Specialists of Russia’s TITAN-2 have completed installation of the first tier of the internal containment shell (VZO – Vnutrennei Zatsitnoi Obolochki) for unit 7 of the Leningrad NPP (also known as Leningrad-II unit 3). Installation of the large-sized structure, about 10 metres high and 44 metres in diameter, took eight hours, and preparation for the work took several months.
“Together with the general contractor, we carefully worked out all the stages of the operation, and also used the experience of constructing two previous units (5&6) in terms of engineering solutions,” said Evgeniy Milushkin, Deputy Director for Capital Construction and Head of the Capital Construction Department of Leningrad-II. “As a result, the complex technological lifting was carried out with high quality, and the 227-tonne lower tier of the VZO, with equipment, was installed in place safely and with pinpoint precision.”
Konstantin Khudyakov, Director of the programme for Leningrad NPP facilities at TITAN-2, noted: “We have completed installation of the 1st tier of the VZO in its regular place with high quality and in a timely manner. We plan to continue to work at the same good pace, with unconditional adherence to a high level of construction and installation. Along with the VZO, we will create the outer containment, which will protect the reactor and related equipment from external influences – natural and man-made. This work will start this year.”
In the near future, builders will begin welding the VZO tier to the horizontal cladding located below, and will carry out pressure tests for pipelines and electrical cables. After reinforcing the 1st tier from the outside, it will be concreted. The general contractor’s personnel will then manufacture and install the remaining tiers of the cylindrical and dome parts of the VZO and will also install its prestressing system.
Currently Leningrad NPP has four units in operation – units 3&4 with Soviet RBMK-1000 reactors, as well units 5&6 with new VVER-1200 units (also known as Leningrad-II 1&2). Units 5&6 replaced units 1&2 with RBMK-1000 reactors, which were decommissioned in 2018 and 2020. New VVER-1200 units (7&8), now under construction, will replace units 3&4.
