A high-sealing vertical stamping multi-stage pump

Abstract

This invention discloses a high-sealing vertical stamping multistage pump, aiming to solve the shortcomings of existing technologies where the motor and pump barrel are sealed by a sealing disc, leading to easy leakage between the pump barrel and motor. The invention solves the above-mentioned technical problems through the following technical solution: It includes a pump barrel, with a motor mounted on the top of the pump barrel; a high-pressure water pipe, one end of which is connected to the high-pressure outlet of the vertical multistage pump, and the other end connected to a water inlet channel; a pump shaft connected to the output end of the motor; a sealing seat mounted on the top of the pump barrel, with a cavity corresponding to the pump shaft; a perforation on the sealing seat; an air bladder inside the cavity; a small annular groove on the side wall of the perforation; a sealing ring inside the small annular groove; and an air passage inside the sealing seat, with both ends connecting the air bladder and the hollow portion of the sealing ring. High-pressure water flows into the cavity from the high-pressure water pipe, compressing the gas inside the air bladder into the sealing ring, thereby improving the sealing effect.

Description

Technical Field

[0001] This invention relates to the field of vertical multistage pump technology, and more specifically, to a high-sealing vertical stamping multistage pump. Background Technology

[0002] Vertical multistage pumps are mechanical devices that can transport liquids ranging from tap water to industrial liquids. They employ standard vertical motors and quick-release mechanical seals, making replacement very convenient. They achieve intake, compression, and exhaust through the rotation of the impeller. Due to the very high water pressure inside vertical multistage pumps, water leakage often occurs at the connection between the motor and the pump casing.

[0003] Chinese Patent Publication No. CN110185626A, published on July 9, 2019, entitled "A Vertical Cylindrical Multistage Pump," improves the sealing effect between the motor and the pump barrel by setting a mechanical seal in the sealing cavity. However, due to the high cost of mechanical seals, many vertical multistage pumps still use sealing seats for sealing, which has poor sealing effect. Therefore, in order to further improve the sealing performance between the motor and the pump barrel, there is an urgent need for a high-sealing vertical stamping multistage pump that can still have a good sealing effect when the mechanical seal fails during use, and can effectively prevent internal liquid leakage caused by mechanical seal failure. Summary of the Invention

[0004] This invention overcomes the shortcomings of existing vertical multistage pumps where leakage easily occurs between the pump barrel and motor once the mechanical seal fails, due to the mechanical seal being used for sealing between the motor and the pump barrel. It provides a high-sealing vertical stamping multistage pump that can improve the sealing effect between the pump shaft and the pump barrel through the pressure of its own liquid, effectively preventing leakage of internal liquid due to mechanical seal failure.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a high-sealing vertical stamping multi-stage pump, comprising a pump barrel, with a motor installed at the top of the pump barrel, including: The high-pressure water pipe is connected at one end to the high-pressure outlet of the vertical multistage pump and at the other end to the water intake channel. The pump shaft is connected to the output end of the motor. A sealing seat is provided at the top of the pump barrel, and the pump shaft passes through the sealing seat. A cavity is provided at the corresponding position of the sealing seat and the pump shaft, and a high-pressure water pipe is connected to the cavity. A through hole is provided on the sealing seat, which is connected to the cavity, and the pump shaft passes through the through hole. A large annular groove is provided on the side wall of the cavity, and an air bladder is embedded in the large annular groove. A small annular groove is provided on the side wall of the through hole, and a sealing ring is provided in the small annular groove. The sealing ring is hollow and made of elastic material. An air passage is provided in the sealing seat, and the two ends of the air passage connect the air bladder and the hollow part of the sealing ring.

[0006] In this invention, high-pressure water flows into the cavity through a high-pressure water pipe. To improve the sealing effect between the sealing seat and the pump shaft, an air bladder is installed in the large annular groove. When the pressure inside the cavity increases due to the high-pressure water, the increased pressure acts on the air bladder, causing it to compress. The compressed air bladder then forces gas into the sealing ring through the air passage, causing the sealing ring to expand. The expanded sealing ring then abuts more tightly against the sealing ring groove on the side wall of the pump shaft, thereby improving the sealing effect between the sealing seat and the pump shaft. Simultaneously, the sealing ring can adjust the sealing force according to the internal water pressure, effectively preventing leakage of internal liquid due to mechanical seal failure, resulting in a better sealing effect.

[0007] Preferably, a first-stage impeller is provided at the bottom of the pump shaft; an axially oriented water inlet channel is provided at the center of the pump shaft, and a water outlet is provided in the circumferential direction of the side wall of the water inlet channel, which corresponds to the water inlet end of the first-stage impeller; and a water inlet is provided on the pump shaft to connect the cavity and the water inlet channel.

[0008] High-pressure liquid is introduced into the water intake channel from the inlet at the top of the pump shaft via a high-pressure water pipe, and then ejected from the outlet at the bottom of the pump shaft. This increases the local pressure in the low-pressure zone at the inlet of the first-stage impeller, preventing bubble formation and thus improving the impeller's cavitation resistance. In the event of significant cavitation, high-pressure water is supplied to the inlet end of the impeller, which also helps to reduce noise and vibration. Furthermore, since the high-pressure water is generated by the vertical multistage pump itself, no additional structure is needed to achieve the cavitation prevention effect.

[0009] Preferably, the sealing seat is provided with mounting ring grooves at both ends along the axial direction of the pump shaft, and a lip seal is provided in the mounting ring groove.

[0010] Lip seals can improve the sealing performance between the seal seat and the pump shaft.

[0011] As a preferred embodiment, the first-stage impeller is provided with several blades, and the number and position of the water outlet holes correspond to the number and position of the blades.

[0012] As the pump shaft drives the impeller to rotate, the relative position of the water outlet and the impeller remains unchanged. The high-pressure water spray increases the pressure in the water area where the corresponding blade is prone to cavitation, thereby protecting the blade inlet from cavitation and increasing the product's service life.

[0013] As a preferred option, the water flow rate of both the blades and the water outlet is set to 4.

[0014] Setting four water outlets ensures that the blades can provide power while also guaranteeing the strength of the pump shaft.

[0015] Preferably, the side wall of the pump shaft in the circumferential direction is provided with a sealing ring groove corresponding to the position of the small annular groove, and the sealing ring abuts against the sealing ring groove.

[0016] The sealing ring abuts against the sealing ring groove, which enables a better sealing effect.

[0017] Preferably, the sealing seat is provided with mounting ring grooves at both the upper and lower ends along the axial direction of the pump shaft, and a lip seal is provided in the mounting ring groove. The mounting ring groove at the upper end, the lip seal, the side wall of the pump shaft and the sealing ring form a sealed cavity, and lubricating oil is provided in the sealed cavity.

[0018] As the pressure in the cavity changes, the sealing ring expands and contracts accordingly. Lubricating oil is placed in the sealed cavity, so that the lubricating oil is squeezed between the sealing ring and the sealing ring groove during the expansion and contraction of the sealing ring, thereby ensuring the lubrication effect between the sealing ring groove and the sealing ring.

[0019] Preferably, the sealing ring is made of rubber.

[0020] Compared with the prior art, the beneficial effects of the present invention are: (1) The force exerted on the airbag by the cavity causes the sealing ring to expand, which improves the sealing performance between the sealing seat and the pump shaft; (2) High-pressure water from the high-pressure outlet is introduced into the inlet of the first impeller through a high-pressure water pipe, which can effectively prevent cavitation of the first turbine and improve the service life of the product. Since the high-pressure water is generated by the vertical multistage pump itself, no other structure is needed to achieve the anti-cavitation effect, thus reducing production costs. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of the internal structure of the present invention; Figure 2 yes Figure 1 A magnified view of a portion of region A in the middle; Figure 3 yes Figure 1 A magnified view of a portion of region B in the middle; In the diagram: 1. Pump barrel, 11. High-pressure outlet, 12. Pump base; 2. Electric motor; 3. Pump shaft; 31. Water inlet channel; 32. Water outlet; 33. Water inlet; 34. Sealing ring groove; 4. First stage impeller; 41. Blades; 5. High-pressure water pipe; 6. Sealing seat; 61. Cavity; 611. Large annular groove; 62. Mounting annular groove; 621. Lip seal; 63. Perforation; 631. Small annular groove; 64. Air passage. 7. Airbag; 71. Sealing ring. Detailed Implementation

[0022] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Example 1: Refer to Figures 1 to 3 As shown, a high-sealing vertical stamping multistage pump includes a pump barrel 1, a motor 2 mounted on the top of the pump barrel 1, and a pump base 12 fixedly mounted on the bottom of the pump barrel 1. A low-pressure inlet and a high-pressure outlet 11 are respectively provided on both sides of the pump base 12. A pump shaft 3 is installed inside the pump cylinder 1. The upper end of the pump shaft 3 is connected to the output end of the motor 1, and the lower end of the pump shaft 3 is rotatably connected to the pump base 12. Several impellers are arranged on the pump shaft 3 along its length, among which the first-stage impeller 4 is arranged at the bottom of the pump shaft 3. One end of the high-pressure water pipe 5 is connected to the high-pressure outlet 11 of the vertical multistage pump, and the other end of the high-pressure water pipe 5 is connected to the cavity 61 at the upper end of the pump shaft 3.

[0023] A sealing seat 6 is provided between the top of the pump cylinder 1 and the motor 2. The pump shaft 3 passes through the sealing seat 6. A cavity 61 is provided at the corresponding position of the sealing seat 6 and the pump shaft 3. The high-pressure water pipe 5 is connected to the cavity 61. A through hole 63 is provided on the sealing seat 6, which communicates with the cavity 61. The pump shaft 3 passes through the through hole 63. A large annular groove 611 is provided on the side wall of the cavity 61. An air bladder 7 is embedded in the large annular groove 611. A small annular groove 631 is provided on the side wall of the through hole 63. A sealing ring 71 is provided in the small annular groove 631. The sealing ring 71 is hollow and is made of elastic material. In this embodiment, the sealing ring 71 is made of rubber material. An air passage 64 is provided in the sealing seat 6. The two ends of the air passage 64 are connected to the hollow part of the air bladder 7 and the sealing ring 71.

[0024] The side wall of the pump shaft 3 in the circumferential direction is provided with a sealing ring groove 34 corresponding to the position of the small annular groove 631, and the sealing ring 71 abuts against the sealing ring groove 34.

[0025] The sealing seat 6 has mounting ring grooves 62 at both ends along the axial direction of the pump shaft 3. A lip seal 621 is provided in the mounting ring groove 62. The mounting ring groove 62, the lip seal 621, the side wall of the pump shaft 3 and the sealing ring 71 form a sealed cavity, and lubricating oil is provided in the sealed cavity.

[0026] The sealing seat 6 has mounting ring grooves 62 at both ends along the axial direction of the pump shaft 3, and a lip seal ring 621 is provided in the mounting ring groove 62.

[0027] The working principle of this embodiment is as follows: As high-pressure water flows into the cavity 61 from the high-pressure water pipe 5, in order to improve the sealing effect between the sealing seat 6 and the pump shaft 3, an air bladder 7 is set in the large annular groove 611. When the pressure inside the cavity 61 increases due to the action of high-pressure water, the increased pressure acts on the air bladder 7, causing the air bladder 7 to be compressed. The compressed air bladder 7 forces gas into the sealing ring 71 through the air passage 64, causing the sealing ring 71 to expand. The expanded sealing ring 71 abuts more tightly with the sealing ring groove 34 on the side wall of the pump shaft 3, thereby improving the sealing effect between the sealing seat 6 and the pump shaft 3. The expansion effect of the sealing ring 71 is related to the pressure inside the cavity 61. As the water pressure inside the cavity 61 changes, the pressure inside the sealing ring 71 also changes. When the pressure inside the cavity 61 decreases, the sealing ring 71 expands less, reducing wear between the sealing ring 71 and the sealing ring groove 34 and improving the service life of the sealing ring 71. When the pressure inside the cavity 61 increases, the expansion of the sealing ring 71 increases, allowing the sealing ring 71 to fit tightly against the sealing ring groove 34 of the pump shaft 3, thus improving the sealing performance between the sealing seat 6 and the pump shaft 3.

[0028] Example 2: Refer to Figures 1 to 3 As shown, the structure of this embodiment 1 is similar, except that the sealing seat 6 is provided with mounting ring grooves 62 at both ends along the axial direction of the pump shaft 3, and a lip seal ring 621 is provided in the mounting ring groove 62. The mounting ring groove 62, the lip seal ring 621, the side wall of the pump shaft 3 and the sealing ring 71 form a sealed cavity, and lubricating oil is provided in the sealed cavity.

[0029] In this embodiment, as the pressure in the cavity 61 changes, the sealing ring 71 expands and contracts with the pressure change in the cavity 61. Lubricating oil is provided in the sealed cavity, so that the lubricating oil is squeezed between the sealing ring 71 and the sealing ring groove 34 during the expansion and contraction of the sealing ring 71, thereby ensuring the lubrication effect between the sealing ring groove 34 and the sealing ring 71.

[0030] Example 3: Reference Figures 1 to 3 As shown, this embodiment is similar in structure to embodiment 1 or embodiment 2, except that the pump shaft 3 has a water inlet channel 31 arranged axially at its center, and the pump shaft 3 has a water inlet hole 33 that connects the cavity 61 and the water inlet channel 31.

[0031] A water outlet 32 ​​is provided circumferentially on the side wall of the water inlet channel 31, corresponding to the water inlet side of the first-stage impeller 4. The first-stage impeller 4 has several blades 41, and the number and position of the water outlet 32 ​​correspond to the number and position of the blades 41. In this embodiment, to ensure the strength of the pump shaft 3, four blades 41 and four water outlets 32 are provided. To improve the anti-cavitation effect, the water sprayed from the water outlet 32 ​​contacts the blades 4 tangentially.

[0032] Cavitation refers to the process where the absolute pressure of the liquid in a localized area of ​​the pump's flow path is lower than the vaporization pressure, causing vaporization and the formation of bubbles. These bubbles then enter the high-pressure zone, burst, and condense, damaging the flow path components. The back of the impeller blades is a low-pressure area, and bubbles typically form slightly behind the blade inlet. Therefore, to fundamentally improve cavitation performance, it is essential to prevent bubble formation at the impeller inlet. In this embodiment, to prevent cavitation of the first-stage impeller 4, high-pressure water from the high-pressure outlet of the pump base 7 is diverted to the upper end of the pump shaft 3 via the high-pressure water pipe 5. The high-pressure water reaches the cavity 61 of the sealing seat 6, and then flows into the water channel 31 through the inlet hole 33. After passing through, it reaches the outlet hole 32 and is sprayed out from the outlet hole 32. The position and number of outlet holes 32 correspond to the position and number of blades 41. When the pump shaft 3 drives the impeller 41 to rotate, the relative position of the outlet hole 32 and the impeller 4 remains unchanged. The high-pressure water spray increases the pressure in the water area of ​​the blade 41 where cavitation is likely to occur, thereby protecting the blade inlet from cavitation and increasing the service life of the product.

[0033] In this embodiment, a pressurized liquid is introduced into the water intake channel 31 from the inlet 33 at the upper end of the pump shaft 3 via a high-pressure water pipe 5, and then ejected from the outlet 32 ​​at the lower end of the pump shaft 3. This increases the local pressure in the low-pressure zone at the inlet of the first-stage impeller 4, preventing bubble formation and thus improving the impeller 4's cavitation resistance. When significant cavitation occurs, supplying high-pressure water to the inlet end of the impeller 4 also helps to reduce noise and vibration. Furthermore, since the high-pressure water is generated by the vertical multistage pump itself, no additional structure is needed to achieve the cavitation prevention effect.

[0034] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications may be made without departing from the technical solutions described in the claims.

Claims

1. A high-sealing vertical stamping multistage pump, comprising a pump barrel, wherein a motor is disposed at the top of the pump barrel, characterized in that, include: The high-pressure water pipe is connected at one end to the high-pressure outlet of the vertical multistage pump and at the other end to the water intake channel. The pump shaft is connected to the output end of the motor. A sealing seat is provided at the top of the pump barrel, and the pump shaft passes through the sealing seat. A cavity is provided at the corresponding position of the sealing seat and the pump shaft, and a high-pressure water pipe is connected to the cavity. A through hole is provided on the sealing seat, which is connected to the cavity, and the pump shaft passes through the through hole. A large annular groove is provided on the side wall of the cavity, and an air bladder is embedded in the large annular groove. A small annular groove is provided on the side wall of the through hole, and a sealing ring is provided in the small annular groove. The sealing ring is hollow and made of elastic material. An air passage is provided in the sealing seat, and the two ends of the air passage connect the air bladder and the hollow part of the sealing ring. When the pressure inside the cavity increases due to the action of high-pressure water, the increased pressure acts on the air bladder, causing the air bladder to be compressed. The compressed air bladder forces gas into the sealing ring through the air passage, causing the sealing ring to expand. The expanded sealing ring abuts more tightly against the sealing ring groove on the side wall of the pump shaft. At the same time, the sealing ring can adjust the sealing force according to the internal water pressure, which can effectively prevent internal liquid leakage due to mechanical seal failure.

2. The high-sealing vertical stamping multistage pump according to claim 1, characterized in that, The pump shaft has a first-stage impeller at its bottom; a water inlet channel is located at the center of the pump shaft along the axial direction, and a water outlet is located on the circumferential direction of the side wall of the water inlet channel, which corresponds to the water inlet end of the first-stage impeller; and a water inlet is located on the pump shaft that connects the cavity and the water inlet channel.

3. The high-sealing vertical stamping multistage pump according to claim 1, characterized in that, The sealing seat has mounting ring grooves at both ends along the axial direction of the pump shaft, and a lip seal ring is installed in the mounting ring groove.

4. The high-sealing vertical stamping multistage pump according to claim 1 or 2, characterized in that, The first-stage impeller has several blades, and the number and position of the water outlet holes correspond to the number and position of the blades.

5. The high-sealing vertical stamping multistage pump according to claim 4, characterized in that, The water flow rate of both the blades and the water outlet is set to 4.

6. The high-sealing vertical stamping multistage pump according to any one of claims 1 to 3, characterized in that, The side wall of the pump shaft in the circumferential direction is provided with a sealing ring groove corresponding to the position of the small annular groove, and the sealing ring abuts against the sealing ring groove.

7. The high-sealing vertical stamping multistage pump according to claim 6, characterized in that, The sealing seat has mounting ring grooves at both the upper and lower ends along the axial direction of the pump shaft. A lip seal is installed in the mounting ring groove. The mounting ring groove at the upper end, the lip seal, the side wall of the pump shaft and the sealing ring form a sealed cavity, which is filled with lubricating oil.

8. The high-sealing vertical stamping multistage pump according to any one of claims 1 to 3, characterized in that, The sealing ring is made of rubber.

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