Plasma cutters are machines used to cut various types of metals that can conduct electricity. With a plasma cutter, an operator can cut metals in complex or simple shapes. You can use a plasma cutter to create bevel edges, different radius holes, markings, and gouging. If you can’t use methods such as laser, water jet, or oxy-fuel cutting for one reason or another, then plasma cutting is the best alternative. Cutting metal using a plasma cutter is also cost-effective, unlike other methods of cutting metals. Many who prefer this metal cutting tool are those working in metal production industries, DIY applications, and trade. Large scale farmers also use it to repair broken farm equipment.
How Does Plasma Cutting Work?
Gas is turned into plasma when electrons in the gas molecules break free from the nucleus as gas is exposed to very high temperatures. Cutting metal using plasma involves directing the plasma torch to the workpiece or the metal you want to cut. Let’s now look at the pros and setbacks of using a plasma cutter.
Benefits of Plasma Cutting Systems
- A plasma cutter is a good option for cutting conductive metals such as non-ferrous alloys and stainless steel. Cutting stainless steel and non-ferrous alloys using oxy-acetylene cutting will give you a high-quality edge and finish.
- Plasma cutting has portable versions that can be carried around since it’s lightweight. The portable version is used in manual cutting.
- Just like other methods of cutting metal, automation versions of plasma cutters are also available. To cut complex shapes of metals at high speeds, we have the CNC plasma cutting machines.
- A plasma cutter is a very powerful metal cutting device that can cut metals up to 6 inches in thickness.
Plasma cutting won’t work on nonconductive metals. If you want to cut metals that don’t conduct electricity, then the best option will be the water jet cutter or a laser cutter.
Safety Precautions in Plasma Cutting
- Risk of Electrocution
The operator stands a great risk of being electrocuted since plasma uses a lot of electric power voltage and output. To prevent getting shocked, the person operating the plasma cutter must at all times wear proper protective gear or PPEs. These include rubber gloves, which should be worn inside the welding gloves. The working site should be free of any open channel fluids or water, and all cables should be checked before work begins.
- Skin and Eye Protection
When using a plasma cutter, harmful rays such as infrared and ultraviolet are produced. To protect the operator’s eyes from these rays, he should wear a face shield fitted with proper lens shade. The skin should also be protected from molten metal and fumes by wearing welding gloves, a welding apron, and proper safety shoes.
Types of Plasma Cutting
In plasma cutting, different types of gases are used on different kinds of conductive metals. When cutting carbon steels, oxygen or compressed air are used. Cutting stainless steel will require gases such as nitrogen or argon. Plasma cutting performance is optimized using a dual gas system that allows the operator to run on separate plasma and shielding gases. He can use a combination of these gases: Air/Air, O2/Air, N2/Air, N2/CO2, Ar-H2/N2.
Moreover, shield gases are used to cool plasma torches. For high power applications, there are liquid-cooled torches for longer lifespans and maximum cooling. A flow switch is a vital device while using a plasma cutter.
- Onboard compressors
For lighter cutting applications, plasma cutters are also available with integrated air compressors. If you want to carry them around to do remote jobs, you can do so since these variations of plasma cutting are lightweight.
- CNC machines with water bed:
Fumes emissions pose a major health risk when using plasma cutting. Plasma cutting on CNC machines have alternative fume extraction systems. Plasma cutting using CNC machines is done with water covering the workpiece. It can also be done with water placed under the workpiece. This is a cheaper way to get rid of harmful fumes. Besides removing fumes, the water bed also reduces the noise caused by the plasma cutter. When cutting thin metal underwater, distortion is also minimized.
- Arc/Plasma start
The two main types of arc starts include pilot arc or touch. In the pilot arc, contact between the nozzle and the workpiece is unnecessary since there is an arc in the plasma nozzle. On the other hand, when using a touch arc start, the nozzle has to contact the workpiece to start the arc.
To get the best-finished metal products, you need to invest in proper metal cutting equipment. Plasma cutting offers polished products when welding or cutting metals. However, to get the best out of metal cutting equipment, you also need to invest in the right flow switch.