There have three kinds of focus of laser cutting machine:
1. Cutting focus on the workpiece In this way we also become negative focal length, because the cutting point is not located on the surface of the cutting material or inside the cutting material, but is positioned above the cutting material. This method is mainly used with materials with high cutting thickness. In this way, the focus is on the cutting material above, mainly because the thick plate needs a large cut, otherwise the nozzle transport oxygen is very easy to appear caused by insufficient resulting in lower cutting temperature.
But one drawback of this approach is that the cutting surface is relatively rough and less practical for high-precision cutting.
2. Cutting focus inside the workpiece this way also becomes the positive focal length. When you need to cut the workpiece for stainless steel or aluminum steel plate often use the cutting point inside the workpiece mode. However, one drawback of this approach is that, due to the focus principle of cutting the surface, the cut is relatively larger than the cutting point on the surface of the workpiece, while this mode requires a large cutting airflow, the temperature to be sufficient, cutting perforation time a little longer.
So when you choose the material of the workpiece is mainly stainless steel or aluminum lamp hardness of the material when selected.
3. Cutting focus on the surface of the workpiece This method also becomes 0 focal length, generally commonly used in spc,sph,ss41 and other workpiece cutting, the use of the focus of the cutting machine is close to the surface of the workpiece, this mode of the workpiece up and down the surface smoothness is not the same, in general close to the focus of the cutting surface is relatively smooth, and away from the cutting focus of the lower surface appears rough.
This model should be based on the process requirements of the upper and lower surfaces in the actual application. To sum up, we use laser cutting machine to process different workpieces need to use different focus mode, can give full play to the performance advantages of laser cutting machine.