CN111648968A

CN111648968A - Balance disc normally-open type multistage centrifugal pump

Info

Publication number: CN111648968A
Application number: CN202010545421.8A
Authority: CN
Inventors: 彭胜前; 张幸; 罗发祥; 罗优
Original assignee: Changsha Canon General Pumps Co ltd
Current assignee: Changsha Canon General Pumps Co ltd
Priority date: 2020-06-15
Filing date: 2020-06-15
Publication date: 2020-09-11

Abstract

The invention is suitable for the technical field of multistage pumps, and provides a balance disc normally-open type multistage centrifugal pump which comprises a main shaft, a suction section, a middle section, a discharge section, a main balancing device and an auxiliary balancing device, wherein the suction section, the middle section, the discharge section, the main balancing device and the auxiliary balancing device are sequentially arranged on the main shaft from left to right, the suction section and the discharge section are symmetrically arranged at two sides of the middle section, and the main balancing device and the auxiliary balancing device are arranged on the main shaft at the right side of the discharge section, so that the balance disc normally-open type multistage centrifugal pump can be realized through the matching of the components: the invention can keep the balance disc in open state to ensure the validity of balance disc, balance axial force and make the balance disc multistage centrifugal pump adapt to some special working conditions.

Description

Balance disc normally-open type multistage centrifugal pump

Technical Field

The invention belongs to the technical field of multistage pumps, and particularly relates to a balance disc normally-open type multistage centrifugal pump.

Background

The balance disc multistage centrifugal pump in the prior art comprises a pump body, wherein a rotor component is installed in the pump body, and the pump body comprises a suction section, a middle section and a discharge section. The rotor is provided with a plurality of impellers which are arranged in the same direction, the axial force borne by each impeller faces to the same direction, and a special balance mechanism is arranged for balancing the axial force and comprises a balance disc, a balance ring and a balance pipe; during the operation of the whole balance disc pump, the rotor part always axially moves continuously, and dynamic balance is kept. The balance disc multistage centrifugal pump must be used normally with the balance disc open.

The existing balance disc multistage centrifugal pump is applied to the field, the balance disc cannot be opened under partial working conditions, severe friction between the balance disc and a balance ring can be caused when the balance disc is not effectively opened under the running state, the balance disc and the balance ring are damaged due to the severe friction within extreme time, axial force balance is invalid, the balance disc multistage centrifugal pump loses drainage working capacity, and the working condition cannot be dealt with.

Failure working conditions of the balance disc multistage centrifugal pump are as follows: 1. when the stage number is two or three, the thrust generated when the two-stage impeller and the three-stage impeller of part of models start the pump is insufficient, and the balance disc cannot be opened; 2. when the variable frequency motor is driven, the frequency of the driving motor is lower than that of a 30 Hz section, and the thrust generated when the pump is started in part of models is insufficient, so that the balance disc cannot be opened; 3. when a diesel engine and a steam turbine are driven, the rotating speed is unstable, and the thrust generated when the pump is possibly started in a low-rotating-speed running state is insufficient, so that the balance disc cannot be opened.

Disclosure of Invention

The invention aims to solve the problems in the prior art, meet the application of the balance disc multi-stage centrifugal pump in the complex working conditions and provide the balance disc normally-open type multi-stage centrifugal pump.

The invention is realized in this way, a balance disc normally open type multistage centrifugal pump, characterized by comprising a main shaft, a suction section, a middle section, a discharge section, a main balancing device and an auxiliary balancing device, wherein the suction section, the middle section, the discharge section, the main balancing device and the auxiliary balancing device are sequentially arranged on the main shaft from left to right, the suction section and the discharge section are symmetrically arranged at two sides of the middle section, and the main balancing device and the auxiliary balancing device are arranged on the main shaft at the right side of the discharge section;

supplementary balancing unit includes bearing body, positive angle contact ball bearing, bearing housing, negative angle contact ball bearing, stop pin, spacing end cover, lock nut and check screw, the main shaft passes through positive angle contact ball bearing with negative angle contact ball bearing installs the bearing is internal, the main shaft tip is provided with lock nut is used for fixing, positive angle contact ball bearing with the negative angle contact ball bearing outside is provided with the bearing housing, bearing housing upper portion is passed through the stop pin is fixed in the bearing body, the bearing housing lower part is through 2 check screw fixes in the bearing body, bearing body tip passes through spacing end cover is sealed.

Furthermore, the central axes of the suction section, the middle section and the discharge section are all perpendicular to the central axis of the main shaft.

Furthermore, the suction section, the middle section and the discharge section are hermetically connected with the main shaft through shaft seal parts.

Further, the central axis of the main balancing means and the central axis of the auxiliary balancing means are collinear with the central axis of the main shaft.

After the technical scheme is adopted, the invention has the beneficial effects that: the balance disc multi-stage centrifugal pump can ensure that the balance disc of the balance disc multi-stage centrifugal pump can work effectively at a low level, so that the balance disc multi-stage centrifugal pump can meet the application requirements of medium-low-lift occasions; the invention can ensure that the balance disc of the balance disc multistage centrifugal pump can work effectively when the variable frequency motor is driven, so that the balance disc multistage centrifugal pump can meet the requirements of constant-pressure water supply and variable-lift water delivery of a boiler system. The invention can ensure that the balance disc of the balance disc multistage centrifugal pump can work effectively when the diesel engine and the steam turbine are driven, so that the balance disc multistage centrifugal pump can be used in remote areas without power supply.

Drawings

FIG. 1 is a schematic structural view of a balance disc normally open type multistage centrifugal pump of the present invention;

FIG. 2 is a schematic view of the main balancing device of the balance disk normally open type multistage centrifugal pump of the present invention;

fig. 3 is a schematic view of the auxiliary balancing device of the balancing disk normally open type multistage centrifugal pump of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1 and 3, the present invention is a balance disc normally open type multistage centrifugal pump, which is characterized in that the centrifugal pump comprises a main shaft 1, a suction section 2, a middle section 3, a discharge section 4, a main balance device 5 and an auxiliary balance device 6, wherein the suction section 2, the middle section 3, the discharge section 4, the main balance device 5 and the auxiliary balance device 6 are sequentially arranged on the main shaft 1 from left to right, the suction section 2 and the discharge section 4 are symmetrically arranged on two sides of the middle section 3, and the main balance device 5 and the auxiliary balance device 6 are mounted on the main shaft 1 on the right side of the discharge section 4;

the auxiliary balancing device 6 comprises a bearing body 61, a positive angle contact ball bearing 62, a bearing sleeve 63, a negative angle contact ball bearing 64, an anti-rotation pin 65, a limiting end cover 66, a locking nut 67 and a locking screw 68, wherein the main shaft 1 is installed in the bearing body 61 through the positive angle contact ball bearing 62 and the negative angle contact ball bearing 64, the end part of the main shaft 1 is provided with the locking nut 67 for fixing, the bearing sleeve 63 is arranged outside the positive angle contact ball bearing 62 and the negative angle contact ball bearing 64, the upper part of the bearing sleeve 63 is fixed in the bearing body 61 through the anti-rotation pin 65, the lower part of the bearing sleeve 63 is fixed in the bearing body 61 through the 2 locking screws 68, and the end part of the bearing body 61.

The axial forces generated on the rotor components are mainly balanced by the main balancing means 5 and the auxiliary balancing means 6. The positioning of the spindle 1 with the housing is done by means of an auxiliary balancing device 6.

The central axes of the suction section 2, the middle section 3 and the discharge section 4 are all perpendicular to the central axis of the main shaft 1.

The suction section 2, the middle section 3 and the discharge section 4 are hermetically connected with the main shaft 1 through shaft seal parts.

The central axis of the main balance means 5 and the central axis of the auxiliary balance means 6 are collinear with the central axis of the main shaft 1.

As shown in fig. 2, the pressure P3 is reduced to P4 through the gap b1 and to P5 through the gap b2, and the pressure after passing through the gap of the balance disk is P6 (slightly less than P5). Because the values of P3, P4, P5 and P6 in different stages and different models are different, the numerical values of a new pump b2 in different stages are controlled during factory assembly according to the measurement data of a rotor displacement measurement system (the working principle is also described in a patent), so that the pressures of P4 and P6 are approximate, and the aim of balancing most of axial force is fulfilled.

As shown in fig. 3, the positive angle contact ball bearing 62 and the negative angle contact ball bearing 64 are arranged back to bear the action of auxiliary balance axial force; the bearing sleeve 63, the anti-rotation pin 65 and the lock nut 67 play a role in preventing the bearing outer ring from rotating; the bearing body 61, the limiting end cover 66 and the locking nut 67 play an axial limiting role, and when a new pump is delivered from a factory and assembled, the relative positions of the bearing body 61, the limiting end cover 66 and the locking nut 67 are adjusted to control the b2 gap, so that the effect of normally opening the balance disc is achieved.

The beneficial technical effects related to the implementation of the invention are as follows: the balance disc multi-stage centrifugal pump can ensure that the balance disc of the balance disc multi-stage centrifugal pump can work effectively at a low level, so that the balance disc multi-stage centrifugal pump can meet the application requirements of medium-low-lift occasions; the invention can ensure that the balance disc of the balance disc multistage centrifugal pump can work effectively when the variable frequency motor is driven, so that the balance disc multistage centrifugal pump can meet the requirements of constant-pressure water supply and variable-lift water delivery of a boiler system. The invention can ensure that the balance disc of the balance disc multistage centrifugal pump can work effectively when the diesel engine and the steam turbine are driven, so that the balance disc multistage centrifugal pump can be used in remote areas without power supply. The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The balance disc normally-open type multistage centrifugal pump is characterized by comprising a main shaft (1), a suction section (2), a middle section (3), a discharge section (4), a main balance device (5) and an auxiliary balance device (6), wherein the suction section (2), the middle section (3), the discharge section (4), the main balance device (5) and the auxiliary balance device (6) are sequentially arranged on the main shaft (1) from left to right, the suction section (2) and the discharge section (4) are symmetrically arranged on two sides of the middle section (3), and the main balance device (5) and the auxiliary balance device (6) are arranged on the main shaft (1) on the right side of the discharge section (4);

the auxiliary balancing device (6) comprises a bearing body (61), a positive angle contact ball bearing (62), a bearing sleeve (63), a negative angle contact ball bearing (64), an anti-rotation pin (65), a limiting end cover (66), a locking nut (67) and a locking screw (68), wherein the main shaft (1) is installed in the bearing body (61) through the positive angle contact ball bearing (62) and the negative angle contact ball bearing (64), the locking nut (67) is arranged at the end part of the main shaft (1) for fixing, the positive angle contact ball bearing (62) and the negative angle contact ball bearing (64) are externally provided with the bearing sleeve (63), the upper part of the bearing sleeve (63) is fixed in the bearing body (61) through the anti-rotation pin (65), the lower part of the bearing sleeve (63) is fixed in the bearing body (61) through 2 locking screws (68), the end part of the bearing body (61) is sealed by the limit end cover (66).

2. A balance disc normally open multistage centrifugal pump according to claim 1, characterized in that the central axes of the suction section (2), the intermediate section (3) and the discharge section (4) are all perpendicular to the central axis of the main shaft (1).

3. The centrifugal pump of claim 2, wherein the suction section (2), the middle section (3) and the discharge section (4) are hermetically connected with the main shaft (1) through shaft seal parts.

4. A balance disk normally open multistage centrifugal pump according to claim 1, characterized in that the central axis of the main balancing means (5) and the central axis of the auxiliary balancing means (6) are collinear with the central axis of the main shaft (1).