Ⅰ. The relationship between nozzle and cutting quality: When the nozzle center and the laser center are not on the same axis, the effect on cutting quality:
1) Affect the cutting section. When the cutting gas is sprayed out, it will cause uneven air volume, which makes it easier for the cutting section to have melting stains on one side and not on the other side. It has little effect on cutting thin plates below 3mm. When cutting a sheet of more than 3mm, its impact is more serious, sometimes making it impossible to cut.
2) Influencing the quality of sharp corners, when cutting workpieces with sharp corners or small angles, it is easy to produce local overmelting. When cutting thick plates, it may not be possible to cut.
3) Affect the perforation, instability during perforation, time is not easy to control, the penetration of thick plates will cause overmelting, and the penetration conditions are not easy to grasp, and the impact on thin plates is small.
Ⅱ. The choice of nozzle aperture: There are several kinds of nozzle diameters: φ1.0mm, φ1.5mm, φ2.0mm, φ2.5mm, φ3.0mm, etc. At present, two kinds of nozzle apertures are φ1.5mm and φ2mm. The difference between the two is:
1) Thin plates below 3mm: Use φ1.5mm, the cutting surface will be thin; use φ2mm, the cutting surface will be thicker, and the corners will be easily melted.
2) Thick plates above 3mm: Due to the higher cutting power, the relative heat dissipation time is longer, and the relative cutting time also increases. With φ1.5mm, the gas diffusion area is small, so it is not stable when used, but it is basically usable. With φ2mm, the gas diffusion area is large and the gas flow rate is slow, so the cutting is more stable.
3) The hole diameter of φ2.5mm can only be used for cutting thick plates over 10mm.
In summary, the size of the nozzle aperture has a serious impact on cutting quality and perforation quality. At present, laser cutting mostly uses nozzles with φ1.5mm and φ2mm apertures.
Reminder: When the nozzle is deformed or there are melting stains on the nozzle, its impact on the cutting quality is the same as described above. Therefore, the nozzle should be placed carefully and not scratched to avoid deformation; the melting stain on the nozzle should be timely Clean up. The quality of the nozzle has high precision requirements during manufacturing, and the correct method is required during installation. If various conditions are to be changed during cutting due to the poor quality of the nozzle, the nozzle should be replaced in time.