Gas turbine engine and method of assembling same

• US 20060093465A1
• Filed: 10/29/2004
• Published: 05/04/2006
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Moniz, Thomas Ory, Orlando, Robert Joseph
• Granted Patent: US 7,195,447 B2
• Time in Patent Office: Days
• US Class Current: 415/68
• CPC Class Codes: F01D 25/162 Bearing supports
• CPC Class Codes: F02C 3/067 having counter-rotating rotors F02C3/073 takes precedence
• CPC Class Codes: F05D 2230/64 using positioning or alignment devices for aligning or centring, e.g. pins

Abstract

A method for assembling a gas turbine engine that includes providing a low-pressure turbine inner rotor that includes a first plurality of turbine blade rows configured to rotate in a first direction, providing a low-pressure turbine outer rotor that includes a second plurality of turbine blade rows configured to rotate in a second direction that is opposite the first direction, coupling a turbine mid-frame assembly including a plurality of spokes within the engine such that the spokes are spaced axially forward of the inner rotor, coupling a bearing between the turbine mid-frame assembly and the inner rotor such that the inner rotor is rotatably coupled to the turbine mid-frame, and adjusting the plurality of spokes to align the bearing in a radial direction.

Claims

1. A method for assembling a gas turbine engine, said method comprising:

providing a low-pressure turbine inner rotor that includes a first plurality of turbine blade rows configured to rotate in a first direction;

providing a low-pressure turbine outer rotor that includes a second plurality of turbine blade rows configured to rotate in a second direction that is opposite the first direction;

coupling a turbine mid-frame assembly including a plurality of spokes within the engine such that the spokes are spaced axially forward of the inner rotor;

coupling a bearing between the turbine mid-frame assembly and the inner rotor such that the inner rotor is rotatably coupled to the turbine mid-frame; and

adjusting the plurality of spokes to align the bearing in a radial direction.

2. A method in accordance with claim 1 further comprising:

coupling a first housing to the bearing;

coupling a second bearing to a high-pressure turbine;

coupling a second housing to the second bearing; and

coupling the first housing to the second housing to form a hub assembly.

3. A method in accordance with claim 2 further comprising coupling a plurality of yokes to the hub assembly.

4. A method in accordance with claim 3 further comprising coupling the plurality of yokes to the plurality of spokes using at least one expandable pin.

5. A method in accordance with claim 4 wherein each spoke includes a first end and a second end, said method further comprises:

coupling each spoke first end to a respective yoke; and

coupling each spoke second end to an outer casing.

6. A method in accordance with claim 5 further comprising:

coupling at least one of a belleville washer and a wave-type washer to the second end;

coupling a mechanical fastener to the second end; and

adjusting the mechanical fastener to secure the spokes in a relatively fixed position.

7. A low-pressure turbine comprising:

an inner rotor comprising a first plurality of turbine blade rows configured to rotate in a first direction;

an outer rotor comprising a second plurality of turbine blade rows configured to rotate in a second direction that is opposite said first direction;

a turbine mid-frame assembly comprising a plurality of spokes; and

a bearing coupled to said turbine mid-frame assembly and said inner rotor, said spokes are adjustable to align said bearing in a radial direction.

8. A low-pressure turbine in accordance with claim 7 wherein said turbine mid-frame further comprises:

a hub assembly; and

at least one yoke coupled to said hub assembly.

9. A low-pressure turbine in accordance with claim 8 further comprising two expandable pins configured to couple each of said plurality of spokes to a respective yoke.

10. A low-pressure turbine in accordance with claim 8 wherein said hub assembly comprises:

a first housing coupled to said bearing;

a second bearing coupled to a high-pressure turbine; and

a second housing coupled to said second bearing.

11. A low-pressure turbine in accordance with claim 8 wherein each said spoke comprises:

a spoke first end coupled to said yoke; and

a spoke second end coupled to an outer casing.

12. A low-pressure turbine in accordance with claim 11 wherein said turbine mid-frame assembly further comprises:

at least one of a belleville washer and a wave-type washer coupled to said second end; and

a mechanical fastener coupled to said second end, said mechanical fastener configured to secure said spokes in a relatively fixed position.

13. A low-pressure turbine in accordance with claim 7 wherein said turbine mid-frame assembly comprises exactly eight spokes.

14. A low-pressure turbine in accordance with claim 7 further comprising a plurality of fairings, wherein each respective fairing at least partially circumscribes each respective spoke.

15. A gas turbine engine comprising:

an inner rotor comprising a first plurality of turbine blade rows configured to rotate in a first direction;

an outer rotor comprising a second plurality of turbine blade rows configured to rotate in a second direction that is opposite said first direction;

a turbine mid-frame assembly comprising a plurality of spokes; and

a bearing coupled to said turbine mid-frame assembly and said inner rotor, said spokes are adjustable to align said bearing in a radial direction.

16. A gas turbine engine in accordance with claim 15 wherein said turbine mid-frame further comprises:

a hub assembly; and

at least one yoke coupled to said hub assembly.

17. A gas turbine engine in accordance with claim 16 further comprising two expandable pins configured to couple each of said plurality of spokes to a respective yoke.

18. A gas turbine engine in accordance with claim 16 wherein said hub assembly comprises:

a first housing coupled to said bearing;

a bearing rotatably coupled to a high-pressure turbine; and

a second housing coupled to said second bearing.

19. A gas turbine engine in accordance with claim 16 wherein each said spoke comprises:

a first end coupled to said yoke; and

a second end coupled to an outer casing;

a washer coupled to said second end;

a mechanical fastener coupled to said second end, said mechanical fastener configured to secure said spokes in a relatively fixed position; and

a plurality of fairings, wherein each respective fairing at least partially circumscribes each respective spoke.

20. A gas turbine engine in accordance with claim 15 wherein said turbine mid-frame assembly comprises exactly eight spokes.