Plasma Cutting Nozzle

The orifice in a torch cutting nozzle is designed to constrict the arc to a specific diameter without the arc touching the nozzle. The plasma gas provides a thin boundary layer of cool gas between the arc and the nozzle. If the current level is to high or gas flow is to less the arc may contact the cutting nozzle causing a double arc which will damage the nozzle by increasing its diameter disproportionately. Thus proper constriction will not be achieved resulting in a poorly focused arc and a bad cut finish. If a nozzle is gouged on the inside or outside or if the hole is worn out of round it should be replaced--otherwise it may be reusable. When the nozzles wear out cut quality deteriorates . Gouges on the inside indicate that too high current or inadequate air flow was used. Touching the job , piercing or cutting too fast can damage the nozzle from the outside .