Views: 12 Author: Maichuang Laser Publish Time: 2021-09-07 Origin: MC
The nozzle is used to spray auxiliary gas to the cutting area. Generally, a coaxial (air flow and optical axis coaxial line) nozzle is used on a laser cutting machine. About it, the universe is big and it will affect the cutting quality if it is not done well.
1. The shape of the nozzle
There are many types of nozzles, including cylindrical, conical, and zooming types.
Second, the requirements of the nozzle hole
The size of the nozzle hole must allow the beam to pass smoothly and avoid the beam in the hole from contacting the nozzle wall. Obviously, the smaller the inner diameter of the nozzle, the more difficult it is to collimate the beam. In addition, the auxiliary air flow from the nozzle must be effectively coupled with the removal of molten products in the slit and the enhancement of the cutting action. The wall of the nozzle hole should be smooth. In order to ensure the smooth airflow, avoid turbulence and affect the quality of the incision.
3. The distance between the nozzle and the surface of the processed material
The coupling of nozzle airflow and workpiece slitting is an aerodynamic problem, and the discharge airflow pattern and the distance between nozzle and workpiece are both important variables. If the nozzle orifice is too close to the surface of the workpiece during processing of the laser cutting machine, a strong return pressure to the lens will be generated, which will affect the ability to disperse the material produced by the splash cutting; but the nozzle is too far away from the surface of the workpiece, which will also cause Unnecessary loss of kinetic energy. Generally, the distance between the workpiece and the nozzle is 1~2mm. The cutting of special-shaped workpieces mainly relies on automatic height adjustment devices, such as contact, return pressure and feedback devices such as changes in inductance and capacitance.
Fourth, the size of the nozzle
The size of the nozzle will affect the cutting quality such as the size of the thermal reaction zone and the width of the slit during the processing of the laser cutting machine. As the diameter of the nozzle increases, the heat-affected zone becomes narrower. The main reason is that the airflow from the nozzle has a strong cooling effect on the matrix material in the cutting zone. If the nozzle diameter is too large, the slit will be too wide. If the nozzle is too small, it will cause difficulty in alignment and induce the beam to be clipped by the small nozzle opening. Therefore, the commonly used nozzle diameter is 1~1.5mm.