According to Atomenergomash, the operation was completed by its subsidiary Atommash in 25 days and involved continuous heating at temperatures between 150C and 300C. The 250-tonne RPV component was then placed in a special furnace for four days to finalise the welding process.
Atomenergomash is supplying all equipment for the reactor installation and most components for the machine room of the Rooppur nuclear station.
There are two Russia-supplied 1,200-MW V-392M pressurised water reactor units under construction at the Rooppur site, about 150 km from the capital Dhaka.
First concrete for Rooppur-1 was poured in November 2017 and for Rooppur-2 in July 2018. A general contract was signed between Russia and Bangladesh in 2015.
In May, Atommash completed welding of the entire RPV for Unit 1 at Rooppur.