Plasma cutting is the most widely used cutting method in the metal processing industry. Next, we come to understand the working principle, the advantages, and disadvantages of plasma cutting.
What is plasma cutting?
Plasma cutting uses high-temperature, high-speed gas jets at the nozzle to ionize to form electrical conductors. When the current passes, the conductive gas forms a high-temperature plasma arc. The heat of the arc locally melts (and evaporates) the metal at the incision of the workpiece and uses the power of the high-speed plasma flow to remove the molten metal to form an incision. The slender and stable plasma arc formed by the annular airflow technology ensures that any conductive metal can be cut smoothly and economically.
What are the classifications of plasma cutting methods?
Plasma cutting is mainly divided into dry plasma cutting, semi-dry plasma cutting, and underwater plasma cutting.
What are the advantages of plasma cutting?
1. Compared with oxy-fuel cutting, plasma cutting has a wider cutting field. The plasma cutting method can cut conductive non-ferrous metals.
2. The plasma cutting method has a fast cutting speed and high efficiency, and the cutting speed can reach more than 10m/min.
3. The cutting accuracy of plasma cutting is higher than that of oxy-fuel cutting, and the precision of fine plasma cutting can reach the lower limit of laser cutting.
4. The use and maintenance cost of the plasma cutting method is low in the later stage, and only relevant consumables and wearing parts need to be purchased, but the matching plasma power supply needs to be purchased in the early stage.
5. The plasma cutting method has high cutting quality, smooth and flat slits, narrow cuts, and the heat-affected zone and deformation are smaller than flame cutting.
What are the disadvantages of plasma cutting?
1. In the plasma cutting method, when cutting thick plates, the cut is V-shaped.
2. In the plasma cutting method, if the metal thickness is less than 5mm, it will cause a relatively large amount of deformation during cutting. When cutting metal with a thickness of more than 30mm, a high-power plasma power supply is required, and the cost is relatively high.
3. The plasma cutting method produces noise during cutting, dust, harmful gas, and arc pollution, which will affect the working environment.
What are the advantages and disadvantages of underwater plasma cutting?
The working principle of the underwater plasma cutting machine is that the underwater plasma cutting can remove dust. There is a cutting platform with a water level that can be raised and lowered. When cutting starts, the air inlet valve opens the fan to inflate the water bed airbag, and the water level rises quickly. When the water just floods the steel plate, the pneumatic is closed. Valve, the water level stops, the smoke and arc generated during cutting are all absorbed by the water. When the cutting is over, the air outlet valve opens, and the airbag deflation water level drops for the operator to mark and unload. This kind of dust removal method is currently the best dust removal method.
Advantages of underwater plasma cutting
The crossbeam adopts a wide-body reinforced box structure with a beautiful appearance. The end frame adopts a low-center-of-gravity structure with symmetrical structure and good stability. All welding is stress-relieved to ensure the overall rigidity and good dynamic balance. The underwater plasma cutting method can minimize the impact of plasma cutting on the working environment.
Disadvantages of underwater plasma cutting
The underwater plasma cutting method must be equipped with an anti-collision device or an arc voltage automatic height adjustment device, and the cost is high. During underwater cutting, the water surface is easily turbid due to the impact of arc ignition and cutting gas. The naked eye cannot see the position of the cutting torch and the height of the cutting torch from the steel plate. During the cutting process, if the steel plate is deformed, The bulge will collide with the torch, causing the torch to break or damage. And there are fewer manufacturers capable of producing underwater plasma cutting machines. The underwater plasma cutting method is affected by water, and the cutting speed, cutting ability, and surface finish are reduced to different degrees compared with dry cutting. The power consumption when cutting steel plates of the same thickness is about 15% higher than that of dry cutting. The manufacturing cost of the water bed is relatively high.
