A mock-up of a tritium pellet injector for ITER

The ITER tokamak is to be equipped with a pellet injector for plasma fuelling. A tritium compatible pneumatic pellet injector with a screw extruder has been designed, tested with protium, and is under installation for testing at the experimental tritium loop in the Russian Nuclear Center in Sarov. The rectangular rod 3×4 mm2 from condensed protium was extruded within 1500 s at rate of ∼15 mm/s. Pellets ∼3 mm in size formed from the rod were accelerated up to 500 m/s by helium under a pressure of 1 MPa with an injection frequency of 1 and 2 Hz. The main injector subsystems and the current status of the work are described.