Failure Analysis of a Jet Engine Gearbox Drive Gearshaft Ball Bearing
- 289 Downloads
The case study presented in this article details the failure investigation of an M50 alloy steel bearing used in a jet engine gearbox drive assembly. It discusses the investigative steps and analytic tools used to determine the root cause, highlighting the importance of continuous, thorough questioning by the investigating activity. The combined analyses demonstrated that the bearing failed by a single event overload as evidenced by bulk deformation and traces of foreign material on the rolling elements. The anomalous transferred metal found on the rolling elements subsequently led to the discovery of overlooked debris in an engine chip detector, and thus resulted in a review of several maintenance practices.
KeywordsM50 Bearing Overload Foreign material
- 1.ASTM E407-07 Standard Practice for Microetching Metals and Alloys, Etchant 74Google Scholar
- 2.ASTM A892-09 Standard Guide for Defining and Rating the Microstructure of High Carbon SteelsGoogle Scholar
- 3.Branlein, J., Eschmann, P., Hasbargen, L., Weigand, K.: Ball and Roller Bearings, Theory, Design and Application, 3rd edn, pp. 35–50. Wiley, Chichester (1999)Google Scholar
- 4.Böhmer H.J., Hirsch Th., Streit E.: Rolling contact fatigue behavior of heat resistant bearing steels at high operational temperatures. In: ASTM STP 1327, Hoo J.J.C., Green W.B. (eds.) Bearings Steels: Into the 21st Century. American Society for Testing and Materials, West Conshohocken (1998)Google Scholar