Gas supply system:
The gas supply system consists on gas bottles containing high purity He,H2,D2. He, H2, D2 and He. Helium is used for ventilating the complete system, and H2 or D2 for fueling the extrusion cryostat. The system gives also the possibility of admixing small amounts of Ne to the fueling gas. That allows for example the investigation of how impurities are propagated into the targeted plasma.
Cryostat system: pellet production:
The cryostat system comprises two parallel systems, one for the extrusion cryostat and the other for the storage cryostat. Main caracteristics of the cryostat system:
- The temperature control is based on the pressure difference between the cryostates in the liquid-helium circuit. It is possible to change the temperature of the extrusion cryostat by a controlled electric heating.
- The helium flux is controlled by pressure and flux measurements; the mean consumption is about 5 l/h per cryostat.
- Extrusion is performed with a hydraulic piston.
- All valves are controlled electropneumatically in order to ensure galvanic separation of the different circuits.
- A combination of three doubleacting pistons shifts the extrusion nozzle to 4 positions, namely for three pellet cross-sections and the closed position for fueling the extrusion cryostat.