| 摘要 |
PROBLEM TO BE SOLVED: To provide a plasma arc welding system capable of instantly detecting that a plasma nozzle starts to melt.SOLUTION: The plasma arc welding system A1 executes plasma arc welding by using a torch 12 including a nonconsumable electrode 121 and the plasma nozzle 122 for surrounding the nonconsumable electrode 121. The plasma nozzle 122 comprises a plasma power circuit 41 for impressing plasma voltage Vp between the nonconsumable electrode 121 and a base material W by forming a nozzle opening for restricting a plasma arc generated between the nonconsumable electrode 121 and the base material W, a voltage detection circuit 46 for detecting the plasma voltage Vp between the nonconsumable electrode 121 and the base material W and a deformation detection circuit 47 for generating a deformation detection signal Sf when detecting deformation of the nozzle opening. The deformation detection circuit 47 detects the deformation of the nozzle opening based on the plasma voltage Vp detected by the voltage detection circuit 46. Such a constitution can instantly detect that the plasma nozzle 122 starts to melt. |
