Acoustic Emission Testing (AET)
Acoustic Emission Testing (AET) is a passive NDT technique that involves detecting and analyzing acoustic waves generated by materials under stress. These emissions, too faint to be heard by the human ear, are captured by sensitive sensors placed on the material’s surface.
When a material is subjected to stress, such as pressure, tension, or impact, it releases acoustic energy in the form of sound waves. These waves propagate through the material and are picked up by strategically placed sensors. The signals are then analyzed to identify the source, nature, and severity of the defect.
Benefits:
– Real Time Monitoring: AET allows for continuous monitoring of materials, enabling the detection of defects as they occur. This proactive approach helps prevent catastrophic failures by identifying potential problems early on.
– Sensitivity to Small Defects: AET is highly sensitive to small defects, making it ideal for detecting cracks, voids, and other flaws that may be undetectable by other NDT methods.
– Wide Applicability: AET can be used on a wide range of materials, including metals, composites, concrete, and ceramics. It is also adaptable to various shapes and sizes of components.
– Minimal Preparation: Unlike some NDT methods, AET requires minimal surface preparation. This makes it a faster and more cost-effective option in many applications.
Case Study:
Use: Distribution or storage of industrial gases
Advantages in applying AET for this case:
– Avoid to empty the vessels for internal inspection and/or hydraulic pressure test
– AET is easy to apply, and fast
– Drastically reduce the duration of the maintenance, therefore increasing the productivity
– Gives an accurate diagnosis of the health state / fitness-for-service
Codes / Regulations:
– EN-ISO 16148
– ASTM E1419 (2020)
– French Application Guide – Annex 12 (in progress)