Turbomachine with a long lasting position-holding system

1. A turbomachine arranged with a rotor and a stator, the turbomachine comprising:

a fluid-flow portion enabling energy to be exchanged between a fluid passing therethrough and the rotor, including at least one bladed wheel mounted on a shaft of the rotor;

an electrical portion suitable for converting electricity into work or vice versa;

radial positioning device configured to position the rotor radially; and

a contactless axial balancing device arranged on said bladed wheel, providing axial balancing for the rotor at high speed;

wherein:

the turbomachine further comprises a thrust bearing distinct from the radial positioning device, which thrust bearing provides axial balancing of the rotor at low speed, and is contactless at high speed; and

the radial positioning device is constituted solely by hydrostatic bearings to comprise the sole radial positioning device, the turbomachine including hydrostatic bearing feed circuits suitable for connecting said bearings to a source of fluid under pressure.

2. The turbomachine of claim 1 , wherein the thrust bearing includes bearing surfaces forming an angle of more than 10° relative to the axis of the rotor.

3. The turbomachine of claim 1 , wherein the thrust bearing is a hydrostatic bearing.

4. The turbomachine of claim 1 , wherein the thrust bearing is a ball bearing.

5. The turbomachine of claim 4 , wherein the ball bearing comprises an inner ring having a radially inside surface that is substantially cylindrical, with clearance being formed between said surface and an outside surface of the rotor.

6. The turbomachine of claim 1 , further including a filter upstream in the hydrostatic bearing feed.

7. The turbomachine of claim 1 , wherein the fluid-flow portion comprises a pump, and the electrical portion is an electric motor.

8. The turbomachine of claim 1 , wherein the fluid-flow portion is a turbine, and the electrical portion is an electricity generator.

9. The turbomachine of claim 1 , wherein at high speed, the axial balancing device makes use solely of the fluid flowing through the bladed wheel(s) for the purpose of holding the rotor axially in position.

10. The turbomachine of claim 1 , wherein the fluid passing through the turbomachine comprises LNG, LPG, or a refrigerant mix fluid.

11. The turbomachine device comprising both a turbomachine according to claim 1 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

12. A turbomachine device comprising both the turbomachine of claim 2 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

13. A turbomachine device comprising both the turbomachine of claim 3 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

14. A turbomachine device comprising both the turbomachine of claim 4 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

15. A turbomachine device comprising both the turbomachine of claim 5 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

16. A turbomachine device comprising both the turbomachine of claim 6 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

17. A turbomachine device comprising both the turbomachine of claim 7 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

18. A turbomachine device comprising both the turbomachine of claim 8 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

19. A turbomachine device comprising both the turbomachine of claim 9 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.

20. A turbomachine device comprising both the turbomachine of claim 10 , suitable for being connected to a source of fluid under pressure, and a changeover device configured to select the feed to the hydrostatic bearings of the turbomachine, said feed being either said source of fluid under pressure, or a main fluid circuit of the turbomachine.