A giant pipeline is being installed at the construction site of Russia’s Kursk II nuclear power plant.

The circulation pipeline has diameter of 3.128m - a third larger than any other Russian NPP. The increase in the diameter is explained by the fact that the VVER-TOI reactor project provides for two circulation pumps to circulate water between the cooling tower and the turbine condenser, rather than four, as at other[ nuclear plants] with VVER reactors," said Kursk II chief engineer Aleksey Volnov. “To ensure the supply of the required volume of water by two pumps, the diameter of the pipeline was increased. This layout is explained by the optimisation of economic and technological solutions adopted in the VVER-TOI project,” Volnov explained.

Installation of the main cooling water circulation pipeline has begun at Kursk II-1. It will circulate water between the turbine condenser and the cooling tower to cool the exhaust steam from the turbine. The total length of the circulation pipeline will be about 908m.

The piping is being installed in separate blocks that are welded together. In total, 175 units will be installed, the weight of each ranging from 2 to 8 tonnes. All units are manufactured in the reinforced metal block manufacturing shop directly at the Kursk NPP-2 construction site.

This year it is planned to install about 400 tons of a circulation pipeline, which is about 40 blocks. The specialists will have to make about 120 welded joints. The builders plan to complete the work by the end of November. After completion of the installation, the circulation pipeline will be docked with pipes laid in the foundation slab of the turbine building.