Following the occurrence of PWSCC events in RPV outlet nozzles welds in V.C. Summer and Ringhals 3 and 4 NPPs in 2000, ENGIE Electrabel set up an enhanced ISI program specifically dedicated to RPV and pressurizer nozzles butt welds made of nickel-based alloy 182 in Doel 3-4 and Tihange 2-3 PWR units. Specific non-destructive examinations (NDE) carried out in this framework at an increased frequency did not reveal any PWSCC indications but some non-growing sub-surface indications have been detected. It was then decided to mitigate the risk of PWSCC in all pressurizer nozzles butt welds made of nickel-based alloy 182. The paper summarizes the strategy implemented by ENGIE Electrabel to manage the risk of PWSCC in those butt welds.
|Title of host publication||Contribution of Materials Investigations and Operating Experience to Light Water NPPs’ Safety, Performance and Reliability|
|Number of pages||9|
|State||Published - 17 Sep 2018|
|Event||2018 - FONTEVRAUD 9: Contribution of Materials Investigations and Operating Experience to Light Water NPPs’ Safety, Performance and Reliability - Palais des Papes, Avignon |
Duration: 17 Sep 2018 → 20 Sep 2018
|Conference||2018 - FONTEVRAUD 9|
|Period||2018-09-17 → 2018-09-20|