SCX Special Projects Wins Dounreay Contract

03rd August 2017

A crane designed, manufactured, tested and installed by Sheffield engineering specialists SCX Special Projects is to play a key role in the decommissioning of the former Dounreay nuclear plant in northern Scotland.

The company has been awarded a contract to help ensure the safe handling of radioactive waste as part of one of the largest and most difficult nuclear commissioning challenges in Europe.

The semi-automated overhead drum crane will be used to lift 500-litre stainless steel drums into a new £22m unit at Dounreay. The drums will be encased in cement, put into long-term storage and monitored remotely over time.

SCX Special Projects – part of the SCX Group – is working with Dounreay Site Restoration Ltd (DSRL), which is managing the decommissioning on behalf of the Nuclear Decommissioning Authority.

The Sheffield firm is bringing decades of engineering design and build experience to the contract, which involves meeting stringent safety requirements.

It is manufacturing, testing and installing the crane on the site, which closed in the mid-1990s after 50 years as a world leader in experimental fast breeder testing and development.

Andy Whitworth, director of SCX Special Projects, said: “In such a safety-critical industry you need to ensure that the equipment is reliable and safe far beyond all limits of its operation.

“High-level waste demands extreme caution, requiring engineering solutions that exhibit strength, durability, safety and quality.

“At the top of our list of priorities is that people are protected and can work with confidence in the surrounding environment.”

The contract is another significant boost for SCX in the nuclear industry, adding to its reputation in other fields, notably its design, manufacture and installation of retractable roofs at Wimbledon Centre and No.1 Courts for the All England Lawn Tennis Club.

The new waste storage facility will be an extension to the existing Dounreay Cementation Plant at the site which had three reactors, chemical reprocessing plants and various waste facilities.  The latest estimated cost of the site closure plan is £2.3bn and work is scheduled to finish around 2030.

The solution, designed specifically for DSRL, comprises a modified-off-the-shelf (MOTS) crane with semi-automated controls. The primary function of the crane is to transfer the waste storage drums to a designated position within the facility’s storage vaults.

The crane also includes SCX Special Projects’ unique MotoSuiveur hoist failsafe unit, in addition to load recovery systems and extensive CCTV surveillance. The MotoSuiveur device is of particular relevance to the nuclear sector, quickly and safely halting uncontrolled loads within a few millimetres of travel.

Dan Towers, senior project manager at SCX Special Projects, said: “In a facility handling intermediate level waste, we need to be certain that the load is safe, secure and under control to ensure that both people and the environment are kept safe. To achieve this aim, our MotoSuiveur device is incorporated into the design of the drum crane.

“It was initially developed exclusively for the nuclear crane market as an emergency failsafe hoist brake and is in operation at other Nuclear Licensed Sites. It will never allow the load to freefall 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.”