Main circulation line of Belarusian nuclear power plant’s second unit welded


The main circulation line of the second power-generating unit of the Belarusian nuclear power plant has been welded, BelTA learned from representatives of the Russian state nuclear industry corporation Rosatom.
ASE Group is Rosatom’s engineering division. It acts as the general designer and the general contractor as part of the project to build the Belarusian nuclear power plant. The welding process took 70 days and became a new reference point for fulfilling similar operations at future nuclear reactors. All the 28 joints of the main circulation line were welded in this period of time. The seams were overlaid with austenitic stainless steel to protect them against corrosion. Sergei Olontsev, ASE Group senior vice president for managing Russian projects, said that the most complicated operation had been finished in a record short period of time thanks to proper organization of the process and step-by-step audit of all the operations.
The welding of the main circulation line is important because the schedule for the hydraulic testing of the reactor unit depends on the date the welding process is finished.
The welding of the main circulation line is one of the first civil engineering projects of Rosatom’s best practices system. The system was first used to weld the main circulation line of the fourth unit of the Kalinin nuclear power plant in 2010. Over 70 proposals to improve various practices had been taken into account before the welding of the main circulation line of the second unit of the Belarusian nuclear power plant began.
The main circulation line connects the primary coolant equipment: the reactor pressure vessel, steam generators, and main circulation pumps. The main circulation line is designed to enable the flow of the heat transfer agent — water as hot as 350C under pressures as high as 17.6MPa. The Belarusian nuclear power plant is being built using the Russian standard Generation III+ design AES-2006 near Ostrovets, Grodno Oblast. The Generation III+ design is fully compliant with international safety norms and recommendations of the International Atomic Energy Agency (IAEA).