Built-in double-end-face mechanical seal

Abstract

The built-in double-end-face mechanical seal comprises a sealing box, a static ring is arranged in the front end of the sealing box, the front end of the static ring is tightly attached to a movable ring, the rear end of the static ring is arranged on a static ring base, and a material blocking ring is arranged between the static ring and an opening in the front end of the sealing box. A water seal seat is arranged at the position of a step inside the rear end of the sealing box, a water seal static ring is arranged in the water seal seat, a water seal moving ring is arranged at the rear end of the water seal static ring in a tightly attached mode, and a water seal static ring positioning piece is arranged at the front end of the water seal static ring. A plurality of springs are evenly distributed between the water seal static ring positioning piece and the static ring base in the circumferential direction. The double-end-face sealing structure is compact in structure and small in occupied space, and compared with a traditional double-end-face sealing structure, the using number of O-shaped rings is reduced, errors are reduced, and the mechanical sealing failure risk is reduced; installation of the mechanical seal is simplified, and working efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of mechanical seal technology, and in particular to an internal double-end mechanical seal. Background Technology

[0002] A mechanical seal is a device that prevents fluid leakage by maintaining contact and relative sliding between at least one pair of end faces perpendicular to the axis of rotation under the action of fluid pressure, the elastic force of the compensation mechanism, and the cooperation of auxiliary seals. It is widely used in various mechanical equipment. Based on its structural form, it can be classified into single-end-face mechanical seals and double-end-face mechanical seals. Based on the installation position of the stationary ring, it can be classified into internal mechanical seals and external mechanical seals. Internal mechanical seals can be used in high-temperature and high-pressure environments, can transport slurries, and offer excellent sealing performance.

[0003] In existing technologies, internal double-end mechanical seals typically require more than ten O-rings for sealing, resulting in a complex structure and increased installation difficulty. Furthermore, the dimensional accuracy and surface finish of the O-rings have a significant impact on their sealing performance. If the O-rings are not dimensionally accurate or have a rough surface, it may lead to seal failure. Using a large number of O-rings increases the risk of seal failure. Summary of the Invention

[0004] The purpose of this invention is to solve the above-mentioned technical problems and provide an internal double-end mechanical seal, which simplifies the structure of the double-end mechanical seal and increases its reliability.

[0005] To achieve the above technical objectives and requirements, the technical solution adopted by this utility model is as follows: an internal double-end mechanical seal, comprising a sealing box, the sealing box being disposed on one side of the pump cover, a stationary ring being disposed inside the front end of the sealing box, the front end of the stationary ring being tightly fitted with a rotating ring, the rear end of the stationary ring being disposed on a stationary ring seat, and a retaining ring being disposed between the stationary ring and the front opening of the sealing box; a water seal seat being disposed at the inner step of the rear end of the sealing box, a retaining spring being embedded inside the sealing box on one side of the water seal seat, a water seal stationary ring being disposed inside the water seal seat, a water seal rotating ring being tightly fitted at the rear end of the water seal stationary ring, a water seal stationary ring positioning piece being disposed at the front end of the water seal stationary ring, and a plurality of springs being evenly distributed along the circumferential direction between the water seal stationary ring positioning piece and the stationary ring seat, one end of the spring being disposed on the water seal stationary ring positioning piece, and the other end being disposed on the stationary ring seat.

[0006] Preferably, it further includes a pump shaft, which sequentially passes through a water seal moving ring, a water seal stationary ring, a water seal stationary ring positioning plate, a stationary ring seat, a stationary ring, and a moving ring, and connects to the rear end of the impeller. A shaft sleeve is provided on the pump shaft, and the water seal moving ring is located at the rear end step of the shaft sleeve. A water seal moving ring O-ring is provided between the water seal moving ring and the rear end step of the shaft sleeve. A water seal seat O-ring is provided between the water seal seat and the sealing box. A water seal stationary ring O-ring is provided between the water seal stationary ring and the water seal seat. A stationary ring O-ring is provided between the stationary ring and the sealing box. A moving ring O-ring is provided between the moving ring and the rear end step of the impeller. A water seal cavity is formed between the water seal moving ring, water seal stationary ring, water seal stationary ring positioning plate, stationary ring seat, stationary ring, moving ring, shaft sleeve, and sealing box.

[0007] Preferably, the sealed box is equipped with two external cooling water nozzles.

[0008] Preferably, a water seal locating pin is provided between the water seal moving ring and the bushing.

[0009] Preferably, the water seal stationary ring positioning plate has several sets of spring holes evenly distributed along the circumferential direction on the end face opposite to the stationary ring seat, and the two ends of the spring are respectively set in the corresponding spring holes.

[0010] Preferably, the stationary ring seat has an axial positioning boss at the front end and an annular groove at the rear end, and the stationary ring and the stationary ring seat are positioned by the axial positioning boss and the annular groove.

[0011] Compared with the traditional structure, the beneficial effects of this utility model are:

[0012] 1. This utility model has a compact structure and adopts an internal structure, which occupies little space. The metal bushing does not come into contact with the slurry, and it can transport high-concentration corrosive slurry. Compared with the traditional double-end face sealing structure, it reduces the number of O-rings used. Only 5 O-rings are needed to meet the sealing requirements, reduce errors, and lower the risk of mechanical seal failure. It simplifies the installation of mechanical seal and improves work efficiency.

[0013] 2. The single-group multi-spring structure design ensures balanced force on the sealing end face and saves axial space.

[0014] 3. By setting up a baffle ring, jamming will not occur even when conveying high-concentration slurry, thus improving the reliability of use. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] In the diagram: 1. Impeller, 2. Pump cover, 3. Rotating ring O-ring, 4. Material retainer ring, 5. Stationary ring seat, 6. Spring, 7. Sealing box, 8. Water seal rotating ring O-ring, 9. Water seal stationary ring O-ring, 10. Water seal seat, 11. Water seal seat O-ring, 12. Rotating ring, 13. Stationary ring, 14. Shaft sleeve, 15. Water seal rotating ring locating pin, 16. Water seal rotating ring, 17. Water seal stationary ring, 18. Snap ring, 19. Water seal stationary ring locating plate, 20. Stationary ring O-ring, 21. External cooling water nozzle, 22. Pump shaft. Detailed Implementation

[0017] The present invention will be further described below.

[0018] See attached document Figure 1 An internal double-end mechanical seal includes a sealing box 7, which is disposed on one side of a pump cover 2. A stationary ring 13 is disposed inside the front end of the sealing box 7, and the front end of the stationary ring 13 is tightly fitted with a rotating ring 12. The rear end of the stationary ring 13 is disposed on a stationary ring seat 5. A retaining ring 4 is disposed between the stationary ring 13 and the front opening of the sealing box 7. A water seal seat 10 is disposed at the step inside the rear end of the sealing box 7. A retaining spring 18 is embedded inside the sealing box 7 located on one side of the water seal seat 10. A water seal stationary ring 17 is disposed inside the water seal seat 10. A water seal rotating ring 16 is tightly fitted to the rear end of the water seal stationary ring 17. A water seal stationary ring positioning piece 19 is disposed at the front end of the water seal stationary ring 17. A plurality of springs 6 are evenly distributed along the circumferential direction between the water seal stationary ring positioning piece 19 and the stationary ring seat 5. One end of each spring 6 is disposed on the water seal stationary ring positioning piece 19, and the other end is disposed on the stationary ring seat 5.

[0019] In this preferred embodiment, a pump shaft 22 is also included. The pump shaft 22 passes sequentially through a water seal moving ring 16, a water seal stationary ring 17, a water seal stationary ring positioning piece 19, a stationary ring seat 5, a stationary ring 13, and a moving ring 12, and is connected to the rear end of the impeller 1. A shaft sleeve 14 is provided on the pump shaft 22. The water seal moving ring 16 is located at the rear end step of the shaft sleeve 14. A water seal moving ring O-ring 8 is provided between the water seal moving ring 16 and the rear end step of the shaft sleeve 14. The water seal seat 10 and the sealing box are connected. A water seal seat O-ring 11 is provided between 7, a water seal stationary ring O-ring 9 is provided between the water seal stationary ring 17 and the water seal seat 10, a stationary ring O-ring 20 is provided between the stationary ring 13 and the sealing box 7, and a moving ring O-ring 3 is provided between the moving ring 12 and the rear end step of the impeller 1. The water seal moving ring 16, water seal stationary ring 17, water seal stationary ring positioning piece 19, stationary ring seat 5, stationary ring 13, moving ring 12, shaft sleeve 14, and sealing box 7 form a water seal cavity.

[0020] In this preferred embodiment, the sealed box 7 is provided with two external cooling water nozzles 21, which are distributed at a horizontal angle, one for inlet and one for outlet.

[0021] In this preferred embodiment, a water seal locating pin 15 is provided between the water seal moving ring 16 and the bushing 14.

[0022] In this preferred embodiment, the end face of the water seal stationary ring positioning piece 19 opposite to the stationary ring seat 5 is evenly distributed with a number of spring holes along the circumferential direction, and the two ends of the spring 6 are respectively set in the corresponding spring holes.

[0023] In this preferred embodiment, the front end of the stationary ring seat 5 is provided with an axial positioning boss, and the rear end of the stationary ring 13 is provided with an annular groove. The stationary ring 13 and the stationary ring seat 5 are positioned by the axial positioning boss and the annular groove.

[0024] In practical implementation, this utility model adopts an internal structure, occupying little space. The metal bushing does not contact the slurry, allowing for the transport of high-concentration corrosive slurries. It is suitable for high-pressure, hazardous media, or conditions containing solid particles. Even when transporting high-concentration slurries, it will not jam or leak, providing excellent sealing. The single-set multi-spring structure ensures that the rotating ring, stationary ring, and stationary ring seat are all pressed together to achieve a seal. Combined with a water seal design, the cooling medium enters the mechanical seal from one external cooling water nozzle 21, circulates between the water seal rotating ring 16, water seal stationary ring 17, stationary ring 13, and rotating ring 12, and then flows out from another external cooling water nozzle 21, serving to isolate, lubricate, cool, and prevent media leakage. A baffle ring 4 is installed at the opening where the sealing box 7 contacts the pump cover 2, preventing jamming even when transporting high-concentration slurries, thus improving reliability. Compared with the traditional double-end face sealing structure, it reduces the number of O-rings used, requiring only 5 O-rings to meet the sealing requirements, reducing errors and lowering the risk of mechanical seal failure; it also simplifies the installation of the mechanical seal and improves work efficiency.

[0025] The above embodiments of this utility model are merely examples to clearly illustrate this utility model, and are not intended to limit the scope of protection of this utility model. All equivalent technical solutions also fall within the scope of this utility model, and the patent protection scope of this utility model should be defined by each claim.

Claims

1. A canned double mechanical seal, characterized by: The utility model provides a pump sealing structure, including sealed box (7), sealed box (7) is arranged in pump cover (2) one side, the inside static ring (13) of sealed box (7) front end is tightly attached to dynamic ring (12) front end, static ring (13) rear end is arranged in static ring seat (5), and static ring (13) is tightly attached to the material blocking ring (4) between sealed box (7) front end opening, the inside stepped portion of sealed box (7) rear end is provided with water seal seat (10), and the inside of sealed box (7) is embedded with snap spring (18) in water seal seat (10) one side, and water seal seat (10) is provided with water seal static ring (17), and water seal static ring (17) rear end is tightly attached to water seal dynamic ring (16), and water seal static ring (17) front end is provided with water seal static ring positioning piece (19), and water seal static ring positioning piece (19) and static ring seat (5) between the circumferential direction evenly distributed with a plurality of spring (6) is provided, and one end of spring (6) is arranged on water seal static ring positioning piece (19), and the other end is arranged on static ring seat (5).

2. The built-in double mechanical seal according to claim 1, characterized in that: Also including pump shaft (22), pump shaft (22) is connected in sequence through water seal dynamic ring (16), water seal static ring (17), water seal static ring positioning piece (19), static ring seat (5), static ring (13), dynamic ring (12) and impeller (1) rear end, and the rear end stepped portion of pump shaft (22) is provided with shaft sleeve (14), and water seal dynamic ring (16) is arranged in the rear end stepped portion of shaft sleeve (14), and water seal dynamic ring O type ring (8) is arranged between water seal dynamic ring (16) and the rear end stepped portion of shaft sleeve (14), and water seal seat O type ring (11) is arranged between water seal seat (10) and sealed box (7), and water seal static ring O type ring (9) is arranged between water seal static ring (17) and water seal seat (10), and static ring O type ring (20) is arranged between static ring (13) and sealed box (7), and dynamic ring O type ring (3) is arranged between dynamic ring (12) and the rear end stepped portion of impeller (1), and the rear end stepped portion of pump shaft (22) is provided with shaft sleeve (14), and water seal dynamic ring (16), water seal static ring (17), water seal static ring positioning piece (19), static ring seat (5), static ring (13), dynamic ring (12) and sealed box (7) form water seal cavity.

3. The built-in double mechanical seal according to claim 1, characterized in that: Two external cooling water nozzles (21) are arranged on the sealed box (7).

4. The built-in double mechanical seal of claim 1, wherein: A water seal dynamic ring positioning pin (15) is arranged between the water seal dynamic ring (16) and the shaft sleeve (14).

5. The built-in double mechanical seal of claim 1, wherein: The end faces of the water seal static ring positioning piece (19) and the static ring seat (5) opposite to each other are evenly distributed with a plurality of groups of spring holes in the circumferential direction, and the two ends of the spring (6) are arranged in the corresponding spring holes, respectively.

6. The built-in double mechanical seal of claim 1, wherein: An axial positioning boss is arranged at the front end of the static ring seat (5), an annular groove is arranged at the rear end of the static ring (13), and the static ring (13) and the static ring seat (5) are positioned by the axial positioning boss and the annular groove.

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