Analysis of applicability of thermography to assess health of gas turbine blades

• Autorzy: Kułaszka A. , Błachnio J.
• Języki publikacji: EN

Abstrakty

EN

A gas turbine is one of the most heavily loaded, both mechanically and thermally, structural components of an aircraft turbine engine. Hence, the most common reasons for failure are overheating and thermal fatigue of the blade material. It is of great significance for the safety of aeronautical systems that service is monitored; this is carried out to verify the health of these items using all available diagnostic methods. The primary aim is to detect and identify, as early as possible, any probable hazards to the engine. The preliminary assessment of the gas turbine blades condition is carried out via a visual inspection e.g. using a video borescope. During any repair, the preliminary assessment is conducted with a visual method, which is followed with some other non-destructive inspection techniques, e.g. flaw detection, intended to provide full colour images. The essential assessment of the blade condition consists in metallographic examination which precludes further operational use of the item. Probable errors in this assessment usually result in considerable cost of unnecessary repairs of the entire engine. Presented in the paper is the pulse thermography technique being a new NDT method, which is capable of diagnosing changes in the blade condition and to detect early stages of damages to turbine blades. Results of inspections of the blades subjected to high temperature and corresponding changes in signals of thermal response of the blade material stimulated with a heat pulse have also been given. Effects of the testing work have been used to detect changes, against temperature, in thermophysical properties of super alloy used in gas turbine blades. The results have been successfully verified using metallographic examination. To conclude: the thermographic method provides good reliability of the assessment of changes in the microstructure of the blade.

Słowa kluczowe

EN

engines; aircraft engineering; mechanical engineering

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2013
• Tom: Vol. 20, No. 2
• Strony: 237--244
• Opis fizyczny: Bibliogr. 10 poz., rys.

Twórcy

autor

Kułaszka A.

• Air Force Institute of Technology Księcia Bolesława Street 6, 01-494 Warsaw Poland tel.: [phone], fax. [phone]

autor

Błachnio J.

• Air Force Institute of Technology Księcia Bolesława Street 6, 01-494 Warsaw Poland tel.: [phone] fax. [phone]
• Białystok Technical University Wiejska Street 45C, 15-351 Białystok, Poland

Bibliografia

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