Atomstroyexport (ASE) announced today it has installed the reactor pressure vessel (RPV) of unit 1 of the nuclear power plant under construction at Ostrovets in Belarus. The RPV, which weighs more than 330 tonnes, is 11 meters long and 4.5 m in diameter, was placed in position at 8.30pm on 1 April.
|The vessel is installed at unit 1 (Image: S Sevko / Belarusian NPP)
The RPV was originally built for unit 2 - AEM-Technology, another Rosatom subsidiary, said in May last year it had completed assembly of this RPV - but has been used for unit 1 instead. The RPV built for unit 1 was shipped to the construction site in October 2015, but workers dropped it during installation work in August last year. Rosatom subsidiaries OKB Gidropress and Atomstroyexport carried out an inspection of the RPV and sent the results of that to the project's customer - the Belarusian Nuclear Power Plant Company - and to Gosatomnadzor, specifically, the Nuclear and Radiation Safety Department of the Belarusian Emergencies Ministry. Although the RPV was found to be "absolutely functional", Rosatom's then director-general Sergey Kirienko agreed to a replacement and at no additional cost to the customer, other than for its transport to the site.
Before the installation operation, the RPV of the VVER-1200 unit passed an inspection by ASE and the Belarusian Nuclear Power Plant Company that found the equipment met all regulatory requirements. The installation itself was carried out in two stages: the RPV was lifted on to a transport gantry and moved to the central chamber on rails; a polar crane then placed the vessel into a vertical position and then on to the bearing ring inside the reactor pit.
Vitaly Medyakov, vice president of the Belarusian project at AO NIAEP, part of the ASE Group, said installation of the RPV had required "pinpoint precision". He added: "Since the bearing ring carries all the weight, the axis of the reactor pressure vessel and the bearing ring cannot deviate from each other by more than one millimetre," he said.
Sergey Olontsev, senior vice president of Russian projects in the ASE Group, added that an installed RPV is the "reference point" for installing the main circulation equipment of a reactor unit.
ASE Group was formed by the merger of Russian state nuclear corporation Rosatom's engineering subsidiaries, including Atomstroyexport, Atomenergoproekt and Atomproekt.
An intergovernmental agreement between Russia and Belarus specifically on cooperation in the construction of a nuclear power plant in Belarus was signed in March 2011. Operation of the first unit of the Ostrovets plant is scheduled for November 2018 and the second unit in July 2020, to give 2340 MWe net capacity on line.
Researched and written
by World Nuclear News