Generally speaking, the function of the focusing mirror of the laser cutting machine is to concentrate the beam. These focus points can be adjusted and are not fixed. Some focus automatically and others manually focus. But each lens has its own focal length, but most of the range of phase difference is not very large. After determining the focal length, you must first grasp the focal point, find the focal point on the lens, and then adjust the focal length according to the actual quality during processing. The focal length of the focusing lens of each laser cutting machine is different. The focal length of the focusing lens of the general small laser cutting machine is basically 50.8MM and 63.5MM, which is actually the distance between the focusing lens and the material. We can use a steel ruler to measure the height of the lower lens.
The thickness of carbon steel cut by a CNC laser cutting machine is mainly determined by the laser output power. Taking carbon steel as an example, a 1KW laser cutting machine can cut 9 thicknesses (that is, 9mm), and 1.5KW can cut 19 thicknesses; for stainless steel, a 2.5KW laser cutting machine can only cut 15 thicknesses. Thicker, you need to configure a high-power laser above 3kw.
However, for carbon steel plates within 10mm, a fiber laser cutting machine under 1000W can be used for cutting. This is because the cutting width of laser cutting is narrow, generally between 0.1 and 0.5mm; the cutting accuracy is very high, less than 0.05mm, and the error of the hole center distance is between 0.1 and 0.4mm, and the error of the outline size is also 0.1 to Between 0.5mm; the cutting section is smooth, and the cut roughness is less than 25μm. After the workpiece is cut, it does not need to be processed again and can be welded directly.
For carbon steel plates above 10mm and below 20mm, you can choose a CO2 laser cutting machine of about 2000W, because the steel plate of this thickness cannot be cut by the current domestic fiber laser cutting machine. However, compared to wire cutting, CNC plasma cutting and water cutting, CO2 laser cutting is much more efficient and cutting costs are much lower.