Patent ID: 6452129
Filing Date: 2002-09-17
Classification: H05H

Abstract:
A swirl flow plasma arc torch comprising an elongated electrode having an open front end; a nozzle forming a plasma discharge opening which is coaxial with the electrode; a mounting arrangement for the electrode; the electrode, the nozzle and the mounting arrangement defining a swirl chamber between the electrode and the nozzle and an annulus concentrically surrounding the electrode and in fluid communication with the swirl chamber, the annulus terminating in a closed aft end which is spaced rearwardly from the front end of the electrode; and a plurality of plasma gas injection ports for directing a plurality of plasma gas flows into the annulus generally tangentially, all gas injection ports being located proximate the aft end of the annulus so that plasma gas from the ports spirally advances along the annulus and past the swirl chamber into the nozzle discharge opening, the annulus and the injection ports being positioned and dimensioned to prevent particulates entrained in plasma gas recirculating through the discharge opening towards the electrode and the annulus from reaching and abrading surfaces defining the annulus.