Results obtained from the inspection of test plates 1 and 2 of the defects detection trials

The first phase of the UKAEA defect detection trials (DDT) (described previously) was aimed at determining the ability of selected non-destructive testing (NDT) techniques to detect and correctly classify defects throughout the thickness of an RPV circumferential weld. The techniques were tested on two specially prepared test plates. Each was 1500 x 1500 x 250 mm and contained a central butt weld. These have been designated plates 1 and 2. On completion of the inspections the plates were sectioned at Ispra and in this report the results obtained by the various inspectors are compared with the results of the destructive examination. The plates were scanned ultrasonically from both the clad and the unclad face. The results from the clad face were analysed first. The times required for the initial search and the subsequent analyses were noted, although in this context it is accepted that compared with an RPV inspection the defect population in these test plates is unrealistically high. (author)