Calculating the DGS Curve for Images Reconstructed by Digital Focusing of Aperture Method

Abstract

The widespread introduction of antenna arrays into the practice of ultrasonic testing has made it possible to obtain images of reflectors using either phased array technology or digital focusing of aperture (DFA) technology. However, many current regulatory documents governing the rules for conducting ultrasonic nondestructive testing in nuclear power engineering, petrochemistry, gas production industry, etc. require determining the equivalent dimensions of reflectors. The present article proposes a method for calculating the DAF-DGS array to determine the diameter of an equivalent flat-bottomed hole (FBH) when analyzing an image. It is shown that it is more efficient to work not with the amplitude of the image, but with the integral amplitude. Numerical experiments have shown the accuracy of the order of \( \pm 0.1\) mm in determining the FBH diameter. In model experiments, the accuracy of determining the FBH diameter was better than 0.2 mm in absolute value.