The manufacturing of the ITER Poloidal Field coils has started
CNIM technicians supervising the manufacturing of the European Poloidal Field coils in F4E’s Facility, Cadarache
The team of engineers from F4E, ASG and CNIM,
working in Europe’s industrial facility on the ITER site, and their colleagues in
ASIPP, the Institute of Plasma Physics of China’s Academy of Sciences, have
officially started manufacturing the Poloidal Field (PF) coils assigned to
Europe for the biggest fusion device –ITER. ITER will operate with six PF
coils. Europe is responsible for five of them and through a collaboration
agreement with China one will be fabricated in ASIIP. The remaining coil will
be delivered by Russia.
After having successfully completed the winding
tests using lengths of dummy conductor, the technicians have started unspooling
the “real” conductor and inserted it in the machines to produce the impressive
magnetic rings that will control the shape and stability of the super-hot plasma.
In ASIPP, the winding of the first Double
Pancake (DP), which consists of two layers of conductors wound in the shape of massive
pancakes, started in mid-March and has been completed. Works on the two Helium inlets
at the inner joggles, from where Helium will circulate in the conductor to
lower its temperature to freezing levels so as to make the coil superconductive,
have been concluded. Carefully milling a hole in the jacket, without damaging
the superconducting strand underneath, and welding a pipe to feed the helium
into the conductor, have been some of the additional delicate works that needed
to be performed. This weld has then been X-Rayed and leak tested to ensure that
no Helium can escape through the weld. Subsequently, the Helium inlet
insulation has then been wrapped around the inlet. On average, the winding of a
DP is expected to take 4-5 weeks each.
of the first Double Pancake of Poloidal Field coil 6 has been completed, ASIPP,
After a series of rigorous dimensional checks,
in order to check whether the shape and dimensions of the component are in
compliance, the component will be transferred to the terminal assembly area. The
DP will enter its final stage of fabrication by going through Vacuum Pressure
Impregnation, where the necessary vacuum will be created to inject the epoxy
resin and cure the insulation.
Meanwhile, a few weeks ago in F4E’s PF coils
facility, CNIM has already started winding the conductor of the fifth PF coil
and the first DP is expected to be completed by the end of May. When the first
layers will be completed, the team of technicians will proceed with the
installation of the Helium inlets and perform the same steps as in ASIPP.
lengths of conductor unspooled for the manufacturing of the Poloidal Field
coils in F4E’s facility, Cadarache
The good collaboration between F4E, ASIPP and
their industrial partners, has been fundamentally important in making good
progress in a co-ordinated way. The engineers and technicians supervising the
works are witnessing the moment they have all been waiting for: the winding
tests are over and the coils are being manufactured for real!