How Hot does a Plasma Cutting Machine Get?

Last Updated on May 2022


You’ve seen welders cut metals using plasma machines and it made you wonder “What’s this technology all about?”

In fact, how hot does this machine get for it to cut metal with such ease?

These are excellent questions especially if you are a welder or intend to engage in this business.

Why not get the facts. Read on to find out more.

What is Plasma?

To properly understand how this machine cuts, we must first know what plasma is. In its simplest definition, plasma is actually the fourth state of matter. Does that sound far-fetched?

Like many other people maybe you are accustomed to the three states of matter as they were presented to you by your elementary and even high school instructors. You know about solid liquid and gas but the fact is there is another state of matter, a fourth state which is plasma. Let’s explain this briefly.

You know that for matter to change from one state to the next energy is involved. For instance, to change ice to water, the solid has to absorb some heat. This heat excites the particles and makes them freer this leading to the liquid state.

Increasing the amount of heat further changes the liquid to gas (steam). Have you ever wondered what would happen if the heat levels in the steam are increased?

This is where the fourth state of matter comes in; the gas particles become ionized and electrically conductive. That is where the matter becomes plasma.

So, now you know of the four states of matter: solid, liquid, gas and now plasma. But how does all this fit in cutting metals?

How a Plasma Cutting Machine Works

A plasma cutter works by sending an electric arc through a charged gas that is passing through a constricted opening. This gas can be nitrogen, oxygen, argon, shop air and so on. This action elevates the temperature of the gas to the point that the gas finally enters the fourth state of matter. It’s this high-speed super-hot gas that cuts through the molten metal. But how hot does it get?

How Hot Does the Plasma Cutting Machine Get?

To understand this, it’s important to remember facts. It takes 2 degrees Fahrenheit to change a solid into a liquid. It takes another 212 degrees Fahrenheit to change that liquid to gas.

These increments increase by well over 10,000 to change the gas into plasma. The plasma cutter spews jets reaching up to 40,000 degrees Fahrenheit or a whole 22,000 degrees Celsius. Simply said, that is how hot these machines can get. Yes, the jet quickly pieces through the work pieces and blows away the molten material.

These temperatures are, by all standards, insanely high. When you see a welder holding this tool and cutting metals in record time, know the kind of heat he is holding in his hand.

Components of a Plasma System

Basically, a plasma system has three major components as summarized below:

Power Supply

This is the source of power used by the system to supercharge and heat the gas. The power supply converts AC line voltage into a constant and smooth DC voltage that ranges between 200 and 400 VDC.

The Arc Starting Console

This circuit produces about 5000 VAC which produces the spark inside the plasma torch which in turn creates the plasma arc.

Plasma Torch

The function of this torch is to give proper alignment and cooling of the ingredients inside. The main ingredients necessary for plasma arc generation are the swirl ring, nozzle, and the electrode.

The Evolution and Future of Plasma Cutting 

Though this technology sounds quite futuristic, the truth is that it’s been around for more than 60 years. The plasma cutting machines of that era are primitive going by today’s standards. This is more so because the electrodes and nozzles of those days deteriorated rapidly and the quality of their cut was somewhat unpredictable and imprecise.

Modern plasma cutting has seen a remarkable improvement in enhancing the usability of these machines. These aspects include:


Modern plasma cutting is more efficient than that of the technology’s germinal phase. Today this technology relies on less input power to accomplish the same amount of work.

Power Options and Controls

Lower and higher output levels and better fine-tuning give manufacturers and users more control and boost the ability to use these cutters in a wider range of applications.


Unlike the older devices that would leave behind some rough edges and inconsistent quality of work, today’s machines are more precise and offer exact cuts and sharper edges.


Thanks to advances in technology, modern plasma cutting machines make use of automated qualities and computer programs to ensure more successful cuts.


Today’s plasma cutters are becoming smaller and easier to carry and use. However, do not be surprised to come across large machines that still exist for cutting thick metal. Incidentally, most manufacturers now rely almost exclusively on handheld units.

Selecting Plasma Cutting Machines – A Beginners Guide

There are numerous factors you should consider when buying this welding equipment.

The thickness of the material that you’ll be cutting frequently is one such factor. If you’ll be generally cutting thicker material, a higher amperage machine is the most ideal option for you.

Determine the optimal desired speed. How fast do you want to make the cuts? Check on what the manufacturer says about the cutting speeds for metals of different thicknesses.

Lower amperage plasma cutters are better suited for thinner materials. This category of plasma cutters provides better control and cleaner cuts.

Consider how the plasma cutter starts. Plasma cutters that have a pilot arc and utilize high frequency to conduct electricity can interfere with office equipment including computers.

If you’ll be operating in such an environment, it’s prudent to select a cutting machine that utilizes the lift arc method. This uses a DC negative electrode and a DC positive nozzle. In a nutshell, this type of plasma cutter will not damage your office equipment.

Essential welding safety gear is a crucial factor to consider when buying these machines. Remember, it’s the nozzle that protects you from the high voltage used to establish the arc. Any slight mistake can lead to a serious accident.

Ensure you get a machine that comes with a ‘nozzle-in-place’ safety sensor which makes sure you cannot start the machine without the nozzle.

We will be happy to hear your thoughts

Leave a reply

Welding Insider