With the change of industrial production demand, laser cutting, as an advanced processing method, has become more and more accepted by the sheet metal producers. Laser cutting machine is regarded as an important means to promote the upgrading of traditional industry, but it still faces a huge bottleneck in the lack of application and the lag of the core technology.
Especially in the process of metal plate cutting, the cutting speed will decrease obviously, the repeatability of the incision is not good, and it can not compete with the traditional technology. If the laser cutting machine can overcome the difficulties in the process of thick plate cutting, there is no doubt that there will be a greater market prospect.
The problem of perforation of thick carbon steel plate
In the thick plate processing, perforation time accounts for a large proportion. Laser manufacturers have developed rapid perforation technology, and more representative is high-energy perforation. The advantage of this method is fast speed.
But the defect is that the huge energy injected in the perforation makes the plate temperature rise and affect the next whole cutting process, and it affects the small shape processing. When a small power pulse is used for perforation, the time is very long (12 seconds), which leads to a decrease in cutting efficiency and an increase in unit cost.
Quality problem of cutting surface
Figure 1. and figure 2. show the plate processing often meet the cutting section, this cutting not only product quality has been questioned, accompanied by burning and slag serious, that does not embody the laser machine price is different from other means of cutting value.
Figure 1. carbon steel cutting surface Figure
2. stainless steel cutting surface
The problem of the stability of the whole plate machining
In the whole plate processing of domestic steel, there is often a phenomenon of poor processing in local area. This phenomenon is sometimes very random, even when the machine is in good condition, it will greatly affect the whole work process in order to deal with local fault products.
[solutions to the above problems]
Just as its name implies, a peak value pulsed laser with small duty cycle is added, which is supplemented by fuel injection on the surface of the material to remove the attachment on the edge of the hole, and control the reasonable frequency of the pulse and the perforation of the cooling side.
Its characteristic is relatively deep hole, though time is a little longer (3 seconds), but its perforated hole is small (about 4mm), and there is no attachments on the edge of the hole and the inlet heat is low, which is convenient for the next normal cutting process. Compared with the ordinary perforation, the efficiency is increased by 4 times.
Bright face cutting
For carbon steel, the important factor to improve the cutting section is to control the heat of the plate and to ensure the full combustion of the laser beam. For stainless steel, the improvement of the cutting section is the improvement of the beam (improving the focal depth) and the effective utilization of the auxiliary gas. The technology of bright surface cutting is the result of improving the vibration and nozzle. The laser cutting machine of Hua SuperCut has bright surface cutting technology, and the finished products have more smooth section, higher accuracy and nearly perfect perpendicularity.
A scheme to guarantee the stability of processing
At present, in order to improve the running speed of the processing machine, the structure of the flying optical path is commonly used in laser cutting machine, that is, the movement of the material pallet not moving and the processing head moving in the whole Machinable area.
In order to compensate for the change of the relative position between the machining head and the light source, manufacturers are also trying to ensure the consistency of the spot in the processing area. The curvature variable refracting mirror is generally chosen.
Although this method is simple in structure, it will change the depth of focus, so that it will appear to be incapable of cutting heavy plate when it is highly sensitive to depth of focus. The long path way (between the source and the processing range of processing head light propagation path length) can avoid the depth of focus, so that the spot and focal depth are consistent. In addition to the attention of heat entry, the heat of the plate accumulation is controlled, and the stability problem is solved.
With the innovation of laser technology, the power of laser used in industrial production will also continue to grow. The future laser cutting machine will break through the existing cutting thickness limit step by step, and bring more surprises for industrial production.