Most people have heard about plasma cutting whether it is done manually by a simple plasma cutting unit or with sophisticated and high tech CNC plasma cutters. However, there is more to plasma technology than meets the eye and it is a very effective method for cutting metals. Let’s delve a little deeper into the world of plasma, to see what it is and what it can for the 21st Century business.
Plasma – Not Solid, Liquid, nor Gas
Did you know plasma (which cuts through steel plate) is not one of the three states of matter? Plasma is something different. Matter has the ability to change state when it is exposed to heat. For example, a pan of water (liquid) will revert entirely to steam (gas) if heated long enough. If you remove enough heat from water, it will turn into a solid block of ice and transfer from liquid to solid. Let’s take this example a little further to help explain what plasma is.
Once water becomes steam (gas) it is basically oxygen and hydrogen in gas form. When you continue to heat this steam it ionizes and eventually can conduct electricity, because this gas has turned into plasma. But this is not usually the kind of plasma used in modern CNC plasma cutters today. Many modern plasma cutters use hydrogen, oxygen, nitrogen, argon and other gases for increased cutting efficiency.
Plasma is hot. In fact, it is so hot it literally cuts through metal and it is a much cleaner process than simply using a welding torch. In order to superheat the plasma, it is exposed to a spark which is then fed by electric current. By utilizing electricity, it makes the plasma cutting more precise and adjustable. In order to produce an arc of such high intensity it may take AC current as high as ten thousand volts at two megahertz. To give you an idea how high this is, standard house current is from 110 to 130 volts at a frequency of 60 hertz.
Adding Computer Technology to Plasma Cutting
Plasma cutting can be performed manually but is far more efficient when it is done with a computer operated machine. With CNC technology (the same technology which makes automated machining possible) cutting can be very accurate and extremely efficient. Modern CNC plasma cutters are very fast and can hold up to a great deal of use in the fabrication industry.