Precautions in pattern metal plate cutting
[phenomenon]
Patterned metal plates are generally made of carbon steel, stainless steel or aluminum alloy. If the raised part of the patterned metal plate is placed upward for cutting, the carbon steel will be more prone to melting loss.
[reason]
When the heat conduction speed is faster than the cutting speed, the heat will converge at the corner of the bulge, the position relationship between the material surface and the nozzle or the processing lens will also change at the bulge, and the auxiliary gas pressure or focus position conditions will deviate from the normal value.
[solution]
The methods for high-quality cutting of checkered steel plate include: (1) reducing the concave convex change of convex part; (2) Inhibit the concentration of heat energy to the convex part.
A. reduce the influence of concave convex part of protrusion
When placing the plate, place the convex surface as the processing back (bottom surface) and the surface without concave convex as the laser irradiation surface, so as to reduce the change degree of auxiliary gas pressure or focus position on the processing surface. When setting the processing conditions, the height of the convex part shall also be taken into account, and the cutting conditions of the maximum plate thickness t shall be set. If the processed object is a relatively large plate, the workload of turning up and down may be relatively large, but it is an effective method to reduce melting loss.
B. inhibit the concentration of heat energy to the convex part
When the convex concave surface has to be cut as the processing surface (surface), the cutting speed condition should be set to be greater than the heat conduction velocity (F = 2m / min). The focus position shall be set at the apex of the convex part, and the surface width of the slit of the convex part shall be as small as possible. These are the key to good processing quality. The injection amount of auxiliary gas also affects the amount of melting loss. The nozzle with small diameter shall be selected to minimize the consumption of auxiliary gas.
In addition, in this cutting, the profiling of the capacitive sensor at the front end of the nozzle that maintains a certain distance between the nozzle and the surface of the workpiece will be very difficult. In this case, the profiling needs to be carried out through the contact sensor, and the profiling needs to be limited above the convex part.