June 21, 2022, Buyukeceli, Mersin Province, Turkey. – Third tier of the internal containment (IC) has been installed in the reactor building of Akkuyu NPP Unit 2. IC is one of the main safety system elements of the nuclear power plant. It provides protection for the reactor compartment and is a support for the pipeline penetrations and the polar crane, which is used at the nuclear power plant in the maintenance operations during the nuclear reactor operation phase.


The IC consists of steel cladding, which ensures the reactor building tightness, and special concrete. Third IC tier is a welded metal structure consisting of 24 sections including two tiers of 12 sections each. The sections weighing from 5 to 7 tons and 6 meters high are welded together and assembled into a single cylindrical structure with the total weight of 321.9 tons, 12 meters high and 138 meters circumference.


After the third tier installation, the height of Unit 2 reactor building increased by 12 meters and reached 28.95 meters. After that, the specialists will have to join the second and third tiers, reinforce and concrete the shell. As soon as the installation of all elements is completed, the shell will be tested for tightness.


IC installation is a time consuming technological operation. It took more than 12 hours to install the third tier in the designed position using the Liebherr LR 13000 heavy crawler crane.


Sections of the internal containment were delivered by sea from St. Petersburg to Akkuyu NPP construction site and assembled into a single tier. IC sections pre-assembly into a single construct took nearly 4 months.


Sergey Butckikh, First Deputy CEO - Director of NPP under construction: “Another important key event of 2022 has been completed - the third tier of Unit 2 reactor building has been installed in the designed position. After installation of the third IC tier at Unit 2, work will be carried out to build walls inside the containment area up to 8 meters mark. In parallel with the internal containment construction, work is underway to build the boundary walls and nuclear auxiliary building walls at Unit 2 main facilities, as well as work on the reactor shaft arrangement.”

Akkuyu NPP power units reactor buildings are equipped with double containment. The outer containment shell is made with reinforced concrete and designed to withstand any extreme external impacts including magnitude 9 earthquakes, tsunamis, hurricanes and their combinations.