If you were probing the depths of a redundant nuclear reactor with a remotely controlled device resembling a hedgehog that toppled over when cornering, what would you do?
A Dounreay senior design engineer pondered the problem and promptly dashed home and removed the casters from his living room couch.
The low-tech solution was tested during trials in a mock-up of the pipework inside Britain’s prototype fast reactor.
Once attached the basic household furniture objects did the trick, potentially saving the project thousands in redesign and manufacturing costs.
Calder Bain, who designed the equipment and donated the casters from his family home, explained: “A considerable amount of innovation was required to build the Prototype Fast Reactor and there will be a continual requirement for pioneering methods to take a reactor of this complexity apart. This type of work gives both our young and experienced engineers the opportunity to put their innovative skills and knowledge into practice.”
The specialist heat resistant umbilical service line explored deep into the reactor core. The spiky looking attachment on wheels is clearly visible meandering its way through the now familiar route obtaining camera footage whilst measuring the radiation levels in an environment where temperatures once soared in excess of 230°C.
This final inspection confirmed that previous drilling work had been a success with the levels of sodium liquid metal vastly reduced and radiation levels lower than anticipated.
DSRL’s specialist in-house design team have created several ingenious inventions for inspecting PFR’s hazardous reactor core. This final stage of the £190k project paves the way for the next phase of reactor hazard reduction, which is the passivation work whereby the remaining sodium can be converted into a less hazardous form.
Mike Brown, reactor decommissioning unit manager said: “The reactor dismantling project is critical to the decommissioning of PFR. To safely take apart the plant we need to inspect all the hidden depths within the reactor before we can begin the final phase of work which is to remove the reactor vessel. The design of unparalleled purpose built equipment like this is a credit to all DSRL staff and its contractors involved.”