PLASMA ARC TORCH HAVING AN HOURGLASS-SHAPED NOZZLE

摘要

A nozzle for use with a plasma arc torch having a first gas flow within the nozzle for engaging an electrode and generating a plasma and a second gas flow in surrounding engagement to the outer surface of the nozzle is disclosed. The nozzle includes an outer surface of substantially hourglass configuration in longitudinal cross-section so that the second gas remains in close contact with the outer hourglass surface of the nozzle to provide efficient heat transfer from the nozzle to the surrounding second gas flow.