Magnetic bearing protection device

Patent metadata

Field	Value
Publication number	US-10060474-B2
Application number	US-201414786593-A
Country	US
Kind code	B2
Filing date	May 6, 2014
Priority date	May 9, 2013
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A radial magnetic bearing may include an annular housing including a radial outer wall disposed between radially outer ends of two annular axial end plates and an isolation sleeve which may include a helical arrangement of a plurality of ferromagnetic wires. The isolation sleeve may be an annular structure extending axially between the two annular axial end plates, and the isolation sleeve and the annular housing may define an isolation cavity therebetween. The radial magnetic bearing may also include an isolation sleeve retainer configured to maintain a position of the isolation sleeve between the two annular axial end plates. The radial magnetic bearing may further include a plurality of laminations disposed adjacent the isolation sleeve and about a shaft of the rotating machine. A gap may be defined between the plurality of laminations and the isolation sleeve.

First claim

We claim:

1. A radial magnetic bearing of a rotating machine, comprising:
an annular housing including a radial outer wall disposed between radially outer ends of two annular axial end plates;
an isolation sleeve including a helical arrangement of a plurality of ferromagnetic wires, the isolation sleeve being an annular structure extending axially between the two annular axial end plates, and the isolation sleeve and the annular housing defining an isolation cavity therebetween;
an isolation sleeve retainer disposed at radially inner ends of the two annular axial end plates, the isolation sleeve retainer configured to maintain a position of the isolation sleeve between the two annular axial end plates; and
a plurality of laminations disposed adjacent the isolation sleeve and about a shaft of the rotating machine, a gap being defined between the plurality of laminations and the isolation sleeve.

2. The radial magnetic bearing of claim 1 , further comprising at least two transfer tubes configured to provide fluid communication between the isolation cavity and respective interfacing flanges externally located on the rotating machine.

3. The radial magnetic bearing of claim 2 , further comprising wiring extending from the annular housing to the respective interfacing flange via one or more of the at least two transfer tubes, the wiring being immersed in a fluid.

4. The radial magnetic bearing of claim 2 , wherein the at least two transfer tubes are located at or adjacent an axial end of the annular housing.

5. The radial magnetic bearing of claim 1 , wherein at least one of the two annular axial end plates is removable.

6. The radial magnetic bearing of claim 1 , further comprising a pressure regulator configured to regulate pressure inside a cavity defined by the annular housing.

7. The radial magnetic bearing of claim 6 , wherein the pressure regulator is an equalizing bellows.

8. The radial magnetic bearing of claim 1 , wherein the isolation sleeve includes one of a thermoplastic, a thermosetting plastic, and a ceramic, and the plurality of ferromagnetic wires are embedded in the isolation sleeve.

9. The radial magnetic bearing of claim 1 , wherein the plurality of ferromagnetic wires are arranged in a plurality of radially extending layers, and each wire of the plurality of ferromagnetic wires is coated with an insulating material.

10. The radial magnetic bearing of claim 1 , wherein a thickness of the isolation sleeve is from about 0.2 mm to about 1.0 mm and each ferromagnetic wire of the plurality of ferromagnetic wires has a diameter from about 0.05 mm to about 0.09 mm.

11. The radial magnetic bearing of claim 1 , wherein the isolation sleeve further comprises a plurality of non-magnetic wires at least in a portion of the isolation sleeve adjacent at least one sensor disposed in the annular housing.

12. A radial magnetic bearing for a rotating machine, comprising:
an annular housing having a radial outer wall disposed between radially outer ends of two annular axial end plates, each of the two annular axial end plates defining a central opening for a shaft of the rotating machine to extend therethrough;
an annular isolation sleeve extending axially between the respective central openings of the two annular axial end plates, the annular isolation sleeve comprising ferromagnetic powder and a plurality of non-magnetic wires helically arranged in the annular isolation sleeve; and
at least two transfer tubes configured to provide fluid communication between the annular housing and respective flanges located on an external surface of the rotating machine.

13. The radial magnetic bearing of claim 12 , wherein the ferromagnetic powder is coated with an insulating material providing insulation between individual particles of the ferromagnetic powder.

14. The radial magnetic bearing of claim 12 , wherein at least one shaft position sensor is located in the annular housing adjacent the shaft, and at least a portion of the annular isolation sleeve adjacent the at least one shaft position sensor does not include the ferromagnetic powder.

15. The radial magnetic bearing of claim 12 , wherein the annular isolation sleeve and the radial outer wall define an isolation cavity therebetween, a stator portion of the radial magnetic bearing being disposed in the isolation cavity.

16. The radial magnetic bearing of claim 15 , further comprising at least one pressure regulator configured to maintain a difference in pressure inside the isolation cavity and pressure outside the isolation cavity, such that the annular isolation sleeve is positioned against the stator portion of the radial magnetic bearing.

17. The radial magnetic bearing of claim 12 , further comprising a plurality of laminations wound on the shaft adjacent the annular isolation sleeve, a gap being defined between the plurality of laminations and the annular isolation sleeve.

18. An isolation sleeve of a canned radial magnetic bearing, the isolation sleeve being disposed between a stator portion of the canned radial magnetic bearing and a rotor supported by the canned radial magnetic bearing, the isolation sleeve comprising:
a helical arrangement of a plurality of ferromagnetic wires and a plurality of non-magnetic wires, the plurality of ferromagnetic wires and the plurality of non-magnetic wires being embedded in one of a thermoplastic, a thermosetting plastic, and a ceramic, and the plurality of ferromagnetic wires and the plurality of non-magnetic wires being arranged in a plurality of radially extending layers.

19. The isolation sleeve of claim 18 , wherein the plurality of non-magnetic wires are disposed at least in a portion of the isolation sleeve adjacent at least one sensor of the canned radial magnetic bearing.

20. The isolation sleeve of claim 18 , wherein a thickness of the isolation sleeve is from about 0.2 mm to about 1.0 mm and each ferromagnetic wire of the plurality of ferromagnetic wires and each non-magnetic wire of the plurality of non-magnetic wires has a diameter from about 0.05 mm to about 0.09 mm.

Assignees

• Dresser Rand Co
• Maier William C
• Tecza Joseph A

Inventors

• Maier William C
• Tecza Joseph A

Classifications

• F16C32/047 Primary

  Details of housings; Mounting of active magnetic bearings · CPC title

• F16C32/048

  with active support of two degrees of freedom, e.g. radial magnetic bearings · CPC title

• F16C35/00

  Rigid support of bearing units; Housings, e.g. caps, covers (F16C23/00 takes precedence) · CPC title