What are CNC plasma cutters used for?

CNC plasma cutting is a process that cuts electrically conductive materials by means of an accelerated jet of hot plasma. Typical materials cut with a plasma torch include steel, aluminum, brass, and copper, but other conductive metals can also be cut. CNC plasma cutters are commonly used in fabrication shops, automotive repair and restoration, industrial construction, and salvage and scrap operations. Because of their fast cutting speeds, high accuracy and low cost, CNC plasma cutters are used in a wide range of applications, from large industrial CNC applications to small hobby stores.

The basic CNC plasma cutting process involves creating an electrical path of superheated ionized gas, i.e., plasma from the CNC plasma cutter itself, through the workpiece to be cut, thus forming a complete circuit that returns to the CNC plasma cutter through a grounding clamp . This is accomplished by means of compressed gases (oxygen, air, inert gases, and other gases depending on the material being cut), which are blown through a focusing nozzle at high velocity into the workpiece. An electric arc is then formed within the gas, between an electrode close to or integrated into the gas nozzle and the workpiece itself. The arc ionizes some of the gas, thus creating a conductive channel for the plasma. As the current from the torch travels along the plasma, it provides enough heat to melt the workpiece. At the same time, most of the high-speed plasma and compressed gases blow away the hot molten metal, which separates, i.e. cuts, the workpiece.

Because CNC plasma cutters produce a very hot and very localized "cone" for cutting, they are useful for cutting curved or angled shapes in sheet metal.Some CNC plasma cutter manufacturers make CNC cutting tables, and some build the cutter into the table. The CNC table allows the computer to control the torch head, producing a clean, sharp cut. Modern CNC plasma machines are capable of multi-axis cutting of thick materials, allowing for complex welds that would not otherwise be possible. For thinner materials, CNC plasma cutting is gradually being replaced by laser cutting, largely due to the superior hole-cutting capabilities of laser cutters.

Since the introduction of CNC plasma cutting machines in the early 1980's, this technology has dramatically increased productivity in a variety of industries. CNC plasma cutting machines are used by many shops to create decorative metalwork. Examples include commercial and residential signs, wall art, address signs and outdoor garden art.