Development of evaluation criteria for improving flaw description by manual ultrasonic testing

Theoretical considerations as well as measured data of defects in welds and cast iron pieces have shown that the multifrequency ultrasonic method allows to assign natural defects to a basic reflector type. Including known data of possible manufacturing - induced defects provides information on the type of defect. This leads to a more accurate flow size determination with the help of specific DGS diagrams set up for the various basic reflector types. Application of the multifrequency method largely rules out malinterpretations that may occur with the conventional DGS method. (orig./DG)