Installation of the dome part of the inner containment shell has begun at unit I of Russia’s Kursk-II NPP, ASE (Rosatom’s engineering division) said on 5 April. The inner containment is one of the most important elements of the safety system, preventing the release of radioactive substances into the environment. Specialists of KF LLC Trest RosSEM are constructing the inner containment dome part installing reinforced blocks on the fourth tier of the reactor building. “On the fourth tier, a narrowing of the shell is envisaged for further assembly of the dome. The special feature of the tier is that the armoured blocks have consoles on which the rail track is installed for the operation of the polar crane,” explained Aleksey Buldygin, head of the Kursk-II Capital Construction Department.

The polar crane will subsequently be used to transport and install the main technological equipment of the containment area (reactor vessel, steam generators, pressure compensator). Movement of the crane along a circular path will enable it to carry out all loading and unloading operations at any point in the reactor compartment. Some 10 reinforced blocks with a height of 6.45 metres and a mass of about 31 tons are planned to be assembled by the end of April. The erection of the tier will raise the structure of the unit to the level of 43.1 metres. The dome also includes installation of the fifth and sixth tiers. According to the schedule, work on the construction of the dome should be completed in 2022.

Kursk-II is a replacement station for the current Kursk nuclear plant. Commissioning of the first two units with the new design VVER-TOI reactors will be synchronised with the decommissioning of the RBMK reactors at Kursk 1&2 of the operating plant.