The Ultrasonic Testing (UT) is found on the ultrasonic wave propagation within the piece. As the light waves, even the ultrasounds may be focused and are subjected to reflection and refraction phenomena, which occur at the interface between two media of different acoustic properties. It allows to determine the features and positioning of a discontinuity, since the speed of ultrasound beam is constant in a given material and only depends on the wave type. This technique is used both for thickness measurements and defectoscopic investigations.
The conventional ultrasonic testing can be based on:
- Pulse reflection, the principle found on the total or partial reflection of the ultrasonic beam when it meets a discontinuity within the test piece;
- Transparency, which provides separately the use of a transmitter and a receiver, so that the interaction with a discontinuity causes a reduction of the signal.
- Detection of surface and volumetric defects;
- Ability to test considerable thickness;
- Ability to size and position the discontinuity;
- Ability to perform tests with the piece accessibility from one side only;
- Reduced preparation of the parts;
- Real-time results;
- Very precise two-dimensional and three-dimensional representations.
- Direct surface accessibility is required;
- Very high staff training, experience and working continuity;
- It needs the use of coupling means;
- Wrinkled, irregularly shaped, very thin or inhomogeneous materials can be difficult to be inspected;
- Coarse grained or austenitic structure materials are hardly examined;
- The sensitivity is strongly related to the defect position;
- Complexity of the preliminary calibrations.
With the considerable experience gained during the years, Metalprove S.r.l. performs ultrasonic inspections of high precision and reliability, thanks to the knowledge of the international standards (EN ISO 17640, EN ISO 11666, EN ISO 23279, EN ISO 16810, EN ISO 16826, EN ISO 16809, ASME Sec. V, ASME Sec. VIII, ASTM A388, ASTM A609, etc.) and the use of both contact and immersion examination systems.