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Olkiluoto 3: Bottom part of containment liner installed

News brief


May 19, 2006

On May 11, the bottom part of the metallic liner for the inside of the reactor containment building has been positioned on the base slab. The 8 m high liner "cup" with a diameter of about 50 m and a weight of more than 180 t had to be moved very precisely in its specified position. The wind speed for instance had to be very low. Prior to the installation, the surface of the base slab in the relevant area was accurately straightened in order to guarantee form fit later on. The installation process with one of the world's biggest heavy load cranes took about 8 hours.

The next step in this area is the work on the Inner Foundation. This is the concrete slab inside the liner and the foundation for the reactor pit and the up going structures. This work will be done throughout the next three months.

The containment liner is made of 6 mm thick steel and will be over 60 m high when installation is completed. As part of the comprehensive protection system of the EPR, it will later be fitted on the inner pre-stressed concrete wall of the two-shell construction of the reactor building. The liner ensures the gas-tightness of the containment. It is one of the numerous built-in nuclear safety systems of the new nuclear power unit.