IRISNDT uses ECT (including Eddy Current Array) to detect pits, corrosion, erosion, cracking, and other imperfections, in stainless steels, brass, titanium, Inconel, copper, copper-nickel, and other non-ferrous tubes.
ADVANTAGES
This technique is fast, with up to 1.2 m/s (4 feet/s) pulling speed through tubes
A couplant is not needed
Contaminants are not introduced during the inspection
The technique identifies large and small volume pits
100% of the surface of the tubes is inspected, with 360o coverage through the length
All the data is stored for review.
LIMITATIONS
Depending upon the type of probe used, circumferential cracks can be missed due to no disturbance in the flow of eddy currents
Ferromagnetic deposits on the tubes will lead to erroneous assessments
The probe needs a minimum 80% fill factor for maximum sensitivity to defects
The technique has a ±10% variance in call accuracy assessments
The tubes must be free of obstructions, however the cleaning required is minimal
