Centrifugal pump assembly comprising at least one impeller producing flow through and an annular space divided by at least two guide vanes into part-annular-spaces

Patent metadata

Field	Value
Publication number	US-10400792-B2
Application number	US-201615294020-A
Country	US
Kind code	B2
Filing date	Oct 14, 2016
Priority date	Oct 15, 2015
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

A water supply system ( 1 ) includes an electric motor ( 8 ) and a centrifugal pump ( 7 ) which is driven by the electric motor ( 8 ) and with at least one impeller ( 10 ) which produces a main delivery flow ( 29 ) through an annular space ( 12 ) as well as a cooling fluid delivery flow ( 30 ) through a space ( 28 ) surrounding the motor ( 8 ). The annular space ( 12 ) is divided by two guide vanes into part-annular-spaces ( 23, 24 ) which have a different pressure level on operation. Each part-annular-space ( 23, 24 ) is conductively connected to the space ( 28 ) which surrounds the motor ( 8 ) and through which the cooling fluid runs (FIG. 5 ).

First claim

What is claimed is:

1. A centrifugal pump assembly for forming a part of a water supply system, the centrifugal pump assembly comprising:
an electric motor; and
a single-stage or multi-stage centrifugal pump driven by the electric motor, said centrifugal pump comprising:
at least one impeller which produces a main delivery flow through an annular space surrounding at least one pump stage;
a space surrounding the electric motor, a cooling fluid delivery flowing through the space surrounding the electric motor; and
at least two guide vanes, wherein the annular space is divided by the at least two guide vanes into part-annular-spaces, each of the part-annular spaces having a pressure level that is different than a pressure level of another one of the part-annular spaces when the at least one impeller is operated, and each part-annular-space being fluid conductively connected to the space surrounding the motor.

2. A centrifugal pump assembly according to claim 1 , wherein the guide vanes are arranged diametrically in the annular space and form part of a last pump stage or are arranged after the last pump stage, the part-annular-spaces comprising a lower annular space and an upper annular space, wherein the at least two guide vanes deflect a portion of the main delivery flow to form a motor cooling flow of fluid, at least a portion of the motor cooling flow of fluid flowing in a direction opposite the main delivery flow, the lower annular space receiving the main delivery flow and the motor cooling flow of fluid, the motor cooling flow of fluid flowing in a first direction in the lower annular space, the upper annular space receiving the motor cooling flow of fluid, the motor cooling flow of fluid moving in a second direction in the upper annular space, the second direction being opposite the first direction.

3. A centrifugal pump assembly according to claim 1 , wherein the annular space is delimited at least partly by a pump casing.

4. A centrifugal pump assembly according to claim 3 , wherein the centrifugal pump is a multi-stage centrifugal pump with a last pump stage formed by the impeller with surrounding guide vanes in the pump casing and a first and any further pump stages are arranged within the cylinder wall which inwardly delimits the annular space of the pump and is divided in an axial direction at least in sections by the guide vanes.

5. A centrifugal pump assembly according to claim 1 , wherein the guide vanes extend in one of a direction of a rotation axis of the impeller and in a direction parallel to the rotation axis of the impeller.

6. A centrifugal pump assembly according to claim 3 , wherein the guide vanes extend into a region between the impeller and a face wall delimiting the pump casing.

7. A centrifugal pump assembly according to claim 6 , wherein the fluid conductive connection comprises one or more conduit connections to the space surrounding the motor formed by one or more recesses in a face wall of the pump casing.

8. A centrifugal pump assembly according to claim 1 , wherein the guide vanes extend radially along a face wall of a pump casing and extend axially along an outer wall of the pump casing, said outer wall outwardly delimiting the annular space.

9. A centrifugal pump assembly according to claim 1 , wherein the pump is a radial centrifugal pump or a radial-axial centrifugal pump.

10. A centrifugal pump assembly according to claim 1 , wherein the pump is configured for operation with a horizontally arranged rotation axis, and that the guide vanes subdividing the annular space of the pump extend essentially in a horizontal plane, in which the rotation axis also lies.

11. A centrifugal pump assembly according to claim 1 , wherein the electric motor and the pump comprise a common shaft and the annular space of the pump is arranged aligned to the space which surrounds the motor.

12. A water supply system comprising a centrifugal pump assembly comprising:
an electric motor; and
a single-stage or multi-stage centrifugal pump driven by the electric motor, said centrifugal pump comprising:
at least one impeller which produces a main delivery flow through an annular space surrounding at least one pump stage;
a space surrounding the electric motor, a cooling fluid delivery flowing through the space surrounding the electric motor;
at least two guide vanes, wherein the annular space is divided by the at least two guide vanes into part-annular-spaces, each of the part-annular-spaces having a pressure level that is different from a pressure level of another one of the part-annular-spaces during operation of the at least one impeller, and each part-annular-space is fluid conductively connected to the space surrounding the motor; and

a housing surrounding the centrifugal pump, wherein a suction connection and a delivery connection are provided, which are arranged on a face side of the surrounding housing.

13. A water supply system according to claim 12 , wherein the suction connection and the delivery connection are arranged above one another.

14. A water supply system according to claim 12 , wherein:
the centrifugal pump assembly further comprises a diaphragm tank and motor electronics;
the electric motor is positioned in the housing; and
the centrifugal pump and the electric motor are arranged at a bottom with the diaphragm tank and the motor electronics thereabove and at a top.

15. A water supply system according to claim 12 , wherein the centrifugal pump is a multi-stage centrifugal pump with a last pump stage formed by the impeller with surrounding guide vanes in a pump casing and a first and any further pump stages are arranged within cylinder wall which inwardly delimits the annular space of the multi-stage centrifugal pump and is divided in an axial direction at least in sections by the guide vanes.

16. A water supply system according to claim 12 , wherein the guide vanes extend into a region between the impeller and a face wall delimiting a pump casing, the part-annular-spaces comprising a lower annular space and an upper annular space, wherein the at least two guide vanes deflect a portion of the main delivery flow to form a motor cooling flow of fluid, at least a portion of the motor cooling flow of fluid flowing in a direction opposite the main delivery flow, the lower annular space receiving the main delivery flow and the motor cooling flow of fluid, the motor cooling flow of fluid flowing in a first direction in the lower annular space, the upper annular space receiving the motor cooling flow of fluid, the motor cooling flow of fluid moving in a second direction in the upper annular space, the second direction being opposite the first direction.

17. A water supply system according to claim 16 , wherein the fluid conductive connection comprises one or more conduit connections to the space surrounding the motor formed by one or more recesses in a face wall of the pump casing.

18. A water supply system according to claim 16 , wherein the guide vanes extend radially along a face wall of the pump casing and extend axially along an outer wall, of the pump casing, said outer wall outwardly delimiting the annular space.

19. A water supply system according to claim 16 , wherein the pump is configured for operation with a horizontally arranged rotation axis, and that the guide vanes subdividing the annular space of the pump extend essentially in a horizontal plane, in which the rotation axis also lies.

20. A water supply system according to claim 19 , wherein the electric motor and the pump co

Assignees

• Grundfos Holding As

Inventors

• Sierakowski-Larsen Janus Lukas

Classifications

• F04D29/445

  especially adapted for liquid pumps · CPC title

• F05D2250/52

  Outlet · CPC title

• F04D13/06 Primary

  the pump being electrically driven · CPC title

• F04D1/06

  Multi-stage pumps (F04D1/02, F04D13/10 take precedence) · CPC title

• F04D29/588

  cooling or heating the machine (F04D29/5886, F04D29/5893 take precedence) · CPC title