Abstracts ASN Report 2019

NOTABLE EVENTS 2019 Implementation of the orbital TIG process (weld on the main secondary system) Áǝƺ ȒɎǝƺȸ ȅƏǣȇ ɀɎƺƏȅ Ǽǣȇƺ ɯƺǼƳɀ In 2018, EDF decided to repair the other welds on the main steam lines. More than 50 welds are to be repaired, with the high level of quality required by the break preclusion approach. Qualification of the welding processes and verification of the performance of the non-destructive testing means are in progress. The repair work is scheduled to start in 2020. ³ɎƺƏȅ ǕƺȇƺȸƏɎȒȸɀ ǔƺƺƳɯƏɎƺȸ ɀɵɀɎƺȅ ɯƺǼƳɀ In 2018, EDF began to repair the welds on the steam generators feedwater flow control system (ARE system). ³ǣɴ ژ ɯƺǼƳɀ ǝƏɮƺ ƫƺƺȇ ȸƺȵƏǣȸƺƳِ In 2018, ASN also asked EDF to review the quality of the equipment in the Flamanville EPR reactor. In so doing, EDF revealed new deviations concerning the steam generators feedwater supply system. These deviations are currently being characterised in order to define how best to handle them. The review will continue in 2020. IN BRIEF Preparation for the operations to repair the eight penetration welds requires prior qualification of the welding processes, the non-destructive tests and the tools needed, notably for the pipe cutting and clamping phases, as well as for the heat treatment of the welds. Qualification of the welding process was started in 2019 and will continue in 2020. For each weld, EDF and Framatome are thus producing a table to assess its compliance with the requirements of the technical baseline, including that associated with the break preclusion hypotheses. The organisation approved and mandated by ASN to evaluate the compliance of these welds examines their documentation and the corresponding table and evaluates whether the prerequisites for initiating their repair have been met. At the same time, ASN checks that all the actions taken by EDF, the manufacturer Framatome and the organisation result in a weld performance process that is robust. ASN Report on the state of nuclear safety and radiation protection in France in 2019 19