A plasma cutting torch is commonly used in industrial environments for cutting a wide variety of materials.
Usually, handheld plasma torches could easily cut through metal pipes, straps, sheet metals, bolts etc. It can also be used as an excellent gouging tool for removing defective welds.
Using a hand torch requires skilled labour, and there is no guarantee that the cut will be precise as per the required dimension.
Besides for bulk production, using a handheld plasma torch will hike up the labour charges.
This is precisely the reason why a CNC plasma torch is used.
Process of plasma cutting
In this process, an accelerated jet of hot plasma cuts through electrically conductive materials. The most common materials that can be cut with a plasma jet are aluminum, brass, copper, stainless steel, iron and other conductive materials.
This method is widely used in the manufacturing industry, industrial construction, automotive repair and restoration, salvage and scraping.
High precision and speed are one of the notable advantages of this method, making it apt for use in a large scale manufacturing industry.
The cut is achieved by creating an electrical channel for ionised and superheated gas which will turn into plasma.
Compressed gas such as oxygen, inert gas or air (depending on the material to cut) will be blown to the workpiece through a nozzle.
An electric arc will be formed ionising the gas, creating an electrically conductive plasma channel. As the current form, the cutting torch flows through the plasma extremely high temperature is produced to melt through the workpiece.
A closed-circuit is achieved through the workpiece back to the plasma cutter through an earth terminal.
What is a CNC plasma cutter?
CNC plasma cutters are machines specially designed for cutting operations. The device is fitted with a plasma torch guided by the central computer to cut as per the desired path.
Different types of CNC plasma cutters
CNC plasma cutters are available in different types based on the requirement. The three main types are 3D/3+ axis,2D/2 axis, tube and section CNC plasma cutters
1. 3D/3+ Axis
This machine is best suited to cut on angles, making it very efficient in creating countersunk holes and chamfer edges of profiled holes.
The machine can rotate on a third axis and is most commonly used to cut flat profiles. Although it cannot move on a 90-degree angle, it allows cutting the edges at an angle of lower degrees.
2. 2D/2 Axis
This machine is best suited to produce 90 cuts on metal surfaces and penetrate metal plates up to 150mm thick.
3. Tube and Section
Just like the name suggests, this is used to process piping, tubing and long sections of material.
The cutting head is placed stationary but can be tilted or rotated depending on various cutting angles.
Advantages of CNC plasma cutting
- Works great for cutting electrically conductive materials.
- Excellent performance in small, medium and mild steel thicknesses.
- Operation of one or more burners depending on the series.
- Plasma cutting works underwater. This helps to ensure very low heat exposure and low noise level at the workplace.
- Can be used to cut high strength materials with low heat input.
- Cutting speed is 10 times more than oxy-fuel.
- The process can be fully automated.
- Extremely high precision cuts can be achieved.
The article is a part of our comprehensive guide on CNC machines.