Plasma Cutting Systems

Plasma is the fourth state of matter. It consists of ions, positively charged atoms, negatively charged ions (electrons) and positively charged molecules. It also contains neutrally charged atoms. Plasma is a good conductor of electricity. Plasma exists at very high temperatures and is used by plasma cutting systems to cut metals.

Plasma Cutting Systems

Let us see how plasma cutting systems work? A gas is released through a very narrow opening, thereby increasing its high pressure. Before the gas escapes, an electrode is placed in its way that passes an electrical current through the gas. The gas atoms on being stimulated by the electric current produce positively and negatively charged ions. These ions collide with each other and the rest of the gas atoms to produce more ions. In no time, the gas reaches a superheated state or plasma.

Plasma Cutting Machine

Plasma cutting systems are nothing but an electrical circuit that have an electrode acting as a negative terminal (cathode), and the metal sheet to cut, acting as the positive terminal (anode). The plasma jet is attracted towards the metal sheet and at this point, in the operation, can focus as much as 30,000 degrees Fahrenheit or 16,648 degrees Celsius of heat on the metal sheet and melts it. The narrow opening of the nozzle increases the pressure exerted by the gas which also blows away the melted metal, thereby aiding the cutting of the metal sheet. The plasma arc is kept thin and controlled with the help of shield gases.

A plasma cutter is provided with channels to release shield gases which exert pressure and control the plasma arc and keep the plasma jet directed on the metal sheet. Inert or semi-inert gases are used as shield gases to shield the area, where the plasma arc or jet touches the metal. The plasma cutter is also known as a plasma torch. Plasma cutting systems are available as manual and computer-controlled. Let's take a brief look at the latter type.