Engineering and protection that’s on point
KAEFER in UK & Ireland
From radiation-proof, perfectly painted concrete rooms to self-supporting scaffolding and steel liners that weigh more than a jumbo jet, KAEFER rises to the challenges at Hinkley Point C.
There are more than 10,000 rooms that need to be painted at the largest construction project in Europe, the Hinkley Point C nuclear power plant in Somerset, England. That’s just one challenge for KAEFER in the UK & Ireland, who were contracted to provide surface protection, specialist access and temperature-controlled environmental encapsulation within the scope of works on site.
There are also the enormous containment liners that are 57 metres tall and 47 metres in diameter. There is in excess of 20,000 m2 of steel that require abrasive blast cleaning and protective coating application with little margin for error, as these liners will surround and protect the nuclear reactors.
rooms to be painted
square metres of steel to be blasted
tonnes of scaffold materials to provide access
Where performance meets aesthetics
Whilst one could say that this is basically a high-quality paint job, the level of skill and the perfection required is on a completely different level. The concrete rooms need to be prepared in accordance with an international standard for surface profile and then protected with up to seven layers of specialist coatings (self-levelling, decontaminating, dust sealing, stratification, linings, etc.). The application process can take between four to six weeks to complete, with the result of a mirror-like finish, rather than the wall or floor of an industrial facility. “The finishing is like glass, that’s the quality that we produce,” explains Paul Ferrand, Operational Delivery Lead – HPC. “We don’t often have time to step back and take pride in our work as we’re so busy and it’s so intense. But when people finally do walk into one of these rooms and see how things are done, they are astounded.”
To achieve this standard, KAEFER operatives have to be trained and have the correct qualifications before they are allowed to apply the products to the surface on site. There are also two areas with concrete blocks that can be practised on and KAEFER also ensures that applicators in the team achieve the required specialist nuclear coatings qualifications.
“Hands-on experience is vital,” explains Ferrand. “The theory provides a good foundation, but as the saying goes, practice makes perfect.”
To share knowledge and best practise in application techniques, the teams also visited KAEFER WANNER in France, who have a great deal of experience working on nuclear power plants and applying the same products. The team has made very good progress so far, having finished 86 rooms with many more still to come.
Status of floor when handed to KAEFER
Prepared floor
Finished floor
Finished floor
Doing what some say can’t be done
If painting subterranean concrete rooms to a mirror finish doesn’t sound tough enough, working with the liners presented its own, unique challenges. The round, tall structures aren’t able to support scaffolding in the traditional way with bracing or tying, as the steel needs to be free from defects at the end of the coating process. So, KAEFER had to develop a self-supporting, curved scaffolding system to provide access. The design process involved creating digital animations and models to test whether the structure would fit and cope with the stresses it would be subjected to.
“We were able to develop the design to millimetre accuracy and instantly share the 3D models with the client to ensure that the solution satisfied both KAEFER and Bylor's operational requirements,” outlines Thomas Hurst, KAEFER's Temporary Works Coordinator and Designer for the Hinkley Point C site.
In addition to 3D modelling, KAEFER brought another significant innovation to the project: movable suspended scaffolding. Using a bespoke design focusing on buildability and minimising the need to work at height, the scaffolding was erected at ground level and then lifted into position, 35 metres high by ‘Big Carl’, the world's largest construction crane.
“We proposed a suspended scaffold design to allow the project to continue on schedule,” Hurst explains. “Other contractors had said it couldn’t be done but we were confident we could design and build a safe access system to meet the clients’ requirements.” Making the impossible possible is all in a day’s work for KAEFER at Hinkley Point C.
Atomic opportunities
In addition to the massive liners and other superlative feats of engineering at Hinkley Point C, there are also much smaller elements, such as steel ductwork. Yet when you consider that there are tens of thousands of pieces needed at the nuclear island, the job is similar in scope to the other, large-scale projects on site.
KAEFER produces high grade, precision manufactured steel ductwork at its specialist facility in Jarrow, with the first delivery arriving at Hinkley Point C in October. The contract led to the expansion of the team and has secured the future of the fabrication facility.
At any given point, there are in excess of 8,500 people at the Hinkley Point C site. This gives just an idea of the size of the project, with the corresponding opportunities for companies such as KAEFER that supply specialist industrial services.
“All we can do and continue to do is deliver professionally,” says Ferrand. “For us, it’s simply about providing the highest levels of workmanship and skill under challenging site conditions.”
What started with several layers of perfectly applied paint has now developed into a working relationship involving innovative access and even more complex surface protection, as well as precision ductwork.
Given that the UK government is planning to develop a nearly identical version of Hinkley Point C at Sizewell, an existing nuclear power plant within EDF fleet. This is a sizeable opportunity for KAEFER and one which will continue to showcase the company’s competence in challenging industrial projects. Down to the last layer of paint.