Acoustic emission signals associated with damaged helical gears

Knowledge of the frequency content of Acoustic Emission (AE) is essential to assessing the mechanical integrity of structures; such information is particularly useful for source location estimates once the frequency dependent wave mode has been determined. In application to rotating machinery such as gearboxes, there has been no attempt in establishing if the frequency content of AE generated from defect gears contains any unique information to aid fault diagnosis. This report presents an investigation into the frequency content of AE generated from defective helical gears, concluding that defect-free and defective gears emit acoustic emissions with similar frequency content.