
Corrosion monitoring in the annular plate region of above ground storage tanks is a critical need of storage tank operators.
This region is prone to accelerated corrosion due to additional stresses caused by weight of the tank wall and the increased possibility of water entrapment under the annular plate leading to tank ruptures. Identification of this corrosion can be very difficult during internal inspection due to corrosion location (bottom side and near shell-floor joint) and floor scanners cannot inspect at the toe of shell to annular plate inner weld. Significant amount of corrosion may actually be under the inner weld toe and this may be difficult to detect. Corrosion can be very localized (< 1% ) of a tank circumference.
Traditional UT measurements have limited ability to inspect the weld toe region due to access restrictions.
Introducing TAPS (Tank Annular Plate Scanner), our robotic scanner which automates the corrosion inspection process
TAPS provides improved inspection of corrosion at the annular plate in the near shell wall region of storage tanks. TAPS uses a short-range ultrasonic guided wave technique that uses a collection of Higher Order Modes Clusters, known as HOMC.