Maintenance and repair of LMFBR steam generators. I. National status review

This paper recalls a few factors, related to steam generators of fast breeder reactors, which led to the construction of the Phenix and Super Phenix power plants which now enable France and her European partners to consider the construction of fast power plants in the immediate future. For the steam generators the basic options as applied to Phenix resulted from a number of considerations, principally a reduction in the potential gravity of a sodium water reaction through the adoption of a steam cycle without recirculation and therefore by a reduction in water capacity; the division of the steam generators into small scale modules, enabling any sodium water reaction to be contained, a mass production, the possibility of carrying out full scale trials on a module and qualifying the endurance and, finally, an easy intervention; maximum protection against the sodium water reactions by isolating systems on the water side and the sodium side, rapid draining by rupture disks and decompression on the water steam side. Maintenance consisted of periodic inspections of the inside of the vessel containing the modules, hydrogen detection system and valves. Experience has shown that servicing and repairs are very easy