Welding of the main coolant pipeline (MCP) has been completed at unit 2 of the first nuclear power plant (NPP) in Bangladesh, being constructed at Rooppur, according to an announcement earlier this month by the Russian state atomic energy corporation Rosatom.
Rosatom is the equipment supplier and technical consultant for the project to build two VVER-1200 type units of 1,200 MW capacity each at the site located on the eastern bank of the river Padma.
Rosatom said that its engineering division ASE took 60 days to dock, weld and heat treat the perlite part of 28 welded joints, and another six days to complete the surfacing with austenitic stainless steel that will protect the pipeline from an aggressive environment.
The main coolant pipeline (MCP) is a system of pipes connecting the key equipment of the NPP’s primary circuit. It consists of four loops, each connected to the reactor and includes a main circulation pump and a steam generator. The total length of the MCP is 140 metres, its weight is 238 tonnes, and the inner diameter is 850 mm, the statement said.
“During the NPP operation, coolant with a temperature of 320 degrees will be circulating through the MCP. Therefore, the pipeline welding is a very responsible process involving only the most experienced welders. Besides, various types of welding shall be used to weld seven centimeters of joint. Each weld joint passes seven inspections at different work stages, which guarantees its reliability and quality,” ASE Vice President and Rooppur NPP Project Director, Alexey Deriy. said.
Around 100 employees of Energospetsmontazh were engaged in the work, while Rosatom subsidiary NIKIMT-Atomstroy specialists provided technical support and expert consulting for the operations, the statement added.
Both the state-of-the-art generation III+ VVER-1200 reactor units at the Rooppur NPP, located 160 km from the Bangladesh capital Dhaka, will be equipped with active as well as passive safety systems, including molten core catchers.