to - chi null for oxygen arc plasma cutting

摘要

PURPOSE:To increase the cooling effect of a 1st nozzle and to obtain a beautiful cutting face by forming a flange like projecting on the outer periphery at the tip of the 1st nozzle tautening a plasma stream and guiding the air for cooling to the outside direction from the parallel direction against a plasma gas injection direction. CONSTITUTION:An oxygen gas is injected as a tautened plasma gas from the plasma gas injection port 12a of a 1st nozzle 12. The flange like projection 12b in the circumference direction is formed on the tip outer face of the 1st nozzle 12, the air 15 for torch cooling is passed to the gas passage formed in the space with 2nd nozzle 13 and discharged in the outside direction at right angles with the plasma gas injection direction. The air 15 for cooling the torch is therefore collided with the flange projection 12b of the 1st nozzle 12 to increase the cooling effect of the 1st nozzle and to extend the service life. The oxygen plasma stream of the oxygen gas 14 injected from the plasma gas injection port 12a of the 1st nozzle 12 is not disturbed by the air 15 for cooling the torch nor the air is mixed and a stabilized oxygen plasma is fed to enable to obtain a beautiful cutting face.