The Petrozavodsk branch of JSC AEM-Technologies (part of Rosatom’s mechanical engineering division, Atomenergomash) has assembled the upper and lower half-shells of the pressure compensator for unit 1 of the Kursk-II NPP. The upper semi-body of the product consists of a shell and a bottom, the lower of three shells and a bottom. An anti-corrosion cladding layer is welded onto the inner surface of each of the elements. After machining, the shells are connected with circumferential seams. The final stage of the assembly of the semi-hull is the welding of the bottom. Next, the assembled half-body is sent for heat treatment to relieve residual stresses.
The pressure compensator is the key equipment of the nuclear power plant reactor hall. It is designed to create and maintain pressure in the primary circuit of the reactor. The device is a thick-walled vessel with a wall thickness of 160 mm, the internal volume of the product is 79 cubic metres, the weight of the product in the assembly is 178 tons.
Kursk-II 1&2 are being built according to the VVER-TOI project (standard optimised informatised pressurised water power reactor), which is a development of the VVER-1200 reactor design with increased capacity and improved technical and economic indicators. Kursk II is intended as a replacement station for the currently operating Kursk NPP, which comprises four RBMK reactors. Unit 1 was closed in 2021 and unit 2 is to close in 2024. Originally the commissioning of Kursk-II units 1&2 was meant to coincide with the closure of Kursk 1&2.
Image: The shell of the pressure compensator for unit 1 of the Kursk-II nuclear power plant (courtesy of Rosatom)
