Ultrasonic Testing (UT) is a volumetric test that uses high frequency sound energy to detect cracks and other possible welding defects in welds and materials where the internal validity is critical. This method of non destructive testing (NDT) can also be used to measure wall thickness of materials.
High frequency sound waves are passed through the testing zone using different probe angles to ensure the entire area under examination has been scanned.
Imperfections are evaluated to a particular standard.
UT is a very useful and versatile method of NDT.
There are several advantages of UT that include but are not limited to:
- High accuracy in ascertaining reflector position and thus estimating size and shape of possible defects
- Minor part preparation is needed
- The UT flaw detection unit provides instantaneous results
- UT has several uses, such as thickness measurement, in addition to flaw detection, as well as lamination detection
- It is sensitive to both surface and subsurface discontinuities
- The depth of penetration for flaw detection or measurement is superior to other NDT methods
- Only single-sided access is needed when the pulse-echo technique is used