PSI - Issue 16

Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

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ScienceDirect

Procedia Structural Integrity 16 (2019) 184–191

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” organizers. © 2019 The Author(s). Published by Elsevier B.V. Peer- review under responsibility of the 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” organizers Keywords: transport; aviation; gear wheel; fatigue wear; technical diagnostics; frequency modulation; angular speed modulation; characteristic set; helicopter transmission. This article is devoted to observation results of gear wheel wear of two different types of helicopter transmission: reduction gear of Mi-2 helicopter engine as well as accessory gearbox (AGB) of Mi-24 helicopter using proprietary FAM-C and FDM-A ethods. The substantial sensitivity and complementarity of the observed phenomena was established – it is possible to simultaneously observe a given pair of a gear wheel and also other mecha ical points, such as, e.g. the worn out bearing of the main shaft of helicopter rotor. The authors based their deliberations on the results of laboratory tests and complex tests on elic ters during their operation. The article is addressed at subsequent destruction stages of a gear wheel in helicopter transmission. The authors paid high attention to the observed wear due to the so-called structural resonance observed in some helicopters, where the worn out bearing of helicopter rotor results in the destruction of the pair of gear wheels. The gear wheel equalizes its frequency of free vibrations with the damaged rolling bearin in the line of rotation axis. Due to this, occurs the synchronous acceleration and deceleration of rotational speed of the wheel under consideration, which leads to material fatigue wear at the root of two teeth. Such wear may contribute to gear teeth breakage and helicopter crash. © 2019 The Author(s). Published by Elsevier B.V. Peer- review under responsibility of the 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” organizers Keywords: transport; aviation; gear wheel; fatigue wear; technical diagnostics; frequency modulation; angular speed modulation; characteristic set; helicopter transmission. This article is devoted to observation results of gear wheel wear of two different types of helicopter transmission: reduction gear of Mi-2 helicopter engine as well as accessory gearbox (AGB) of Mi-24 helicopter using proprietary FAM-C and FDM-A methods. The substantial sensitivity and complementarity of the observed phenomena was established – it is possible to simultaneously observe a given pair of a gear wheel and also other mechanical points, such as, e.g. the worn out bearing of the main shaft of helicopter rotor. The authors based their deliberations on the results of laboratory tests and complex tests on helicopters during their operation. The article is addressed at subsequent destruction stages of a gear wheel in helicopter transmission. The authors paid high attention to the observed wear due to the so-called structural resonance observed in some helicopters, where the worn out bearing of helicopter rotor results in the destruction of the pair of gear wheels. The gear wheel equalizes its frequency of free vibrations with the damaged rolling bearing in the line of rotation axis. Due to this, occurs the synchronous acceleration and deceleration of rotational speed of the wheel under consideration, which leads to material fatigue wear at the root of two teeth. Such wear may contribute to gear teeth breakage and helicopter crash. 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” Monitoring wear of gear wheel of helicopter transmission using the FAM-C and FDM-A methods 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” Monitoring wear of gear wheel of helicopt r transmission using the FAM-C and FDM-A methods Andrzej Gębura a , Sylwester Kłysz a,b , Tomasz Tokarski a * a Air Force Institute of Technology, Księcia Bolesława St. 6, 01-494 Warsaw, post box. 96, Poland b University of Warmia and Mazury, Faculty of Technical Science, Oczapowskiego St. 11, 10-719 Olsztyn, Poland Andrzej Gębura a , Sylwester Kłysz a,b , Tomasz Tokarski a * a Air Force Institute of Technology, Księcia Bolesława St. 6, 01-494 Warsaw, post box. 96, Poland b University of Warmia and Mazury, Faculty of Technical Science, Oczapowskiego St. 11, 10-719 Olsztyn, Poland Abstract Abstract

* Corresponding author. Tel.: +48-22-261-851-642; fax: +48-22-261-431. E-mail address: andrzej.gebura@itwl.pl

2452-3216 © 2019 The Author(s). Published by Elsevier B.V. Peer- review under responsibility of the 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” organizers 2452-3216 © 2019 The Author(s). Published by Elsevier B.V. Peer- review under responsibility of the 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” organizers * Corresponding author. Tel.: +48-22-261-851-642; fax: +48-22-261-431. E-mail address: andrzej.gebura@itwl.pl

2452-3216  2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the 6th International Conference “Fracture Mechanics of Materials and Structural Integrity” organizers. 10.1016/j.prostr.2019.07.039