CNC Plasma cutters are a type of industrial machinery used to produce precise, custom die cuts in sheet metal, mild steel, and other electrically conductive materials such as aluminium. The key benefit of a plasma cutter is its ability to cut in complex shapes and patterns, including curves, straight edges, spirals and more. To be sliced using the plasma cutter, the material must have a thin, flat surface as the plasma will not be able to slice through objects after a certain thickness. CNC stands for Computer Numerical Control, meaning you will be controlling the cutting capabilities of the machine via a control panel, rather than manually slicing through materials. Digital control makes CNC Plasma cutter machines perfect for achieving consistent, repetitive custom shapes in sheet metal whilst retaining almost perfect accuracy throughout the operation.
How does a plasma cutter work?
Plasma occurs when gas is heated so significantly that it becomes ionised and electrically conductive. It transitions the gas to a new state of matter equivalent to ice transforming into a liquid form (water) when heated. A plasma cutter machine utilises the immense energy stored in plasma and transfers it to a conductive material such as steel or aluminium. The heat creates a clean, rapid, and precise cut in the material. Gases used by the cutter can include Oxygen, Nitrogen and Argon, but will vary depending on the project materials and applications. These gases are stored in large industrial tubes near the machine. When the plasma cutter is active, gas is forced into the highly pressurised nozzle whilst an electric arc is introduced from the power supply. Combining these two forces creates the plasma cutting jet, with temperatures greater than 20,000 Celsius. The piercing capacity of machines can also vary from 16mm thick all the way up to 50mm. The high pressure of the jet allows it to cut curved and custom shapes into far thicker material than other sheet metal slicing machines.
What a plasma cutter looks like?
Industrial plasma cutters are large rectangular table-like machines, with the cutting surface (AKA cutting bed) facing upwards. The plasma cutting torch nozzle is positioned to face down and opposing to the cutting surface to achieve the most accurate and clean slices. The nozzle arm is attached to two beams that allow the arm to slide vertically and horizontally respectively. This gives the cutter range across the full table and means it is not fixed in one position like larger slicing machines such as guillotines. Accompanying the cutting table is a large standing control panel with a monitor that allows for the 3D graphical input of shapes for cutting. To create any pattern or shape with the plasma cutter, a file must be uploaded to the control panel with accurate dimensions and specifications. Cutting beds can range in size from 1.9m in length, all the way up to 4.5m; for larger, longer sheet metal operations.
Wet vs dry bed plasma cutters
Industrial plasma cutters can be split into categories of waterbed and downdraft (AKA drybed.) Waterbed systems have a cutting surface that is covered in water, the sheet metal sits on thin horizontal metal slats that the water sits in-between rather than one entirely flat surface. This technique is historically used for plasma cutters, however, modern technology allows some machines to raise and lower the water level. This allows the sheet metal to be entirely submerged or above the water entirely. So, what does the water do? When cutting plasma in water, it captures and filters smoke particulates and dust that is generated during the cutting process and removes any chance of heat distortion on your cut materials. This results in cleaner slices overall. However, the downside to this type of table is the upfront cost – and it is not suitable for slicing aluminium. Choosing the right surface or ‘bed’ for your plasma cutter will depend on what materials you will mostly be cutting with.
Sheet Metal Solutions
Does your warehouse need a plasma cutter? Or, does your plasma cutter require repair or maintenance? ACRA Machinery supplies industrial sheet metal machinery to cater for all your sheet metal fabrication needs, including CNC Plasma cutters. Find out more about the Escco ProCut Plasma and Durma Plasma cutter range. Whether you need slicing, bending, notching or more – ACRA has new and second-hand machinery available for purchase today. Not only that, but we offer maintenance and repair to your industrial machinery as well.