Arc cutting is a process in which the heat of the arc, which glows freely between the electrode and the metal being cut, melts and fuses the metal in the cutting gap. Consumable or non-consumable electrodes can be used in the arc cutting process. The metal and slag from the combustion reaction, molten by the heat of the arc (at a temperature of 5,000-6,000 ℃), are ejected from the gap by the pressure of the arc or by the pressure of the additional gas supplied to the cutting area.
The basic types of arc cutting are:
- arc-air cutting with a graphite electrode – which involves melting the cut metal with the heat of a glowing arc between a graphite electrode and the cut area and blowing the molten metal out with a strong stream of air.
- oxy-arc cutting – which involves the ignition of an arc between a tubular covered electrode through which oxygen is passed at a suitable pressure.
- manual arc cutting with a covered electrode – where the metal in the gap is molten by the heat of the arc.