Routine inspections turned up cracks in the graphite core of a reactor at the Hunterston B nuclear power plant in Scotland.
Unit 3 is down for a planned maintenance outage when workers discovered the keyway root cracking, which was predicted to start happening at this point in the plant’s lifetime. They do not affect operations of the plant and are well within safety limits of safe operation, said plant operator EDF Energy. Inspections of the other reactor in October 2014 found similar results. EDF said it was releasing the findings as part of a commitment to transparency.
The graphite core of the reactor is made up of 6,000 graphite bricks, with half of them containing fuel channels. The structure is designed to contain many redundant bricks. As part of the ageing process, graphite slowly loses weight. It is one area used to determine the lifespan on advanced gas-cooled reactors.
The plant received a license extension to operate until 2023.
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