Kilometres of pipes manufactured to cool down the core of ITER

In the heart of ITER, the super-hot plasma will release extreme heat and neutron blasts to the components inside the device. The Vacuum Vessel will be covered by 440 tungsten tiles, creating a protective blanket of  600 m². Beneath it, pressurised cooling water will run to help the blanket withstand the loads and extract up to 736 MW of thermal power (in fusion power plants this heat will be used to produce electricity).

Europe will provide the blanket cooling manifolds, the kilometre-long network of pipes branching around the tokamak. In 2023, Fusion for Energy (F4E) signed a framework contract with three suppliers:  Dockweiler–Tecnalia–Leading, Altrad Babcock Europe, and SIMIC, competing to produce the different parts of the system. These include various types of pipe assemblies that will be attached to different areas of the blanket, like the inboard, outboard or port bundles.

Whilst the contractors are busy finalising the first bundle prototypes, F4E has prepared for the next stage by buying the raw material for the entire manifold. The task was entrusted to the German company Dockweiler and their supplier DMV, specialised in stainless steel pipes. Their factory lines in Northern Italy ran at full throttle and completed the order on time this week. In total, they manufactured 18 km of pipes – the 9 km that will be installed in ITER, plus spare.

The manifold pipes are designed to endure harsh thermal and electromagnetic stress. They are made of nuclear-grade stainless steel, chosen for its strength and resistance. DMV, a supplier for industries like nuclear, aerospace or natural gas, managed to meet the nuclear requirements and ultra-tight tolerances for the pipes.

“This project helped us raise the quality benchmark in our manufacturing processes. Our work for ITER with F4E is an invaluable experience to capitalise on, as we seek new opportunities in fusion,” explains Vincenzo Rigotti, Quality Manager at DMV. “There are few suppliers capable of producing such pipes to the quality and quantity that ITER requires. We have successfully completed this task and we are advancing with the delivery of the manifold” claims Houda Labidi, Technical Officer at F4E.

The last shipment from DMV is now on its way to Germany. Dockweiler will store and later distribute the pipes to the different suppliers. Once in their workshops, they will be welded and shaped into the intricate steel web to cool the ITER reactor.