Member Article

SCX – handling Dounreay with care

It takes dedication and planning to handle some of the world’s most difficult tasks. They are not always the most spectacular or the largest, but it many cases they are deemed to be worthy of going a little more than the extra mile. Mention the words “nuclear industry” and many people are concerned. Yet the decommissioning of nuclear establishments in the UK has created a whole industry to deal with this delicate issue – and into this arena has stepped the Sheffield-based SCX Special Projects division.

In simple terms the decommissioning of old nuclear power stations requires the removal of nuclear waste. Not such as easy job when the presence of potentially lethal radioactive materials require processes to handle dangerous materials that are hazardous to the natural environment, expensive and require detailed and experienced approaches.

Dounreay Site Restoration Limited in Scotland is considered to be one of the largest and most difficult nuclear decommissioning challenges in Europe. From 1954 until 1994 it was the centre for experimental fast breeder testing and development, made up of 180 facilities including three reactors, chemical reprocessing plants and various waste facilities. At an estimated total cost of £4.5bn, the mass clean-up is scheduled to finish in 2030 but access to parts of the site will be restricted for a further 250 years. For an in-depth process of this calibre you need to be able to rely on your equipment.

The SCX Group comprises three expert engineering companies that operate as one of the UK’s leading solution providers in the fields of mechanical handling and overhead lifting equipment and controls – including their Special Projects division. The company’s custom designed high-integrity cranes and lifting solutions, coupled with their rigorous safety standards and moving expertise is proving to be an ideal fit for a number of Tier 1 projects under Government contracts at nuclear facilities across the country including Sellafield, Harwell, Hunterston, Hinkley, Trawsfynydd, Berkeley and Winfrith.

Plans for a new high-level waste (HLW) storage facility at Dounreay are well under way and SCX’s Special Projects division has recently been awarded the contract to design, manufacture and install a drum crane which will be responsible for the handling of nuclear waste at the facility. The £22 million facility will be an extension to the existing Dounreay Cementation Plant, providing more storage space for 500L stainless steel drums used to contain the encapsulated liquid waste. Here the steel drums holding liquefied radioactive waste will be encased in cement, put into long-term storage and monitored by remotely controlled operations.

Danny Pickard, Applications Engineer at SCX Special Projects, believes that in such a safety-critical industry you need to ensure that the equipment is reliable. “When dealing with high-level waste, you need to apply extreme caution and the most important thing to take into consideration is the strength and durability of your equipment. It is also crucial to keep safety and quality at the top of your list of priorities so that your staff are protected and can work with confidence in the surrounding environment. During the initial design and testing stages of the drum crane for Dounreay we will identify, analyse and resolve any potential hazards or risks in function to ensure that everything practicable is done with regards to safety.”

The 3 tonne SWL, modified-off-the-shelf (MOTS) crane designed specifically for work at Dounreay will be a semi-automatic, remote controlled crane complete with a MotoSuiveur failsafe unit, recovery systems and CCTV. The primary function of the crane will be to transfer the 500L drums containing the nuclear waste packages within the D2702 facility, from the Drum Import Enclosure to a designated position within the facility’s storage vaults. SCX Special Projects will provide a full turnkey handling solution to Dounreay. As well as designing the optimal MOTS (modified off-the-shelf) crane solution tailored to the specific safety and handling requirements of the site, SCX Special Projects will provide all the supporting documentation in accordance with stringent nuclear design codes, then undertake the manufacture, Factory Acceptance Testing (FAT), installation at Dounreay, Site Acceptance Testing (SAT) and commissioning. The entire process is scheduled for completion in time for Christmas 2016.

Danny Pickard expresses the importance of investing in a mechanically failsafe hoist device; “We understand how crucial it is to be certain that a load is safe, secure and under control in this operation. The Motosuiveur device which we have incorporated into the design of the drum crane is already in use on a number of Nuclear Licensed Sites and was initially developed exclusively for the nuclear crane market. It’s an emergency failsafe hoist brake which will never allow a free-fall condition to develop in the event of a mechanical failure or loss of control on the handled load. Instead it acts as an automatic load arrestor, bringing the load to a safe stop within 30° of angular drum rotation. In a radioactive facility this feature is fundamental to safety as nuclear waste requires the highest standards of handling to ensure people and the environment are kept safe.”

SCX Special Projects has been building its reputation in Northern Scotland with involvement in a variety of projects including work at the nearby Vulcan Naval Reactor Test Establishment (NRTE) – the Ministry of Defence’s facility for testing new designs of nuclear submarine pressurised water reactors. SCX helped to analyse different engineering solution options as well as provide design and consultancy work on their Flask Handling Facility. They are also currently revalidating a Class 1 Reactor Access Housing (RAH) crane to determine whether or not it is still safe to use.

Decades of experience in crane service, maintenance, repair and automation of overhead cranes has built a strong capability for SCX as a bespoke handling solutions provider. It is this reputation and delivery that SCX Special Projects is keen to emphasise in its work in the nuclear industry.

“We design, build and create robust and reliable lifting solutions in compliance with stringent regulations and critical requirements. Due to the safety-critical nature of the nuclear industry, each decommissioning job is entirely unique and we can finely tune solutions to fit these specific requirements. Whatever the job, we start with in-depth consultations, flexible project management and high levels of customer care.

“Our experience of working at these sites in Scotland, combined with our expert knowledge of the nuclear industry from previous projects, has enabled us to showcase our experience and technologies in the demanding industry. This will prove highly beneficial for SCX and our partners in the coming years,” said Pickard.

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