Plasma cutting and welding machines melt areas with an arc and then use a high-velocity, high-temperature ionized gas to make cuts and fuse materials. The high-velocity ionized gas conducts electricity from the torch of the plasma cutter, heats the workpiece, and then melts the material. The high-velocity stream of ionized gas blows the molten metal away from the workpiece and severs the material. The arc’s contact with the working surface creates a high-heat circuit which can melt a section less than 1/16 in. (1.6mm) wide. The force of the plasma flow creates a fairly clean cut with little or no slag. With some plasma cutting machines, the plasma arc travels through the nozzle at a speed of up to 20,000 feet per second, and at temperatures as high as 30,000º F.

There are many different types of plasma cutting machines and equipment. Examples include plasma cutting torches, plasma torches, and plasma cutters. Plasma cutting torches use compressed air or nitrogen as the cutting gas. They provide narrow-width kerfs and use a water-cooled electrode. Plasma torches produce a high-temperature gas stream by passing the gas to be heated through an electric arc discharge. Typically, a plasma torch has two metallic, tubular electrodes so that the electrical arc flows between the negative and positive electrodes. Plasma cutters are suitable for cutting steel and other electrically-conductive materials. With a plasma cutter, the surface of the metal outside of the cutting area remains cool. Other types of plasma cutting machines and plasma cutting equipment are also available.

Plasma cutting machines are used in many applications. They provide high-quality cuts and fast travel speeds. Some plasma cutting machines are used in metal working, switch gear construction, and part fabrication applications. Others are used in the manufacture of heating, ventilation and air conditioning (HVAC) systems. A used plasma cutting machine is a remanufactured system that includes components and subassemblies such as torch holders, motor/gearboxes, operator control consoles, bearings and hoses, and cables. A CNC plasma cutting machine can be used to automate the material shaping process. Plasma cutting machines should adhere to American National Standards Institute (ANSI) standards.