Application of wavelet transformation in eddy current testing of steam generator tubes

Abstract

Fast localization of indications of defects and structure elements in the defectoscopy of steam generator tubes is the field where the application of the wavelet transformation has great prospects. Our primary task is to find positions of potential indications within signals and the secondary task is to calculate optimal boundaries of indications with respect to their future use in the process of classification. The contribution concentrates on the choice of suitable wavelet function and parameters of localization algorithm. The basic result of this algorithm is a vector of positions of indications within the signal. Use of multiresolution wavelet analysis implies a possibility to calculate optimal boundaries of found indications. The selected algorithm and its parameters were compared using real records of steam generator tubes and artificial defects and imitations of construction elements as well.