RU2742704C1 - Centrifugal pump keyless rotor - Google Patents

Abstract

FIELD: pumps.

SUBSTANCE: centrifugal pump keyless rotor includes shaft, impeller, bearings, end seals, collet clamps. Shaft has completely smooth surface except for grooves made at installation place of rotor bushings. Impeller, rotor bushings, end seals, drive and field bearings, half-couplings are installed in series on the shaft. Impeller is installed on shaft with fixation collet clamp, comprising housing, two taper bushings, bolts, providing clamping force, each rotary bushing is installed on shaft due to creation of clamping force between thrust screws and shaft, so that screws rests against made on the shaft groove, each end seal is fixed on shaft by means of collet clamp, which includes housing and conical bushing, each of bearings is installed on shaft with interference and is fixed from axial movement by spring thrust ring, each half-coupling is fixed to shaft end by means of collet clamp including housing, inner and outer conical sleeves, bolts providing clamping force.

EFFECT: device provides reduced level of noise and vibration, increased reliability and service life.

1 cl, 7 dwg

Description

The keyless rotor of a centrifugal pump belongs to the field of elements of pumps and units for pumping water, aqueous solutions, as well as liquids similar to it, through main, process and auxiliary pipelines.

Known (RU 2529979 C1, 10.10.2014) a horizontal multistage sectional centrifugal pump, which includes a drive motor, a clutch connecting the pump and motor shafts, a support frame for mounting the pump and the motor. The shaft is mounted in toroidal roller bearings fixed in cantilever bearings mounted on the outside of the end caps. The pump is equipped with a device for fixing pump sections, including tie rods installed outside the pump casing and passed through channels made in end caps, the axes of which are parallel to the shaft axis and evenly spaced around it, a device for unloading the shaft from axial force, made in the form of a hydropath containing two coaxial bushings installed with a radial clearance in the area of the shaft passage through the discharge end cover, one of which is rigidly fixed on the shaft, and the other on the discharge end cover, of the stator and rotor rings, secured with pins, respectively, on the outer surface of the discharge end cover and the rotor hydropyate mounted on the shaft by means of a double-sided collet clamping device made in the form of three coaxial bushings with contacting tapered working surfaces and clamping screws that provide the ability to retract the end bushings into the central bushing when they move along the shaft axis, while the gaps between the bushings hydraulic fins, a pressure head end cover and a hydropath rotor and between the stator and rotor rings of the hydropaths form a channel for the injected water from the last section of the pump into the unloading cavity formed by the pressure head end cover, a bracket for fastening the support bearing, stator and rotor rings, a hydropath rotor and end a seal communicating through a pipeline located on the outside of the pump casing with the first pump section and the shaft alignment device. The coupling, shaft support bearings and mechanical seals are mounted on the shaft using keyless connections. This device has a fairly high level of noise and vibration.

It is known (JP 2009057967 A, 03/19/2009) a keyless clutch assembly connecting the components of the coaxial shaft in the pump, including an annular housing, the first and second elements of the shaft system, a plurality of strips located between the outer surface of the second element of the shaft system and the surface of the inner surface of the first element of the system shaft, preventing rotation relative to each other of the first and second elements of the shaft system. In this device, the noise level is quite high, the service life is insufficient.

It is known (EA 009595 B1, 28.02.2008) a sealed centrifugal pump containing a housing with an impeller placed in it, driven in rotation by a cylindrical magnetic coupling, the leading half of which is connected to the drive shaft of the electric motor, and the driven half is connected to the impeller, and the half-couplings are multi-pole with alternating poles, installed coaxially and hermetically separated by a cylindrical non-magnetic screen fixed in the housing. The device has a relatively high noise level.

It is known (RU 2487272 C1, 10.07.2013) a rotor of a centrifugal pump, including a shaft and an impeller, the impeller is fixed to the shaft by means of a double-sided collet clamping device with tapered bushings and screws, and the mechanical seals of the rotor are mounted on the shaft using one-sided collet clamping devices with with tapered bushings and screws, the pump rotor is installed in cantilever bearings external to the pump casing, both bearings are mounted on the shaft on tapered withdrawal sleeves with an axial cut. In the patent, the technical result indicates a reduction in vibrations, but nevertheless, in this device, the reduction in noise and vibration levels still remains insufficient.

This device can be taken as the closest analogue.

The technical problem is the insufficient reliability of the fixing units, a high level of vibration, noise, insufficient service life.

A keyless rotor of a centrifugal pump is offered, including a shaft, impeller, bearings, mechanical seals, collet clamps.

The shaft has a completely smooth surface with the exception of the grooves made in the place where the rotor bushings are installed.

An impeller, rotor bushings, mechanical seals, drive and field bearings, and half couplings are installed in series on the shaft.

The impeller is mounted on a shaft with a collet clamp, which includes a housing, two tapered bushings, and bolts providing a clamping force.

Each rotor sleeve is mounted on the shaft by creating a clamping force between the thrust screws and the shaft, so that the screws abut against the groove on the shaft.

Each mechanical seal is fixed to the shaft using a collet chuck, which includes a housing and a tapered bushing.

Each of the bearings is fitted on the shaft with an interference fit and secured against axial movement by a spring thrust washer.

Each coupling half is fixed to the end of the shaft by means of a collet clamp including a housing, inner and outer tapered bushings, and bolts providing clamping force.

The technical result is improved technical and economic characteristics: reduced noise and vibration, increased reliability and resource.

The technical result is provided due to the features of sequential keyless fixation to the shaft of structural elements: impeller, rotor bushings, end seals, bearings, half couplings.

The design of the keyless rotor of a centrifugal pump is illustrated by the figures:

FIG. 1 - Centrifugal pump, front view.

FIG. 2 - Centrifugal pump, right side view.

FIG. 3 - Centrifugal pump, section along the main plane.

FIG. 4 - Keyless shaft, half-coupling design.

FIG. 5 - Keyless shaft, connection design with bearing and mechanical seal.

FIG. 6 - Keyless shaft, impeller connection design.

FIG. 7 - Keyless shaft, shaft sleeve connection design.

In the illustrations, the positions indicate:

1. Centrifugal pump;

2. Housing;

3. Cover;

4. Supply pipe;

5. Outlet branch pipe;

6. Rotor;

7. Drive bearing;

8. Field bearing;

9. End seal;

10. Shaft;

11. Impeller;

12. Half-coupling;

13. Body of the half-coupling conical clamp;

14. Left tapered bushing of the half-coupling clamp;

15. Right tapered sleeve of the half-coupling clamp;

16. Bolt;

17. Rolling bearing;

18. Spring thrust ring;

19. Clamp body of mechanical seal;

20. Tapered bushing of mechanical seal clamp;

21. Bolt;

22. Housing of the conical impeller clamp;

23. Left tapered bushing of the impeller clamp;

24. Right tapered bushing of the impeller clamp;

25. Bolt;

26. Rotor bushing;

27. Thrust screw;

28. Cylindrical groove on the shaft.

The main general objective of the present invention is to create a centrifugal pump with improved technical and economic characteristics, specifically with reduced noise and vibrations, increased reliability, service life and efficiency through a complex of design improvements united by a single inventive concept in the basic pump assemblies.

The centrifugal pump 1 consists of a housing 2, a cover 3, an inlet nozzle 4, a discharge nozzle 5, a rotor 6 with a double-sided inlet wheel 11 mounted on the shaft 10, the rotor 6 rotates in bearing supports 7 and 8, and the ends of the shaft outlet 10 to the atmosphere are sealed with end seals 9. The centrifugal pump 1 includes a smooth cylindrical shaft 10 free of keyed and threaded connections.

Figure 1-2 shows a general view of the pump 1 consisting of a housing 2, a cover 3, an inlet pipe 4, an outlet pipe 5 and a rotor 6.

FIG. 3 shows a section along the main plane A-A, which shows the main elements of the pump, such as a drive bearing 7, a field bearing 8, mechanical seals 9, a smooth cylindrical shaft 10 free of keyed and threaded connections, an impeller 11, a half-coupling 12.

FIG. 4 shows the structure of fastening the half-coupling 12 on the smooth end of the shaft 10, by installing a collet clamp, which consisted of the body of the conical clamp of the half-coupling 13, the left tapered bushing of the clamp of the half-coupling 14, the right tapered bushing of the clamp of the half-coupling 15. The clamping force between the shaft 10 and the half-coupling 12 is created for by tightening the bolts 16.

FIG. 5 shows the design of fastening bearings 17 and mechanical seal 9 on a smooth shaft 10. Bearings 17 are fastened along a cylindrical fit with an interference fit on the shaft, while additionally the bearings 17 are fixed against axial movement by a spring thrust ring 18. The mechanical seal 9 is attached to the cylindrical shaft 10 by by installing a collet clamp, which consisted of a clamp body of the mechanical seal 19, a tapered bushing of the clamp of the mechanical seal 20. The clamping force between the shaft 10 and the mechanical seal 9 is created by tightening the bolts 21.

FIG. 6 shows the design of fastening the impeller 11 on a smooth shaft 10, by installing a collet clamp, which consisted of a conical clamp housing of the impeller 22, a left tapered bushing of an impeller clamp 23, a right tapered bushing of an impeller clamp 24. Clamping force between the shaft 10 and the working wheel 11 is created by tightening the bolts 25.

FIG. 7 shows the structure of fastening the rotor sleeve 26 to a smooth shaft 10 by creating a clamping force between the shaft 10 and the stop screws 27, while additionally, to prevent axial displacement of the sleeve 26, the stop screws 27 abut against the groove 28 made on the smooth cylindrical shaft 10.

The complex of structural improvements in the basic units of the pump, united by a single inventive concept, described above, allows to obtain a keyless rotor, in which all the main components are installed without backlash with a large interference, this in turn reduces the noise and vibration of the pump, increases its reliability and efficiency.

Claims (1)

The keyless rotor of a centrifugal pump, including the shaft, impeller, bearings, mechanical seals, collet clamps, characterized in that the shaft has a completely smooth surface with the exception of the grooves made in the place of installation of the rotor bushings, the impeller, rotor bushings, end seals, drive and field bearings, half couplings, and the impeller is mounted on the shaft with fixation by a collet clamp, which includes a housing, two tapered bushings, bolts providing a clamping force, each rotor bushing is installed on the shaft by creating a clamping force between the thrust screws and the shaft. in such a way that the screws abut against the groove made on the shaft, each mechanical seal is fixed to the shaft using a collet clamp, which includes a housing and a tapered bushing, each of the bearings is fitted on the shaft with an interference fit and is secured against axial movement by a spring thrust ring, each coupling half is fixed to end of the shaft using yu collet clamp, including a body, inner and outer tapered bushings, bolts providing clamping force.

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