How does a plasma cutter work?
In this article we will explain how a plasma cutter works step by step.
Essentially a plasma cutter is used for cutting through metals both ferrous and non ferrous. It uses a high speed jet of ionised gas generated by an electrical arc.
The arc is passed through a small nozzle creating a concentrated and extremely hot stream that melts and blows away the metal resulting in precise and efficient cuts.
But what exactly is Plasma?
Lets first go back to arc welding as this will help explain what the arc is.
When we weld metals, we are joining two of the same types of metal together. Traditional stick or arc welding is the simplest form of welding as it only requires a stick (electrode) tot eh base materials. The welding machine produces a high voltage electrical current which is passed through the electrode to the base material (only ferrous material can be welded with an arc welder). Intense heat is produced by the arc of electrical current and melts not only the electrode but also the material that is to be joined. This created a molten pool of metal and as it cools , a solid and fused metal joint forms.
There are a number of types of welding such as MIG, TIG which essentially use the same principals of arc however are more complex making it harder to produce a good weld, however these types allow the welder to join non ferrous and alloy metals together.
As we can see, an arc welder produces an arc of electrical current between the electrode and workpiece, similarly so does the Plasma cutter. However not only does it use electricity , it uses a high speed jet of ionised gas passed though a very small nozzle which focusses the stream.
A high frequency electrical arc is established between the nozzle and the workpiece . The arc creates heat and ionised the gas passing through the nozzle. It is typically compressed air (this is why it is important to have good quality air compressor when considering buying a plasma cutter) r sometimes Nitrogen though less common. The intense heat breaks the gas molecules into positively charged ions and frees electrons, forming a high- energy plasma stream. This electrically conductive plasma can then be directed towards the material , melting and cuttings it with precision.