Flash thermography borescope

Patent metadata

Field	Value
Publication number	US-10142565-B2
Application number	US-201615354004-A
Country	US
Kind code	B2
Filing date	Nov 17, 2016
Priority date	Apr 13, 2015
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

A flash thermography device for generating an infrared image of each of a plurality of rotating turbine components located inside a turbine. The device includes an infrared sensor for detecting thermal energy radiated by each component. The device also includes a borescope having a viewing end located on a longitudinal axis of the borescope. The borescope is positioned in an inspection port to locate the viewing end inside the turbine such that at least one component is within a field of view of the viewing end. In addition, the device includes a flash source that generates a plurality of light pulses corresponding to the number of components that rotate during a single rotation of the rotor, wherein the light pulses are oriented substantially transverse to the longitudinal. Thermal energy radiated from each component is transmitted through the borescope to the infrared sensor to enable generation infrared images.

First claim

What is claimed is:

1. A flash thermography device for generating an infrared image of a turbine component located inside a turbine, wherein the turbine includes at least one inspection port, comprising:
an infrared sensor for detecting thermal energy radiated by the component;
a borescope having sensor and viewing ends located on a longitudinal axis of the borescope, wherein the sensor end is adjacent the infrared sensor and wherein the borescope is positioned in the inspection port to locate the viewing end inside the turbine such that the component is within a field of view of the viewing end; and
a flash source that generates a light pulse that heats the component, wherein the light pulse is oriented substantially transverse to the longitudinal axis and wherein thermal energy radiated from the component is transmitted through the borescope to the infrared sensor to enable generation of the infrared image.

2. The device according to claim 1 , wherein the flash source is located adjacent the viewing end.

3. The device according to claim 2 , wherein the flash source is located underneath the viewing end.

4. The device according to claim 1 , wherein the borescope includes at least one lens.

5. The device according to claim 4 , wherein the borescope includes at least one relay lens.

6. The device according to claim 1 , wherein the infrared sensor is an infrared camera.

7. The device according to claim 1 , wherein the component is a turbine blade.

8. The device according to claim 1 , wherein a duration of the light pulse is approximately 2 to 15 milliseconds.

9. A flash thermography device for generating an infrared image of each of a plurality of turbine components attached to a rotor, wherein rotation of the rotor causes rotation of the components and the turbine includes at least one inspection port, comprising:
an infrared sensor for detecting thermal energy radiated by each component;
a borescope having at least one lens positioned between sensor and viewing ends, wherein the at least one lens and the sensor and viewing ends are located on a longitudinal axis of the borescope and wherein the sensor end is adjacent the infrared sensor and the borescope is positioned in the inspection port to locate the viewing end inside the turbine such that at least one component is within a field of view of the viewing end; and
a flash source that generates a plurality of light pulses corresponding to the number of components that rotate during a single rotation of the rotor, wherein the light pulses are oriented substantially transverse to the longitudinal axis and each light pulse heats a corresponding component wherein thermal energy radiated from each component is transmitted through the borescope to the infrared sensor to enable generation of an infrared image of each component.

10. The device according to claim 9 , wherein the single rotation of the rotor is indicated by a phasor signal.

11. The device according to claim 10 further including a data acquisition system used to synchronize the phasor signal with the generation of light pulses.

12. The device according to claim 9 , wherein the components include a row of turbine blades.

13. The device according to claim 9 , wherein the flash source is located adjacent the viewing end.

14. The device according to claim 13 , wherein the flash source is located underneath the viewing end.

15. The device according to claim 9 , wherein the borescope includes at least one relay lens.

16. The device according to claim 9 , wherein a duration of the light pulse is approximately 2 to 15 milliseconds.

17. A method for generating an infrared image of each of a plurality of turbine components attached to a rotor, wherein rotation of the rotor causes rotation of the components and the turbine includes at least one inspection port, comprising:
providing an infrared sensor for detecting thermal energy radiated by each component;
providing a borescope having sensor and viewing ends located on a longitudinal axis of the borescope, wherein the sensor end is adjacent the infrared sensor;
inserting the borescope in the inspection port to locate the viewing end inside the turbine such that at least one component is within a field of view of the viewing end;
generating a phasor signal indicative of a single rotation of the rotor; and
generating a plurality of light pulses corresponding to the number of components that rotate during a single rotation of the rotor, wherein the light pulses are oriented substantially transverse to the longitudinal axis and each light pulse heats a corresponding component wherein thermal energy radiated from each component is transmitted through the borescope to the infrared sensor to enable generation of an infrared image of each component.

18. The method according to claim 17 further including delaying or advancing generation of at least one light pulse to obtain a desired blade location in the infrared image.

19. The method according to claim 17 further including synchronizing the phasor signal with the generation of light pulses.

20. The method according to claim 17 , wherein the light pulses are generated by a flash source located adjacent the viewing end.

21. A method for generating an infrared image of a turbine component located inside a turbine, wherein the turbine includes at least one inspection port, comprising:
an infrared sensor for detecting thermal energy radiated by the component;
a borescope having sensor and viewing ends located on a longitudinal axis of the borescope, wherein the sensor end is adjacent the infrared sensor and wherein the borescope is positioned in the inspection port to locate the viewing end inside the turbine such that the component is within a field of view of the viewing end; and
a flash source that generates a relatively continuous flash that heats the component, wherein the flash is oriented substantially transverse to the longitudinal axis and wherein thermal energy radiated from the component is transmitted through the borescope to the infrared sensor to enable generation of the infrared image.

22. The method according to claim 21 , wherein the component includes a thermal barrier coating.

23. The method according to claim 21 , wherein a duration of the relatively continuous flash is approximately 1-2 minutes.

24. The method according to claim 21 , wherein an increase in temperature in the component of approximately 20 degrees C generates a sufficient amount of heat suitable for obtaining an infrared image.

Assignees

• Siemens Energy Inc

Inventors

• Boudin Dustin C
• Hatcher Jr Clifford
• Kulkarni Anand A

Classifications

• G02B23/2492 Primary

  Arrangements for use in a hostile environment, e.g. a very hot, cold or radioactive environment · CPC title

• G02B23/24

  Instruments {or systems} for viewing the inside of hollow bodies, e.g. fibrescopes · CPC title

• G02B23/2453

  of the proximal end · CPC title

• H04N23/555

  for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes · CPC title

• A61B1/00064

  Constructional details of the endoscope body · CPC title