Experience of the Use of Detection Systems for Loose Parts and Weakly Fixed Objects in the Coolant Circulation Circuit of Novovoronezh NPP Reactor Installations
The operating organization Concern Rosenergoatom JSC pays great attention to the development of stationary systems of technical diagnostics. Over the past 20 years, almost all Russian power units have been equipped with them. This contributed both to improving the safety of operation, and ensuring reliability, and extending the life of existing nuclear power plants. Complex, high-tech diagnostic systems are moving into operational practice with great difficulty and skepticism. The systems are slowly being filled with diagnostic knowledge, but our demanding foreign customer will undoubtedly require this diagnostic knowledge.
In reactor installations with VVER, the appearance of loose, loosely attached and foreign objects in the main circulation circuit is not completely excluded.
Operational experience shows that early detection and assessment of the parameters of such incidents allows timely adoption of a set of measures aimed at eliminating or minimizing damage to the main equipment of the reactor plant. For this reason, most modern power units with pressurized water reactors (PWR, VVER) are equipped with a system for detecting loose parts and weakly fixed objects. On the blocks under construction, these systems are laid down as standard, and power units already put into commercial operation are equipped with such systems. The requirements for the system for detecting loose and weakly fixed objects are established by international standards. The research works in this field are aimed at determining the root cause of the acoustic anomaly and localization of its epicenter. Also, no less significant are the works aimed at determining the mass of a free object (FO). The most accurate definition of this parameter will allow you to get an idea of the possible nature of the FO before it is removed from the primary circuit and make a conclusion about whether this item is accidentally hit, or it is a detached part of steam generators, main circulation pumps, internal devices or shut-off and control valves.
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Link for citing the article: Voronov A.V., Slepov M.T. Experience of the Use of Detection Systems for Loose Parts and Weakly Fixed Objects in the Coolant Circulation Circuit of Novovoronezh NPP Reactor Installations. Izvestiya vuzov. Yadernaya Energetika. 2022, no. 2, pp. 15-26; DOI: https://doi.org/10.26583/npe.2022.2.02 (in Russian).