Indian contractor Larsen & Toubro (L&T India), with the technical assistance of Russian specialists, has completed the installation of the dry shielding at the reactor vessel for unit 3 of the Kudankulam NPP under construction in Tamil Nadu, Russia’s Atomstroyexport (ASE) said on 11 August. Dry shielding is a cylindrical shield with a metal lining, filled with serpentinite concrete and located around the reactor vessel. It serves to weaken the neutron flux, and also helps to prevent excessive heating of the reinforced concrete structure of the reactor shaft. The equipment was manufactured by Russia’s Tyazhmash in the city of Syzran. The weight of the cylindrical screen filled with serpentinite concrete is 140 tons.

Installation of the dry shield is an important technological operation in preparation for installation of the reactor support truss and other installation operations which take place before the reactor vessel is installed in the design position.

Meanwhile, Russia’s Atommash (part of Atomenergomash – the engineering division of Rosatom) has begun to manufacture a set of steam generators for unit 5. To date, Atommash has completed the machining of the shells and large pipes that make up the steam generator and welding work is underway. Atommash previously manufactured and shipped two sets of steam generators for Kudankulam 3&4.

The Petrozavodsk branch of AEM-Technologies (also part of Atomenergomash) earlier in August began shipping the nodes of the main circulation pipeline (MCP) for unit 4. The MCP set consists of 16 pipe assemblies. The total weight of the shipment will be more than 347 tons. During August, the entire consignment will be shipped by road from Petrozavodsk to the seaport of St Petersburg for loading onto a ship. The distance from Petrozavodsk to the construction site of the Kudankulam NPP is about 10,000 kilometres.

Kudankulam is being constructed under a 1988 Russian-Indian agreement which was amended in 1998. The general contractor (in terms of detailed design, equipment supply and technical assistance) is Atomstroyexport, the general designer is Atomenergoproekt. Atomenergomash is a supplier of key equipment. Kudankulam is one of the largest nuclear power projects in India and is scheduled to have six Russian VVER-1000 reactors. Units 1 and 2 are in operation, units 3 and 4 are under construction and units 5 and 6 planned with preparatory works in progress.

Image Source: Kudankulam