VVER-TOI reactor pressure vessel for unit 1 Russia’s Kursk-II nuclear plant (credit; Atomenergomash)Testing of the reactor pressure vessel for unit 1 of Russia's Kursk-II nuclear plant been completed. Meanwhile, construction is now underway on the cooling tower for the second reactor at the VVER-TOI nuclear power plant.

The Volgodonsk branch of AEM-Technologies (part of Rosatom’s engineering division Atomenergomash) announced it has completed hydraulic testing of the VVER-TOI reactor pressure vessel (RPV) for unit 1 Russia’s Kursk-II.

Kursk II will be the first nuclear power plant to use the VVER-TOI (typical optimised, with enhanced information) generation 3+ reactor design.

The tests were carried out in an underground caisson test bench. First, specialists installed a support ring in the stand, then, using a crane with a lifting capacity of 600 tons, they lowered the 11-metre VVER-TOI reactor vessel into the design position and closed it with a standard cover. After sealing the caisson, it was filled with distilled water, evenly heated to a temperature of 60 degrees and submitted to a pressure of 24.5MPa (250 atmospheres), which is 1.4 times higher than the operating level. The tests confirmed the strength of the base metal and welded joints of the reactor vessel and the lid.

Also on 18 December, Kursk NPP reported that work is underway on concreting the ring foundation of the cooling tower for unit 2. The cooling tower, along side the cooling tower for Kursk II-1 is the tallest structure of its kind in Russia at 179 metres in height. A total of 6000 cubic metres of concrete will be laid in the ring foundation of the evaporative cooling tower. It is planned to complete these works by the end of 2020.

The 1255MWe VVER-TOI is an evolution of Russia’s VVER-1200 project. It offers improved safety measures, including an increased margin of safety from extreme impacts and ability to withstand earthquakes, and is equipped with modern control systems and diagnostics. Construction work on the first of two units at Kursk II began in April 2018, and on the second unit in April 2019. Kursk II is a replacement station for the current Kursk nuclear plant. Commissioning of the first two units will be synchronised with the decommissioning of Kursk 1&2 of the operating plant.

Photo: VVER-TOI reactor pressure vessel for unit 1 Russia’s Kursk-II nuclear plant (Credit: Atomenergomash)