CN115013350A

CN115013350A - Self-adaptive axial force balance auxiliary device for leakage-free centrifugal pump

Info

Publication number: CN115013350A
Application number: CN202210824432.9A
Authority: CN
Inventors: 张玉良; 李立民; 陈波; 卢新海
Original assignee: Lihuayi Weiyuan Chemical Co ltd
Current assignee: Lihuayi Weiyuan Chemical Co ltd
Priority date: 2022-07-13
Filing date: 2022-07-13
Publication date: 2022-09-06

Abstract

The invention relates to the technical field of centrifugal pumps, and discloses a self-adaptive axial force balance auxiliary device for a leakage-free centrifugal pump, which is arranged between an impeller and a pump cover of the leakage-free centrifugal pump and comprises a wear-resisting ring and a balance throttling ring, wherein the center of the wear-resisting ring is sleeved with a centrifugal pump shaft, the wear-resisting ring is connected with the impeller through a first countersunk head bolt, the balance throttling ring is positioned on the right side of the wear-resisting ring, the center of the balance throttling ring is sleeved with the centrifugal pump shaft, the pump cover is provided with an annular groove, the wear-resisting ring and the balance throttling ring are both embedded into the annular groove, and the balance throttling ring is fixed on the pump cover through a second countersunk head bolt. The invention has simple structure, low manufacturing cost and good balancing effect, can ensure that the circulating liquid in the non-leakage centrifugal pump works under the allowable minimum internal reflux amount, and reduces the internal reflux of the pump. Therefore, the potential faults of the leakage-free centrifugal pump are reduced, and the working efficiency of the centrifugal pump is improved.

Description

Self-adaptive axial force balance auxiliary device for leakage-free centrifugal pump

Technical Field

The invention relates to the technical field of centrifugal pumps, in particular to a self-adaptive axial force balance auxiliary device for a leakage-free centrifugal pump.

Background

The axial force balance system of the existing non-leakage centrifugal pump, such as a canned motor pump, a magnetic pump and the like, generally adopts the schemes of opening balance holes on an impeller, additionally installing balance wheels, using balance bearings, symmetrically arranging the impeller or combining the schemes and the like. Although the axial force balance scheme of the centrifugal pump is mature, the defects that the anti-cavitation (evacuation) capability is poor, the internal reflux quantity of the pump is large, the working efficiency is influenced, the equipment state is greatly influenced by the flow and the like exist all the time, and once the flow instability working condition is met, the sliding bearing and the thrust bearing of the equipment can be broken under the action of huge axial force and vibration in a short time, so that the equipment is seriously damaged, and the maintenance cost is greatly increased.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide an adaptive axial force balance auxiliary device for a leakage-free centrifugal pump.

In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides a balanced auxiliary device of self-adaptation axial force for no leakage centrifugal pump, sets up between the impeller of no leakage centrifugal pump and pump cover, its characterized in that: including wear-resisting ring and balanced throttle ring, the centrifugal pump shaft is cup jointed at the wear-resisting ring center, wear-resisting ring is through first countersunk head bolted connection impeller, the wear-resisting ring left side is equipped with the draw-in groove, impeller bottom surface joint draw-in groove, be equipped with the water conservancy diversion hole on the wear-resisting ring, the water conservancy diversion hole link up with the balancing hole of impeller, balanced throttle ring is located the wear-resisting ring right side, centrifugal pump shaft is cup jointed at balanced throttle ring center, the pump cover is equipped with the annular groove, wear-resisting ring and balanced throttle ring all imbed in the annular groove, balanced throttle ring passes through second countersunk head bolted connection on the pump cover, the clearance between wear-resisting ring and the balanced throttle ring is less than 0.05 mm.

Further, the method comprises the following steps of; and a plurality of annular throttling grooves are formed in one side, close to the wear-resistant ring, of the balance throttling ring.

Further, the method comprises the following steps of; and a first sealing gasket is arranged between the wear-resistant ring and the bottom surface of the impeller, and a through hole communicated with the balance hole is formed in the first sealing gasket.

Further, the method comprises the following steps of; and a second sealing gasket is arranged between the balance throttling ring and the bottom of the annular groove.

The invention has the beneficial effects that:

the invention has simple structure, low manufacturing cost and good balancing effect, can ensure that the circulating liquid in the non-leakage centrifugal pump works under the allowable minimum internal reflux amount, and reduces the internal reflux of the pump. Therefore, the potential faults of the leakage-free centrifugal pump are reduced, and the working efficiency of the centrifugal pump is improved.

In the process of balancing the axial force, the axial movement of the impeller can be smaller than 0.2mm, and the axial displacement of the conventional non-leakage centrifugal pump can reach about 2mm, so that the axial displacement phenomenon of the non-leakage centrifugal pump during cavitation or evacuation can be greatly reduced, the cavitation or evacuation resistance of the non-leakage centrifugal pump is improved, and the operation of the non-leakage centrifugal pump is effectively protected.

The invention is convenient to install and use, can be installed when the centrifugal pump is manufactured, can be additionally installed after the centrifugal pump is finished, and can be used as a compensatory repair of a maintenance part even after the centrifugal pump is slightly damaged so as to achieve longer equipment operation period.

Drawings

FIG. 1 is an exploded view of the present invention;

FIG. 2 is a schematic view of the assembled structure of the present invention;

FIG. 3 is a schematic view of a balanced throttle ring configuration.

In the figure: 1. a balance hole; 2. an impeller front cover plate; 3. an impeller rear cover plate; 4. the impeller balance throttle ring; 5. a first sealing gasket; 6. a wear ring; 7. a first countersunk bolt; 8. a balance throttle ring; 9. a balance seal ring groove; 10. a pump cover; 11. an impeller; 12. a cover plate of the impeller balance cavity; 13. a balancing chamber; 14. a second sealing gasket; 15. a second countersunk bolt; 16. a flow guide hole; 17. a card slot; 18. an annular groove; 19. a pump shaft; 20. an annular throttling groove.

Detailed Description

Example (b):

as shown in fig. 1 and fig. 3, an adaptive axial force balance assisting device for a non-leakage centrifugal pump is arranged between an impeller 11 and a pump cover 10 of the non-leakage centrifugal pump, and includes a wear-resistant ring 6 and a balance throttle ring 8, a centrifugal pump shaft 19 is sleeved in the center of the wear-resistant ring 6, the wear-resistant ring 6 is fixedly connected with the impeller 11 through a first countersunk head bolt 7 and rotates with the pump shaft 19, a clamping groove 17 is arranged on the left side of the wear-resistant ring 6, the clamping groove 17 is arranged on the bottom surface of the impeller 11, a flow guide hole 16 is arranged on the wear-resistant ring 6, the flow guide hole 16 is communicated with a balance hole 1 of the impeller 11, the balance throttle ring 8 is located on the right side of the wear-resistant ring 6, the pump shaft 19 is sleeved in the center of the balance throttle ring 8, the pump cover 10 is provided with an annular groove 18, the wear-resistant ring 6 and the balance throttle ring 8 are both embedded in the annular groove 18, the balance throttle ring 8 is fixed on the pump cover 10 through a second countersunk head bolt 15, the balance throttle ring 8 does not rotate along with the pump shaft 19, and the gap between the wear-resisting ring 6 and the balance throttle ring 8 is less than 0.05 mm.

In this embodiment, preferably, a first sealing gasket 5 is disposed between the wear-resistant ring 6 and the bottom surface of the impeller 11, a through hole penetrating through the balance hole 1 is disposed on the first sealing gasket 5, and the first countersunk head bolt 7 penetrates through the wear-resistant ring 6 and the first sealing gasket 5 to connect the impeller 11.

In this embodiment, a second sealing gasket 14 is preferably arranged between the balance throttle ring 8 and the bottom of the annular groove 18, and the second countersunk head bolt 15 penetrates through the pump cover 10 and the second sealing gasket 14 to connect the balance throttle ring 8.

In the present embodiment, the balance throttle ring 8 is preferably provided with a plurality of annular throttle grooves 20 on a side close to the wear-resistant ring 6.

Preferably, the wear-resistant ring 6 is made of a hard material, and the balance throttle ring 8 is made of a soft material.

The working principle is as follows: the invention is arranged between an impeller 11 and a pump cover 10, and an impeller balance sealing ring 4 is embedded into a balance sealing ring groove 9 on the pump cover 10 to form a throttling structure and form a balance cavity 13. Because a certain gap exists between the wear-resisting ring 6 and the balance throttling ring 8, the hardness of the processing materials of the wear-resisting ring 6 and the balance throttling ring 8 is different, and the annular throttling groove 20 on the annular surface of the balance throttling ring 8 is arranged, the collision and abrasion between the wear-resisting ring 6 and the balance throttling ring 8 can be reduced to the maximum extent.

Starting the centrifugal pump, eliminating other axial force conditions of the pump, and respectively applying three forces to the impeller 11, namely a force applied to the front cover plate 2 of the impeller and directed to the right side and a resultant force applied to the rear cover plate 3 of the impeller and the cover plate 12 of the balancing cavity of the impeller and directed to the left side. Because the pressure intensity of the front cover plate 2 of the impeller and the pressure intensity of the rear cover plate 3 of the impeller are the same in unit area, but because the stress area of the front cover plate 2 of the impeller is larger than that of the rear cover plate 3 of the impeller, the axial force of the impeller 11 is unbalanced, the impeller 11 has the tendency of moving to the right side, at the moment, high-pressure liquid flowing into the balance cavity 13 through the positions near the balance throttling ring 4 of the impeller and the groove 9 of the balance sealing ring and medium-pressure liquid flowing into a cooling system of the pump shaft 19 exist, and the flowing-in liquid can only flow into the balance hole 1 of the impeller through a gap between the balance throttling ring 8 and the wear-resisting ring 6 after being gathered and finally returns to the inlet of the impeller 11. When the impeller 11 moves towards the right side, the pump cover 10 is fixed, the liquid outflow is reduced along with the reduction of the gap between the balance throttling ring 8 and the wear-resisting ring 6, the pressure in the balance cavity 13 is increased, and the pressure born by the impeller balance cavity cover plate 12 is increased until the pressure sum of the pressure born by the impeller balance cavity cover plate 12 and the pressure born by the impeller rear cover plate 3 is balanced with the pressure born by the impeller front cover plate 2, so that the axial force born by the impeller 11 reaches a stable state. When the pressure of the outlet of the pump is reduced, the impeller 11 tends to move towards the left side through stress analysis, at the moment, the gap between the balance throttling ring 8 and the wear-resisting ring 6 is gradually increased, the liquid outflow is increased, the pressure in the balance cavity 13 is gradually reduced, the pressure applied to the cover plate 12 of the balance cavity of the impeller is reduced until the pressure is reduced to be balanced with the pressure of the rear cover plate 3 of the impeller and the pressure of the front cover plate 2 of the impeller, so that the axial force applied to the impeller 11 is in a stable state, and the pump shaft 19 stops moving axially.

During operation of the centrifugal pump, when the axial force is unbalanced (pressure changes occur), the axial force balancing system repeats the actions until a steady state is reached. The axial movement of the impeller 11 during balancing is less than 0.2 mm.

The above-described embodiments are merely preferred embodiments of the present invention, which is not intended to be limiting in any way, and other variations and modifications are possible without departing from the scope of the invention as set forth in the appended claims.

In the description of the present invention, it is to be understood that the terms indicating an orientation or positional relationship are based on the orientation or positional relationship shown in the drawings only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

Claims

1. The utility model provides a balanced auxiliary device of self-adaptation axial force for no leakage centrifugal pump, sets up between the impeller of no leakage centrifugal pump and pump cover, its characterized in that: including wear-resisting ring and balanced throttle ring, the centrifugal pump shaft is cup jointed at the wear-resisting ring center, wear-resisting ring is through first countersunk head bolted connection impeller, the wear-resisting ring left side is equipped with the draw-in groove, impeller bottom surface joint draw-in groove, be equipped with the water conservancy diversion hole on the wear-resisting ring, the water conservancy diversion hole link up with the balancing hole of impeller, balanced throttle ring is located the wear-resisting ring right side, centrifugal pump shaft is cup jointed at balanced throttle ring center, the pump cover is equipped with the annular groove, wear-resisting ring and balanced throttle ring all imbed in the annular groove, balanced throttle ring passes through second countersunk head bolted connection on the pump cover, the clearance between wear-resisting ring and the balanced throttle ring is less than 0.05 mm.

2. The adaptive axial force balancing aid for a centrifugal pump without leakage of claim 1, wherein: and a plurality of annular throttling grooves are formed in one side, close to the wear-resisting ring, of the balance throttling ring.

3. The adaptive axial force balancing aid for a centrifugal pump without leakage of claim 1, wherein: and a first sealing gasket is arranged between the wear-resistant ring and the bottom surface of the impeller, and a through hole communicated with the balance hole is formed in the first sealing gasket.

4. The adaptive axial force balancing aid for a centrifugal pump without leakage of claim 1, wherein: and a second sealing gasket is arranged between the balance throttling ring and the bottom of the annular groove.