The best way to cut materials made from electrically conductive metal is by using an accelerated jet of hot plasma in metalwork. This cutting metal process is the most effective if you are looking for a way to cut thick metal sheets. Plasma cutting offers unlimited possibilities, whether you are into artwork using metal or designing new finished parts. It is a reliable metal cutting technique for cutting metals such as stainless steel or aluminum.
If you are curious to know how this relatively new technology of cutting metal works, read on for more information.
Plasma cutting was first introduced in the metalwork industry to cut metals that couldn’t be fired. Such metals include stainless steel, copper, and aluminum. Investing in the tight plasma /protective gas combination reduces the cost of the metal cutting process.
How Does Plasma Cutting Work?
Before we get an answer to this question, let’s first define plasma cutting. The process uses an accelerated jet of hot plasma to cut electrically conductive materials. In most cases, the type of metal materials best cut with a plasma torch include metals that can conduct electricity, including copper, brass, aluminum, and stainless steel. Industries dependent on plasma cutting include the automotive sector, manufacturing, scrapping, salvage, and industrial construction. Most industries prefer using plasma cutting because it cuts metals at the very first-rate and maximum precision.
The basic process in plasma cutting and welding involves creating an electrical channel made from electrically ionized gas heated at very high temperatures. This is known as plasma. The plasma-cutter completes the electric circuit that passes through the cut material through an earth terminal. For this process to occur, a gas such as oxygen, inert gas, or hair is compressed based on the material that needs to be cut. The compressed gas is then blown at great speeds through a focused nozzle.
An arc is formed between the cut material and an electrode near the gas nozzle within the gas. An electronically conductive channel is formed when the electric arc ionizes a portion of the gas. Enough is to cut through the workpiece is generated when the current from the cutting torch of the plasma cutter flows through this plasma. The molten metal is blown away by the compressed gas that blows at high speeds dividing the metal material that is being cut.
Both thick and thin metal materials are cut effectively with plasma cutting. When using hand torches, plasma cutters can cut thick metals of up to 33 mm thick. For thicker metals of about 150 mm, powerful computerized torches are used. Plasma cutters are quite useful for welding and cutting angular or curved shapes since they produce very hot localized “cones” when cutting metal.
Benefits of Plasma Cutting
- Can be operated using one or more burners based on the series
- The user can cut any kind of metal provided it can conduct electricity
- Plasma cutting allows the user to cut medium and large high-alloy steel and aluminum materials
- The system produces great performance when working with medium and small mild steel
- Is uses a low heat input to cut high-strength structural steel
- Compared to oxy-fuel, plasma has high cutting speeds of up to 10 times higher
- Plasma cutting is also perfect for cutting high-quality blanks for medium and thick sheet metals
- You can operate the plasma cutting torch by automation
- Underwater, plasma cutting doesn’t make much noise and operates on very low heat exposure
Plasma Cutting and Welding Using Water Injection
In many industrial processes that lead to high temperatures, water is used as a coolant. Water is also used in plasma cutting to prevent machines from overheating, which leads to damages. Using an injector, water is injected into the plasma arc of the plasma cutter. When nitrogen is used as plasma gas, the plasma arc is normally created. This is common with many of the plasma cutters. High constriction is brought by the water injected into the plasma arc.
The temperature rises significantly to 30,000°C and above in this process. Besides improving the quality of the cut in plasma cutting, the cutting speed is also improved. This lowers the risk of double curvature and reduction of erosion in their nozzle.
Increased Constriction Effect in Plasma Cutting
For better containment of the plasma column and a more stable necking arc, swirl gas is used in the plasma cutting. The centrifugal force moves the maximum pressure point to the edge of the plenum and the minimum pressure point much closer to the axis when the number of inlet gas vortices increases. The number of swirls will increase based on the difference between the maximum and minimum pressure. High current density and ohm heating near the axis result from the large pressure difference in the radial direction that narrows the arc.
The next cutting edge thermal cutting tech that came after plasma cutting is laser cutting. In this metal cutting system, the laser beam is generated in the resonator cavity. The purity and the correct composition are decisive since the consumption of the resonator gas is low. The devices are protected by special resonator gases that come from the cylinder into the resonator cavity. This optimizes metal cutting, leading to greater performance.
The beam path system guides the laser beam from the resonator to the cutting head when cutting or welding metal. For high-performance systems, the system should be solvent, vapor, and particles. The two main gases used in laser cutting are nitrogen and oxygen. When cutting or welding metals made from low-alloy steel and unalloyed steel, oxygen is used. The process is the same as in oxy-fuel cutting.
The introduction of plasma cutting in the metalwork industry has made it easier and faster to weld or cut metal. The process also produces precise and polished finishing when cutting metal. However, you need to invest in the right plasma cutter and coolant if you want to get the best of this metal cutting technology.