A sealing device applied to stable operation of a polyvinyl chloride dispersion system

Abstract

The utility model provides a kind of sealing device applied to the stable operation of polyvinyl chloride dispersion system, adopt containerized design to realize quick dismounting maintenance, through the tandem structure of driving ring-main static ring-vice driving ring-vice static ring, significantly improve the sealing reliability, main sealing end surface is accurately balanced according to seal hydraulic pressure, vice sealing can bear higher pressure;Adopt double-sealing structure with pressure to ensure that sealing fluid leaks inside first when leaking;And by fixing driving ring directly on sealing shaft sleeve and using anti-rotation pin and O-ring double fixation, effectively prevent the axial displacement caused by medium pressure fluctuation, significantly improve the stability of main sealing end surface;At the same time, transmission key is used to connect spring seat and sealing shaft sleeve, solve the problem of spring seat displacement caused by traditional locking screw loose, ensure the long-term reliable operation of vice sealing;These improvements greatly improve the overall reliability of sealing, especially suitable for harsh working conditions such as high pressure, vibration and corrosive medium.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical seal technology, specifically relating to a sealing device for the stable operation of a polyvinyl chloride dispersion system. Background Technology

[0002] Most mechanical seals currently used are split-type seals, requiring on-site assembly by technicians. Split-type mechanical seals have extremely high requirements for pump installation dimensions. Due to accumulated errors in the axial dimensions of many pumps, the installation height of the seal spring deviates significantly from the theoretical value, leading to situations where the spring force is too high or too low. Excessive spring force increases the spring specific pressure, accelerating wear on the dynamic and static annular surfaces, and may even cause cracking. Insufficient spring force results in insufficient specific pressure, failing to provide a seal.

[0003] Furthermore, the installation of split-type mechanical seals is cumbersome, and workers are prone to damaging the dynamic and static rings or chipping the O-rings during installation, causing inconvenience to the work. The commonly used two sets of mechanical seals are used back-to-back. When the external sealing fluid pressure is generally higher than 0.4 MPa, the outer mechanical seal is under back pressure, which will lead to serious leakage.

[0004] Therefore, there is an urgent need to design a simple and reliable mechanical seal device. Utility Model Content

[0005] This invention provides a sealing device for the stable operation of a polyvinyl chloride dispersion system, which solves the problems of complex installation and easy leakage of mechanical seals in the prior art.

[0006] This utility model provides a sealing device for stable operation of a polyvinyl chloride dispersion system, including an end cover, a gland, a drive shaft, a pump shaft sleeve, a sealing shaft sleeve, a driving ring, a driving O-ring, a driving anti-rotation pin, a main stationary ring, a main stationary O-ring, a main push ring, a main stationary anti-rotation pin, a spring seat, a drive key, a secondary driving ring, a secondary driving O-ring, a secondary stationary ring, and a secondary stationary O-ring. The drive shaft passes through the end cover and gland, with the end cover located on the side closest to the medium and axially fixedly assembled with the gland. The pump shaft sleeve and the sealing shaft sleeve are disposed inside the end cover and gland. The pump shaft sleeve is fitted onto the outside of the drive shaft and rotates synchronously with it. The sealing shaft sleeve is fitted onto the outside of the pump shaft sleeve and rotates synchronously with it. The driving ring is fixedly fitted onto the side of the sealing shaft sleeve closest to the medium, and is press-fitted with the sealing shaft sleeve by the driving O-ring. The driving ring is connected to the sealing shaft sleeve by the driving anti-rotation pin. The bushing is circumferentially fixed and rotates synchronously with the sealing bushing. The main stationary ring is located at the end of the active ring furthest from the medium and fits tightly with the active ring to form the main sealing end face. The main stationary ring is fixedly connected to the end cover via an interference fit with the main stationary O-ring. A main push ring is located inside the end cover, and a main stationary anti-rotation pin is located on the main push ring. The main stationary ring is circumferentially fixedly connected to the end cover via the main stationary anti-rotation pin. A spring seat is fitted on the side of the sealing bushing closest to the atmosphere, and the spring seat is fixedly connected to the sealing bushing circumferentially via a transmission key. The auxiliary moving ring is fitted on the sealing bushing and fixedly connected to the spring seat. The auxiliary moving ring fits tightly with the sealing bushing via an auxiliary moving O-ring and rotates synchronously with the sealing bushing. The auxiliary stationary ring is located at the end of the auxiliary moving ring closest to the atmosphere and fits tightly with the auxiliary moving ring to form the auxiliary sealing end face. The auxiliary stationary ring fits tightly with the gland via an interference fit with the gland, and is fixedly connected to the gland.

[0007] Compared with existing technologies, the advantages of this utility model are as follows: The sealing device provided by this utility model for stable operation of polyvinyl chloride dispersion systems adopts a modular design for quick disassembly and maintenance. The series structure of active ring-main stationary ring-secondary active ring-secondary stationary ring significantly improves sealing reliability. The main sealing end face is precisely balanced according to the sealing fluid pressure, and the secondary seal can withstand higher pressures. The pressurized double-seal structure (system pressure 0.1-0.2 MPa higher than the medium) ensures that the sealing fluid leaks internally first in case of leakage, completely eliminating the leakage of medium from the pump. Furthermore, by directly fixing the active ring to the sealing bushing and using anti-rotation pins and O-rings for double fixation, axial displacement caused by medium pressure fluctuations is effectively prevented, significantly improving the stability of the main sealing end face. Simultaneously, the use of a transmission key to connect the spring seat and the sealing bushing solves the problem of spring seat displacement caused by the easy loosening of traditional set screws, ensuring long-term reliable operation of the secondary seal. In addition, the design of directly fixing the main stationary ring to the gland simplifies the structure and enhances vibration resistance. These improvements significantly enhance the overall reliability of the seal, making it particularly suitable for harsh conditions such as high pressure, vibration, and corrosive media.

[0008] Furthermore, an anti-extrusion O-ring is provided between the drive ring and the sealing bushing to limit the axial displacement of the drive ring.

[0009] Furthermore, the pump shaft sleeve is circumferentially fixedly connected to the drive shaft via a flat key; and / or, the sealing shaft sleeve is circumferentially fixedly connected to the pump shaft sleeve via a shaft sleeve O-ring, a locating ring, and a set screw.

[0010] Furthermore, a cooling water inlet is provided on one side of the end cap, and a cooling water outlet is provided on the other side; the cooling water inlet is connected to the cooling water outlet through a sealing cavity, and the cooling lubricant enters the sealing cavity from the cooling water inlet to clean, lubricate and cool the auxiliary moving ring, auxiliary stationary ring, active ring and main stationary ring, and then flows out from the cooling water outlet.

[0011] Furthermore, the end cover is provided with an internal flushing port, which is used to introduce the pump medium to flush the active ring and the main stationary ring before it flows back into the pump.

[0012] Furthermore, an O-ring is provided between the end cap and the gland, and the end cap and the gland are fixedly connected by a cylindrical head socket screw; an end cap O-ring is also provided on the side of the end cap closest to the medium.

[0013] Furthermore, a sealing sleeve O-ring is provided between the sealing sleeve and the pump sleeve; and / or, a pump sleeve O-ring is provided between the pump sleeve and the drive shaft.

[0014] Furthermore, a main spring is connected to the end of the main push ring away from the main stationary ring, and the main spring is used to provide a compensating force to the main sealing end face; and / or, a secondary spring is connected to one end of the spring seat, and a secondary push ring is connected to the other end of the secondary spring, and the other side of the secondary push ring is connected to the secondary moving ring; the secondary spring is used to provide a compensating force to the secondary sealing end face.

[0015] Furthermore, a positioning plate is provided on the side of the gland closest to the atmosphere, and the positioning plate is fixedly connected to the gland by hexagonal head bolts.

[0016] Furthermore, the gland and end cap are fixedly connected to the pump chamber via screw holes. Attached Figure Description

[0017] Figure 1 A schematic diagram of the sealing device provided by this utility model for the stable operation of a polyvinyl chloride dispersion system.

[0018] Explanation of reference numerals in the attached figures:

[0019] 1. Driving ring; 2. Driving O-ring; 3. Main stationary ring; 4. Main stationary O-ring; 5. Main spring; 6. Driving anti-rotation pin; 7. Anti-extrusion O-ring; 8. Main push ring; 9. Main stationary anti-rotation pin; 10. Transmission key; 11. Auxiliary driving O-ring; 12. Auxiliary driving ring; 13. Auxiliary stationary ring; 14. Auxiliary stationary O-ring; 15. Spring seat; 16. Auxiliary spring; 17. Auxiliary push ring; 18. Sealing bushing; 19. Sealing bushing O-ring; 20. Pump bushing; 21. Pump bushing O-ring; 22. Flat key; 23. End cover; 24. End cover O-ring; 25. Pressure cap; 26. Pressure cap O-ring; 27. Cylindrical head socket head cap screw; 28. Positioning plate; 29. ​​Hex head bolt; 30. Positioning ring; 31. Set screw. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] Please see Figure 1 This utility model provides a sealing device for stable operation of a polyvinyl chloride dispersion system, including an end cap 23, a pressure cap 25, a drive shaft, a pump shaft sleeve 20, a sealing shaft sleeve 18, a driving ring 1, a driving O-ring 2, a driving anti-rotation pin 6, a main stationary ring 3, a main stationary O-ring 4, a main push ring 8, a main stationary anti-rotation pin 9, a spring seat 15, a transmission key 10, a secondary driving ring 12, a secondary driving O-ring 11, a secondary stationary ring 13, and a secondary stationary O-ring 14;

[0022] A drive shaft passes through the end cover 23 and the gland 25. The end cover 23 is located on the side closer to the medium and is axially fixedly assembled with the gland 25. The pump shaft sleeve 20 and the sealing shaft sleeve 18 are located inside the end cover 23 and the gland 25. The pump shaft sleeve 20 is fitted on the outside of the drive shaft and rotates synchronously with the drive shaft. The sealing shaft sleeve 18 is fitted on the outside of the pump shaft sleeve 20 and rotates synchronously with the pump shaft sleeve 20. The active ring 1 is fixedly fitted on the side of the sealing shaft sleeve 18 closer to the medium and is press-fitted with the sealing shaft sleeve 18 through the active O-ring 2. The active ring 1 is circumferentially fixedly connected to the sealing shaft sleeve 18 through the active anti-rotation pin 6 and rotates synchronously with the sealing shaft sleeve 18. The main stationary ring 3 is located at the end of the active ring 1 away from the medium and is tightly fitted with the active ring 1 to form the main sealing end face. The main stationary ring 3 is connected to the main stationary O-ring 4 through the main stationary O-ring 4. The end cap 23 is interference-fitted and fixedly connected to the end cap 23. A main push ring 8 is provided on the inner side of the end cap 23, and a main static anti-rotation pin 9 is provided on the main push ring 8. The main static ring 3 is circumferentially fixedly connected to the end cap 23 through the main static anti-rotation pin 9. A spring seat 15 is fitted on the side of the sealing bushing 18 closest to the atmosphere. The spring seat 15 is circumferentially fixedly connected to the sealing bushing 18 through the transmission key 10. The auxiliary moving ring 12 is fitted on the sealing bushing 18 and fixedly connected to the spring seat 15. The auxiliary moving ring 12 is interference-fitted to the sealing bushing 18 through the auxiliary moving O-ring 11 and rotates synchronously with the sealing bushing 18. The auxiliary static ring 13 is set at the end of the auxiliary moving ring 12 closest to the atmosphere and is tightly fitted with the auxiliary moving ring 12 to form a secondary sealing end face. The auxiliary static ring 13 is interference-fitted to the pressure cap 25 through the auxiliary static O-ring 14 and is fixedly connected to the pressure cap 25.

[0023] This utility model provides a sealing device for stable operation of a polyvinyl chloride dispersion system. It employs a modular design for quick disassembly and maintenance. The series structure of active ring 1, main stationary ring 3, auxiliary active ring 12, and auxiliary stationary ring 13 significantly improves sealing reliability. The main sealing end face is precisely balanced according to the sealing fluid pressure, and the auxiliary seal can withstand higher pressures. The pressurized double-seal structure (system pressure 0.1–0.2 MPa higher than the medium) ensures that the sealing fluid leaks internally first in case of leakage, completely preventing the medium from overflowing from the pump. Furthermore, by directly fixing the active ring 1 to the sealing sleeve 18 and using both anti-rotation pins and O-rings for double fixation, axial displacement caused by medium pressure fluctuations is effectively prevented, significantly improving the stability of the main sealing end face. Simultaneously, the use of a transmission key 10 to connect the spring seat 15 to the sealing sleeve 18 solves the problem of spring seat 15 displacement caused by the easy loosening of the traditional set screw 31, ensuring long-term reliable operation of the auxiliary seal. In addition, the design of directly fixing the main stationary ring 3 to the pressure cap 25 simplifies the structure and enhances vibration resistance. These improvements significantly enhance the overall reliability of the seal, making it particularly suitable for harsh conditions such as high pressure, vibration, and corrosive media.

[0024] Furthermore, an anti-extrusion O-ring 7 is provided between the drive ring 1 and the sealing bushing 18 to limit the axial displacement of the drive ring 1. By adding an anti-extrusion O-ring to the inside of the drive ring 1, it is possible to further prevent the mechanical seal cooling water from squeezing out the drive ring 1 due to excessive pressure fluctuations, further reduce the compression between the drive ring 1 and the main stationary ring 3, and reduce the wear and damage of the drive ring 1 and the main stationary ring 3.

[0025] In one specific embodiment, the pump shaft sleeve 20 is circumferentially fixedly connected to the drive shaft via a flat key 22; the sealing shaft sleeve 18 is circumferentially fixedly connected to the pump shaft sleeve 20 via a shaft sleeve O-ring, a positioning ring 30, and a set screw 31.

[0026] The pump shaft sleeve 20 is reliably circumferentially fixed to the drive shaft via a flat key 22, ensuring the stability and accuracy of torque transmission. Meanwhile, the sealing shaft sleeve 18 is connected to the pump shaft sleeve 20 using a triple-fixing method: a shaft sleeve O-ring, a locating ring 30, and a set screw 31. The shaft sleeve O-ring provides initial interference fit and vibration damping, the locating ring 30 ensures axial assembly accuracy, and the set screw 31 provides final locking. This combined connection structure ensures the synchronous rotation accuracy of the sealing shaft sleeve 18 and the pump shaft sleeve 20, and effectively prevents relative displacement caused by vibration. Compared to the traditional single set screw 31 fixing method, it has higher reliability and longer service life, and is particularly suitable for harsh operating conditions with high speed and strong vibration.

[0027] In one specific embodiment, the end cap 23 has a cooling water inlet on one side and a cooling water outlet on the other side; the cooling water inlet is connected to the cooling water outlet through a sealing cavity, and the cooling lubricant enters the sealing cavity from the cooling water inlet to clean, lubricate and cool the auxiliary moving ring 12, the auxiliary stationary ring 13, the active ring 1 and the main stationary ring 3, and then flows out from the cooling water outlet.

[0028] The end cap 23 is provided with an internal flushing port, which is used to introduce the pump medium to flush the active ring 1 and the main stationary ring 3 and then return it to the pump.

[0029] First, the flushing flow can effectively remove the heat generated by friction on the sealing end face, preventing overheating damage. Second, the flowing medium can promptly remove wear particles and crystals from the end face, preventing the medium from sticking to the moving and stationary rings. Finally, the internal pump medium self-circulation flushing method not only ensures the flushing effect but also avoids the complex structure and medium waste problems caused by external flushing systems, achieving energy-saving, environmentally friendly, reliable and stable sealing cooling and cleaning functions.

[0030] Specifically, a pressure cap O-ring 26 is provided between the end cap 23 and the pressure cap 25, and the end cap 23 and the pressure cap 25 are fixedly connected by a cylindrical head hexagonal screw 27; an end cap O-ring 14 is also provided on the side of the end cap 23 closest to the medium; a sealing sleeve O-ring 19 is provided between the sealing sleeve 18 and the pump sleeve 20; a pump sleeve O-ring 21 is provided between the pump sleeve 20 and the drive shaft; a main spring 5 is connected to the end of the main thrust ring 8 away from the main stationary ring 3, and the main spring 5 is used to provide compensation force to the main sealing end face; a secondary spring 16 is connected to one end of the spring seat 15, and a secondary thrust ring 17 is connected to the other end of the secondary spring 16, and the other side of the secondary thrust ring 17 is connected to the secondary moving ring 12; the secondary spring 16 is used to provide compensation force to the secondary sealing end face. A positioning plate 28 is provided on the side of the pressure cover 25 that is close to the atmosphere. The positioning plate 28 is fixedly connected to the pressure cover 25 by hexagonal head bolts 29. The pressure cover 25 and the end cover 23 are fixedly connected to the pump cavity through screw holes to realize a cartridge mechanical seal.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, they should be considered to be within the protection scope of this utility model.

Claims

1. A sealing device applied to the stable operation of a polyvinyl chloride dispersion system, characterized in that, Includes end caps, glands, drive shafts, pump shaft sleeves, sealing shaft sleeves, drive rings, drive O-rings, drive anti-rotation pins, main stationary rings, main stationary O-rings, main thrust rings, main stationary anti-rotation pins, spring seats, drive keys, auxiliary drive rings, auxiliary drive O-rings, auxiliary stationary rings, and auxiliary stationary O-rings; A drive shaft runs through the end cover and gland. The end cover is located on the side closest to the medium and is fixedly assembled with the gland along the axial direction. The pump shaft sleeve and sealing shaft sleeve are located inside the end cover and gland. The pump shaft sleeve is fitted on the outside of the drive shaft and rotates synchronously with the drive shaft; the sealing shaft sleeve is fitted on the outside of the pump shaft sleeve and rotates synchronously with the pump shaft sleeve. The active ring is fixedly sleeved on the side of the sealing bushing closest to the medium and is interference-fitted with the sealing bushing; The main stationary ring is located at the end of the active ring furthest from the medium, and fits tightly with the active ring to form the main sealing end face; the main stationary ring is fixedly connected to the end cover with an interference fit. A spring seat is fitted on the side of the sealing bushing closest to the atmosphere, and the spring seat is circumferentially fixedly connected to the sealing bushing via a transmission key; The auxiliary moving ring is sleeved on the sealing shaft sleeve and fixedly connected to the spring seat. The auxiliary moving ring is interference-fitted with the sealing shaft sleeve through the auxiliary moving O-ring and rotates synchronously with the sealing shaft sleeve. The secondary stationary ring is located at the end of the secondary moving ring closest to the atmosphere, and fits tightly with the secondary moving ring to form a secondary sealing end face; the secondary stationary ring is fixedly connected to the gland through an interference fit with the secondary stationary O-ring.

2. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, characterized in that, It also includes an active O-ring and an active anti-rotation pin. The active ring is interference-fitted with the sealing sleeve via the active O-ring and circumferentially fixed to the sealing sleeve via the active anti-rotation pin, rotating synchronously with the sealing sleeve; and / or, It also includes a main stationary O-ring, which is interference-fitted with the end cap; and / or, The inner side of the end cap is also provided with a main push ring, on which a main static anti-rotation pin is provided. The main static ring is circumferentially fixedly connected to the end cap through the main static anti-rotation pin; and / or, An anti-extrusion O-ring is provided between the drive ring and the sealing bushing to limit the axial displacement of the drive ring.

3. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, characterized in that, The pump shaft sleeve is circumferentially fixed to the drive shaft via a flat key; and / or, The sealing bushing is circumferentially fixed to the pump bushing via a bushing O-ring, a locating ring, and a set screw.

4. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein The end cap has a cooling water inlet on one side and a cooling water outlet on the other side. The cooling water inlet is connected to the cooling water outlet through a sealing cavity. The cooling lubricant enters the sealing cavity from the cooling water inlet to clean, lubricate, and cool the auxiliary moving ring, auxiliary stationary ring, driving ring, and main stationary ring, and then flows out from the cooling water outlet.

5. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein The end cover is provided with an internal flushing port, which is used to introduce the medium into the pump to flush the active ring and the main stationary ring before it flows back into the pump.

6. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein An O-ring is provided between the end cap and the gland, and the end cap and the gland are fixedly connected by a cylindrical head socket screw; an end cap O-ring is also provided on the side of the end cap closer to the medium.

7. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein A sealing O-ring is provided between the sealing bushing and the pump bushing; and / or, An O-ring is provided between the pump shaft sleeve and the drive shaft.

8. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein A main spring is connected to the end of the main thrust ring furthest from the main stationary ring. The main spring provides a compensating force to the main sealing end face; and / or, A secondary spring is connected to one end of the spring seat, and a secondary push ring is connected to the other end of the secondary spring. The other side of the secondary push ring is connected to the secondary moving ring. The secondary spring is used to provide compensation force to the secondary sealing end face.

9. The sealing device for stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein The side of the gland close to the atmosphere is provided with a positioning plate, and the positioning plate is fixedly connected with the gland through a hexagonal head bolt.

10. The seal for use in a stable operation of a polyvinyl chloride dispersion system according to claim 1, wherein The gland and the end cover are fixedly connected with the pump cavity through screw holes.

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