At the starting power unit No 5 with VVER-1200 water-water energetic reactor of Leningrad NPP (power unit No 1 of LNPP-2) the pre-commissioning control of the base metal and weld joints of the reactor vessel was completed.

The examination carried out with the use of nondestructive control methods proved that there were no defects or damage of the reactor vessel metal and weld joints.

The pre-commissioning control of this equipment is carried out for the second time. During the acceptance control the high quality of the reactor vessel production was proved.

Today, at the inspection stage the specialists’ task is to assess the condition of the equipment of the primary circuit after the trials carried out during the recently completed hot trial, where the technological systems were tested in the conditions similar to the operation ones.

“The reactor vessel is the most important equipment of the power unit. At the stage of hot trial it was exposed to colossal loads. By carrying out the visual and metrical, capillar and supersonic diagnostics of the reactor vessel metal we proved that operational loads (the temperature of near 280ºC and the pressure of 16.2 MPa) didn’t have a negative effect at the metal condition. That is, the reliable and safe operation of the reactor vessel is guaranteed”, the Head of the Metal Defect Detection and Technical Control Department of Leningrad NPP under construction Denis Shnel told.

He also explained that not only the reactor vessel but also the metal of the in-vessel core barrel, the core baffle and the protective tube unit passed the pre-commissioning control.

It is to be recalled that the inspection stage is the part of the pre-commissioning that requires to carry out near 30 tests in 47 days and nights in order to check and assess the technical condition of the reactor unit equipment after the hot trial. The successful completion of the main equipment inspection will prove that the newest, most powerful and modern power unit of Leningrad Nuclear Power Unit is completely ready for the physical start-up when the first fuel assemblies with the fresh nuclear fuel will be loaded into the reactor core.

The power unit No 5 of Leningrad NPP is to be started up in 2017.