Abstract: A method for detecting a defect in a structure of a device includes generating, only using the device, a low-frequency signal that makes the structure vibrate, generating a high-frequency signal in the structure, and measuring a vibratory signal caused by the generated low-frequency and high-frequency signals at the same time then adaptively re-sampling these measurements to obtain a re-sampled vibratory signal the power spectrum. The resampling includes a first frequency range [uBFmin; uBFmax] of width larger than 5 Hz that contains 95% of the power of the low-frequency signal, a second frequency range [uHFmin; uHFmax] of width systematically smaller than uBFmin that contains 95% of the power of the low-frequency signal. A defect is signaled in the structure if an additional power lobe is detected outside of the ranges [uBFmin; uBFmax] and [uHFmin; uHFmax].

Abstract: A device and method for inspecting and measuring weld defects in a cylindrical wall of a cylindrical conduit. The device can include an inspection head forming a probe having a proximal end and a distal end along its longitudinal axis, and of which a first side called “inner side” is provided with at least one ultrasound wave transducer. The inspection head can include a second side, called “outer side” opposite the first side that has a curved surface in the form of a cylinder fraction, and wherein the curved surface of the second side has outward facing convexity. The wave transducer can be formed of a series of juxtaposed elements, each element being both a transmitter and receiver, wherein a surface of the series is curved and in the form of a cylinder fraction, and wherein the surface of the series has outward facing concavity.

Abstract: The invention relates particularly to a device (3) for controlling and measuring welding defects on a cylindrical wall (140) such as a “vessel bottom penetration” (14) wall) (140) of a nuclear reactor, said device comprising a control head (4) forming a probe which has a proximal end (EP) and a distal end (ED), along the longitudinal axis (X-X?) thereof, and includes a first side (42), a so-called “inner” side, provided with at least one ultrasonic wave translator, characterized in that: said control head (4) comprises a second side (43), a so-called “outer” side, opposing the first side (42), which has a curved surface in the form of a cylinder fraction, with a longitudinal axis parallel to the longitudinal axis (X-X?) of the head (4) and an outwardly facing convexity; said wave translator consists of a series (5) of adjacent elements (50), each element (50) being both an emitter and a receiver, said series (5) having a curved surface in the form of a cylinder fraction in the same direction as said longitudi