Research and Development on Wall Conditions of HL-3

Wall condition is very important for the ultra vaccum and clean wall in a Tokamak device. The research and development on wall condition subsystems in vacuum system of HL-3 have been introduced. The debugging process and characteristics of wall conditioning are described, and the operational scenarios of baking system and the Glow Discharge Cleaning （GDC） system are designed. The results of baking system, GDC system and radio frequency assisted GDC system are discussed, respectively. By using the developed wall conditioning and pumping system, the vacuum system of the HL-3 device has reached the expected goal. The minimum pressure is 2.4×10⁻⁶ Pa before first plasma.