What Is a Plasma Cutting Service?
A plasma cutting service is a method of melting and cutting metal by generating a plasma discharge between the metal of the workpiece and a tungsten electrode and then using a high-heat plasma stream to melt and cut the metal.
The surface temperature of the workpiece sprayed with a plasma discharge, or plasma jet, can reach 20,000°C, making it possible to cut any type of metal. Since the area around the plasma jet also becomes hot, it is common to cool the nozzle with cooling water.
Uses of Plasma Cutting Services
Plasma cutting service is mainly used for fusing stainless steel and aluminum alloys, which are difficult to fuse with gas, and is also used for high-speed cutting of mild steel. In principle, it can cut almost all metals and some non-metallic materials. In practice, however, it is widely used for mild steel plates ranging from thin sheets to 30 mm.
Among the most common uses are steel cutting in the construction industry, in the manufacture of special vehicles such as trucks, forklifts, and hydraulic excavators, in plant facilities such as power plants and port cranes, and in railroads, bridges, and ships.
Principle of Plasma Cutting Services
The higher the temperature of a substance, the more it changes state from solid to liquid and from liquid to gas. As the temperature of a gas increases further, the atoms of the gas separate into free electrons and ions, becoming an ionized gas. The electrons are then freed from their atomic orbits and change into plasma, which is called the fourth state of matter.
Plasma discharge is generated by a plasma arc discharge between the workpiece and a tungsten carbide electrode. The arc discharge causes the workpiece to melt at high temperature.
To further increase the density of the plasma arc, the arc is restrained and cooled by water-cooling nozzles. The plasma arc is then constricted so that the energy is no longer spread around and can be concentrated on a single point.
There are various methods of plasma cutting service, depending on the type of gas that envelops the plasma discharge emitted from the electrode.
1. Air Plasma Cutting Service
This cutting service uses air as the plasma jet. This is the latest plasma cutting service, and many compact devices have been developed. Small plasma cutting services for personal DIY use are available.
2. Oxygen-Plasma Cutting Service
This cutting service uses oxygen as a plasma jet. Since plasma cutting service uses plasma discharge and the heat of combustion of oxygen, it is possible to cut with very high energy. It is used for steel cutting by high-speed automatic cutting equipment, especially for cutting steel materials used in bridges and shipbuilding.
3. Hydrogen, Argon, and Plasma Cutting Service
This cutting method uses a mixture of hydrogen, argon, and nitrogen gases. The metal surface becomes beautiful with metallic luster because of the reduction effect of hydrogen. This method is mainly used for cutting nonferrous metals.
4. Nitrogen-Plasma Cutting Service
This is the oldest cutting method that uses nitrogen as a plasma cutting service. Due to the generation of nitrogen oxides caused by the gas used, this method has been used less frequently in recent years and has been replaced by oxygen-plasma cutting.
Other Information on Plasma Cutting Services
1. Advantages of Plasma Cutting Services
Processing of a Wide Variety of Materials Is Possible
Plasma cutting service can be performed on almost any material that can be energized. It is most commonly used for cutting mild steel sheets from thin sheets to 30 mm.
Curved Lines Can Be Cut
Plasma cutting service is capable of cutting not only straight lines but also curves, and can be used for complex and diverse product shapes.
Capable of Cutting Stainless Steel and Aluminum Alloys
Gas cutting is a method of cutting by oxidizing metals, and stainless steel and aluminum alloys are difficult to cut because they do not oxidize easily. Plasma cutting service enables easy cutting.
High Cutting Speed
Since high-temperature plasma is used as the heat source, the cutting speed is faster than that of gas or laser cutting. In addition, deformation of the cutting surface is reduced and the effects of melting are minimized.
Low Running Cost
Flammable gas is not required as in gas cutting, and a 200 V power supply and air compressor are all that is needed. Tungsten carbide used for electric discharge is non-consumable.
2. Disadvantages of Plasma Cutting Services
Requires a 200 v Power Supply
It is not suitable for outdoor locations where there is no 200 V power supply nearby or where only 100 V power is distributed.
Slag Treatment Is Required
In plasma cutting service, it is necessary to dispose of the slag that comes out of the molten part. If slag remains in the equipment, it will cause errors in the next operation and greatly affect product quality.