At Leningrad NPP-2, the installation of a 124-ton dry reactor shield has been completed on the third power unit under construction, which features a VVER-1200 reactor plant. The structure was placed into its design position in the reactor building during a single complex technological operation performed by specialists from the engineering division of the nuclear industry, JSC "CONCERN TITAN-2".
The steel cylinder, approximately seven meters in diameter and about five meters high, was carefully placed into the reactor shaft with strict adherence to installation tolerances.
The dry shield is one of the key elements of the passive safety system of the power unit with a VVER-1200 reactor. It is designed to protect the reactor shaft structures from thermal and radiation loads, as well as to ensure the stable operation of control and management systems.
Preparation for installation took significantly longer than the installation operation itself. Individual blocks of the structure were assembled in advance, then filled with special serpentinite concrete and subjected to prolonged heat treatment. The concrete was heated to high temperatures to remove excess moisture and achieve design strength, with the preparation cycle for each block taking several weeks.
According to experts, during operation, the structure will function as part of the passive protection of the reactor plant, reducing the impact of neutron flux and elevated temperatures on the elements of the reactor shaft.