At construction time the special threaded access holes are prepared in the tube walls near the hard-to-access welds providing the possibility of entering a source inside the tube for performing the radiography. Further the access holes are sealed with the use of so called radiographic plugs, which are welded on the OD surface.
In service the ID surface of the tube around the access holes is affected by flow accelerated corrosion (FAC) aggressively. The FAC damages should be detected and evaluated on regularly.
Sonotron NDT and Israel Electric (IEC) developed the inspection solution allowing the very rapid and reliable detection and evaluation of the said damages. The solution is based on the use of Phased Array modality and the unique True-to-Geometry material coverage and imaging technology implemented by Sonotron NDTs portable PA instruments of ISONIC series (ISONIC 3510, ISONIC 2010, ISONIC 2009 UPA Scope). The standard inspection software applications ISONIC EXPERT CORNER and ISONIC EXPERT CORNER developed for the shear wave flaw detection in the corner welds and the wedged linear array probes are used. Upon the geometry of the material (wall, thickness, curvature, etc) entered the ray tracing is performed automatically allowing obtaining of the easy interpretable image in real time whilst probe is placed into the desired position. The field video of the inspection is shown below: