Russia’s Atommash (the Volgodonsk branch of AEM-Technologies, part of Rosatom’s engineering division, Atomenergomash) has embarked on a key stage in the manufacture of a reactor vessel for the first power unit of Kursk II.

Atomenergomash said on 11 September that Atommash specialists assembled two halves of the new generation VVER-TOI nuclear reactor into a single whole for welding the final closing seam. The lower half-body of the reactor consists of one shell and a bottom - the total weight of the structure is about 160t. The weight of the upper half-body is 180t.

The plant specialists connected the two halves using a crane with a lifting capacity of 250t and combined the blanks with each other with a maximum clearance of 1mm. The closing seam will be welded with continuous heating of the welded seam zone - from 180 to 300 degrees.

Atommash is also manufacturing the reactor internals, the reactor cover and the upper block. The reactor comprises a vertical cylindrical body with an elliptical bottom. The core and internals are located inside the housing. The top of the reactor is hermetically sealed with a lid which is fastened to the body with studs. In the upper part of the body there are nozzles for supplying and removing the coolant, as well as nozzles for emergency supply of the coolant when the circuit is depressurised.

Kursk II is a replacement station for the current Kursk nuclear power plant. Commissioning of the first two units with the new design VVER-TOI reactors will be synchronised with the decommissioning of Kursk 1&2.