A brief description of the single or double layer of the nozzle
Single-layer laser nozzle is used for melting cutting, that is, nitrogen as auxiliary gas, cutting stainless steel and aluminum plate with single-layer laser nozzle.
Double-layer laser nozzles are generally used for oxidation cutting, that is, using oxygen as an auxiliary gas to cut carbon steel with double-layer laser nozzles.
Laser nozzle - Laser cutting
The problem of nozzle aperture selection
The nozzles with different aperture holes are mainly used for cutting plates with different thicknesses, and the thin plates use the ones with smaller spray holes, and the thick plates use the ones with larger spray holes. The nozzle aperture is: 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, etc., and the most used is: 1.0, 1.2, 1.5, 2.0, 2.5, 3.0, which is the most commonly used 1.0, 1.5, 2.0. The aperture of the nozzle controls the flow of gas and the shape of the gas field, which is very important for the cutting quality. Generally, when the laser cutting machine is used to cut the thin plate below 3mm, it is recommended to choose a nozzle with a diameter of 1mm, and a nozzle with a diameter of 1.5mm is recommended for the thickness of more than 3mm. When cutting more than 10mm of metal sheet, generally choose a nozzle with a diameter of 2mm or above.
Nozzle quality from those aspects
Look at the material, a good nozzle, the material must have high conductivity and good thermal conductivity. Generally, the nozzle made of copper will be better than that made of brass, which can ensure a good capacitance signal.
Look at the processing accuracy: a good laser head nozzle, its concentricity to reach 0.03mm, and the size of the nozzle below 1.0mm, the concentricity is to reach 0.02mm. The high-precision concentricity nozzle can not only reduce the early debugging of the processing process, but also effectively avoid the high-energy laser hitting the inner wall of the laser head, so as to avoid damage to the laser head.
When the center of the nozzle is not coaxial with the center of the laser, the impact on the cutting quality is:
1. Affect the cutting section, when the cutting gas is emitted, resulting in uneven gas volume, so that the cutting section is more prone to melt on one side, the other side is not the phenomenon, the cutting of 3mm below the sheet, its impact is less, in the cutting of 3mm above the sheet, its impact is more serious, sometimes can not be cut.
2. Affect the quality of sharp corners, when cutting the workpiece with sharp corners or small angles, it is easy to produce local over-melting phenomenon, and when cutting thick plates, it may not be able to cut.
3. Affect the perforation, the instability in the perforation, the time is not easy to control, the penetration of the thick plate will cause over-melting, and the penetration conditions are not easy to master, and the impact on the perforation of the thin plate is small.
4. Look at the surface finish and anti-oxidation treatment: smooth surface and good anti-oxidation treatment can effectively reduce the adhesion of melt in the cutting process and extend the service life of the nozzle.
