The Leningrad NPP under construction has completed the welding of the inner containment (ICS) structures of the reactor building of the power unit No 2.

Metal large-sized structures of the ICS lower and dome parts weighing 356 and 225 tons correspondingly are connected to each other and with the previous tier of the hermetic coating. The height of the reactor building with the dome, taking into account the dome’s design, has reached more than 66 meters.

16 heat exchangers of the passive heat removal system from steam generators were mounted on the inner surface of the coating, as well as operating platforms, elements of sprinkler, ventilation and lighting systems, and parts for connecting the elements of the ICS.

After the welding is completed, the Leningrad NPP-2 Metal Defectoscopy and Technical Inspection Department specialists will conduct the welded joints quality control.

“The practice of enlarged assembly of systems and equipment has proved itself well in previous years – when similar works were performed at the first power unit. Applying this technological solution, we improve the quality and accuracy of assembly and at the same time increase labor productivity, reduce the total number of assembly operations at height, and optimize the unit’s construction time”, Pavel Ivanov, the Lead Engineer of the Leningrad NPP-2 Construction Control Department, explained.

The reactor building inner containment shell is provided for by the project for the construction of new power units at Leningrad NPP. This is the nuclear power plant localizing security system. During the unit operation, the ICS will prevent the release of radioactivity into the environment.

The completion of the above-mentioned works allows to continue the erection of the ICS structures even higher, the thickness of monolithic reinforced concrete will amount to 1200 mm.