At Volgodonsk Branch of JSC “Mechanical Engineering Division-Technology” (part of engineering division of Rosatom - Atomenergomash), vessel of new type of nuclear reactor - VVER-TOI (pressurized-water reactor typical optimized informatized) for first unit of Kursk NPP-2 was officially shipped.

VVER-TOI is development by Russian designers from OKB “GIDROPRESS” based on technical decisions for VVER-1200 reactors. Nuclear reactors of new type have increased power and improved technical and economic indicators, as well as increased resistance to extreme external influences and natural disasters.

During manufacturing of VVER-TOI reactor, Atommash specialists carried out entire range of tests for item, including hydraulic tests of vessel with standard upper unit cover at pressure of 24.5 MPa (250 atmospheres), which is 1.4 times higher than operating pressure. The final stage in manufacturing of item was check assembly with internals. Core barrel, core baffle, protective tube unit were installed in reactor vessel in design position. The plant's specialists, together with the customer's representatives, performed necessary control operations. As a result, all geometric parameters, alignment of elements were checked and quality of manufactured item was confirmed.

The new reactor is made of nickel-free steel. The technology provides four weld joints, instead of six, as in the VVER-1200 reactor vessel. For automatic submerged-arc welding, welding materials were used that were not previously used at Atommash. Product weight - about 340 tons.

“Creation of any new high-tech product, especially new generation reactor, is always non-trivial task. On the one hand, in the case of VVER-TOI and equipment for it, basic design decisions are already well known and have been worked out by us in practice, in production. On the other hand, in nuclear engineering, any changes in manufacturing of new product cause whole series of decisions for adapting technological process. And these are rather lengthy and complex processes. A lot depends on effectiveness of this task. At the moment, we have moved forward quite successfully" - said Igor Kotov, General Director of JSC “Mechanical Engineering Division-Technology”.

The VVER-TOI will be transported in combined way. The product will be delivered by road to special berth of Tsimlyansk reservoir, then river route along Don and Volga to berth in Voronezh. Then the product will be reloaded onto vehicles and delivered to Kurchatov. By water, item will travel 1,500 km, when transported by road train, the road route will be 300 km, while reactor vessel will cross 9 bridges.

The reactor is product of first safety class. It is vertical cylindrical vessel with elliptical bottom. The core and internals are located inside vessel. The top of reactor is hermetically sealed with cover with drives of mechanisms and regulating units and protection of reactors installed on it and nozzles for cables outlet of in-reactor control sensors.

Power units No. 1 and No. 2 of Kursk NPP-2 of generation "3+" are being constructed according to VVER-TOI project (pressurized-water reactor typical optimized informatized), and comply with all IAEA safety requirements.