Petrozavodsk Branch of JSC “AEM-Technology” (part of Atomenergomash, the machine-building division of the State Corporation “Rosatom,” and a member of Karelian Regional Wing of the Russian Engineering Union) has finished production of the first body parts of hydroaccumulators for passive core flooding system intended for Unit 2 of Rooppur NPP (People’s Republic of Bangladesh).
The passive core flooding system is a crucial element of the NPP's safety system devised to release decay heat in the event of a serious coolant accident in the reactor's primary circuit. The system comprises eight hydroaccumulators, thick-walled vessels, each having a capacity of 120 cubic metres. During operation the accumulators are filled with boric acid solution designated for core cooling.
At Petrozvodskmash site, the shells, cylindrical components for the passive core flooding system accumulator bodies, are now being fabricated. Sheet benders are used to shape corrosion-resistant rolled steel blanks into cylinders with an inner diameter of more than four meter, after which a longitudinal weld is produced.
The body of each hydroaccumulator is composed of three shells, each weighing 15.5 tons. Assembled with the in-vessel and bottom components, a passive core flooding system accumulator weighs about 77 tons.
JSC "Atomenergomash" is the single-source manufacturer for the Rooppur NPP reactor room and a supplier for much of the turbine island equipment. The division's branches produce reactors, steam generators, pumping and heat-exchanging equipment.