How Do Plasma Cutters Work?

Grainger Editorial Staff

The sheer strength of metal has made it the go-to material for producing so much of what we all depend on, both in manufacturing and in our everyday lives. Its strength, however, can also double as a weakness because it isn't easy to mold, cut or manipulate. Plasma cutters are meant to help with this task.

What Is a Plasma Cutter?

A plasma cutter sends an electric arc through a gas while passing through a constricted opening. Using extreme heat, plasma cutters elevate the temperature of the gas and convert it to a fourth state of matter called plasma. In conjunction with a compatible plasma torch, this instrument can pass through metals like steel, aluminum, brass and copper with little or no resistance. This sharp welding process allows for cleaner, sliced lines and sturdier constructions.

Perfecting the Production Process

Plasma cutters are a necessity in the manufacturing industry, from construction companies and auto shops to locksmiths. As technology has progressed, so has this instrument’s design and capability. Plasma cutters and torches typically fall into two categories: handheld and machine.

Handheld cutters are versatile and often portable, making welding jobs more convenient. They deliver high-cutting amperage but are typically used in light-metal applications for trimming excess material.

Mechanized plasma cutters, on the other hand, are used for large-scale jobs. They include more features and are used in conjunction with cutting tables. These systems cannot be moved easily, as they require a larger power supply to work. Choosing between a mechanized or manual cutter depends on the size, shape and thickness of the material that needs to be cut.

CNC cutting tables include software that can be programmed to execute intricate designs.

The Oxy-Fuel Torch Option

Oxy-fuel cutting machines are also used in machining and manufacturing to cut through tough materials. These machines work using an oxygen/fuel gas flame to preheat steel to its ignition temperature. Then, a high-powered oxygen jet is directed at the metal creating a chemical reaction to form iron oxide, also known as slag. The jet then removes the slag from the cut.

Hand held cutting torches, also called oxy-fuel torches, are also used to cut through tough materials like metal and are more commonly used than cutting machines. Cutting torches are used to cut through thick steel and stainless steel and are work well for demolition tasks. notes that oxy-fuel might still be preferred in some cases. It doesn't require compressed air or an electrical source which makes these torches highly portable. Oxy-fuel torches also cut thicker steel pieces more easily than plasma. A typical handheld oxy-fuel torch can cut through thicknesses up to 12 inches. However, it can only cut steel and other ferrous metals because it relies on oxidation.

Plasma cutters, meanwhile, can slice through materials faster than oxy-fuel torches. They also do not use gas or open flames, making them potentially safer. Each type has its advantages for certain types of jobs.

Learn more about Grainger metalworking and machining resources and services.

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The information contained in this article is intended for general information purposes only and is based on information available as of the initial date of publication. No representation is made that the information or references are complete or remain current. This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. Readers with specific questions should refer to the applicable standards or consult with an attorney.

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