A complex high technology operation was performed at the Balakovo NPP: during the scheduled repair of power unit No. 2, specialists tested the tightness and strength of the hermetically sealed enclosure of the reactor compartment (the so-called hermetic shell). The uniqueness of the operation consists in the fact that for the first time such an inspection was carried out under pressure 4 times higher than in the course of previous similar inspections of the past years.

“The containment is a localizing safety system for the power unit. It not only provides physical protection of the power unit's equipment from external natural and man-made impact, such as tornadoes and explosions, but also the safety of residents, preventing the release of radioactive substances into the environment,” explains Vladimir Gudemenko, chief specialist of the Balakovo NPP.

At the start of the tests, the containment locks and the transport hatch were completely closed. To create a test pressure through the ventilation system, the air density was reduced - the so-called evacuation was carried out. Then, a step-by-step increase in pressure to the level of 2.957 kgf / cm2 was carried out in the containment during five days. It is excessive and exceeds the operating parameters. At each stage, time was kept to check the condition of the containment for air leaks. A modern system for controlling the integrity of the sealed enclosure was purchased for this monitoring.

The performed tests have confirmed the high reliability of the containment shell of the second power unit of the plant.

50 specialists from nine subdivisions of the Balakovo NPP participated in the technical operation. The test program was developed by employees of the Balakovo nuclear power plant, approved by representatives of Atomenergoproekt, OKB Gidropress and National Research Center Kurchatov Institute.

Similar tests will also be carried out during the scheduled repairs of power unit No. 1 and 3 of the Balakovo NPP. Their purpose is to confirm the protection of the external environment from possible radiation consequences.