A set type mechanical seal structure applied to a water pump

Abstract

The application discloses a kind of application for water pump's packing type mechanical seal structure, including shaft sleeve gland, inner dynamic ring, outer dynamic ring, static ring, gland, power ring and elastic element etc.parts.Shift sleeve is sleeved in the outer circumferential surface of water pump shaft, gland is sleeved in the outer circumferential surface of shaft sleeve, inner dynamic ring is fixed with shaft sleeve, outer dynamic ring and static ring are sleeved in the outer circumferential surface of inner dynamic ring and form sealed end face adhesion, sealing ring is arranged between each component.Power ring is drivingly connected with shaft sleeve, elastic element forces outer dynamic ring and static ring to provide pre-tightening force, and flushing mechanism is also provided.The application achieves the effect of improving mechanical seal performance, guaranteeing sealing reliability and stability, and flushing the sealing end face through flushing mechanism, prolonging the service life of sealing structure.

Description

Technical Field

[0001] This application relates to the field of mechanical seals, and more particularly to a cartridge mechanical seal structure for use in water pumps. Background Technology

[0002] In the field of water pumps, shaft seals play a crucial role in ensuring the normal operation of water pumps and preventing media leakage. With the continuous development of industry, the application scenarios of water pumps are becoming increasingly widespread, and the performance requirements for shaft seals are also becoming more stringent. Highly efficient and reliable shaft seals can improve the working efficiency of water pumps, reduce energy consumption, lower maintenance costs, and thus enhance the stability and economy of the entire industrial production system. A good shaft seal can also effectively prevent the leakage of harmful media, protecting the environment and personnel safety.

[0003] Prior to this technical solution, the industry commonly used packing seals as a traditional method to solve pump shaft sealing problems. Packing seals primarily rely on multiple wrappings of rope-like sealing material around the pump shaft to achieve a sealing effect. This method is common in some simple pump applications, is relatively easy to operate, and has a relatively low cost. Other sealing methods may use ordinary rubber ring seals, but the sealing effect and reliability of this method are relatively limited, making it difficult to meet the requirements of pumps with high sealing demands. Additionally, some pumps may use single-end mechanical seals, achieving sealing through the contact of the dynamic and static rings; however, this sealing method also has limitations in stability and durability under some complex operating conditions.

[0004] However, existing packing seals have many drawbacks. Their sealing materials wear out quickly, leading to frequent leaks. Furthermore, the direct friction between the packing seal and the rotating shaft not only causes journal wear but also generates significant heat, affecting the normal operation of the equipment. In addition, packing seals have a short service life, requiring frequent adjustments and replacements, which significantly increases maintenance costs and reduces overall reliability. Summary of the Invention

[0005] In order to extend the service life of the sealing structure, this application provides a cartridge mechanical seal structure for use in water pumps.

[0006] The technical solution provided in this application for a cartridge-type mechanical seal structure applied to a water pump is as follows: A cartridge mechanical seal structure for a water pump includes a shaft sleeve gland, an inner rotating ring, an outer rotating ring, a stationary ring, a gland, a power ring, and an elastic element. The shaft sleeve is fitted onto the outer circumference of the water pump shaft. The gland is fitted onto the outer circumference of the shaft sleeve. The inner rotating ring is fitted onto the outer circumference of the shaft sleeve and fixedly connected to it. The outer rotating ring and the stationary ring are both fitted onto the outer circumference of the inner rotating ring and distributed along the axial direction of the shaft sleeve. The outer rotating ring and the stationary ring form a sealing end face that fits together. The outer rotating ring and the inner rotating ring are fixedly connected. The stationary ring is fixed to the anti-rotation pin of the gland. A first sealing ring is provided between the inner rotating ring and the shaft sleeve, and a second sealing ring is provided between the outer rotating ring and the inner rotating ring. The elastic element is used to force the outer rotating ring and the stationary ring to abut against each other, providing elastic preload to the sealing end face.

[0007] By adopting the above technical solution, the mechanical seal is designed as a modular unit, ensuring the relative positional accuracy of each component, simplifying the installation process, and reducing the risk of early failure due to improper installation. The inner moving ring is fixedly connected to the shaft sleeve, and the outer moving ring is fixedly connected to the inner moving ring, while the stationary ring is fixed to the gland by an anti-rotation pin, forming a clear power transmission path and sealing interface. The continuous clamping force provided by the elastic element ensures a tight fit between the sealing end faces of the outer moving ring and the stationary ring, maintaining a stable sealing pressure even when there is slight shaft movement. The multiple sealing rings (first and second sealing rings) form multiple lines of defense for sealing. The second sealing ring prevents the medium from leaking from the inside of the mechanical seal cavity, and the first sealing ring prevents the medium from leaking from the inside of the shaft sleeve, significantly improving the overall reliability of the sealing structure and reducing the risk of leakage.

[0008] Preferably, the power ring and the bushing are connected by a fastener, which passes through the power ring and is connected to the outer wall of the bushing.

[0009] By adopting the above technical solutions, the fasteners provide reliable power transmission, ensuring that the power ring can effectively drive the bushing and the rotating ring assembly to rotate synchronously, preventing wear or seal failure caused by relative sliding. Some cartridge seals use anti-loosening screws instead of ordinary set screws, which can effectively prevent the connection from loosening or falling off due to vibration, improving the stability of the structure under vibration conditions.

[0010] Preferably, the elastic element includes a mounting ring seat and a spring. The mounting ring seat is fixedly sleeved on the outer circumferential surface of the inner moving ring. The inner side of the mounting ring seat is provided with a receiving groove for accommodating the spring. One end of the spring is connected to the receiving groove, and the other end of the spring presses against the outer moving ring in the direction of the stationary ring, forcing the outer moving ring and the stationary ring to press against each other, thereby providing elastic preload to the sealing end face.

[0011] By adopting the above technical solution, the mounting ring seat provides stable support and positioning for the spring, and the receiving groove structure ensures that the spring force is evenly distributed, guaranteeing that the elastic force is smoothly applied to the outer moving ring. This design helps maintain a constant specific pressure at the sealing end face, avoiding unstable sealing performance caused by fluctuations in elastic force. Integrating elastic compensation elements such as springs into the module improves the overall integrity and reliability of the sealing structure.

[0012] Preferably, a pressure ring is provided on the outer side of the mounting ring seat, the pressure ring extends to the outer side of the outer moving ring, and the pressure ring applies a clamping force to the outer moving ring in a manner that faces the inner moving ring, so that the outer moving ring and the inner moving ring abut against each other.

[0013] By adopting the above technical solution, the pressure ring extends to the outside of the outer moving ring and applies a clamping force, making the outer moving ring and the inner moving ring fit more tightly. This not only enhances the connection stability between the inner and outer moving rings, but may also help improve the sealing effect of the second sealing ring, while also providing a certain restraint on any slight axial or radial displacement that may occur in the outer moving ring.

[0014] Preferably, the outer moving ring has an annular groove for accommodating the second sealing ring on the side near the mounting ring seat, and the spring applies a clamping force to both the outer moving ring and the second sealing ring at the end facing the stationary ring.

[0015] By adopting the above technical solution, the spring's clamping force not only acts on the sealing end face but also indirectly enhances the sealing effect of the second sealing ring. This design ensures that the second sealing ring maintains a good fit during long-term operation, and effectively prevents media leakage from the mating surface between the outer and inner moving rings, especially during fluctuations in operating conditions or equipment vibration.

[0016] Preferably, it also includes a flushing mechanism, the flushing structure including a flushing water inlet and a distribution channel disposed at the pressure cap, the distribution channel being disposed around the sealing end face and communicating with the flushing water inlet.

[0017] By adopting the above technical solutions, the flushing mechanism can effectively cool the sealing end face, remove the heat generated by friction, and prevent the sealing end face from deforming and failing due to overheating. This is crucial for water pumps operating at high temperatures or high speeds. Simultaneously, the flushing fluid can also remove tiny particles that may intrude into the sealing area, reducing abrasive wear and significantly extending the service life of the dynamic and stationary rings. Some high-efficiency cooling designs also employ a series double-end face seal combined with cooling channels, further improving sealing performance and service life under harsh operating conditions.

[0018] Preferably, a third sealing ring is provided between the gland and the stationary ring.

[0019] Preferably, a fourth sealing ring is provided on the contact surface between the gland and the water pump. Preferably, a fifth sealing ring is provided between the bushing and the outer circumferential surface of the water pump shaft.

[0020] By employing the above technical solutions, these seals together constitute a complete static sealing system, effectively blocking the leakage path of the medium along the non-moving mating surfaces. The combined use of multiple O-rings ensures the sealing reliability of the entire sealing system at the dynamic and static interfaces, minimizing leakage points.

[0021] In summary, this application includes at least one of the following beneficial technical effects: 1. The mechanical seal is designed as a modular unit, which ensures the relative positional accuracy of each component, simplifies the installation process, and reduces the risk of early failure due to improper installation; the continuous clamping force provided by the elastic element ensures a tight fit between the outer dynamic ring and the stationary ring sealing end faces, maintaining a stable sealing pressure even when there is slight shaft movement; the multiple sealing rings form multiple sealing defenses, significantly improving the overall reliability of the sealing structure and reducing the risk of leakage. 2. The flushing mechanism can effectively cool the sealing end face, remove the heat generated by friction, and prevent the sealing end face from deforming and failing due to overheating; it can also flush away tiny particles that may invade the sealing area, reduce abrasive wear, and significantly extend the service life of the dynamic ring and stationary ring. 3. The mounting ring seat provides stable support and positioning for the spring. The spring continuously applies a clamping force to the outer moving ring, ensuring a tight fit between the outer moving ring and the stationary ring sealing end face. Even if there is slight shaft movement, a stable sealing pressure can be maintained. Integrating elastic compensation elements such as springs into the module improves the overall integrity and reliability of the sealing structure. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a cartridge mechanical seal structure applied to a water pump according to an embodiment of this application.

[0023] Explanation of reference numerals in the attached drawings: 1. Fifth sealing ring; 2. First sealing ring; 3. Second sealing ring; 4. Fourth sealing ring; 5. Third sealing ring; 6. Outer moving ring; 7. Stationary ring; 8. Spring; 9. Bushing; 10. Inner moving ring; 11. Mounting ring seat; 12. Pressure cap; 13. Positioning block; 14. Power ring; 15. Concave end set screw; 16. Cylindrical head set screw; D. Flushing structure. Detailed Implementation

[0024] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.

[0025] This application discloses a cartridge mechanical seal structure for use in water pumps, referring to... Figure 1The system includes a bushing 9, an inner moving ring 10, an outer moving ring 6, a stationary ring 7, a gland 12, a power ring 14, and an elastic element. The bushing 9 is fitted onto the outer circumference of the pump shaft, the gland 12 is fitted onto the outer circumference of the bushing 9, the inner moving ring 10 is fitted onto the outer circumference of the bushing 9 and fixedly connected to the bushing 9, the outer moving ring 6 and the stationary ring 7 are both fitted onto the outer circumference of the inner moving ring 10 and distributed along the axial direction of the bushing 9, the outer moving ring 6 and the stationary ring 7 form a sealing end face fit together, the outer moving ring 6 and the inner moving ring 10 are fixedly connected, and the stationary ring 7 is fixed to the anti-rotation pin of the gland 12. A first sealing ring 2 is provided between the inner moving ring 10 and the bushing 9, and a second sealing ring 3 is provided between the outer moving ring 6 and the inner moving ring 10. The elastic element is used to force the outer moving ring 6 and the stationary ring 7 to press against each other, providing elastic pre-tightening force to the sealing end face, thereby improving the overall reliability of the sealing structure and reducing the risk of leakage. This is because designing the mechanical seal as a modular unit ensures the relative positional accuracy of each component, simplifies the installation process, and reduces the risk of early failure due to improper installation. The inner moving ring 10, outer moving ring 6, and stationary ring 7 form a clear power transmission path and sealing interface. The continuous clamping force provided by the elastic element ensures a tight fit of the sealing end faces, and the multiple sealing rings form a multi-layered sealing defense.

[0026] Specifically, the bushing 9 is typically made of metal, such as stainless steel, which offers good strength and corrosion resistance. The inner wall of the bushing 9 is smooth to reduce friction with the pump shaft. Transmission and positioning can be achieved between the bushing 9 and the pump shaft via key connections or other methods, ensuring that the bushing 9 rotates synchronously with the pump shaft. The outer circumferential surface of the bushing 9 is used to mount components such as the inner rotating ring 10; its surface finish is high to ensure the installation accuracy of the inner rotating ring 10. The bushing 9 can also be made of alloy material to meet the requirements of different operating conditions.

[0027] The inner moving ring 10 is generally made of cemented carbide, which has high hardness and wear resistance. The inner wall of the inner moving ring 10 fits tightly against the outer circumferential surface of the bushing 9 and is fixedly connected to the bushing 9 by interference fit or key connection. The outer circumferential surface of the inner moving ring 10 is used to mount the outer moving ring 6 and the stationary ring 7; its surface is precision machined to ensure the mounting accuracy of the outer moving ring 6 and the stationary ring 7. The inner moving ring 10 can also be made of materials such as ceramic to improve its wear resistance and corrosion resistance.

[0028] The outer moving ring 6 is also made of hard alloy or ceramic, and its inner wall is tightly fitted to the outer circumference of the inner moving ring 10, and is fixedly connected to the inner moving ring 10 by means of bonding or mechanical connection. One end of the outer moving ring 6 forms a sealing end face with the stationary ring 7. This sealing end face is ground and polished to ensure good sealing performance. An annular groove may be provided on the outer side of the outer moving ring 6 for installing the second sealing ring 3. The outer moving ring 6 may also be made of composite materials to combine the advantages of different materials.

[0029] The stationary ring 7 is fixed to the gland 12 by an anti-rotation pin, which prevents the stationary ring 7 from rotating with the bushing 9. One end of the stationary ring 7 forms a sealing end face with the outer rotating ring 6, and this sealing end face is fitted to the sealing end face of the outer rotating ring 6. The stationary ring 7 can also be made of materials such as graphite impregnated with resin to improve its strength and wear resistance.

[0030] The gland 12 is generally made of metal, such as cast iron, which has good strength and rigidity. The gland 12 is fitted around the outer circumference of the bushing 9, allowing the bushing 9 to rotate freely. One side of the gland 12 is used to install the stationary ring 7, which is fixed to the gland 12 by an anti-rotation pin. The other side of the gland 12 is connected to the pump body of the water pump and secured by bolts or other fasteners. The gland 12 can also be made of cast steel or other materials to meet different strength requirements.

[0031] The power ring 14 and the bushing 9 are connected by fasteners, such as recessed set screws 15. The fasteners penetrate the power ring 14 and connect to the outer wall of the bushing 9 or the outer moving ring 6, providing reliable power transmission and ensuring that the power ring 14 can effectively drive the bushing 9 and the moving ring assembly to rotate synchronously, preventing wear or seal failure caused by relative sliding. The power ring 14 can also be connected to the bushing 9 using other transmission methods, such as couplings.

[0032] A positioning block 13 is provided between the drive ring and the gland 12. The positioning block 13 is generally made of metal or plastic and has a certain thickness and strength. The positioning block 13 is fixed to the outer surface of the gland 12 by fasteners, which are mostly cylindrical head set screws 16. The function of the positioning block 13 is to further stabilize the relative position of the drive ring and the gland 12, ensuring the stability of the entire mechanical seal structure. The positioning block 13 can also be replaced by a protruding structure with positioning and support functions. The setting of the positioning block 13 enhances the connection stability between the drive ring and the gland 12, avoids the shaking and displacement of the drive ring during operation, thereby improving the reliability and sealing performance of the entire mechanical seal structure.

[0033] The elastic element includes a mounting ring seat 11 and a spring 8. The mounting ring seat 11 is fixedly sleeved on the outer circumference of the inner moving ring 10 and is generally made of metal, such as carbon steel. The inner side of the mounting ring seat 11 has a receiving groove for accommodating the spring 8. The shape and size of the receiving groove match the spring 8 to ensure that the spring 8 can be stably installed within the mounting ring seat 11. One end of the spring 8 is connected to the receiving groove, and the other end presses against the outer moving ring 6 towards the stationary ring 7, forcing the outer moving ring 6 and the stationary ring 7 to press against each other, providing elastic preload to the sealing end face. The spring 8 can be a cylindrical helical spring 8 or a disc spring 8, etc. The mounting ring seat 11 can also be made of aluminum alloy or other materials to reduce weight.

[0034] The first sealing ring 2, the second sealing ring 3, the third sealing ring 5, the fourth sealing ring 4, and the fifth sealing ring 1 are typically made of rubber, such as nitrile rubber or fluororubber, which have good elasticity and sealing performance. The first sealing ring 2 is installed between the inner moving ring 10 and the bushing 9 to prevent media leakage from the inside of the bushing 9. The second sealing ring 3 is installed between the outer moving ring 6 and the inner moving ring 10 to prevent media leakage from the inside of the mechanical seal cavity. The third sealing ring 5 is installed between the gland 12 and the stationary ring 7 to prevent media leakage from the mating surface of the gland 12 and the stationary ring 7. The fourth sealing ring 4 is installed between the gland 12 and the pump contact surface to prevent media leakage from the mating surface of the gland 12 and the pump. The fifth sealing ring 1 is installed between the bushing 9 and the outer circumferential surface of the pump shaft to prevent media leakage from the mating surface of the bushing 9 and the pump shaft. Other sealing materials, such as polytetrafluoroethylene (PTFE), can also be used for the sealing rings.

[0035] In this embodiment, the cartridge mechanical seal structure further includes a flushing structure D. The flushing structure D includes a flushing water inlet and a distribution channel located within the end cap. The flushing water inlet is connected to an external flushing medium supply source, typically via a pipeline connection. The distribution channel surrounds the sealing end face and connects to the flushing water inlet; it is generally an annular channel machined into the gland 12 or related components. After entering the distribution channel from the inlet, the flushing water evenly flushes the rotating ring, stationary ring 7, and their sealing end faces, carrying away impurities and heat between the sealing surfaces. The distribution channel can also be designed as multiple branch pipes.

[0036] The implementation principle of this embodiment is as follows: The modular mechanical seal structure of this embodiment designs each component as an integral module, which is convenient to install, ensures the relative positional accuracy of each component, and reduces the risk of failure due to improper installation. The structural design of the inner moving ring 10, outer moving ring 6, and stationary ring 7 forms a clear power transmission path and sealing interface. The elastic preload provided by the elastic element ensures a tight fit of the sealing end face, maintaining a stable sealing pressure even when there is slight shaft movement. The multiple sealing rings form multiple sealing defenses, effectively blocking the leakage path of the medium, significantly improving the overall reliability of the sealing structure, extending the service life of the sealing structure, and reducing maintenance costs. Compared with the traditional packing seal method, this represents a significant improvement.

[0037] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A cartridge-type mechanical seal structure for use in water pumps, characterized in that: The system includes a bushing (9), a cover (12), an inner moving ring (10), an outer moving ring (6), a stationary ring (7), a cover (12), a power ring (14), and an elastic element. The bushing (9) is fitted onto the outer circumference of the pump shaft. The cover (12) is fitted onto the outer circumference of the bushing (9). The inner moving ring (10) is fitted onto the outer circumference of the bushing (9) and is fixedly connected to the bushing (9). The outer moving ring (6) and the stationary ring (7) are both fitted onto the outer circumference of the inner moving ring (10) and distributed along the axial direction of the bushing (9). The outer moving ring (6) and the stationary ring (7) are fitted together to form a sealing end face. The outer moving ring (6) is fixedly connected to the inner moving ring (10). The stationary ring (7) is fixed to the anti-rotation pin of the pressure cap (12). A first sealing ring (2) is provided between the inner moving ring (10) and the bushing (9). A second sealing ring (3) is provided between the outer moving ring (6) and the inner moving ring (10). The elastic element is used to force the outer moving ring (6) and the stationary ring (7) to abut against each other, providing elastic preload force for the sealing end face.

2. The cartridge mechanical seal structure for use in water pumps according to claim 1, characterized in that: The power ring (14) and the bushing (9) are connected by fasteners, which pass through the power ring (14) and are connected to the outer wall of the bushing (9).

3. The cartridge mechanical seal structure for use in water pumps according to claim 1, characterized in that: The elastic element includes a mounting ring seat (11) and a spring (8). The mounting ring seat (11) is fixedly sleeved on the outer circumferential surface of the inner moving ring (10). The inner side of the mounting ring seat (11) is provided with a receiving groove for accommodating the spring (8). One end of the spring (8) is connected to the receiving groove, and the other end of the spring (8) presses against the outer moving ring (6) in the direction of the stationary ring (7), forcing the outer moving ring (6) and the stationary ring (7) to press against each other, providing elastic preload force for the sealing end face.

4. The cartridge mechanical seal structure for use in water pumps according to claim 3, characterized in that: A pressure ring is provided on the outer side of the mounting ring seat (11). The pressure ring extends to the outer side of the outer moving ring (6). The pressure ring applies a clamping force to the outer moving ring (6) in a manner that faces the inner moving ring (10), so that the outer moving ring (6) and the inner moving ring (10) abut against each other.

5. A cartridge mechanical seal structure for use in a water pump according to claim 4, characterized in that: The outer moving ring (6) has an annular groove on the side near the mounting ring seat (11) for accommodating the second sealing ring (3), and the spring (8) applies a clamping force to both the outer moving ring (6) and the second sealing ring (3) at the end facing the stationary ring (7).

6. The cartridge mechanical seal structure for use in a water pump according to claim 1, characterized in that: It also includes a flushing structure (D), which includes a flushing water inlet and a distribution channel disposed at the pressure cap (12), the distribution channel being disposed around the sealing end face and communicating with the flushing water inlet.

7. A cartridge mechanical seal structure for use in a water pump according to claim 1, characterized in that: A third sealing ring (5) is provided between the pressure cap (12) and the stationary ring (7).

8. The cartridge mechanical seal structure for use in water pumps according to claim 1, characterized in that: The pressure cap (12) is provided with a fourth sealing ring (4) on the contact surface with the water pump.

9. A cartridge mechanical seal structure for use in a water pump according to claim 1, characterized in that: A fifth sealing ring (1) is provided between the bushing (9) and the outer circumferential surface of the pump shaft.

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