The boxes are called 3 m cubes, because they contain three cubic metres of waste, but are in fact slightly oblong, so they can be stacked and stored in a very tight manner in a special repository – like shipping containers, but with a second internal skin. Once finished, the cavity between the skins is filled with concrete. The nuclear waste, which is not the most dangerous sort but still hazardous, is mixed with concrete slurry, poured into the box and the lid closed. "What you end up with, in essence, is a concrete brick with a stainless steel shell around it," says Austen Adams.
The box outer skin is duplex stainless steel, made of sheets bent and formed, and cut and welded together like a jigsaw. The box's open side is machined, including seal and bolt hole details. The lid is manufactured and machined separately, and ultimately the two pieces fit together, with a series of bolts used to ensure an airtight seal.
A large multi-axis machining centre will be required for box machining, principally the lid sealing area in the top section, and the lids themselves. Metalcraft will also need roll-forming and bending equipment, and is planning to buy a robotic plasma welding cell to reduce labour costs and improve quality control. Because quality, not cost, are paramount, customer Sellafield, not Metalcraft, is buying the equipment.
"We haven't built one yet. There is nothing particularly challenging about making these things. What is more challenging is from the point of view of controlling the quality, the recordkeeping, the traceability of parts," Adams highlights.
"This sets apart companies that can do this kind of work. They have to demonstrate the ability to provide all the necessary integrity proofs and quality assurance to make sure that there is no question whatsoever that products that leave the factory are 100% equal to the specification. It is a different world to commercial work in that respect."
The contract is in two phases. The first establishes the capability to produce two containers a week, consistently, 100% on time. By early next year, Metalcraft will have built a prototype, and will then build, perhaps, up to four other units, refining and improving the processes as it goes. Then there will be a pre-production batch of 50. During the production of that batch, Metalcraft has to produce 20 consistently, without changing the process. "Ultimately, that is a test of process integrity," Adams states. At that point, in about two years' time, the company has a shot at winning the larger contract to make 1,050 more containers in phase 2, in a steady-state production of two a week for the whole run over 10 years.
This mixture of prototyping and serial production suits Metalcraft, offers Adams. From a base in Chatteris, Cambridgeshire, it makes not only "obscure one-offs", such as the supporting metalwork for one of the largest mirrored telescopes in the world (the ESC Paranal Observatory in Chile), but also parts in serial production, such as large structural components for MRI scanners on a 24 hour delivery horizon to Siemens.
Metalcraft will make the boxes in a separate building or part of a building in Chatteris, for two reasons. Partly nuclear components often demand their own separate space, and partly the process must protect the duplex stainless steel from contamination by other metals. Once fabricated, the pre-finished containers would be transported by 40 foot container to a new facility in Cumbria, where concrete is poured into the wall cavity before delivery to the waste site at Sellafield in Seascale, Cumbria for filling with waste and closure. The contract has concentrated on the importance of making sure that the boxes continue to arrive regularly, week in and week out, because once the Pile Fuel Cladding Silo where the waste is stored is opened, closing it up again would be extremely expensive.
The contract win has proved to be a huge coup for Metalcraft. "We spent an awful lot of money on the bid," admits Adams, (pictured above) and that reflects its strategic importance for the design and manufacturing business. He explains: "The value of the bid is predicated on the whole cost of the project, including buying the machines and producing the boxes. We are looking to put in place during phase 1 capability much greater than two units a week. The reason is that this is the first contract of several yet to come for the same type of items. There are numerous studies kicking around that estimate the number of boxes required to deal with all of the waste, and the typical view is about 40,000. That is almost an industry in its own right, with a value in excess of a billion pounds. That's why we have invested heavily in putting a bid together. We want to be the number one player in nuclear decommissioning; this contract is the first step."
Sellafield says that Metalcraft's approach to skills development helped it win the deal. An on-site training academy set up in 2010, the Fenland Engineering Skills Centre, will take on 10 apprentices this year and next on what Adams describes as a traditional four-year mechanical apprenticeship programme in Metalcraft's factory, including milling, turning, drilling, welding, bending, cutting and more. Of its 170 employees, 60% have come from its own training facilities, including most of the management team, an approach that Adams describes as "quite unique."
In a way, Metalcraft has been building up to this contract ever since Adams joined Metalcraft's parent company, Avingtrans, 18 months ago as the managing director of its energy and medical division. In his first week, he seized an opportunity to join a special corporate nuclear development programme called Civil Nuclear Sharing In Growth (with the Nuclear Advanced Manufacturing Research Centre, www.namrc.co.uk/services/sig) that has provided nuclear-specific business development advice from supply chain experts. He says he was attracted to it partly out of a mandate for modernising the 120-year-old firm. Its prior nuclear supply experience in recent times was limited to supplying high-integrity nuclear waste processing equipment.
"What I recognised in the business is that a number of aspects needed to be improved, so Civil Nuclear Sharing In Growth would be a useful investment to help me get the business to where I wanted it to be. Whether it would offer leverage in nuclear was almost irrelevant."
Now the change in company culture caused by the programme is palpable, as the managing director underlines. "People are now receptive to the benefits of change, and the need to change, and can dispense with the typical defensive attitude: 'If we do something in half the time, you'll only need half the people.' We need to counter: 'No: if we can do it in half the time, we can do twice as many, and grow the business.' If you walked around the factory and spoke to people, you would feel a sense of progression, of optimism: people are looking forward and talking in the future tense."