Adjusting device for back pressure of centrifugal pump impeller
By introducing moving parts and a pressure accumulator into the centrifugal pump, and utilizing lubricating oil to store and release elastic potential energy, the problem of seal damage caused by unstable pressure on the back of the impeller is solved, thus improving the service life of the mechanical seal.
Patent Information
- Application Number
- CN202423298313.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2034-12-31
AI Technical Summary
Unstable high pressure on the back of the centrifugal pump impeller may damage the mechanical seal or cause it to lose its sealing function.
By employing moving parts and a pressure accumulator, the lubricating oil in the bearing cavity is used to store and release elastic potential energy, thereby regulating the pressure fluctuations on the back of the impeller and protecting the mechanical seal.
It effectively regulates pressure fluctuations on the back of the impeller, protects the mechanical seal, and extends its service life.
Smart Images
Figure CN223578238U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to pump class machinery, concretely relates to centrifugal pump. BACKGROUND
[0002] Centrifugal pump is a kind of pump class machinery that medium is made to centrifugal motion by impeller rotation, and the medium is thrown to the edge of impeller under the action of centrifugal motion to form vacuum in the middle to suck medium. Impeller is installed on the rotating shaft, and mechanical seal is arranged between bearing cavity of rotating shaft and impeller cavity to separate the two cavities, and bearing cavity is filled with lubricating oil. The front of the center of impeller is water inlet, and water inlet is also located in front of mechanical seal, impeller rotates, water inlet pressure decreases, water enters impeller cavity from water inlet, at the same time, the back of impeller is high pressure, if water pressure is unstable, for example, drainage is not smooth, water pressure in impeller cavity rises, the pressure of the back of impeller will rise sharply, which may cause mechanical seal damage or loss of sealing function. SUMMARY
[0003] The utility model solves the technical problem that the back pressure of centrifugal pump impeller, if water pressure is unstable, the pressure of the back of impeller will rise sharply, which may cause mechanical seal damage or loss of sealing function.
[0004] To solve the above technical problem, the utility model provides the following technical scheme: the adjusting device of centrifugal pump impeller back pressure, including movable part and pressure accumulator, the movable part includes disc-shaped part, guide rod fixedly arranged on the disc-shaped part, guide hole is arranged on the mechanical seal between impeller cavity and bearing cavity, the guide hole is connected with impeller cavity and bearing cavity, the guide rod is movably matched in the guide hole, and sealing element is arranged between the guide rod and the guide hole, and the disc-shaped part is located in the bearing cavity;Adjusting hole is formed in the side wall of bearing cavity, and the adjusting hole is connected with the outside of bearing cavity and the inside of bearing cavity, and the pressure accumulator is installed in the adjusting hole.
[0005] According to the above technical scheme, if water pressure is unstable, for example, drainage is not smooth, water pressure in impeller cavity rises, the pressure of the back of impeller rises sharply, the end surface of guide rod is pressed and displaces along the guide hole, and the disc-shaped part retreats. Since the guide rod retreats into the bearing cavity, the volume of the bearing cavity is occupied, according to the incompressible principle of liquid, the lubricating oil in the bearing cavity acts on the pressure accumulator, and the pressure accumulator accumulates elastic potential energy. After the pressure of the back of impeller decreases, the pressure accumulator releases elastic potential energy, and the disc-shaped part and the guide rod advance to reset.
[0006] The inner side wall of the guide hole is provided with a plurality of ring grooves, and a piston ring is matched in each ring groove, and the piston ring is sleeved on the guide rod. The piston ring plays a sealing role and blocks the bearing cavity and the impeller cavity. As an option, the piston ring is an open piston ring, and the openings of the plurality of open piston rings are staggered.
[0007] The disc-shaped part is provided with a center hole, and is matched with the rotating shaft, the inner diameter of the inner convex part on the inner side wall of the bearing cavity is smaller than the outer diameter of the disc-shaped part, and the disc-shaped part is located between the mechanical seal and the inner convex part. The inner convex part is used for installing the bearing, and the inner convex part can block the excessively retreated disc-shaped part, and limits the disc-shaped part.
[0008] The rotating shaft is sleeved with a limiting ring, the limiting ring is located in the bearing cavity, the limiting ring is located between the mechanical seal and the step of the rotating shaft, and the outer diameter of the limiting ring is greater than the inner diameter of the center hole of the disc-shaped part. The limiting ring limits the advancing amplitude of the disc-shaped part.
[0009] The pressure storage device comprises a piston and a spring, the front face of the piston is communicated with the inside of the bearing cavity, the back face of the piston is communicated with the outside of the bearing cavity, and the spring is arranged on the back face of the piston. The lubricating oil in the bearing cavity acts on the piston, the piston compresses the spring, the spring accumulates elastic potential energy, and thus energy is stored.
[0010] The piston is matched in the center hole of the first threaded part, the first threaded part is screwed in the adjusting hole, the spring is sleeved on the piston rod and located in the center hole of the first threaded part, the second threaded part is screwed in the center hole of the first threaded part, the second threaded part limits the spring in the center hole of the first threaded part, and the second threaded part is provided with a gap hole matched with the piston rod.
[0011] The utility model discloses utilize the lubricating oil in bearing cavity as medium, store high pressure from the back of impeller in pressure storage device, release the energy in pressure storage device again under the pressure of the back of impeller. Thus, the movable part and the pressure storage device used in cooperation can absorb the excessively high pressure of the back of impeller, not only adjust the pressure of the impeller cavity, but also protect the mechanical seal between the bearing cavity and the impeller cavity, and prolong the service life. BRIEF DESCRIPTION OF DRAWINGS
[0012] The utility model will be further explained in connection with the drawings:
[0013] Figure 1 It is the schematic diagram of centrifugal pump with adjusting device;
[0014] Figure 2 It is Figure 1 The enlarged view of A in the middle;
[0015] Figure 3 It is the schematic diagram of movable part 10;
[0016] Figure 4 It is Figure 3 The left view of;
[0017] Figure 5 It is Figure 1 The schematic diagram of pressure storage device 20 in the middle.
[0018] Explanation of symbols in the drawing:
[0019] 10, moving part; 11, disc-shaped part; 110, central hole; 12, guide rod; 13, piston ring; 14, limiting ring;
[0020] 20, pressure accumulator; 21, piston; 22, spring; 23, first threaded part; 24, second threaded part; 25, piston rod; 26, sealing ring;
[0021] 30, mechanical seal; 31, impeller cavity; 32, bearing cavity; 33, rotating shaft; 34, inner convex part on the inner side wall of the bearing cavity; 35, impeller. DETAILED DESCRIPTION
[0022] In combination Figure 1 , Figure 2 , the adjusting device for the back pressure of the impeller of a centrifugal pump comprises a moving part 10 and a pressure accumulator 20. The moving part comprises a disc-shaped part 11 and a guide rod 12 fixedly arranged on the disc-shaped part. A guide hole is arranged on the mechanical seal 30 between the impeller cavity 31 and the bearing cavity 32, and the guide hole is in communication with the impeller cavity and the bearing cavity. The guide rod is movably fitted in the guide hole, and a sealing member is arranged between the guide rod and the guide hole. The disc-shaped part is located in the bearing cavity. An adjusting hole is arranged on the side wall of the bearing cavity, and the adjusting hole is in communication with the outside of the bearing cavity and the inside of the bearing cavity. The pressure accumulator 20 is installed in the adjusting hole.
[0023] A plurality of ring grooves are arranged on the inner side wall of the guide hole, and each ring groove is fitted with a piston ring 13. The piston ring is sleeved on the guide rod 12.
[0024] The disc-shaped part 11 is provided with a central hole 110. The disc-shaped part is fitted on the rotating shaft 33. The inner diameter of the inner convex part 34 on the inner side wall of the bearing cavity is smaller than the outer diameter of the disc-shaped part 11. The disc-shaped part is located between the mechanical seal 30 and the inner convex part.
[0025] A limiting ring 14 is sleeved on the rotating shaft 33, and the limiting ring is located in the bearing cavity 32. The limiting ring is located between the mechanical seal 30 and the step of the rotating shaft. The outer diameter of the limiting ring is greater than the inner diameter of the central hole 110 of the disc-shaped part.
[0026] As Figure 5 , the pressure accumulator 20 comprises a piston 21 and a spring 22. The front face of the piston is in communication with the inside of the bearing cavity 32, the back face of the piston is in communication with the outside of the bearing cavity, and the spring is arranged on the back face of the piston.
[0027] The piston 21 is fitted in the central hole of the first threaded part 23. The first threaded part is screwed in the adjusting hole. The spring 22 is sleeved on the piston rod and located in the central hole of the first threaded part. The second threaded part 24 is screwed in the central hole of the first threaded part, and the second threaded part limits the spring in the central hole of the first threaded part. The second threaded part is provided with a clearance hole matched with the piston rod 25.
[0028] Reference Figure 1 If the water pressure is unstable, the water pressure in the impeller cavity 31 rises, the pressure on the back of the impeller 35 rises sharply, the end surface of the guide rod 12 is pressed and displaced along the guide hole, and the disc-shaped part 11 retreats. Since the guide rod 12 retreats into the bearing cavity 32, the lubricating oil in the bearing cavity acts on the pressure accumulator 20, and the pressure accumulator accumulates elastic potential energy. Specifically, the lubricating oil in the bearing cavity 32 acts on the piston 21, the piston compresses the spring 22, and the spring accumulates elastic potential energy, so that the energy is stored. After the pressure on the back of the impeller 35 decreases, the pressure accumulator 20 releases the elastic potential energy, and the disc-shaped part 11 and the guide rod 12 advance and reset.
[0029] The above is only a preferred embodiment of the present application, and for those skilled in the art, according to the idea of the present application, the specific embodiment and application range can be changed, and the content of the specification should not be understood as a limitation of the present application.
Claims
1. A device for regulating the back pressure of a centrifugal pump impeller, comprising a mobile element (10) and a pressure accumulator (20), said mobile element comprising a disc (11) and a guide rod (12) fixed to the disc, characterised in that: The mechanical seal (30) between the impeller cavity (31) and the bearing cavity (32) is provided with a guide hole, the guide hole communicates the impeller cavity and the bearing cavity, a guide rod is movably fitted in the guide hole, a sealing element is arranged between the guide rod and the guide hole, and the disc-shaped piece is located in the bearing cavity; an adjusting hole is formed in the side wall of the bearing cavity, the adjusting hole communicates the outside of the bearing cavity and the inside of the bearing cavity, and the pressure accumulator (20) is mounted in the adjusting hole.
2. The device for regulating the back pressure of a centrifugal pump impeller according to claim 1, characterized in that: A plurality of ring grooves are formed in the inner side wall of the guide hole, and a piston ring (13) is fitted in each ring groove, the piston ring being sleeved on the guide rod (12).
3. The device for regulating the back pressure of a centrifugal pump impeller according to claim 1, characterized in that: The disc-shaped piece (11) is provided with a central hole (110), the disc-shaped piece being fitted on the rotating shaft (33), the inner diameter of the inner convex part (34) on the inner side wall of the bearing cavity being smaller than the outer diameter of the disc-shaped piece (11), and the disc-shaped piece being located between the mechanical seal (30) and the inner convex part.
4. The device for regulating the back pressure of a centrifugal pump impeller according to claim 3, characterized in that: A limiting ring (14) is sleeved on the rotating shaft (33), the limiting ring being located in the bearing cavity (32), the limiting ring being located between the mechanical seal (30) and the step of the rotating shaft, and the outer diameter of the limiting ring being greater than the inner diameter of the central hole (110) of the disc-shaped piece.
5. The device for regulating the back pressure of a centrifugal pump impeller according to claim 1, characterized in that: The pressure accumulator (20) comprises a piston (21) and a spring (22), the front face of the piston communicating the inside of the bearing cavity (32), the back face of the piston communicating the outside of the bearing cavity, and the spring being arranged on the back face of the piston.
6. The device for regulating the back pressure of a centrifugal pump impeller according to claim 5, characterized in that: The piston (21) is fitted in the central hole of a first threaded member (23), the first threaded member being screwed in the adjusting hole, the spring (22) being sleeved on the piston rod and located in the central hole of the first threaded member, a second threaded member (24) being screwed in the central hole of the first threaded member, the second threaded member limiting the spring in the central hole of the first threaded member, and the second threaded member being provided with a relief hole fitted with the piston rod (25).