How Hot Does a Plasma Cutter Get? (Real Facts + More)

It is fair to say that working in welding means working with some pretty hot temperatures. You know that. Everyone knows that. What everyone might not know is just how hot things can get while you’re working with a plasma cutter on a fresh aluminum beam or cutting into some stainless steel.

One of the most frequently asked questions about plasma cutters is: how hot does a plasma cutter actually get? based on some measurements, they can get as hot as 45,000 degrees Fahrenheit, or 25,000 degrees Celsius.

Intellectually, you know that the temperature required to cut into such tremendously strong materials has to be high. Even so, it can come as something of a shock to realize that those temperatures can top four, even five digits Fahrenheit.

How and why does plasma get so hot, how does the heat of a plasma cutter compare with some truly astronomical temperatures, and what can you do to make sure you can stand the heat safely?

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How Hot Is Plasma Cutter?

So given that, it’s worth wondering, just how hot can a plasma cutter get?

By some measurements, they can get as hot as 45,000 degrees Fahrenheit, or 25,000 degrees Celsius. That kind of heat is so immense that it’s obviously far too hot for you to expose yourself to – which is what makes it all the more mind-blowing that it’s possible to have that much heat at the touch of your fingers.

The same holds true for the brightness of the light generated by this awesome amount of heat and power. Just as you should never look directly at the sun, let alone a solar eclipse, you should never look directly at the flame produced by this kind of heat. The light produced by this kind of flash is comparable to those celestial bodies and can likewise lead to permanent eye damage.

To draw a further comparison, consider an oxyacetylene flame. These are the types of flames produced by welders which rely on oxy-fuel. By contrast, these are “only” 9,000 degrees Fahrenheit, or 5,000 degrees Celsius.

We’re not done with the hotter-than-hot comparisons. Both can give off incredibly bright light, but can plasma cutters rival the heat of the sun itself?

Yes – maybe. It depends on how you frame the question.

Plasma cutters are hotter than the surface of the sun which, on average, is about 9,940 degrees Fahrenheit, or 5505 degrees Celsius. However, the surface temperature of the sun can get up to roughly 45,000 degrees Fahrenheit, about equivalent to a plasma cutter. What’s more, the inner core of the sun where pressure is even greater can get even hotter, though obviously it’s a bit hard to obtain measurements there.

Even if we take the larger figure, however, even being comparable to the hottest temperature of the sun gives an idea as to just how hot plasma cutters are, and thus how much power and energy is unleashed every time you turn one on.

Think something like the Earth’s planetary core must be hotter still? Think again. Not only are plasma cutters hotter than the Earth’s core, it isn’t even close.

At its hottest, our planet’s core measures around 10,800 degrees Fahrenheit, or roughly 6000 degrees Celsius – incredibly hot in its own right, but nowhere near as hot as the maximum heat generated by the sun or a plasma cutter.

That isn’t all – scientists think that they may be able to someday get plasma heated up to temperatures as high as 10 trillion degrees Fahrenheit. Needless to say, you won’t be using temperatures that high to trace out ornamental napkin holders or stick fenders back on your car, but it is still pretty incredible to wrap your head around.

In short, when working with a plasma cutter, you’re literally harnessing the power of something capable of reaching temperatures higher than anything on Earth and comparable to the hottest point of the sun’s surface. If that makes you appreciate the tremendous amount of heat on display here, you need a cold shower to wake up!

How You Can (and Should) Stand the Heat

Needless to say, those temperatures are a bit too hot to deal with unprotected. Harnessing that much heat can feel like a superpower, and in Uncle Ben’s immortal words, “With Great Power Comes Great Responsibility.” As such, you’ll want to take some basic precautions when using plasma cutters.

For starters, you’ll want to make sure that you account for all that power in your electricity bill. Generating all that power isn’t easy, and it isn’t always inexpensive. While you can get a hobbyist plasma cutter for a few hundred dollars, these typically don’t reach the literally-astronomical temperatures produced by the hottest plasma cutters mentioned here. When using such units, make sure you can actually foot the bill.

You should also make sure to practice proper plasma cutter safety at all times. This includes:

Not always using the maximum settings. Sure, it may be fun to use so much power, but you rarely need to crank things up that high, and those higher settings up the danger as well as the amount you’ll have to pay in terms of electricity used.
Always wearing a proper welding helmet with darkened visors that are strong enough to protect you from sparks, flashes, debris, and any other dangers.
Wearing other protective gear. Your hands, arms, and legs should be completely covered with no skin showing. Make sure you are wearing gear that is heat-resistant and provides you free range of movement and – in the case of your gloves – a good, solid grip.

Properly harnessed, the immense heat generated by plasma cutters can feel truly out of this world.

What is Plasma?

Plasma is often referred to as the fourth state of matter, following solid, liquid, and gas. As a material’s temperature increases, it transitions from one state to another. For instance, a solid melts into a liquid and then evaporates into a gas. When a gas is heated even further, its molecules become ionized, breaking apart into electrons and ions. This ionized gas forms plasma, which contains both charged particles and neutral atoms.

Plasma cutting utilizes the intense heat generated by this ionized gas to cut through metal. The plasma cutter’s jet can reach temperatures of up to 25,000 degrees Celsius (45,000 degrees Fahrenheit), significantly hotter than other common cutting methods like oxyacetylene flames.

How Does a Plasma Cutter Work?

A plasma cutter works by creating an electrical arc between an electrode and the metal being cut. The arc ionizes the gas (often compressed air) in the cutting nozzle, converting it into plasma. As the plasma jet exits the nozzle, it focuses on the metal, creating a concentrated stream of extreme heat that melts the metal and cuts through it.

The speed and precision of plasma cutting make it a popular choice for various applications. It can cut through metals up to 200 inches per minute, making it an efficient tool for both small-scale projects and large-scale manufacturing processes.

Comparing Plasma Cutting to Other Cutting Methods

Plasma cutting stands out from other cutting methods due to its high temperature and speed. For example, oxyacetylene flames, which are commonly used for cutting and welding, reach temperatures of around 9,000 degrees Fahrenheit. This is roughly five times cooler than the plasma cutter’s flame.

Laser and water cutting machines, on the other hand, offer cleaner cuts without leaving any residue or dross. However, these machines are significantly more expensive, less portable, and cut at a much slower rate than plasma cutters. As such, plasma cutters remain the go-to choice for most workshops and professionals.

The Dangers of Plasma Cutting

Given the extreme heat generated by plasma cutters, safety is of utmost importance when operating these tools. The intense brightness of the plasma flame can cause permanent eye damage if looked at directly, so it’s crucial to wear appropriate eye protection. Additionally, the high temperature can cause severe burns if the operator’s skin comes into contact with the plasma jet or the molten metal.

Furthermore, the sparks and molten metal produced during plasma cutting can ignite nearby materials, posing a fire hazard. It’s essential to maintain a clean and organized workspace, keeping flammable objects at a safe distance from the cutting area.

Safety Measures When Using a Plasma Cutter

To minimize the risks associated with plasma cutting, follow these safety guidelines:

Ensure proper training and experience: Only trained and experienced individuals should operate plasma cutters. If you’re new to plasma cutting, seek guidance from a professional or attend a training course.
Wear appropriate protective gear: This includes heat-resistant clothing, safety goggles with side shields, a welding helmet, gloves, and sturdy shoes. Avoid wearing loose clothing or jewelry that could catch on fire.
Maintain a clean and organized workspace: Keep flammable materials away from the cutting area and ensure adequate ventilation to prevent the buildup of harmful fumes and gases.
Use caution with electrical equipment: Plasma cutters require a significant amount of electricity to operate, so make sure to use properly grounded outlets and extension cords. Also, avoid using plasma cutters near water sources to prevent electrical shocks.
Have a fire extinguisher nearby: In case of a fire, it’s essential to have a fire extinguisher within reach to quickly put out any flames.

Cooling a Plasma Torch

To prevent damage to the plasma cutter’s nozzle and electrode, it’s necessary to cool the torch periodically. This process typically involves using a coolant specifically designed to reduce high temperatures that could harm the equipment. The coolant is released onto the electrode’s back through a slim opening at high speed, ensuring rapid heat reduction and dispersion. Once the coolant has cooled the electrode, it moves on to cool the nozzle, swirling around its outer side to preserve the nozzle’s lifespan. The coolant then exits the nozzle and returns to the cooler, continuing the cooling process as long as the plasma cutter is switched on.

The Future of Plasma Cutting

As technology continues to advance, it’s likely that plasma cutters will see further improvements in their performance and safety features. One potential area of development is achieving cleaner cuts, similar to those produced by laser and water cutting machines. By doing so, plasma cutters could become even more efficient and versatile, solidifying their place as an indispensable tool in various industries.

Frequently Asked Questions

Can a Plasma Cutter Cut Rock?

Plasma cutters can cut through rock, but only if the rock conducts electricity. Non-conductive rocks will not be cut effectively, as the plasma arc would die upon contact with the rock. Plasma cutters are best suited for cutting conductive materials like metal.

What Gas Do You Need for a Plasma Cutter?

A plasma cutter’s flame is generated by a pilot arc being forced through a constricted opening filled with gas. Common gases used in plasma cutters include shop air, oxygen, argon, and nitrogen. The plasma gas flow is automated by the plasma cutting machine.

Is Lava a Plasma?

No, lava is not plasma. While lava is extremely hot, it is a form of molten rock ejected from a volcano, making it a liquid. Plasma is even hotter than the most energetic gas and has different properties.

Is Lightning Made of Plasma?

The central column of lightning, as it discharges, can be in a plasma gas state. The flow of electrons and positive ions within the lightning creates a temporary plasma state with very high voltage.

Conclusion

Plasma cutters are powerful tools capable of generating extreme heat, reaching temperatures of up to 45,000 degrees Fahrenheit. This intense heat allows plasma cutters to cut through metal with speed and precision, making them invaluable in various industries. However, the dangers associated with plasma cutting necessitate strict adherence to safety measures and proper training. By understanding the science behind plasma cutting and taking the necessary precautions, professionals can harness the power of plasma cutters to achieve impressive results in their work.