If you need a cutting system for specific materials and jobs, a plasma cutting version has to be considered. It offers a huge number of benefits for most fabrication and manufacturing operations, but also has a number of drawbacks that you need to take into account. By being aware of all these factors, you can make an informed decision and obtain the most suitable cutting system.
A plasma cutter is a thermal cutting device that is used to cut a variety of metals. It uses a plasma arc at extremely high temperature (generally from 11,000⁰C to 30,000⁰C) to melt metal along a cut line and then remove the molten metal from the workpiece. The system comprises a plasma torch with an electrode and nozzle, a power supply that delivers DC electricity at high amperage, a cutting bed on which metal is placed for cutting, a control system and a cooling mechanism to prevent the equipment from overheating.
Advantages of Plasma Arc Machining
Plasma cutting has become increasingly popular for many applications and in several industries because it provides a lot of benefits over other forms of cutting:
- Possibly the biggest advantage that a plasma cutter has is the precision of cutting that produces very clean and accurate cuts. This is especially true for a computer numerical controlled (CNC) system, where the machine is pre-programmed and the processing is automated. Precision is also taken to even higher levels by high definition (HD) models. Plasma cutting rarely produces irregularities or jagged edges, provided it is used properly on the correct type and thickness of materials. This is particularly important for detailed work or intricate patterns. It also means that little or no finishing is needed, which reduces processing time and cost.
- Speed of cutting is also a major benefit, especially for thinner metals, where plasma will cut 25 mm thick steel twice as fast as oxy-fuel equipment. The faster throughput significantly increases productivity levels, especially for high-volume production.
- Plasma cutters are powered by electricity and use gas, often compressed air or combinations of other gases. These are generally cheaper than those used for oxy-fuel cutting, keeping overall operating costs lower.
- The systems are extremely versatile, able to cut through a wide range of conductive metals including steel, copper, brass and aluminium. They can also handle very intricate cuts to produce complex shapes, making them ideal for medium-thickness metals compared to oxy-fuel.
- Lower wastage levels result from cleaner cutting, especially in automated CNC systems, where human error is reduced. Reduced re-work improves productivity and flow.
- Minimal heat exposure reduces warping and distortion, thanks to a smaller heat-affected zone. Dross is eliminated or easy to remove. This improves both the precision and the dimensional stability of finished items.
- With several easily replaceable consumables, plasma cutters tend to be cheaper and easier to maintain than laser and water jet models.
- Although plasma cutters use high electricity and extreme heat, they are safer to operate than laser systems, which require protective enclosures. Inert gases are also safer than stored oxy-fuel gases. Automation further improves safety by limiting operator intervention.
- A plasma cutter costs about one-third of an equivalent laser or water jet system. For cutting thicker materials, the price gap widens even further, and running costs remain lower, making plasma ideal for small to medium-sized companies.
Disadvantages of Plasma Arc Machining
Although plasma machines have many advantages, there are also some drawbacks:
- Plasma cutting is only suitable for conductive metals; non-conductive materials require other methods.
- Cutting depth is limited to about 64 mm for clean results. Thicker materials are better handled by oxy-fuel or water jet systems.
- Plasma systems are still a significant investment. Added features like power source and speed integration increase cost, so you need to match the machine to your workload. Financing can help offset upfront costs.
- The process is noisy, with levels between 90–120 decibels. Operators require effective ear protection.
- Plasma cutting produces fumes and gases, so ventilation and exhaust systems are essential. Operators also need masks.
- Bright light and sparks can harm eyes and skin, requiring protective clothing and filtered eyewear.
- Cut quality is generally excellent, but lasers and water jets may achieve higher precision in some cases. Thin metals under 3 mm may warp, though good torch height control helps mitigate this.
- Low-end, budget plasma cutters are often poor quality, with sub-standard components and software. These produce unreliable results, frequent breakdowns and short lifespans. Investing in quality equipment is essential.
Choosing the Right System
Getting the best plasma cutting system depends on carefully assessing your needs and finding equipment that matches them. We offer a wide range of systems, and can also custom-build solutions tailored to your requirements.
No single cutting system covers all jobs, but plasma is one of the most practical and cost-effective options available, offering long service life, speed, and safety. Many disadvantages can be minimised through correct system selection, automation, and operator training. Automation reduces errors and increases efficiency, while modern systems are designed with user-friendly interfaces.
We can provide the advice and support you need to choose the right system. Contact us today to get started.