The objective of the ENIQ 2nd pilot study was to show how to fully exploit the potential of technical justifications (TJ) in the qualification of inspection procedures and thereby reduce the number of test piece trials on full-scale components. As the subject of the study a ferritic BWR-type nozzle to shell weld was selected. A TJ was produced, partly relying on modelling, to predict whether a designated ultrasonic inspection would be successful in detecting the specified defects. In parallel, a test piece with deliberately introduced defects was fabricated and inspected with the inspection system specified in the TJ. Predictions and inspection results were compared. In addition, as a separate exercise, three different mathematical models were used to predict the responses of the defects in the test piece to provide information on model applicability and accuray of prediction. The ENIQ 2nd pilot study has been largely successful in showing that TJs have the potential to predict the outcome of specific inspections and to reduce or remove the need for large scale test pieces in qualifiation. The project has shown that models are available which give largely conservative predictions of defect response when used within their regimes of validity.

SELDIS Thomas; 

2006-12-19

BRITISH INST NON-DESTRUCTIVE TESTING

JRC34516

https://publications.jrc.ec.europa.eu/repository/handle/JRC34516,