Petrozavodsk Branch of JSC “Mechanical Engineering Division-Technology” (a part of machine-building division of Rosatom State Corporation – Atomenergomash and Karelian Regional Wing of the Russian Engineering Union) performed assembly of a lower half body of the pressurizer for power unit No.1, Akkuyu NPP. After completion of the welding and assembly operations the item was subjected to heat treatment to remove residual stress after welding.

The pressurizer half body consisting of three shell was heated up to 650 degree Centigrade in a special heat-treatment furnace intended for large-sized items and held at the above-specified temperature during 10 hours. After shot blasting and quality inspection the half body was transferred to machining.

The pressurizer is a part of the key equipment of NPP reactor hall. It is intended for pressure development and maintenance in the reactor primary circuit. The item is a thick-walled vessel, 160 mm wall thickness, the internal volume is 79 cubic meters, the assembled weight is 178 tons.

Akkuyu NPP is the first BOO (build-own-operate) project in the world’s nuclear industry. Akkuyu NPP includes four power units with Russian GenIII+ VVER reactors with enhanced safety and improved technical and economic features. Power of each NPP unit will be 1200 MW. Main manufacturing steps are supervised by Nuclear Regulatory Authority of Turkey (NDK)