Cutting the problem down to size – another Sellafield decommissioning milestone
As the Cumbria Nuclear Solutions Ltd (CNSL) consortium celebrates a decade of safe decommissioning, the team has added another significant milestone to go along with their impressive achievements since formation in 2006.
On September 20th a CNSL team consisting of James Fisher Nuclear (JFN) and Shepley Engineers Limited (SEL) successfully started deflector plate cutting operations on the Pile Fuel Cladding Silo (PFCS) facility at Sellafield. This is the culmination of a collaborative working approach since 2012 when CNSL was awarded the first phase of the contract which would eventually see the removal of redundant steelwork in preparation for wasteretrieval operations.
Key to the success has been a full scale mock-up of the top section of the PFCS at JFN’s Egremont facility, where CNSL and Sellafield Limited (SL) teams have been co-located and working collaboratively. This allowed the CNSL team to design and manufacture, develop and optimise the equipment and processes; the Sellafield project team were also able to validate the approach and ensure that the project fitted into the overall “Silo programme". “The first phase of the project to remove debris from on top of the plates went like clockwork because of the preparatory work in the full-scale mock-up of PFCS. Whilst the debris-removal operations were on-going, we worked on the cutting process and managed to substantially increase its speed and efficiency. Transfer to site operations has been a smooth process and we are now making excellent progress” Graham Parker, JFN Project Manager The cutting is being carried out with a water jet containing entrained abrasive.
John Reekie, the JFN senior engineer commented that
“this cutting method was selected as it is quick and efficient and does not generate excessive heat or sparks. Cutting accuracy is essential for efficient operations and vital to meet strict water usage targets. Using the Full Scale Test Rig we were able to develop techniques which could meet the challenging technical requirements and overcome replicated spatial constraints whilst proving the viability of the chosen solution and simultaneously training and up-skilling operators prior to site works."
Gary Snow, Head of the PFCS programme said:
“It’s a highly unique and complex engineering challenge, but we have the right people and the right technology to safely make this key step forward in the decommissioning journey of the building.”