Views:991 Author:Site Editor Publish Time: 2020-02-21 Origin:Site
In the laser cutting machine, it is necessary to know and deal with several kinds of core technologies for the parts with high precision or large thickness. Focusing position adjustment is only the first in the table. The first advantage of laser processing is the high power density of the light, so the focus light point is as small as possible, which is convenient to create a narrow slit. Because the smaller the focal depth of the focusing lens is, the smaller the diameter of the focus point is. For high-quality laser cutting, the reasonable relative aperture is also related to the lens diameter and the cutting material. Therefore, it is critical that the manipulation focus depends on the part where the material surface is cut off.
Because the load of particle beam illumination has a great influence on the laser cutting rate, the selection of lens focal length is a key problem. The size of the light spot after the particle beam auto focusing is positively related to the focal length of the lens. The size of the light spot after the light is focused by the short focal length lens is not large, and the lighting load at the focus is very high, which is very beneficial to the material laser cutting. However, its defect is that the relative aperture is very short, and the adjustment capacity is small, which is generally more suitable for the high-speed laser cutting thin material. Because the fixed focal length lens has a wide focal depth, if it has enough power density, it is more suitable for laser cutting thick workpiece.
After the clear application of several focal length lenses, the focus and the position of the steel surface layer are very important to ensure the laser cutting quality. In view of the high power density of the focusing part, in most cases, the focusing part is just on the surface of the steel piece or slightly below the surface during laser cutting. In the whole laser cutting process, the key premise to obtain the balanced laser cutting quality is to ensure that the focus and the steel parts depend on the constant position. Occasionally, the lens will encounter heat due to improper cooling, which will cause the focal length change. Therefore, the focal position must be adjusted immediately.
When the focus is in the suitable position, the slit is small and high efficiency, and the laser cutting rate can get good laser cutting results. In most applications, the light focus is adjusted to just under the nozzle. The distance between nozzle and steel surface is usually 1.6mm.
In the process of particle beam application, problems such as autofocus are often encountered. There are several simple operations to determine the focus position:
(1) Copy method: make the laser cutting head transport work from top to bottom, and carry out particle beam printing on the plastic plate. The smaller the printing diameter is the focus.
(2) Slant column method: use the plastic plate placed on the side with the same angle of view as the vertical axis to drive it to find the smaller point of the parallel beam to focus.
(3) Blue flame method: remove the nozzle, blow air, and beat the pulse light on the stainless steel plate, so that the laser cutting head moves from top to bottom, until the blue flame is focused at a large place. leapion
The data are for reference only