F4E hosts meeting on mineral insulated cabling

F4E has hosted a meeting concerning mineral-insulated cables (MIC) — the cables for diagnostic systems inside the ITER vacuum vessel, which F4E is responsible for procuring. The objective of the meeting was to inform participants of an upcoming call for tender for the procurement of cabling for prototyping and to interview participant companies that produce cabling for nuclear environments to survey the solutions they already have available on the market and to learn more about their previous experience. In total, representatives of eight companies from France, Germany and the United Kingdom attended the meeting and showed a strong interest and eagerness in learning about ITER business opportunities.

ITER will be equipped with an extensive set of diagnostics inside the tokamak to measure plasma parameters. The plasma diagnostics will protect the machine from damage during operation, control the functioning of the machine and provide information for detailed studies of the physics of fusion energy production. A diagnostic system is typically made up of sensors and cabling inside the tokamak, transmission lines outside the tokamak and electronics. The sensors will measure various plasma characteristics such as the magnetic fields and current. The cabling inside the tokamak and the transmission lines will deliver these measurements to electronics located in a separate building, for digitisation and subsequent processing by the diagnostic software, to determine plasma parameters.

Approximately 9 000 cables of various types and lengths must be manufactured for the ITER machine. The cumulative length of the cables is estimated to be around 20 km. MICs have performed well in other fusion experiments because of their compatibility with the vacuum environment inside the tokamak and their robust construction. Although the ITER design specification has yet to be finalised, it is more than likely that MICs will be used inside the tokamak. The fusion plasma releases a large amount of heat and the diagnostic cables in the tokamak need to be able to withstand temperatures up to 500 °C. The cables are ‘lifetime’ components intended for ITER’s entire operating lifespan of 20 years. This is because there is no possibility of maintenance or replacement once the cables have been installed in the machine.

Following the information meeting, F4E’s immediate next steps include carrying out extensive testing using samples of cables from various manufacturers in order to determine if they are suitable for ITER.