| 摘要 |
PROBLEM TO BE SOLVED: To smoothly carry out plasma ignition based on gaseous argon. SOLUTION: Air is supplied to a main pipe 22 with a motor valve 44 closed and a motor valve 45 opened. A reaction furnace 8 is controlled to a prescribed pressure. Gaseous argon is supplied into a torch 1 by a prescribed quantity with a motor valve 48 opened. High frequency power is supplied to a high frequency coil 4 to ignite argon plasma. The motor valve 44 is gradually opened to gradually supply air into the torch 1, the high frequency power is increased and when the air quantity reaches the prescribed quantity, the motor valve 48 is closed and the supply of gaseous argon to the touch 1 is stopped. The motor valve 45 is gradually closed, the high frequency power is further increased and steam is supplied to the torch 1 to generate thermal plasma of steam. When the steam quantity reaches a prescribed quantity, the supply of the air to the torch 1 is stopped. The prescribed quantity of fluorocarbon is supplied to the torch 1 from a fluorocarbon bomb 17. |
