Different industrial tools exist to help people with their hobbies and work. Some of these tools cut through various kinds of materials, like the handy plasma cutter. Some of you might wonder, What is a plasma cutter? How does it work? At what temperature could you operate it? And what makes it such an impressive tool?
We’ve prepared this article to help you understand how a plasma cutter works.
First, let’s define what plasma is:
Remember that there are three states of matter on Earth, namely, solid, liquid, and gas. Matter changes from one state to another, especially when it gets a certain amount of energy, such as extreme temperatures.
Based on what we learned in school, an ice cube (solid) becomes water (liquid) when exposed to high temperatures and then turns into water vapor (gas) when you boil it.
But what happens next when you keep on heating the gas?
When you continuously heat the gas, it becomes fully ionized and turns into a strong electrical conductor—this new phase is called “plasma.”
What is a plasma cutter?
A plasma cutter utilizes an accelerated hot plasma jet in order to cut through any conductive material. Some of those materials include aluminum, copper, steel, and stainless steel. Most people use plasma cutters for industrial settings such as automotive repair, marine salvage, and different mechanical applications.
Also, there are a lot of gases that may be used in a plasma cutter. This includes oxygen, nitrogen, argon, or shop air.
What are the key parts of a plasma cutter?
Before discovering more about plasma cutters, let’s have a closer look into the primary components:
A plasma torch keeps the consumables aligned and also cools them down. These consumables play a crucial role in plasma cutting and come with parts required to generate the plasma arc:
- Nozzle (where the air is released)
- Swirl ring
- Inner retaining caps
- Outer retaining caps
Arc starting console (ASC)
Before using a plasma cutter, the AC voltage should generate a spark inside the plasma. It should be around 5,000 VAC produced at 2MHz by the ASC circuit.
Plasma cutters use both AC and DC voltage. The plasma power supply transforms the AC line into DC voltage that ranges from 200 to 400VDC. The DC voltage then regulates the current output.
How does a plasma cutter work?
One of the main things about a plasma cutter is that it cuts through any conductive material. The machine starts with an accelerated jet of plasma heated at a very high temperature which then goes through the material and cuts it. Before taking a deep dive, here’s a step-by-step procedure that answers “how does a plasma cutter work?”
The plasma cutter was invented during the World War II era, a necessity for manufacturing guns, aircraft, and automobiles. With the precision it offers, this piece of metal fabricating equipment is still being used today.
The hot plasma jet is produced by compressed gas, which may be oxygen, air, or other inert gases arising from a small high-speed forced torch nozzle directed at the workpiece.
The external power supply then generates power to the electrical arc and immediately ionizes it, forming the plasma jet. The accelerated jet of plasma provides a high level of heat that melts down the material. On the other hand, high-speed plasma and compressed gas blow the liquid metal to cut through the materials.
Now, there are two different torches for plasma cutters. The first one is handheld torches, and the other is computer-controlled torches. Both are very effective and helpful to your work and your craft.
For most handheld tools, the operation seems simple and straightforward. Turning it on means, you will use it to cut; nothing happens when it's turned off because there's no contact between the nozzle and the electrode.
When it’s turned off, the electrode-nozzle connection is safe. But when you pull the machine’s trigger, a surge of DC voltage will supply power to the nozzle and electrode. That’s where plasma gas comes in.
By the time the compressed gas creates an ample amount of pressure between the nozzle and electrode, they will separate. An electrical spark enters to impact and replace the gas into a hot plasma jet. Then, the DC flows from the electrode into the workpiece in place of the nozzle.
However, things are a little different when it comes to the precision plasma touch. A wire wrapping separates the electrode and the nozzle. The same wire generates an oscillating flow called a “vortex shedding” from the plasma gas. When you turn on the power, an open-circuit voltage of up to 400VDC is transmitted. Then the gas is pressed to the torch, and you’ll see a swirling wire that separates the nozzle and electrode from the plasma gas.
When the nozzle is connected to the power supply’s positive charge, it makes the electrode negative. The electrical spark from the arc starting console forms a current from the electrode to the nozzle, creating a pilot arc made of plasma. When you let the pilot arc touch the workpiece, the current changes to keep the electrode flowing INTO the workpiece and NOT the nozzle.
The power supply ramps up the DC to cut the chosen amperage from the start. Then, it gets the post-flow plasma gas to aim at the workpiece. Simultaneously, a shielding gas flows from the shield cap to collide with and reshape the plasma arc.
Now, you’re ready to make a super accurate and swift cut!
With such a powerful tool that cuts through any metal—more importantly, through electrically conductive materials, you’ll certainly want to know how plasma cutters work. It lets you cut through complicated templates, curved or angled metals, and even straight formations. Plus, it powers through some of the thickest materials! What can you not do with this tool?
Featuring incredible precision, speed, and affordability, the plasma cutter is quite handy in a number of applications. How does a plasma cutter work? We’ve shared the quickest way to help both hobbyists and professionals understand the power tool in this guide.