The Petrozavodsk branch of Rusia’s AEM-Technologies (part of Rosatom’s mechanical engineering Atomenergomash) has started manufacturing pipes for the main circulation pipeline (MCP) for unit 5 of India’s Kudankulam NPP. An anticorrosive layer was applied to the inner surface of the pipe billets by the method of electroslag surfacing.
In total, 33 pipes and sets of rings for certification of welding technology and certification of welders at installation will be welded for Kudankulam 5. The MCP with an inner diameter of 850 mm and a total length of 146 metres connects the main equipment of the primary circuit: a reactor, steam generators and main circulation pumps.
The MCP is designed for circulation of the primary coolant at temperatures up to 330 degrees Celsius under high pressure of 160 atmospheres. To protect the pipeline from the aggressive effects of the coolant, an anti-corrosion coating is applied to the inner surface of forged blanks.
Petrozavodskmash was the first Russian enterprise to master the technology for manufacturing seamless clad pipes for nuclear power plants. It has previously manufactured and shipped similar equipment for Kudankulam 3&4 and in the future will manufacture MCPs for unit 6 of this station.
First concrete for Kudankulam 5 was poured on 29 June signalling the official start of the third stage of the plant. Kudankulam is one of the largest nuclear power projects in India and is scheduled to have six Russian VVER-1000 reactors. Kudankulam 1 and 2 (stage 1) are in operation, units 3 and 4 (stage 2) are under construction and units 5 and 6 will comprise stage 3.
Photo: Manufacturing of the main circulation pipeline for Kudankulam 5 is underway (Credit: AEM technologies)