Effectiveness of manual ultrasonic inspection

The results of both nozzle and dissimilar metal weld (NDW) action and austenitic steel testing (AST) action of the third phase of the Programmed for Inspection of Steel Components (PISC III) show that the manual inspection technique can be very effective in both detection and sizing of flaws. The manual technique has been successfully used in the AST-action by team DH and by team YR in the NDW-action. These are in fact one team, the team of VTT, Finland. The reasons for the excellent performance of this team in both actions are discussed in the paper. The long experience in ultrasonic testing is obviously one of the main reasons; all team members are certified inspectors that regularly carry out inspections in the field. In the AST-action a clear key-factor affecting the performance is the use of mode conversion technique and the practical training and experience inspectors had in the application of this technique