Acoustic emission inspection

Acoustic emission (AE) inspection is a passive NDT method that listens for the high-frequency stress waves a defect emits as it grows under load, rather than insonifying the part the way ultrasonic testing does. Piezoelectric sensors mounted on a pressure vessel, tank, or crane structure pick up bursts from crack propagation, plastic deformation, or leakage while the item is pressurized or proof-loaded, and source location comes from the arrival-time difference across an array. AE is global and real-time: one test campaign screens a whole vessel during a single pressurization, flagging active flaws for follow-up UT or RT. It detects growing defects, not benign static ones, so it complements volumetric methods.