There has been an emerging need for inspection of VVER-1000 RPV walls below the cold leg nozzles, an area where work is difficult due to high radiation levels. Additionally, the technical requirements of RPV work in this region (precise geometry, surface finish, etc.) necessitated development of a dedicated robotic system.
Rosenergoatom awarded Diakont the contract to develop the SUDKR system, which provide automated RPV repair, including in the zone below the cold leg nozzles. Specifications were determined through working with the chief designer of the Gidropress Reactor Design Bureau, and Izhora, the reactor manufacturer.
In the summer of 2004, during a visual examination of the reactor pressure vessel of a VVER-1000 nuclear power plant, surface corrosion was detected overlaying a grid crack area of 10mm2. The reactor operator made the decision to repair the area using Diakont’s SUDKR system. Through its automation, the repair was successfully completed within a just few hours, with minimal total dose burden on staff.
The availability of fast deployment of Diakont’s SUDKR system following discovery of a repair requirement makes completing these operations more economically feasible, ensuring a higher level of nuclear power plant safety.
For more information about RPV Repair Robotics, click here.