I believe that many customers who have purchased a metal laser cutting machine should be familiar with laser nozzles. The shape, diameter, and height of the nozzle (the distance between the nozzle exit and the surface of the workpiece), etc., will all affect the cutting effect. Let the editor come to popularize knowledge for everyone.
The influence of the nozzle in the metal laser cutting machine on the cutting effect
The coaxiality between the nozzle outlet hole and the laser beam is one of the important factors that affect the quality of its grid.
The thicker the workpiece, when the nozzle is deformed or there is slag, it will directly affect the coaxiality. Therefore, the nozzle should be stored carefully to avoid damage to avoid deformation and clean up in time. The shape and size of the nozzle are manufactured with high precision, and the correct method should be paid attention to when installing.
If the nozzle and the laser have different axis, it will affect the cutting quality.
Effect on the cutting section When the auxiliary gas is blown out from the nozzle, the gas distribution is uneven, the right blowing volume is small, and the left blowing volume is large, resulting in slag on one side of the incision and no slag on the other side. When cutting thin plates below 3mm, its impact is small, when cutting more than 3mm, the impact is more serious, sometimes even unable to cut through.
The impact on sharp corners.
When the workpiece has sharp corners or the angle is small, overmelting is easy to occur, and the thick plate workpiece with sharp corners may not be cut.
The impact on perforation.
The perforation is unstable, the time is not easy to control, it will cause overmelting to the thick plate, and the penetration conditions are not easy to control, and the thin plate is less affected.
Nozzle diameter has a critical influence on cutting quality and perforation quality.
If the nozzle diameter is too large, the molten material splashing around during cutting may pass through the nozzle hole and splash the lens. The larger the diameter, the higher the probability of staining the lens, the worse the protection of the focusing lens, and the shorter the lens life.
The size of the nozzle diameter also affects the cutting quality such as the size of the heat-affected zone and the width of the slit.
As the diameter of the nozzle increases, the heat-affected zone becomes narrower and the slit becomes wider. The commonly used nozzle diameter is 1-1.5mm.
Nozzle height refers to the distance between the lower end of the nozzle and the surface of the workpiece. The nozzle height setting range is 0.5-4.0mm, and the common interval during cutting is 0.7-1.2mm. Too low will cause the nozzle to easily collide and get the surface of the workpiece, and too high will reduce the solubility and pressure of the auxiliary gas, resulting in a decrease in cutting quality. The height of the nozzle during punching is slightly higher than that during cutting, and it is set at 3.5-4mm, which can effectively prevent splashes generated during punching from contaminating the focusing lens.