Systems and methods for stabilizing plasma gas flow in a plasma arc torch

A nozzle of a plasma arc torch, the nozzle comprising:

• a shell including a body having a plasma exit orifice disposed therein, an internal shell surface, and an external shell surface;
• a liner having an internal liner surface and an external liner surface, at least a portion of the external liner surface surrounded by the internal shell surface;
• and
• an isolation chamber defined by at least a portion of the shell, the liner, and a sealing surface located between the liner and the shell, the isolation chamber having a common inlet and outlet being fluidly connected to a plenum gas flow passage coupled to the plasma exit orifice via a nozzle plenum, the isolation chamber being dimensioned to maintain a volume of substantially stagnant gas received from the plenum gas flow passage, thereby reducing surges in the fluid pressure in the nozzle plenum.

A method of reducing fluid pressure surging in a nozzle plenum that is located between a nozzle and an electrode of a plasma arc torch, the method comprising:

• supplying a plasma gas into a proximal end of the nozzle, the plasma gas is adapted to flow into the nozzle plenum and distally exit the nozzle via a nozzle exit orifice;
• diverting a portion of the plasma gas to flow into an isolation chamber via a common inlet and outlet of the isolation chamber, wherein the portion of the plasma gas is substantially stagnant in the isolation chamber;
• and
• reducing the fluid pressure surging in the nozzle plenum based on the diverting.