Abstract
Pulsed Eddy Current (PEC) is a proven inspection method used for the detection and assessment of Corrosion Under Insulation (CUI), Corrosion Under Fireproofing (CUF), and material loss under various types of coatings or materials that prevent direct access to the surface. In recent years, PEC inspections have become increasingly common, enabled by more sensitive sensors and innovations that increased productivity such as dynamic scanning and Pulsed Eddy Current Array (PECA) sensors. The technology remains cross sensitive to wall loss and changes in electromagnetic properties or the presence of interfering components. This limitation renders analysis difficult on more complex geometries. The objective of this paper is to introduce an innovative data analysis tool for PEC technology. The new signal representation correlates localized changes in wall thickness measurement with signal amplitude changes to discriminate real wall loss from material property changes or interfering components. The tool provides a simple and easy to interpret vector with orientations illustrating the real or false nature of an indication. The various signatures are presented and explained based on a variety of field data and manufactured samples that demonstrate the capabilities and limitations of this new graphical representation. This innovation, used alongside existing tools, contributes to increased confidence of analysts when facing challenging applications.
