Dual flow nozzle shield for plasma-arc torch

摘要

A dual flow nozzle shield of a plasma-arc torch positioned in front of a torch end cap and secured in such position by a shield retaining cap. The shield is made from lava or wonderstone ceramics or copper materials. The shield has three support feet for resting on a counterbore section of one end of the cylindrical torch end cap and for providing space between the shield and the shield retaining cap for gas bypass around the outside of the shield. An alternate embodiment of the nozzle shield comprises a plurality of notches around the perimeter of the shield for the bypass gas to pass through. A primary gas enters the shield with a portion of the primary gas going through an orifice in the center of the shield. Both embodiments have a backflow or bypass portion of the primary gas that does not go through the orifice, but instead goes back up and through the space between the posts in one embodiment or the notches in the second embodiment and comes down over the outer side of the shield. This bypass gas is directed toward the arc, keeps splattering molten metal directed toward the arc, and keeps the splattering molten metal away from the front of the shield resulting in a better quality of cut, longer life of the shield and less cost for shield replacement.