High-Speed Imaging of Pilot Arcing and Piercing in PAC

In this paper, high-speed camera imaging of pilot arcing and piercing process phases in plasma arc cutting (PAC) with dual gas torches have been investigated using mild-steel and stainless-steel plates. The technique has provided new insight of the PAC process, and some interesting phenomena have been highlighted, such as the trajectory and velocity of hafnium particles emitted from the electrode during pilot arcing and the effect of nonperfectly aligned consumables (shield-nozzle) on inducing destructive piercing.