 20. A tightening nut 18 is sleeved outside the pressing plate fixing screw 3.

[0020] An annular groove 11 is opened at a bottom end of the tightening nut 18. A top end of the limit post 20 is arranged in the annular groove 11.

[0021] A fixed ring 12 is fixedly installed at an upper end outside the pressing plate fixing screw 3. An annular pressing piece 13, a spring 16 and an annular rubber sheet 15 are sleeved on a circumferential surface of the pressing plate fixing screw 3.

[0022] An extrusion block 14 is fixedly mounted on the lower edge of the annular pressing sheet 13 .

[0023] The outer wall of the fastening rod 10 is provided with an external thread, and the inner wall of the fastening cylinder 17 is provided with an internal thread matching the external thread.

[0024] The outer diameter of the sleeve shoulder 8 is greater than the inner diameter of the quick-release sleeve 5 .

[0025] Working process and principle: The quick-release sleeve is provided with three inner and outer O-ring grooves, and the quick-release sleeve is provided with a quick-release hole. The three O-rings are installed in the O-ring of the quick-release sleeve, and the quick-release sleeve is installed between the valve shaft and the valve body. The outer diameter of the valve shaft shoulder is larger than the inner diameter of the quick-release sleeve, so that the movement of the valve shaft along the axis to the outside of the valve body is limited by the position of the quick-release sleeve. The sleeve pressure plate is locked on the valve body by the pressure plate fixing screws. The diameter of the center hole of the sleeve pressure plate is larger than the inner diameter of the quick-release sleeve shoulder and smaller than the outer diameter of the quick-release sleeve shoulder, which can limit the movement of the quick-release sleeve along the axis to the outside of the valve body. The purpose of "anti-blowout" of the valve shaft is achieved, that is, the valve shaft will not move along the axis to the outside of the valve body to detach from the valve body shaft hole due to the force of the inner cavity. When replacing the seal, unscrew the fixing screws of the pressure plate, take out the shaft sleeve pressure plate, use a hook-type tool to hook the quick-release hole, pull it toward the outside of the valve body along the axis, pull out the shaft sleeve to replace the O-ring, and then reinstall the shaft sleeve, pressure plate, and screws in sequence.

[0026] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0027] Although the present invention has been described above with reference to the embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed in the present invention may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An online replaceable shaft seal structure for a butterfly valve, comprising a butterfly valve body (6), characterized in that: The butterfly valve body (6) is internally mounted with a valve shaft (1), a shaft shoulder (9) is provided between the butterfly valve body (6) and the valve shaft (1), a shaft sleeve shaft shoulder (8) is provided at the upper end of the shaft shoulder (9), a quick-release hole (7) is provided at the upper end of the shaft sleeve shaft shoulder (8), a shaft sleeve pressure plate (2) is externally mounted on the valve shaft (1), a pressure plate fixing screw (3) is provided between the shaft sleeve pressure plate (2) and the butterfly valve body (6), and the outer sleeve of the valve shaft (1) is provided with a shaft sleeve pressure plate (2). An O-ring (4) is installed, the outside of the valve shaft (1) is sleeved with a quick-release sleeve (5), the butterfly valve body (6) is provided with a fixing hole at the pressure plate fixing screw (3), and a fastening cylinder (17) is installed in the fixing hole, a fastening rod (10) is installed in the fastening cylinder (17), and a fastening groove (19) is opened at the bottom end of the pressure plate fixing screw (3), and the pressure plate fixing screw (3) is sleeved on the outside of the fastening rod (10) through the fastening groove (19).

2. The online replaceable shaft seal structure for a butterfly valve according to claim 1 is characterized in that: The outer wall of the fastening cylinder (17) is equipped with three limit columns (20), which are distributed in a triangular shape. The outer wall of the limit column (20) is provided with a spiral groove (21) that matches the external thread of the pressure plate fixing screw (3), and the outer part of the pressure plate fixing screw (3) is sleeved with a fastening nut (18).

3. The online replaceable shaft seal structure for a butterfly valve according to claim 2 is characterized in that: An annular groove (11) is formed at the bottom end of the fastening nut (18), and the top end of the limiting column (20) is arranged in the annular groove (11).

4. The online replaceable shaft seal structure for a butterfly valve according to claim 2, characterized in that: A fixing ring (12) is fixedly mounted on the outer upper end of the pressure plate fixing screw (3), and an annular pressure sheet (13), a spring (16) and an annular rubber sheet (15) are sleeved on the circumferential surface of the pressure plate fixing screw (3).

5. The online replaceable shaft seal structure for a butterfly valve according to claim 4 is characterized in that: An extrusion block (14) is fixedly mounted on the lower edge of the annular pressing sheet (13).

6. The online replaceable shaft seal structure for a butterfly valve according to claim 1, characterized in that: The outer wall of the fastening rod (10) is provided with an external thread, and the inner wall of the fastening cylinder (17) is provided with an internal thread matching the external thread.

7. The online replaceable shaft seal structure for a butterfly valve according to claim 1, characterized in that: The outer diameter of the shaft sleeve shoulder (8) is greater than the inner diameter of the quick-release shaft sleeve (5).

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