Metal is hard. It takes a lot of force to bend or dent it and even more to break it. That is the reason we use it to build things that need to be sturdy and strong. When it needs cutting, we use special tools. Foremost among these is the plasma cutter. The extremely hot plasma generated by a plasma cutter quickly and easily cuts through metal.
Working with tools that can reach temperatures hot enough to cut metal brings great danger, though. So how is this heat managed?
The Reason Why Plasma Cutter Gets Hot
Plasma is the state of matter between gas and liquid. It is the substance that flames themselves consist of. In the case of a plasma cutter, the plasma is created by feeding an electric charge through a gas.
The cutter’s nozzle fires a tight jet of hydrogen, oxygen, nitrogen, or argon toward a cutting surface. As the gas flows, a current passes from the torch to the cutting surface, superheating the particles of the gas. These superheated particles begin interacting in a way that changes the nature of the gas to that of plasma.
This jet of plasma instantly reaches temperatures that can completely obliterate anything it comes in contact with. When aimed at a piece of metal, it quickly melts through, leaving behind a clean, neat cut.
Plasma Jets Heat Temperature
The temperature of these jets is around 25,000 degrees Celsius or about 40,000 Fahrenheit. To put this in perspective, a typical oxy-acetylene gas torch burns at about 3,200 degrees Celsius, making plasma torches almost ten times hotter. More terrifying still, the sun’s outer atmosphere burns at just over 3800 degrees Celsius. Plasma cutters burn at six and a half times the temperature of the sun’s outer atmosphere.
Using a device that burns hotter than the sun in a confined area is ridiculous, yet very human. Creating an arc of that temperature also requires a lot of electricity, making for a very dangerous setup. This is why you should take adequate safety measures before using one.
Plasma Cutter Basic Safety Requirements
As with any workshop environment, there is a set of personal protective equipment that every plasma cutter operative must wear. This set includes:
Coveralls
A full-body, heat-resistant outfit is the best option. Long sleeves and trousers protect the limbs from potential debris and heat exposure. These should also be form-fitting, as loose clothes pose many other risks.
Boots and Gloves
Being able to correctly and safely control the torch is just as important as the gear. Safety gloves and boots – thick leather gloves are ideal as they protect the hands and allow for full dexterity of the fingers. Protective boots are also essential, as the chances are good for your feet to be beneath what you are cutting. Still, at the barest minimum, every body part must be covered while using a plasma cutter.
Welding Helmet
The plasma jet coming from a torch will be hot and bright. To protect the eyes from light, heat, and potential gas fumes, you should wear a welding helmet.
Experience
You cannot buy experience from a PPE store or catalog, but it is just as important. No one should handle a plasma cutter alone if they have never used one or anything like one before.
Prior experience with other cutting tools is useful, as it will impart correct cutting practices like stance, angle cut, and body position. Inexperienced operators should only use a plasma cutter under strict and careful supervision.
Other Things to Keep In Mind
Beyond the PPE requirements, other safety devices and techniques are necessary for any plasma cutter job. Basic considerations such as keeping the area clear of other untrained personnel, excess debris and litter, and hazards that can be caught in tools are obvious but vital.
- Use the right tool for the job. Always ensure the torch is the correct size for the job. It must have enough power to cut through the metal but not so much as to become unwieldy. Bigger rarely means better when it comes to plasma cutting.
- Check the nozzles, tips, and gases. Wear and tear on your tools can lead to disaster when unchecked. A weakened or loosened torch nozzle could spell trouble if used using the wrong gas for the job. Change anything that looks worn, and only use new parts when in doubt.
- Stay away from water and mind the power. It will be tempting to keep water handy as a potential deterrent for flames or burning, but this is a terrible idea when it comes to plasma cutters. Remember, plasma torches run on high currents of electricity. Any amount of water in the vicinity of your plasma cutting table poses a deadly threat from electrocution or could cause the user to slip. It also pays to keep the torch’s power source and wires clear of debris or from dragging on the ground.
- Turn it off when not in use. Only run the torch for as long as the cutting happens. Shut it down as soon as it is done.
- Keep the torch covered and allow it to cool. Finally, each plasma torch operates under a safety box or case. This must be kept on at all times while using the torch, as it adds an extra layer of protection. It also keeps the cutting area clear of contaminants and contains any debris from the cut. Even after the cut is complete, allow the torch to cool fully before attempting to dismantle it.
It stands to reason that a tool that burns hotter than the sun requires a lot of safety and precaution. Plasma torches can very easily become extremely dangerous when handled incorrectly or inexpertly. Whenever you use one, take all the safety measures to safeguard your and your coworkers’ health.
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