Mechanical seal with pressure adjusting structure
By designing a mechanical seal with a pressure regulating structure and using a slide groove and spring buffer module to achieve self-balancing, the problem of end face damage of the mechanical seal under axial pressure is solved, and the sealing reliability and service life of the equipment are improved.
Patent Information
- Application Number
- CN202422276969.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-09-14
AI Technical Summary
Existing mechanical seals are easily damaged when subjected to axial pressure, resulting in damage to the end face and affecting the sealing performance and reliability of the equipment.
A mechanical seal with a pressure regulation structure is designed, which includes an axial buffer unit, a stationary ring unit and a rotating ring unit. The slideway buffer module and the spring buffer module are used to achieve self-balancing, buffer the axial impact force and avoid end face damage.
It effectively avoids damage to the mechanical seal end face, improves seal reliability and service life, reduces maintenance workload, and is suitable for mechanical equipment in chemical, petroleum, pharmaceutical and other industries.
Smart Images
Figure CN223483427U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of mechanical seal technology, and relates to a mechanical seal structure, especially a mechanical seal with a pressure regulating structure. Background Technology
[0002] Mechanical seals are essential components in mechanical equipment such as centrifugal pumps, centrifuges, and reactors, used to improve the sealing level and extend the safe operating period of the equipment. The main indicators for evaluating mechanical seals are leakage rate, reliability, and service life. Improper performance in any of these aspects will negatively affect the seal's performance.
[0003] Because the drive shaft runs through both the inside and outside of the equipment, a certain gap exists between the shaft and the equipment to ensure its normal operation. To prevent the medium inside the equipment from leaking out through this gap, and also to prevent air from rushing into the equipment when the internal pressure is lower than atmospheric pressure, affecting its operation, a mechanical seal is needed to eliminate the gap between the drive shaft and the equipment. The most significant failure of existing mechanical seals is that when subjected to a large external pressure difference, the seal face collides with the equipment and breaks under stress. After the seal face breaks, the cooling water used to cool the drive shaft and the seal enters the equipment, contaminating the materials inside.
[0004] Therefore, it is necessary to provide a mechanical seal that can buffer the pressure when subjected to impact pressure along the drive shaft axis, prevent it from colliding with the equipment, thereby avoiding damage to the end face of the mechanical seal and ensuring the stable operation of the equipment. Utility Model Content
[0005] The purpose of this invention is to provide a mechanical seal with a pressure regulating structure to solve the technical problem that the end face of the mechanical seal is easily damaged when subjected to axial pressure in the prior art.
[0006] To achieve the above objectives, the specific technical solution of this utility model is as follows:
[0007] A mechanical seal with a pressure regulating structure includes a bushing, and further includes an axial buffer unit, a stationary ring unit, and a rotating ring unit, which are respectively fitted onto the bushing and arranged adjacent to each other in sequence. The axial buffer unit includes a groove buffer module. The bushing is provided with a U-shaped groove that cooperates with the groove buffer module and extends axially. The groove buffer module includes a moving ring seat and an adjusting positioning screw. The moving ring seat is fitted onto the bushing and positioned above the U-shaped groove. The moving ring seat is provided with a threaded hole. The adjusting positioning screw is disposed in the threaded hole. The lower end of the adjusting positioning screw passes through the threaded hole and extends into the U-shaped groove, having the degree of freedom to displace relative to the bushing along the extension direction of the U-shaped groove when subjected to axial force.
[0008] The axial buffer unit also includes a spring buffer module, which includes a compression spring. The moving ring seat has a T-shaped structure, and a spring groove is provided on the side of the vertical part of the moving ring seat. One end of the compression spring is inserted into the spring groove, and the other end is in contact with the rotating ring unit. The upper end surface of the rotating ring unit is engaged with the bottom surface of the horizontal part of the moving ring seat.
[0009] The rotating ring unit includes a positioning ring, a rotating ring sealing ring, a rotating ring body, and a rotating ring sealing surface arranged sequentially. The rotating ring body is T-shaped. The positioning ring is in contact with the axial buffer unit. The rotating ring sealing ring and the rotating ring sealing surface are respectively disposed in the space below the two sides of the rotating ring body. The rotating ring sealing ring is located on one side of the positioning ring and is in contact with the positioning ring. The rotating ring sealing surface is located on one side of the stationary ring unit. The surface of the rotating ring sealing surface is smooth and is in close contact with the stationary ring unit, and is in clearance fit with the rotating ring body.
[0010] The stationary ring unit includes a stationary ring sealing surface, a stationary ring body, and a stationary ring sealing ring arranged sequentially. The outer side of the stationary ring body is stepped and shaft-shaped. An installation groove is provided at the lower part of the end face of the large step of the stationary ring body. The stationary ring sealing surface is fitted into the installation groove of the stationary ring body. The surface of the stationary ring sealing surface is smooth and in close contact with the rotating ring unit. The stationary ring sealing ring is located at the shoulder of the stationary ring body and seals against external parts.
[0011] The rotating ring unit, the stationary ring unit, and the spring buffer module are each in two sets, symmetrically arranged on the left and right sides of the slide buffer module.
[0012] It also includes an auxiliary positioning unit, which includes a fastening screw, an auxiliary positioning hole, and a U-shaped microgroove. The U-shaped microgroove is disposed on the outer surface of the drive shaft and extends along the axial direction of the drive shaft. The auxiliary positioning hole is disposed at one end of the bushing, penetrates the side wall of the bushing, and is located above the U-shaped microgroove. The length of the fastening screw is greater than the height between the outer surface of the bushing and the bottom surface of the U-shaped microgroove, and it is threadedly engaged with the auxiliary positioning hole, providing the freedom to tighten and loosen the drive shaft.
[0013] The beneficial effects of this utility model are as follows: This utility model provides a mechanical seal with a pressure regulating structure. By setting a sliding groove buffer module, the two ends of the mechanical seal can undergo slight axial sliding relative to the bushing when the internal and external pressure difference is unbalanced or when subjected to axial pressure or impact force, so as to achieve self-balancing. Furthermore, by setting a sliding groove buffer module and combining it with the mechanical seal, the self-balancing ability of the mechanical seal can be further improved, thereby effectively avoiding end face failure of the mechanical seal and preventing external cooling water from entering the internal contaminants of equipment such as centrifugal pumps, centrifuges, and reactors.
[0014] This invention improves the service life of mechanical seals by utilizing a simple structure, thereby effectively ensuring the sealing reliability and durability of mechanical seals. Furthermore, its simple structure, low manufacturing cost, and short installation time greatly reduce the workload of maintenance personnel, making it suitable for promotion and application in mechanical equipment in chemical, petroleum, and pharmaceutical industries. Attached Figure Description
[0015] Figure 1 This is a cross-sectional view of the application of this utility model on a drive shaft;
[0016] The markings in the diagram are as follows: 1. Bushing, 2. U-groove, 3. Rotary ring seat, 4. Adjusting and positioning screw, 5. Compression spring, 6. Positioning ring, 7. Rotary ring seal, 8. Rotary ring body, 9. Rotary ring sealing surface, 10. Stationary ring sealing surface, 11. Stationary ring body, 12. Stationary ring seal, 13. Fastening screw, 14. U-groove, 15. Drive shaft. Detailed Implementation
[0017] To better understand the purpose, structure, and function of this utility model, a more detailed description of this utility model is provided below with reference to the accompanying drawings.
[0018] like Figure 1 As shown, this utility model provides a mechanical seal with a pressure regulating structure, including a bushing 1, and further including an axial buffer unit, a stationary ring unit, and a rotating ring unit respectively fitted onto the bushing 1 and arranged adjacent to each other. The rotating ring unit applies a clamping force to the stationary ring unit under the push of the axial buffer unit. The contact surfaces of the two are smooth. In the working state, a fluid film is formed between the rotating ring unit and the stationary ring unit, thereby achieving dynamic sealing between them. Furthermore, the axial buffer unit in this embodiment also includes a mechanism to balance the internal and external pressure difference of the mechanical seal through its own axial movement. Specifically, the axial buffer unit includes a grooved buffer module, and the bushing 1 is provided with a U-shaped groove 2 that cooperates with the grooved buffer module and extends axially. The slide groove buffer module includes a moving ring seat 3 and an adjusting positioning screw 4. The moving ring seat 3 is fitted onto the bushing 1 and positioned above the U-shaped groove. The rotating ring unit contacts the moving ring seat 3. The moving ring seat 3 is provided with a threaded hole. The adjusting positioning screw 4 is disposed in the threaded hole. The lower end of the adjusting positioning screw 4 passes through the threaded hole and extends into the U-shaped groove. The U-shaped groove provides a limit for the adjusting positioning screw 4, thereby providing a limit for the moving ring seat 3. This allows the moving ring seat 3 to have the freedom to slide relative to the bushing 1 along the extension direction of the U-shaped groove 2 when subjected to axial impact force. This pushes the rotating ring unit and the stationary ring unit to slide slightly axially relative to the bushing 1, thereby eliminating the damage caused by the impact force to the slide groove buffer module, the rotating ring unit, and the stationary ring unit.
[0019] In this embodiment, by inserting the lower end of the adjusting positioning screw 4 into the U-shaped groove 2, when the mechanical seal body is subjected to a large internal and external pressure difference or impact force, the moving ring seat 3 can be displaced relative to the bushing 1, thereby buffering the force on its end face to achieve self-balance and avoid damage to the mechanical seal end face.
[0020] Furthermore, in addition to the sliding groove buffer module, the axial buffer unit in this embodiment also includes a spring buffer module. Specifically, the spring buffer module includes a compression spring 5. The moving ring seat 3 has a T-shaped structure, and a spring groove is formed on the side of the vertical portion of the moving ring seat 3. One end of the compression spring 5 is inserted into the spring groove, and the other end contacts the rotating ring unit. The upper surface of the rotating ring unit mates with the bottom surface of the horizontal portion of the moving ring seat 3. The compression spring 5, when the moving ring seat 3 and the adjusting positioning screw 4 are displaced relative to the bushing 1, automatically pushes the rotating ring unit to continue pressing the stationary ring unit through its own compressive potential energy, keeping the rotating ring unit and the stationary ring unit in close contact and compression. This ensures that a fluid film is maintained between the two during the rotation of the rotating ring unit to maintain a dynamic seal.
[0021] Furthermore, the rotating ring unit in this embodiment includes a positioning ring 6, a rotating ring sealing ring 7, a rotating ring body 8, and a rotating ring sealing surface 9 arranged sequentially. The rotating ring body 8 is T-shaped. The positioning ring 6 is located on one side of the rotating ring body 8, with its upper side contacting the end face of the horizontal portion of the rotating ring body 8 and its lower side contacting and engaging with the axial buffer unit. The rotating ring sealing ring 7 is compressed and disposed in the space between the positioning ring 6 and the rotating ring body 8. The rotating ring sealing surface 9 is disposed in the space between the stationary ring unit and the rotating ring body 8, with a smooth side surface that contacts and engages with the stationary ring unit.
[0022] Meanwhile, the stationary ring unit in this embodiment includes a stationary ring sealing surface 10, a stationary ring body 11, and a stationary ring sealing ring 12 arranged sequentially. The outer side of the stationary ring body 11 is stepped shaft-shaped. An installation groove is opened at the lower part of the end face of the stationary ring body 11 on the side of the large step. The stationary ring sealing surface 10 is engaged in the installation groove of the stationary ring body 11. The side surface of the stationary ring sealing surface 10 is smooth and contacts and cooperates with the side surface of the rotating ring sealing surface 9. Under the action of the compression spring 5, the rotating ring sealing surface 9 presses the stationary ring sealing surface 10. The stationary ring sealing ring 12 is set at the shoulder of the stationary ring body 11 and seals with external parts.
[0023] Furthermore, in order to enable the mechanical seal to have a bidirectional self-balancing function, in this embodiment, the number of rotating ring units, stationary ring units and spring buffer modules are two sets each, symmetrically arranged on the left and right sides of the slide buffer module.
[0024] Furthermore, in order to position the bushing 1 and facilitate the installation of the bushing 1 and various components in the axial buffer unit, stationary ring unit, and rotating ring unit on the drive shaft 15, and also to provide a limit for the bushing 1 so that it can guide the micro-sliding of the bushing 1 when the drive shaft 15 is subjected to axial impact force, the mechanical seal in this embodiment also includes an auxiliary positioning unit, which specifically includes a fastening screw 13, an auxiliary positioning hole, and a U-shaped micro-groove 14. The U-shaped micro-groove 14 is provided on the surface of the drive shaft 15 and extends along the axial direction of the drive shaft 15. The auxiliary positioning hole is provided at one end of the bushing 1 and penetrates the side wall of the bushing 1. After the bushing 1 is fitted onto the drive shaft 15, the auxiliary positioning hole is located above the U-shaped micro-groove 14. In this embodiment, in order to provide a limit for the bushing 1, the length of the fastening screw 13 is set to be greater than the height between the outer surface of the bushing and the bottom surface of the U-shaped micro-groove 14, and it is threadedly engaged with the auxiliary positioning hole.
[0025] When installing the mechanical seal, first use the fastening screw 13 to press the bottom surface of the U-shaped micro-groove 14 of the bushing 1, thereby fixing the position between the bushing 1 and the drive shaft 15. Then install other components onto the bushing. After the mechanical seal is fully assembled, adjust the distance between the rotating ring body 8 and the stationary ring body 11 by using the locking nut of the external impeller. After adjusting the fit of the sealing surface, loosen the fastening screw 13 to disengage the bushing 1 from the drive shaft 15, and keep the lower end of the fastening screw 13 in the U-shaped micro-groove 14. This ensures that the mechanical seal is always in a dynamic sealing state, safe and reliable, and at the same time provides guidance for the bushing 1, ensuring that the equipment still maintains reliable operation under the influence of axial sudden load.
[0026] It is understood that this utility model has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this utility model. Furthermore, under the teachings of this utility model, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this utility model.
Claims
1. A mechanical seal with a pressure regulating structure, comprising a bushing (1), characterized in that: It also includes an axial buffer unit, a stationary ring unit, and a rotating ring unit, which are respectively fitted on the bushing (1) and arranged adjacent to each other in sequence. The axial buffer unit includes a sliding groove buffer module. The bushing (1) is provided with a U-shaped groove (2) that cooperates with the sliding groove buffer module and extends axially. The sliding groove buffer module includes a moving ring seat (3) and an adjusting positioning screw (4). The moving ring seat (3) is fitted on the bushing (1) and is located above the U-shaped groove. The moving ring seat (3) is provided with a threaded hole. The adjusting positioning screw (4) is located in the threaded hole. The lower end of the adjusting positioning screw (4) passes through the threaded hole and extends into the U-shaped groove, and has the degree of freedom to move relative to the bushing (1) along the extension direction of the U-shaped groove (2) when subjected to axial force.
2. The mechanical seal with a pressure regulating structure according to claim 1, characterized in that: The axial buffer unit also includes a spring buffer module, which includes a compression spring (5). The moving ring seat (3) has a T-shaped structure. A spring groove is provided on the side of the vertical part of the moving ring seat (3). One end of the compression spring (5) is inserted into the spring groove, and the other end is in contact with the rotating ring unit. The upper end surface of the rotating ring unit is engaged with the bottom surface of the horizontal part of the moving ring seat (3).
3. A mechanical seal with a pressure regulating structure according to claim 1, characterized in that: The rotating ring unit includes a positioning ring (6), a rotating ring sealing ring (7), a rotating ring body (8), and a rotating ring sealing surface (9) arranged sequentially. The rotating ring body (8) is T-shaped. The positioning ring (6) is in contact with the axial buffer unit. The rotating ring sealing ring (7) and the rotating ring sealing surface (9) are respectively located in the space below the two sides of the rotating ring body (8). The rotating ring sealing ring (7) is located on one side of the positioning ring (6) and is in contact with the positioning ring (6). The rotating ring sealing surface (9) is located on one side of the stationary ring unit. The surface of the rotating ring sealing surface (9) is smooth and is in close contact with the stationary ring unit, and is in clearance fit with the rotating ring body (8).
4. A mechanical seal with a pressure regulating structure according to claim 1, characterized in that: The stationary ring unit includes a stationary ring sealing surface (10), a stationary ring body (11), and a stationary ring sealing ring (12) arranged sequentially. The outer side of the stationary ring body (11) is stepped shaft-shaped. An installation groove is provided at the lower part of the end face of the large step side of the stationary ring body (11). The stationary ring sealing surface (10) is fitted into the installation groove of the stationary ring body (11). The surface of the stationary ring sealing surface (10) is smooth and in close contact with the rotating ring unit. The stationary ring sealing ring (12) is located at the shoulder of the stationary ring body (11) and seals against external parts.
5. A mechanical seal with a pressure regulating structure according to claim 2, characterized in that: The rotating ring unit, the stationary ring unit, and the spring buffer module are each in two sets, symmetrically arranged on the left and right sides of the slide buffer module.
6. A mechanical seal with a pressure regulating structure according to claim 1, characterized in that: It also includes an auxiliary positioning unit, which includes a fastening screw (13), an auxiliary positioning hole and a U-shaped micro-groove (14). The U-shaped micro-groove (14) is disposed on the outer surface of the transmission shaft (15) and extends along the axial direction of the transmission shaft (15). The auxiliary positioning hole is disposed at one end of the bushing (1), penetrates the side wall of the bushing (1), and is located above the U-shaped micro-groove (14). The length of the fastening screw (13) is greater than the height between the outer side of the bushing (1) and the bottom surface of the U-shaped micro-groove (14), and it is threadedly engaged with the auxiliary positioning hole, thus having the freedom to press and release the transmission shaft (15).