Delivering Solutions for Sellafield

RED Engineering has recently completed their first project awarded under Sellafield’s LINC scheme, a procurement portal that ‘encourages SMEs at local and national level to collaborate and deliver innovative solutions to the mission at Sellafield.’

Liaise. Innovate. Network. Collaborate.

Sellafield’s Head of Supply Chain Development & Innovation, Emma Jayne Gooch, helped to create the LINC scheme and believes that the latest RED project demonstrates how valuable the open approach is proving to be on both sides of the portal.

“We face the challenge of cleaning up a site that’s been in operation for more than 50 years and includes some of the most hazardous nuclear facilities in Europe. We’re looking at a timescale of 100 years and we are operating to the highest standards of safety and stewardship, but we are also charged with ensuring the best return on investment for the public funding we receive.

“One new way we believe will improve value is to tap into the expertise of SMEs like RED in order to speed up the development of solutions to some of the more intractable problems we have to overcome – problems we don’t have the resources or the specialist expertise to solve inhouse.

“The LINC scheme creates an environment in which we can integrate our own internal experience, capabilities and know-how with the expertise, capacity and capability of the supply chain. It’s a platform for collaboration that enables Sellafield to build long term relationships with partners who can help us develop fit-for-purpose, innovative outcomes while demonstrating value for money to the UK taxpayer. It’s helping us meet our commitment to create resilient economies and thriving communities closest to our site, and it’s also helping our supply chain and the wider economy to prosper.”

“So our challenge was to design a process that will allow a cutting head to be deployed and then articulate vertically down into the tubes where the cutting head can make two cuts to remove a 1-metre section of the pipe.”

Green Light for RED

The emphasis on outcomes is key to the LINC approach – “offering greater freedom to our supply chain in delivering outcomes rather than outputs” ­– so the ‘LINC Work Package 5’ was offered for tender as an invitation to submit an innovative solution to a very specific challenge, at the most cost-effective price and within the tightest possible timeframe.

“This,” says RED Principal Engineer Mike Crosby, who headed the successful RED bid and the project itself, “is exactly what RED is here for.”

At first glance the challenge may have seemed simple: to design and deliver a small bore stainless steel tube internal pipe cutting process. There was, of course, far more to the project than the inherent difficulties of machining stainless steel, says Mike Crosby:

“From an engineering design perspective, the main complication was that the cutting head needs to be deployed down ‘Schedule 80’ stainless steel tubes, which have a one inch nominal bore but comparatively thick, 4mm walls. In addition the tool has to be inserted around internal structures that require at least one right angle turn in the drive train.”

For Sellafield, this is a tiny problem in the context of the overall challenge to remove highly radioactive waste from concrete silos in the most hazardous area on the site – the 50-year-old Magnox Swarf Storage Silos building. But without the removal of the tubes, the Magnox waste cannot be safely removed from the silo.

The tubes to be cut need to be removed before the 500-tonne SEPs (Silo Emptying Plants) that are being built to sit on steel rails above the one-metre-thick concrete operational floor, can be successfully deployed to empty the silos.

“So our challenge was to design a process that will allow a cutting head to be deployed and then articulate vertically down into the tubes where the cutting head can make two cuts to remove a 1-metre section of the pipe.”

Mike’s solution won the tender with a characteristic RED combination of off-the shelf pragmatism and design ingenuity.

“The outcome we proposed was based on adapting several existing technologies to create a unique system that will achieve the results Sellafield need with maximum efficiency and minimum delay. Our system is powered by an off-the-shelf drill unit, and we have developed an articulated drive shaft made up of a series of links. Each link has outer and inner shafts with universal joints, and we have designed a mechanism that allows the inner shafts to be pushed downwards by the operator to deploy the cutting blade through a slot at the cutting head.

Getting the design of the cutting tip right was a particular challenge, given we had to create a relatively small blade robust enough to cut 4mm of stainless steel. To accelerate the development process, we built a mock-up of a thermocouple pocket in RED’s Test Facility in Hexham to allow the completion of an extensive programme of cutting trials to optimize the tip design.”

Mike plays down the creativity of the solution, but he agrees that the unique parameters of the requirements made the project the engineering design equivalent to playing 3D chess.

“The technical aspects of developing an effective system were intriguing, because it had to be robust enough to cut stainless steel pipes and to be deployed many times, but the diameter of the pipes and the limited access meant it had to be relatively delicate. We also had to take into account small but significant variations in the diameter and depth of the ‘pockets’ in the concrete silo lids which give access to the tubes. And over and above the technical difficulties, it was crucial that the system would be user-friendly for the operators at Sellafield to use easily and effectively in a very hazardous environment.”

Collaboration Works for RED…

The LINC 5 challenge has allowed RED to demonstrate its capabilities as a world class problem solver, but it has also validated the benefits of the LINC scheme. They have done exactly what they said on the tin, says Mike Crosby.

“The project has been made a lot easier by Sellafield’s collaborative approach. We’ve worked very closely with key personnel to make sure we have understood exactly what is required, but the best thing about their approach is that they didn’t ask for a specific tool or solution. They gave us the challenge and we had freedom to develop the best, most practical and cost-effective solution. It was this approach that made it possible for us to do what we do best ­– draw on the best existing technology, enhance it, adapt it and create the required solution to a complicated problem as quickly as possible.”

…and Sellafield…

“We have been absolutely delighted by the innovative and collaborative approach RED has taken to this particular challenge. Becoming a new supplier to Sellafield is never easy, and there was much red tape that they had to go through in order to receive the Sellafield quality grading required. We have a delicate balancing act with LINC to ensure we have innovative new entrants to our industry, whilst appreciating that things can be slower than we would like in ensuring clearances and quality gradings. RED embraced this as an opportunity rather than an obstacle and have gone on to win further work with us. It has been an absolute joy working with the whole team at RED, who have unquavering passion, knowledge and enthusiasm for the work they do.” Emma-Jayne Gooch.