Do not choose inferior protective lenses for laser cutting heads, as the consequences are very serious!

The cutting head of a laser cutting machine is used in a very harsh environment, so in order to protect the internal optical path and core components, especially expensive components such as collimation and focusing lenses, upper and lower protective lenses must be installed on the cutting head. During the cutting process, dust and splashes generated on the surface of the workpiece will cause serious damage to the focusing 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 not only affects the cutting effect and efficiency, but also further causes the internal components of the cutting head and the laser output head to burn. Therefore, it is necessary to first use protective lenses with good materials, 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 protective lenses, including the selection of substrate materials, processing accuracy, surface defects, coating, stability, mechanical properties (specific gravity, brittleness, tensile strength, compressive strength, hardness), and the preparation of materials in the processing process ->raw folding ->sand hanging ->grinding ->coring ->coating. The produced products also undergo strict quality inspection before being launched on the market.

In order to reduce costs, low-quality protective lenses are made of ordinary substrate materials, which are not guaranteed by the coating process. They have poor light transmittance, are not heat-resistant, and are prone to breakage, making them unable to withstand the penetration force of laser light. This can cause lens holes to burst, and the powder particles that break the lens can contaminate the entire cutting head, causing damage to core high-value components such as focusing lenses and sensors. Maintenance costs can reach up to 20-50% of the price of the new cutting head, and delaying terminal production and processing, Causing greater economic losses.

Therefore, we hope that our customers can learn from this and purchase laser accessories from legitimate channels from manufacturers to avoid causing losses!The following are the adverse effects that poor quality protective lenses can easily cause

1- Thermal lens effect causing focus drift of the cutting head

Poor quality of protective lenses will increase the laser absorption rate. After continuous exposure for a long time, the temperature will rise and cause thermal deformation, which in turn causes the thermal lens effect to cause the focus of the cutting head to drift. The higher the power and the processing of high reflective materials, the faster the thermal expansion of optical components, and the more prominent the thermal lens.

(1) When cutting stainless steel, the focus drift of the thermal lens effect can cause inconsistent cutting section effects, increasing slag deposition, and even continuous cutting problems.

(2) When cutting carbon steel, the thermal lens effect can cause more and more slag at the bottom, resulting in continuous cutting problems.

2- Protective mirror burn point/burn through

Poor quality protective lenses have poor ability to block dust and splashes during processing, making them prone to burning points; For the ultra-high power processing head with ten thousand watts, protective lenses need to be carefully selected. Poor quality protective lenses under the action of ten thousand watts of laser can directly cause lens burnout in severe cases

3- Focusing mirror burning point

After the protective mirror burns through, if not detected in a timely manner, it continues to emit light for processing, causing particle smoke and dust to rise and contaminate the installation components, sealing rings, and the lower surface of the focusing mirror, resulting in burning points on the surface of the focusing mirror. It is necessary to thoroughly clean and replace the entire installation component and focusing mirror module.

4- Laser output head burnt out

For a 10000 watt laser device, once the protective mirror is burned through, it is very easy to instantly damage the internal collimation and focusing mirror module of the cutting head under the action of the ultra-high power of the 10000 watt. In the most severe case, when the internal optical components of the cutting head are damaged, an abnormal optical path will occur, causing the window of the laser fiber output head to overheat abnormally, ultimately burning out the QBH or LOE crystal. The entire laser output head needs to be replaced.

The use of inferior protective lenses not only affects the service life of the cutting head and causes various accidents, but also affects the processing progress and quality of the factory, thereby increasing processing costs and reducing factory efficiency. Here, we remind users that purchasing protective lenses must be done through legitimate channels and manufacturers. Do not let small gains outweigh big losses!