Reactor coolant pump internals fabricated for unit 5 of India’s Kudankulam nuclear plant


The fabrication of four guide vanes have been completed, which will be mounted in the housings of the reactor coolant pump sets to be installed in unit 5 of India’s Kudankulam Nuclear Power Plant (KNPP), according to a statement by the Russian state atomic energy corporation Rosatom.  

The KNPP, located in India’s Tamil Nadu state, is being built by the state-run Nuclear Power Corporation of India Ltd (NPCIL) with the assistance of Rosatom, who are the equipment suppliers and technical consultants for the project consisting of six reactor units. 

According to the statement released last week, each guide vane consists of upper and lower discs, between which 13 guide blades are welded. The guide vanes refer to the reactor coolant pump set (RCPS) internals, which are to be mounted in the RCPS housings and are designed to direct the coolant flow inside the pumps. 

The reactor plant equipment of one power unit includes four reactor coolant pump sets, which are being manufactured in Russia by the Rosatom machine building division Atomenergomash’s subsidiary, AEM Technologies. 

“The RCPS housing is a first safety class item. At a nuclear plant it ensures coolant circulation in the primary circuit and operates under pressure of 160 atmospheres and temperature of 300 degrees”, the statement said.  

The KNPP units 1 and 2, equipped with VVER-1000 type reactors of 1,000 MW capacity each, have been connected to the grid in 2013 and 2016, respectively. These are currently India’s largest operating nuclear power units.     

The first concrete was poured into the foundation plate of the reactor building for the fifth unit of the KNPP on June 29, 2021, which marked the official commencement of the third phase of construction involving units 5 and 6. The construction of unit 6 was launched on December 20, 2021, with the first concreting in the foundation slab of the reactor building.  

Phase 2 of the KNPP construction involving units 3 and 4, to be equipped similarly with the Russian-made VVER-1000 reactors of 1,000 MW capacity each, are currently at an advanced stage.