Abstract: The present disclosure is directed to a coaxial cannula assembly including an infusion tube defining a return lumen and having a proximal end and a distal end. The distal end of the infusion tube includes a plurality of infusion openings and a flow restriction member positioned between the plurality of infusion openings and a distal tip of the infusion tube. The cannula assembly also includes a drainage tube co-axially aligned with the infusion tube and having a proximal end and a distal end. The distal end of said drainage tube includes a plurality of drainage openings and a length of the drainage tube is less than a length of the infusion tube. The cannula assembly further includes a drainage lumen defined by a space between said infusion tube and said drainage tube.

Abstract: Embodiments of the present invention include systems and methods of using a plasma arc torch to cut holes and contours in workpieces having varying thickness and material properties. The systems and methods of the present invention allow for the cutting of holes and contours without the need for using secondary processing by using particular overburn, tail out and/or cutting parameters.