In recent years, laser cutting has become increasingly prevalent in the industrial industry due to the rapid development of the economy. Apart from the traditional laser cutting machines, laser pipe cutting machines have also gained significant importance.
As engineering machinery, transportation, petrochemical, and agricultural machinery industries continue to evolve, more and more users have begun to recognize the significant role pipe parts will play in future economic construction.
However, the process of laser pipe cutting produces a considerable amount of dust, which can be detrimental to both the environment and personnel.
It can also severely impact the clamping accuracy, processing efficiency, and processing accuracy of the laser pipe cutting machine, emphasizing the importance of efficient dust removal for the laser pipe cutting machine.
A laser pipe cutting machine is mainly used for cutting various pipe fittings and profiles using laser technology. It is designed to clamp the fittings or profiles with chucks for precision cutting.
During pipe cutting, dust is generated from both ends of the pipe. Similarly, when cutting profiles, a large amount of dust is generated at the cutting head. To ensure cutting efficiency and control production costs, manufacturers of laser pipe cutting machines typically add suction and dedusting pipes to both ends of the pipe. The high-power suction fan or deduster continuously sucks out the cut dust, which improves the cutting dedusting effect.
There are many factors that affect the dedusting effect of a laser pipe cutting machine. This article analyzes the inherent characteristics of the pipe to be cut, the selection of chucks, and the selection of auxiliary gas based on practical experience.
Influence of the inherent characteristics of the pipe to be cut on the cutting dedusting effect
In general, cutting ordinary carbon steel pipes produces more dust than cutting stainless steel or other materials. This is due to the vulnerability of ordinary carbon steel to environmental impact, which causes it to rust and corrode quickly, resulting in a large amount of dust being generated during cutting.
Furthermore, laser pipe cutting machines work by illuminating the cutting light spot on the surface of the pipe to be cut, which raises its surface temperature to the melting or boiling point in a short period of time. This process creates small holes at the cutting end of the pipe.
The auxiliary gas used during the cutting process blows away the molten material around the small hole, leading to the formation of dust.
Most ordinary carbon steels contain a high level of carbon, and when they are cut, oxygen is commonly used as an auxiliary gas. However, this gas easily oxidizes on the cutting surface, improving cutting efficiency but also leading to an increase in dust.
To ensure efficient and accurate cutting of thick pipes, high-power laser generators are often utilized, which can quickly produce more dust during the cutting process.
Therefore, when cutting pipes, it is advisable to select stainless steel or other materials whenever possible. If carbon steel pipes must be used to reduce costs, a rust removal treatment can be carried out on the surface of the pipes to minimize the corrosion caused by oil and water stains.
Influence of chuck selection on cutting dedusting effect
Manufacturers of laser pipe cutting machines typically choose chuck combinations that are suitable for their products. The dust prevention effect of chucks is improving, particularly for the chuck at the feeding end.
However, the chuck at the feeding end, despite playing the role of feeding, is more prone to accumulating dust due to the hollowing of the pipes.
There are two primary methods for dust-proofing feed chucks on the market:
One approach is to improve the sealing accuracy of the chuck itself, particularly the sealing accuracy of the jaw slider of the chuck at the feeding end, to maintain good sealing even after clamping the jaw multiple times during multiple cutting.
The second approach is to place a dedusting hose at the tail of the feeding chuck, connect it to the dedusting fan, and absorb the dust at the feeding chuck through the suction of the dedusting fan when it is working.
The clamping chuck at the cutting end, located near the cutting head, produces a considerable amount of dust, whether cutting normal pipe parts or special-shaped parts such as profiles, which can impact its clamping accuracy due to dust accumulation.
Therefore, a suction outlet device is installed near the clamping chuck, and a dedusting hose is also placed behind it, connected to the dedusting fan, so that dust can be extracted during operation, as illustrated in Figure 1.
Fig. 1 Dust removal pipe near cutting head
Influence of auxiliary gas on cutting dedusting effect
The laser pipe cutting machine focuses the laser beam through a lens to form a light spot on the surface of the pipe to be cut. This causes a rapid increase in temperature, melting or boiling the pipe at that point.
During the cutting process, the pipe’s surface can reflect the laser, so an auxiliary gas is injected to enhance the laser’s absorption. Fine dust particles accumulate during the cutting process, both visible and invisible to the naked eye.
Over time, these particles accumulate in the optical path components, damaging the cutting equipment and increasing the cost of laser cutting. Using auxiliary gas can blow away the dust, preventing pollution of the equipment.
Auxiliary gases, such as oxygen, compressed air, and nitrogen, are used during cutting. When oxygen is used, oxidation reactions occur on the surface of the pipe, improving the cutting efficiency. However, it generates a significant amount of dust when cutting ordinary carbon steel pipes.
For parts with low accuracy requirements, compressed air is used as an auxiliary gas to control production costs and reduce the production of dust to some extent. Inert gases like nitrogen produce a finer and smoother cut surface, less dust, and a smaller laser cut kerf. It’s more conducive to cutting special-shaped pipes like H-shaped steel, channel steel, angle steel, etc. However, it increases the production cost.