The upper part of Kudankulam 5's reactor vessel

The Volgodonsk branch of AEM Technologies has started assembling the upper part of the reactor pressure vessel (RPV) for unit 5 of the Kudankulam nuclear power plant under construction in India. Two Russian-designed AES-92 VVER-1000 pressurised water reactors are being built as the third phase of the plant in the southern state of Tamil Nadu.

AEM Technologies (part of the machine-building division of Rosatom subsidiary Atomenergomash) said specialists have connected two shells of the branch pipe zone. A flange is also to be installed. It noted, when assembling the upper part of the RPV, the gap between the parts is only 1 mm.

The weight of the upper part of the VVER-1000 RPV is 169 tonnes, the height is about 5 metres, and the diameter is 4.5 metres.

After installing all the elements, the component will be moved to the welding stand with the help of a crane, where welding of two circumferential seams will begin.

Units 1 and 2 of the Kudankulam plant began commercial operations in 2014 and 2017, respectively. Construction of units 3 and 4 began in 2017 and those units are now around 50% complete.

Construction of unit 5 of the Kudankulam plant formally began in June this year with the pouring of first concrete for the foundation plate of the reactor building. Units 5 and 6 are scheduled for completion in 66 months and 75 months, respectively. This timeline would see both units completed by 2027.

There are also plans for a fourth phase of the plant - units 7 and 8 - which will to be AES-2006 units with larger VVER-1200 reactors.