CN219974895U - Annular tube type axial flow pump for high cavitation occasion - Google Patents

Abstract

The utility model belongs to the technical field of centrifugal pumps, and particularly relates to a ring pipe type axial flow pump for a high cavitation occasion. The utility model comprises a pump body with an arc-shaped appearance, wherein a pump cavity for medium passing is formed by a pump body cavity; the pump shaft penetrates through the outer wall of the pump body and then extends to the inlet of the pump body, and an impeller is coaxially arranged at the shaft end of the pump shaft, which is positioned in the pump cavity; the feeding direction of the medium is taken as the front of the impeller, an inducer is coaxially fixed on a pump shaft in front of the impeller, a guide vane is rotatably matched on the pump shaft behind the impeller, and the guide vane is fixed at a pump cavity; along the running direction of the medium, the number of the inducer, the impeller and the blades of the guide vane are sequentially increased, the outlet blades of the inducer and the inlet blades of the impeller are staggered, and the outlet blades of the impeller and the inlet blades of the guide vane are staggered. The utility model can effectively improve the phenomena of noise, vibration, corrosion damage of the overcurrent component and unstable working performance caused by cavitation, ensure the stability and reliability of the pump during working and ensure the service life of the pump.

Description

Annular tube type axial flow pump for high cavitation occasion

Technical Field

The utility model belongs to the technical field of centrifugal pumps, and particularly relates to a ring pipe type axial flow pump for a high cavitation occasion.

Background

The annular pipe axial flow pump is core equipment of devices such as polypropylene, polyethylene and the like, and has the function of providing circulating power for the whole reaction device; the equipment needs to be stably operated for a long time, and the good working performance of the annular pipe axial flow pump is one of key factors. At present, as the design height of the annular pipe axial flow pump is influenced by the limiting condition, the following problems are easy to occur under the use condition of high cavitation requirement: first, when the pump is cavitation, the bubbles break after being continuously generated in the high pressure area and the accompanying strong water hammer can generate great noise and vibration to influence the surrounding environment. Secondly, during cavitation, the metal surface is impacted by high frequency above 600Hz when bubbles are condensed, so that metal grains on the metal surface are loosened and peeled off; cavitation damage is accompanied by various complex actions such as electrolysis and chemical corrosion besides the action of mechanical force, thereby greatly influencing the service life of the traditional axial flow pump. Thirdly, when the pump is cavitation, the energy exchange of the liquid in the impeller is disturbed and destroyed, and the performance of the pump is unstable and reduced. Later, the method of improving cavitation by forcibly increasing the height of the ring pipe is also carried out, but a series of linkage problems such as high price, large occupied space, inconvenient disassembly and assembly, complex structure, long operation and manufacturing period and the like exist, and the problem needs to be solved.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art and provide a ring-tube type axial flow pump for high cavitation occasions, which can effectively improve the phenomena of noise, vibration, corrosion damage of an overflow component and unstable working performance caused by cavitation, thereby ensuring the stability and the reliability of the pump during working and ensuring the service life of the pump.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

a ring pipe type axial flow pump for high cavitation occasion comprises a pump body with an arc-shaped appearance, wherein a pump cavity for medium passing is formed by a pump body cavity; the pump shaft penetrates through the outer wall of the pump body and then extends to the inlet of the pump body, and an impeller is coaxially arranged at the shaft end of the pump shaft, which is positioned in the pump cavity; the method is characterized in that: the feeding direction of the medium is taken as the front of the impeller, an inducer is coaxially fixed on a pump shaft in front of the impeller, a guide vane is rotatably matched on the pump shaft behind the impeller, and the guide vane is fixed at a pump cavity; along the medium advancing direction, the number of the inducer, the impeller and the blades of the guide vane are sequentially increased, the outlet blades of the inducer and the inlet blades of the impeller are staggered, and the outlet blades of the impeller and the inlet blades of the guide vane are staggered.

Preferably, the inducer and the impeller are assembled on the pump shaft through key connection, and the lock nut is arranged at the front end of the pump shaft, so that the inducer and the impeller are clamped through the fit between the lock nut and the front end face of the guide vane.

Preferably, the tube cavity of the guide vane extends horizontally to the outer wall of the pump body along the axial direction of the guide vane, so that the tube cavity forms a passing cavity for the pump shaft to pass through; the guide vane tube cavity is internally provided with a front bearing, and the frame at the outer wall of the pump body is provided with a rear bearing, so that the pump shaft simply supported beam type rotary fit is realized at the pump body and the frame.

Preferably, the pass-through lumen extends into the housing; a main mechanical seal is arranged at the head end of the passing cavity where the front bearing is positioned, and a safety mechanical seal is arranged at the tail end of the passing cavity in front of the rear bearing; the lubricating liquid enters the passing cavity through the liquid inlet at the guide vane, and is discharged through the liquid outlet after passing through the gaps among the front bearing, the pump shaft and the passing cavity and the safety mechanical seal in sequence.

Preferably, the frame comprises a bearing housing for mounting the rear bearing and a connecting frame for connecting the bearing housing and the pump body, the safety mechanical seal is positioned in the connecting frame, and the connecting frame and the bearing housing are isolated from each other.

Preferably, lubricating oil is poured into the bearing box, and a water cooling cavity with a cooling function is arranged at the outer wall of the bearing box.

Preferably, shaft oil seals for preventing lubricating liquid from leaking outside are arranged at two ends of the bearing box, which can be penetrated by the pump shaft.

The utility model has the beneficial effects that:

according to the scheme, the inducer can improve the pressure of the pump inlet, so that the cavitation performance of the centrifugal pump is improved, and meanwhile, the centrifugal force for promoting the separation of bubbles and liquid does not exist, so that the generated bubbles flow away along with the liquid, and the blockage of the whole flow passage is not easy to cause; the inducer can work under the cavitation working condition, and effectively reduces the conditions of noise, vibration, corrosion damage of an overflow part, unstable performance and the like caused by pump cavitation. In addition, along the medium advancing direction, the number of the inducer, the impeller and the blades of the guide vane are sequentially increased, the outlet blades of the inducer and the inlet blades of the impeller are staggered, the outlet blades of the impeller and the inlet blades of the guide vane are staggered, the same-frequency resonance problem possibly generated when the medium enters the guide vane after acting through the inducer and the impeller can be effectively avoided, the stability and the reliability of the pump during working are further improved finally, and the service life of the pump is ensured.

Drawings

FIG. 1 is a cross-sectional view of the structure of the present utility model;

fig. 2 is a partial enlarged view of the portion I of fig. 1.

The actual correspondence between each label and the component name of the utility model is as follows:

10-a pump body; 20-pump shaft; 21-front bearing; 22-rear bearings; 30-impeller;

40-inducer; 50-guide vanes; 51-pass through lumen; 60-locking nut;

71-main mechanical seal; 72-a safety mechanical seal; 81-a liquid inlet; 82-a liquid outlet;

91-bearing housing; 92-connecting frames; 93-a water cooling cavity; 94-shaft oil seal.

Detailed Description

For ease of understanding, the specific structure and operation of the present utility model will be further described herein with reference to FIGS. 1-2:

as shown in FIG. 1, the utility model comprises a pump body 10 with a pump cavity, and a pump shaft 20 is penetrated in the pump body 10. Along the axial direction of the pump shaft 20, a lock nut 60, an inducer 40, an impeller 30, a guide vane 50, a main engine seal 71, a front bearing 21, a safety mechanical seal 72, a connecting frame 92, a bearing housing 91 with a shaft oil seal 94, and a rear bearing 22 are sequentially arranged.

In actual assembly, as shown in FIG. 1, the vane 50 is welded within the pump cavity, and the lumen of the vane 50 extends horizontally through the pump body 10 to form a pass through cavity 51. The pump shaft 20 passes through the passing cavity 51 and then extends into the pump cavity from the outside of the pump body 10, the inducer 40 is arranged at the forefront end of the pump shaft 20, and the inducer 40 can be driven to rotate along with the pump shaft 20 through a front connecting key. The impeller 30 is arranged at the rear part of the inducer 40, the number of the inducer 40 blades is smaller than that of the impeller 30, and the outlet blades of the inducer 40 are staggered with the inlet blades of the impeller 30 by a certain angle; in this way, when the impeller 30 and the inducer 40 rotate together and drive the medium to enter the impeller 30 after the medium passes through the inducer 40 from the inlet to do work, the same-frequency resonance phenomenon of the medium can be avoided, and the performance of the device is affected. The rear connecting key drives the impeller 30 to rotate along with the pump shaft 20, and the inducer 40 and the impeller 30 are locked by means of the threaded fit of the locking nut 60 and the front end of the pump shaft 20, and the guide vane 50 is arranged at the rear part of the outlet of the impeller 30. Likewise, the impeller 30 has fewer blades than the guide vanes 50, and the impeller 30 outlet blades are staggered from the guide vanes 50 inlet blades by a certain angle; in this way, when the impeller 30 and the inducer 40 rotate together and drive the medium to enter the guide vane 50 after the medium passes through the impeller 30 from the inlet to do work, the same frequency resonance phenomenon of the medium can be avoided, and the performance of the device is affected. In actual design, as previously described, the vane 50 is welded to the pump cavity so as to be integral with the pump body 10.

Further, a main mechanical seal 71 is mounted within the hub cavity, i.e. the lumen, of the vane 50. As shown in fig. 2, the main mechanical seal 71 contains the front bearing 21. The front bearing 21 and the rear bearing 22 form two-point contact, and form two-point support when the pump is running, so that the pump runs more stably. The safety mechanical seal 72 is mounted in a frame at the rear of the pump body 10, mainly for sealing during operation of the pump. The frame comprises a connection frame 92 and a bearing housing 91. In the concrete assembly, the connecting frame 92 is installed outside the pump body 10, the bearing housing 91 is installed at the rear part of the connecting frame 92 through bolt connection, the safety mechanical seal 72 capable of blocking the tail end of the passing cavity 51 is placed in the connecting frame 92, and the rear bearing 22 is installed in the bearing housing 91.

In actual lubrication, lubricating oil or lubricating fluid with certain pressure is filled into the lubricating inlet flange, namely the liquid inlet 81, through mechanical seal flushing. The lubricating oil then enters the main mechanical seal 71 through the preset radial flushing holes in the guide vane 50, and the main mechanical seal 71 and the front bearing 21 generate a great amount of heat through friction and rotation of the dynamic and static components under the operation condition, and the lubricating oil is lubricated and cooled by the lubricating oil. Through the gap between the pump shaft 20 and the passing cavity 51, lubricating oil can continue to flow to the position of the safety mechanical seal 72, so that lubricating and cooling of the safety mechanical seal 72 are realized. Finally, the lubricating oil flows out through the mechanical seal flushing lubricating outlet flange, namely the liquid outlet 82, and the process is circulated continuously, so that a large amount of heat generated by friction and rotation of the dynamic and static parts is taken away, and simultaneously, the main mechanical seal 71, the front bearing 21 and the safety mechanical seal 72 are lubricated, and the dynamic and static friction coefficient is reduced.

As shown in fig. 1, the bearing housing 91 includes a water cooling chamber 93, and cooling water flowing through the water cooling chamber 93 cools the lubricating oil in the bearing housing 91 that surrounds the rear bearing 22. Shaft seals 94 are installed at the front and rear sides of the bearing housing 91 for preventing leakage of lubricating oil in the bearing housing 91.

The utility model aims at the polypropylene axial flow pump or the polyethylene axial flow pump with complex structure and strict requirements, and can effectively improve the conditions of noise, vibration, corrosion damage of an overcurrent component, unstable performance and the like caused by insufficient height of a ring pipe and cavitation. Meanwhile, the special design between the impeller 30 and the inducer 40 and between the impeller 30 and the guide vane 50 can eliminate the influence of the same-frequency resonance on the pump performance. In addition, the double-point support is generated between the front bearing 21 and the rear bearing 22 which are double-row angular contact bearings in the main mechanical seal 71, so that the pump shaft 20 can be effectively supported, the cantilever ratio between the impeller 30 and the front span is further reduced, and the impeller 30 is more stable and reliable in operation. The front bearing 21 and the rear bearing 22 are respectively provided with a corresponding self-lubricating cooling system, so that the working reliability is higher. Finally, when the pump is inspected and maintained or the pump is required to be disassembled, the impeller 30 and the inducer 40 can be disassembled after the lock nut 60 is disassembled, and the pump shaft 20, the bearing box 91 and the like can be pulled out from the driving end so as to be convenient for the maintenance and the repair operation, and the disassembly and the assembly are very convenient.

It will be understood by those skilled in the art that the present utility model is not limited to the details of the foregoing exemplary embodiments, but includes other specific forms of the same or similar structures that may be embodied without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the utility model being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.

The technology, shape, and construction parts of the present utility model, which are not described in detail, are known in the art.

Claims (7)

1. A ring-tube type axial flow pump for high cavitation occasions comprises a pump body (10) with an arc-shaped appearance, wherein a pump cavity for medium passing is formed by a tube cavity of the pump body (10); the pump shaft (20) penetrates through the outer wall of the pump body (10) and then extends to the inlet of the pump body (10), and an impeller (30) is coaxially arranged at the shaft end of the pump shaft (20) positioned in the pump cavity; the method is characterized in that: the feeding direction of a medium is taken as the front of an impeller (30), an inducer (40) is coaxially fixed on a pump shaft (20) in front of the impeller (30), a guide vane (50) is rotatably matched on the pump shaft (20) behind the impeller (30), and the guide vane (50) is fixed at a pump cavity; along the medium advancing direction, the number of the blades of the inducer (40), the impeller (30) and the guide vane (50) is increased in sequence, the outlet blades of the inducer (40) and the inlet blades of the impeller (30) are staggered, and the outlet blades of the impeller (30) and the inlet blades of the guide vane (50) are staggered.

2. A grommet axial flow pump for high cavitation applications as set forth in claim 1, wherein: the inducer (40) and the impeller (30) are assembled on the pump shaft (20) through key connection, and a lock nut (60) is arranged at the front end of the pump shaft (20), so that the inducer (40) and the impeller (30) are clamped through the cooperation between the lock nut (60) and the front end face of the guide vane (50).

3. A grommet axial flow pump for use in high cavitation applications according to claim 1 or 2, wherein: the tube cavity of the guide vane (50) horizontally extends to the outer wall of the pump body (10) along the axial direction of the guide vane (50), so that the tube cavity forms a passing cavity (51) for the pump shaft (20) to pass through; a front bearing (21) is arranged in a pipe cavity of the guide vane (50), and a rear bearing (22) is arranged at a frame at the outer wall of the pump body (10), so that the pump shaft (20) is in simple beam type rotary fit at the pump body (10) and the frame.

4. A grommet axial flow pump for use in high cavitation applications as set forth in claim 3, wherein: the passing cavity (51) extends into the frame; a main mechanical seal (71) is arranged at the head end of the passing cavity (51) where the front bearing (21) is positioned, and a safety mechanical seal (72) is arranged at the tail end of the passing cavity (51) in front of the rear bearing (22); lubricating liquid enters the passing cavity (51) through a liquid inlet (81) at the guide vane (50), and is discharged through a liquid outlet (82) after passing through a front bearing (21), a gap between the pump shaft (20) and the passing cavity (51) and a safety mechanical seal (72) in sequence.

5. A grommet axial flow pump for use in high cavitation applications as set forth in claim 4, wherein: the frame comprises a bearing box (91) for mounting the rear bearing (22) and a connecting frame (92) for connecting the bearing box (91) with the pump body (10), the safety mechanical seal (72) is positioned in the connecting frame (92), and the connecting frame (92) and the bearing box (91) are isolated from each other.

6. A grommet axial flow pump for use in high cavitation applications as set forth in claim 5, wherein: lubricating oil is poured into the bearing box (91), and a water cooling cavity (93) with a cooling function is arranged at the outer wall of the bearing box (91).

7. A grommet axial flow pump for use in high cavitation applications as set forth in claim 6, wherein: shaft oil seals (94) which can prevent lubricating liquid from leaking outwards are arranged at two ends of the bearing box (91) through which the pump shaft (20) passes.