Method and apparatus for performing gas turbine engine maintenance

• US 20070084210A1
• Filed: 07/19/2005
• Published: 04/19/2007
• Est. Priority Date: 07/19/2005
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Cook, Kenneth, Pasquinelli, Ronald
• Granted Patent: US 7,726,134 B2
• Time in Patent Office: Days
• US Class Current: 60/772
• CPC Class Codes: F01D 17/105 by passing part of the fluid
• CPC Class Codes: F01D 17/162 for axial flow, i.e. the vanes turning around axes which are essentially perpendicular to the rotor centre line F01D17/167 takes precedence
• CPC Class Codes: F01D 17/26 fluid, e.g. hydraulic
• CPC Class Codes: F01D 21/003 Arrangements for testing or measuring for measuring vibrations G01H
• CPC Class Codes: F05D 2230/80 Repairing, retrofitting or upgrading methods

Abstract

A method for performing maintenance on a gas turbine engine assembly includes unplugging a first connector from a first socket, the first connector electrically coupled to the engine control unit, the first socket electrically coupled to the hydromechanical unit, plugging a second connector into the first socket, the second connector electrically coupled to a driver simulator, cranking the engine core to a low speed value, and operating the driver simulator to reposition at least one of the variable stator vane assembly and the variable bypass valve from a first operational position to a second operational position that is different than the first operational position.

Claims

1. A method for performing maintenance on a gas turbine engine assembly that includes a gas turbine engine including at least one variable stator vane assembly, at least one variable bypass valve, a hydromechanical unit that includes a first servo motor coupled to the at least one variable stator vane assembly and a second servo motor coupled to the at least one variable bypass valve, and an engine control unit configured to couple to the first and second servo motors, said method comprises:

unplugging a first connector from a first socket, the first connector electrically coupled to the engine control unit, the first socket electrically coupled to the hydromechanical unit;

plugging a second connector into the first socket, the second connector electrically coupled to a driver simulator; and

operating the driver simulator to reposition at least one of the variable stator vane assembly and the variable bypass valve from a first operational position to a second operational position that is different than the first operational position.

2. A method in accordance with claim 1 wherein the driver simulator comprises a first multi-position switch that is movable to operate the driver simulator in a plurality of operational modes, said method further comprising operating the first multi-position switch in a first mode to facilitate repositioning the variable stator vane assembly from a first operational position to a second operational position.

3. A method in accordance with claim 1 wherein the driver simulator comprises a second multi-position switch that is movable to operate the driver simulator in a plurality of operational modes, said method further comprising operating the second multi-position switch in a first mode to facilitate repositioning the variable bypass valve from a first operational position to a second operational position

4. A method in accordance with claim 2 further comprising operating the driver simulator in a second mode to facilitate testing the operability of the driver simulator.

5. A method in accordance with claim 3 further comprising operating the driver simulator in a third mode to facilitate connecting or disconnecting the driver simulator from the hydromechanical unit.

6. A driver simulator for performing maintenance on a gas turbine engine assembly that includes a gas turbine engine including at least one variable stator vane assembly, at least one variable bypass valve, a hydromechanical unit that includes a first servo motor coupled to the at least one variable stator vane assembly and a second servo motor coupled to the at least one variable bypass valve, said driver simulator comprising:

a first system coupled to the hydromechanical unit and configured to reposition the variable stator vane assembly from a first operational position to a second operational position; and

a second system coupled to the hydromechanical unit and configured to reposition the variable bypass valve from a first operational position to a second operational position.

7. A driver simulator in accordance with claim 6 wherein said first system comprises a first multi-position switch that is movable to reposition the variable stator vane assembly from a first operational position to a second operational position.

8. A driver simulator in accordance with claim 6 wherein said second system comprises a second multi-position switch that is movable to reposition the variable bypass valve from a first operational position to a second operational position.

9. A driver simulator in accordance with claim 6 further comprising a power source configured to supply power to said first and second systems.

10. A driver simulator in accordance with claim 9 wherein said power source comprises a direct current power source.

11. A driver simulator in accordance with claim 9 wherein said power source comprises a direct current battery.

12. A driver simulator in accordance with claim 11 further comprising a reverse polarity switch configured to reverse the polarity between the direct current battery and the hydromechanical unit.

13. A driver simulator in accordance with claim 8 wherein said first system comprises a power source and a first meter, said first multi-position switch movable to electrically couple said power source to said first meter to facilitate determining an electrical output of said power source.

14. A driver simulator in accordance with claim 8 wherein said second system comprises a power source and a second meter, said second multi-position switch movable to electrically couple said power source to said second meter to facilitate determining an electrical output of said power source.

15. A driver simulator in accordance with claim 7 wherein said first system further comprises a first current interrupting device that is configured to interrupt the flow of electrical current from said power source to the hydromechanical unit.

16. A driver simulator in accordance with claim 8 wherein said second system further comprises a second current interrupting device that is configured to interrupt the flow of electrical current from said power source to the hydromechanical unit.

17. A driver simulator in accordance with claim 7 wherein said first system further comprises a first resistive element to regulate the flow of electrical current from a power source to the hydromechanical unit.

18. A driver simulator in accordance with claim 8 wherein said second system further comprises a second resistive element to regulate the flow of electrical current from a power source to the hydromechanical unit.

19. A driver simulator in accordance with claim 7 wherein said first multi-position switch is a three-position switch.

20. A driver simulator in accordance with claim 8 wherein said second multi-position switch is a three-position switch.