Construction of nozzle for plasma cutting torch

摘要

A plasma cutting torch comprising: a gas current generator having at least one orifice which is formed in a working gas passage defined between the outer peripheral surface of an electrode and the inner peripheral surface of a nozzle disposed so as to surround the electrode and which extends substantially in parallel relationship with the longitudinal axis of said electrode, wherein in case the restricted area of the orifice of the gas current generator is expressed by S5 and the restricted area of a nozzle orifice of the nozzle is expressed by S4, the relation between the two is expressed by S5>/=S4. The plasma cutting torch is further provided with a generally cylindrical space portion formed on the upstream side of the nozzle orifice defined in the leading end portion of the nozzle and having a diameter larger than the diameter of the nozzle orifice.