How to adjust the focus of laser cutting machine？

We all know that the fiber laser cutting machine has many advantages such as high cutting accuracy and smooth cutting surface. These advantages are actually closely related to the focus control of the laser cutting machine. According to the different materials and requirements we process, the cutting focus of the laser cutting machine should be adjusted. This is what we call focusing. With the rapid development of laser cutting machine technology, our focus control method has been gradually updated from the early manual focusing to the automatic focusing method. So how do we adjust the focus of the laser cutting machine? Let us take a look together below.

The focus position of the fiber laser metal cutting machine can be divided into the following three aspects:

The cutting focus of the laser cutting machine is on the surface of the workpiece

This focusing mode is also called zero focal length. This focusing mode generally needs to be determined according to the actual situation, the processing requirements of the upper and lower surfaces of the material. Generally, the cutting surface close to the focal point is relatively smooth, and the lower surface away from the focal point of the cutting machine appears rougher.

The cutting focus of the laser cutting machine is on the top of the workpiece

The cutting focus is located above the cutting material. This focusing mode is also called negative focus. This focusing mode is mainly used to cut materials with high thickness. The reason why the cutting focus is positioned above the cutting material is mainly because the thick plate needs a large cutting width, otherwise the oxygen delivered by the nozzle is very likely to be insufficient and cause the cutting temperature to drop. But one disadvantage of this method is that the cutting surface is rough and not suitable for high-precision cutting.

The cutting focus of the laser cutting machine is inside the workpiece

This focusing mode is also called positive focus. In this mode, since the focus is far away from the cutting surface of the cutting material, the cutting width is relatively larger than the cutting point on the surface of the workpiece. At the same time, the cutting airflow is required, the temperature is sufficient, and the cutting and piercing time is slightly longer; therefore, the workpiece material is selected as stainless steel or aluminum It is used for materials with high hardness.