The cutting head of the laser cutting machine is used in a very harsh environment, so in order to protect the internal optical path and core components, especially the expensive components such as collimator and focus lens, the cutting head must be equipped with upper and lower protective lenses. The dust and splashes generated on the surface of the workpiece during the cutting process will cause serious damage to the focus lens if they enter the cutting head, and the lower protective lens can block these dust and splashes.
The cleanliness of the protective lens directly affects the processing performance and quality of the laser cutting machine. If the lens is dirty, it will not only affect the cutting effect and efficiency, but also further cause the burning of the internal parts of the cutting head and the laser output head. Therefore, it is necessary to first use the protective lens with good material, high transmittance and low thermal expansion coefficient. When the lens is dirty during the processing, it needs to be cleaned or replaced.
There are special process requirements for the processing of laser cutting head protective lenses. There are different processing requirements from the selection of base materials, processing accuracy, surface defects, coating, stability, mechanical properties (specific gravity, brittleness, tensile strength, compressive strength, hardness), and material preparation in the processing process → scarring → sand hanging → grinding → coring → coating. The finished products can also be put on the market after strict quality inspection.
In order to reduce the cost, the low-quality laser cutting head protection mirror is made of ordinary base material, the coating process is not guaranteed, the light transmittance is poor, it is not heat resistant, it is easy to crack, and it can not bear the penetration of the laser, resulting in the lens hole explosion, and the broken lens powder particles will pollute the entire cutting head, thus causing damage to the core high-value components including the focus lens, sensor, etc., and the maintenance cost will be up to 20-50% of the price of the new cutting head, In addition, the terminal production and processing are delayed, resulting in greater economic losses.
