EXPORTED TO: China, Plasma Laboratory, Modern Physics Dept., University of Science & Technology of China, Hefei

8 barrel pellet injector for HT-7 tokamak (IPAS, Hefei, China) is a compact gas gun for injection frozen hydrogen or deuterium pellets into plasma. The pellets are formed inside the barrels simultaneously by in-situ technique. However, every pellet can be injected independently at arbitrary time. All barrels are equipped by fast electromagnetic valves attached to a common heat exchanger cooled by helium vapor. A special gate valve is used to close all the barrels before fuel gas admission. Pellet injection cycle takes approximately 3 minutes. Diagnostic chamber of this injector is equipped by pulse flash and photo camera for pellet registration.

Propellant gas


Gas pressure

7 MPa

Pellet material

hydrogen, deuterium

Pellet size: 

2 barrels: 1 mm 1 mm (L)

2 barrels: 1.2 mm 1.2 mm (L)

4 barrels: 1.5 mm 1.5 mm (L)

Pellet velocity

1 1.4 km/s

Photo flash

70 ns