When it comes to metal fabrication and welding, a common debate arises around which cutting technology is better: plasma or oxy-fuel. While oxy-fuel cutters were once the norm, advances in plasma cutting tables have added a new contender to the arena. In fact, the superiority of plasma cutting technology can be so impressive that even those who once relied solely on oxy-fuel may find themselves quickly won over. The truth is that both cutting methods have their own unique applications and benefits.
In this article, we’ll discuss the nuances of each cutting technology to help you determine which option is best for your factory/shop.
Oxy-fuel cutters have long been a go-to option for onsite work due to their portability and lack of electricity requirements. However, as plasma cutting technology has advanced, some models are now also portable and gaining popularity on modern construction sites. One notable difference between the two cutting methods is that oxy-fuel torches require the metal to be preheated to ignition temperature before cutting, while plasma cutters do not.
Additionally, while both cutting technologies produce fumes, plasma cutting typically generates less smoke and fumes than oxy-fuel cutting. This could be an important consideration for companies concerned about air quality and the health and safety of workers.
Overall, while oxy-fuel cutters remain a popular choice for portable onsite work, plasma-cutting technology is becoming increasingly portable and cost-effective. Additionally, plasma cutting can offer advantages in terms of precision cutting, versatility, and air quality.
Plasma cutting boasts a diverse range of cutting capabilities, as it can slice through both ferrous and non-ferrous metals, including aluminum, stainless steel, and cast iron. In contrast, oxy-fuel cutters are limited to cutting ferrous metals and can’t handle cast iron.
If you’re dealing with thicker cuts of metal, oxy-fuel torches are the way to go. These systems can cut steel up to 20 inches thick, while plasma cutters max out at one inch. However, when it comes to thinner metals, plasma cutters are the more effective choice, outperforming oxy-fuel cutters in speed and accuracy. Plasma cutters also have faster grate-cutting capabilities, making them ideal for stacking metals.
But that’s not all—plasma cutters are also better suited to cutting shaped metals, such as angles, channels, and tubes. So, when it comes to cutting capabilities, the choice between plasma and oxy-fuel ultimately depends on the type of metal and thickness you’re working with.
Slag and Cutting Speed
When metal is detached during the cutting process, it can melt and remain on the edge of the thickness of the metal. This excess metal is called slag. Removing the slag after cutting is easier with plasma cutting compared to oxy-fuel cutting, where it is often difficult to detach from the sheet.
Cutting speed is another factor to consider when choosing between these two technologies. Plasma cutting is generally faster than oxy-fuel cutting, even up to ten times faster in thin thicknesses. Unlike oxy-fuel cutting, preheating is not required with plasma cutting. However, cutting speeds for both processes decrease as the thickness of the metal increases.
Cutting speed also affects the thermal zone, with slower speeds resulting in greater heat added to the metal, which can lead to deformities in thin sheets ranging from 5 mm to 1.5 inches. While sheets less than 6 mm can be cut with oxy-fuel, the finish and quality of the process are generally not suitable for production compared to plasma cutting.
Besides producing slag, both oxy-fuel and plasma cutting also generate metal fumes and dust, which can be harmful to human health and the environment. To minimize waste production and ensure safe working conditions, proper ventilation, and respiratory protection should be used.
One advantage of plasma cutting is that it produces a narrower kerf (the width of the cut), which means less material is wasted during the cutting process. Both cutting technologies have some waste production associated with them, but plasma cutting is generally considered to be a cleaner and more efficient process.
When it comes to deciding between oxy-fuel and plasma cutting, one of the most important factors to consider is the cost.
An oxy-fuel setup usually costs only a fraction of what a plasma-cutting system would cost upfront. This can make it a viable choice for beginner fabricators or those with a limited budget. But it’s worth noting that ongoing costs for an oxy-fuel system can add up quickly due to the need for regular fuel cylinders and oxygen refilling. Plus, there might be some additional cylinder handling charges.
In contrast, plasma cutters have lower ongoing costs as they only require electricity to run. This makes them a cost-effective option, especially for those who plan to use their cutting system frequently.
It’s also worth noting there’s not much of a difference between the electrodes and replacement tips on a plasma cutter and those on an oxy-fuel cutting outfit. So, while the initial investment for a plasma-cutting system may be higher, the ongoing costs can be more manageable.
In the end, a combination of both technologies is usually required to handle the diverse range of jobs in sheet metal manufacturing operations. At Squickmon’s, we offer a wide variety of CNC plasma cutting tables and burn tables for sale that can assist you in your projects.