Maintenance of Laser Cutting Machine: 7 Useful Tips

Proper maintenance of a laser cutting machine is crucial to ensure its longevity, reliability, and optimal performance. Regular maintenance helps prevent issues, extends the lifespan of components, and ensures the safety of operators. Here are essential maintenance practices for a laser cutting machine:

How to Maintain Laser Cutting Machine

1. Daily inspection and maintenance of laser cutting machine

Before starting the machine each day, carefully check the working gas and cutting gas pressure of the laser. If the gas pressure is inadequate, it must be replaced promptly.

Check the X-axis zero point, Y-axis zero point, Z-axis zero point, laser readiness status, and other buttons for damage (verify the indicator light).

Verify that the mounting screws for the X-axis, Y-axis, and Z-axis zero points, limit switch, and mounting blocks are tightened and that the limit switches for each axis are responsive.

Ensure that the circulating water level in the chiller is adequate. If the water level is insufficient, add water promptly.

Check the external optical path’s circulating waterway for leaks, and promptly address any leaks; otherwise, the optical lens’s lifespan may be affected.

After each day of cutting, inspect the focus lens for damage.

Inspect the external light path’s telescopic skin cavity for burns or damage.

After completing daily work, promptly clean up the cutting waste, clear the work area, and keep it tidy. Also, ensure that all equipment parts are clean and free of dirt, and avoid placing debris on any equipment part.

After daily work is done, open the air compressor’s drain valve at the bottom of the air tank to drain the water. Close the drain valve once the waste water has drained.

After completing daily work, follow the shutdown procedure, and turn off the main power supply of the entire machine.

2. Weekly and irregular maintenance of the machine

It is essential to regularly clean the debris from the air outlet to ensure proper ventilation.

Check the filters in the gas path regularly to promptly remove any water and debris.

Ensure that the screws of the travel switch bracket and the bumper bracket are not loose by checking them regularly.

To facilitate the heat dissipation of internal electrical components, clean the dust from the filter screen of the electric control cabinet ventilation fan in a timely manner.

Cleaning the protective skin cavity of the guide rail on time is necessary to prevent damage to the guide rail, thereby extending its service life.

After installing the machine tool and using it for a period, it is vital to readjust the level of the machine tool to ensure its cutting accuracy.

Check the lubrication filling of the X, Y, Z axis guides, and lead screws every other week to keep the moving parts lubricated. This can extend the service life of X, Y, Z axis guides and their lead screws.

Depending on the environment of the workshop, it is important to irregularly (at least once a month) check the pollution on the surface of the reflector and focusing lens and clean the optical lens in time to ensure its service life.

3. Maintenance of external optical path optical lens

Avoid touching the surface of the optical lens (reflector, focusing lens, etc.) directly with your hands, as this can easily cause scratches on the mirror. If there are oil stains or dust on the mirror surface, clean it promptly to avoid affecting the lens’ performance.

Under no circumstances should the optical lens be cleaned with water and detergent as the lens’ surface is plated with a special film. Using water and detergent to clean the lens can damage its surface.

Keep the lens away from dark and humid environments as this can cause the lens surface to age.

Dust, dirt, or water vapor on the lens surface can easily absorb laser light and damage the lens coating, which can significantly affect the quality of the laser beam, and in severe cases, there would be no laser beam at all.

If the lens is damaged, contact the laser after-sales service department immediately to repair it. Avoid using the damaged lens, as this can accelerate the damage of the repairable lens.

When installing or replacing the reflector or focusing lens, avoid using excessive pressure, as it can cause deformation of the lens and affect the quality of the beam.

4. Methods of installation or replacement of optical lens

Please pay attention before installing optical lenses:

(1) Please wear clean clothes, wash your hands with soap or detergent, and wear clean and light-colored gloves;

(2) Do not touch the lens with any part of your hands;

(3) When removing the lens, please wear gloves and hold it from the side of the lens. Do not touch the lens coating surface directly.

When assembling the lens, avoid blowing air against the lens with your mouth. Instead, place the lens on a clean desktop with a few sheets of lens paper underneath. Take care when removing the lens to prevent it from getting scratched or falling, and do not apply any force on the coated surface of the lens. Ensure that the lens holder on which the lens is installed is clean, and remove any dust or dirt in the holder with a clean air spray gun. Then, gently place the lens in the holder.

When mounting the lens to the holder, do not use excessive force to fix the lens, as this may cause deformation and affect the quality of the beam.

Precautions to take when replacing optical lenses:

• Handle the lenses with utmost care to prevent any damage while removing them from the box.
• Do not apply any pressure on the lens until the wrapping paper has been removed.
• When removing the reflector and focusing lens from the box, wear clean gloves and pick them up from the side of the lens.
• While removing the wrapping paper, ensure that no dust or debris falls on the lens.
• After removing the lens, use a spray gun to remove any dust on the mirror surface, and then place the lens on a special paper meant for optical lenses.
• Clean the lens support frame and fixed frame to remove any dust or dirt, and make sure that no foreign objects fall on the lens during assembly.
• While installing the lens on the lens holder, avoid applying excessive force to prevent the lens from deforming.
• Once the lens assembly is complete, use a clean air spray gun to remove any remaining dust or foreign objects from the lens.

5. Steps for cleaning lens

Different lenses require different cleaning methods. For flat mirror surfaces without a lens holder, use lens paper to clean, such as when cleaning a reflector. However, for curved mirror surfaces or those with a lens holder, it is best to use a cotton swab, such as when cleaning a focusing lens.

Steps for cleaning a lens with lens paper:

(1) Use a blower to blow off any dust on the lens surface.

(2) Clean the lens surface with alcohol or lens paper. Do not use dry lens paper to directly drag it across the mirror surface. Instead, place the lens paper on the surface of the lens, add 2-3 drops of high-purity alcohol or high-purity acetone, and slowly pull the lens paper out towards the operator. Repeat this process several times until the mirror surface is clean.

(3) If the mirror surface is very dirty, fold the lens paper in half 2 to 3 times and repeat the above steps until the mirror surface is clean.

Steps to Clean a Lens with a Cotton Swab:

• Start by using a spray gun to blow off any dust on the mirror surface. Then, use a clean cotton swab to remove any remaining dirt.
• Use a new cotton swab that has been moistened with high-purity alcohol or acetone. Gently move the swab in a circular motion from the center of the lens to scrub it. After each circle, use another clean cotton swab and repeat the process until the lens is completely clean. Never reuse a cotton swab that you have already used for cleaning.
• Wash the lens with a clean cloth to remove any residue on the mirror surface. Be careful not to scratch the lens.
• Take the cleaned lens to a place with sufficient light to observe its reflection. If the reflection is clear, it means the lens has been properly cleaned. If the reflection is not clear, continue cleaning the lens.
• Finally, place the cleaned lens on a lens holder according to the appropriate method.

6. Daily maintenance of laser

Before switching on the laser, it is important to perform daily maintenance checks to ensure optimal performance.

• Inspect the laser working gas and cutting gas cylinders.
• Verify that the cooling water pressure is within the range of 3.5 to 5 Bar.
• Check the temperature of the cooling water, ensuring it is the appropriate temperature required by the selected laser.
• Verify the oil level in the laser vacuum pump and add more if necessary.
• Check for any possible leakage in the oil, water, and gas pathways of the laser, as well as any potential leaks in the pneumatic components, pipe joints of the vacuum pump, and resonant cavity.

7. Weekly maintenance of the laser

• Please check the laser’s gas mixing unit for any oil or water. If there is any, kindly clean it immediately. Also, ensure that you inspect the laser gas drying filter, and if the color changes more than 1/4th to red or white, it needs replacement. Usually, its normal color is blue.
• Please check the oil levels of the vacuum pump and Roots pump, and if it’s insufficient, kindly add more oil.
• Please inspect the chiller filter for any impurities.
• Please check the laser cooling water circuit for any impurities.
• Please ensure that you check the compressed air separator’s condensate water level (located in the air supply unit).
• Please inspect the vacuum pump oil level, located under the air supply unit. When the pump is cold, the oil level should be between + 5mm – 0mm of the oil window middle line. Please add more oil if required.
• Lastly, check the oil level of the Roots pump. You can see the oil level in the gear box of the Roots pump through the oil window on the end face of the gear box. When the pump is turned off and cold, the oil level should be between + 5mm and 0mm of the glass center line. If needed, kindly add HTCL2100 oil.

By implementing a comprehensive maintenance routine, operators can maximize the efficiency, reliability, and lifespan of the laser cutting machine while ensuring safe and consistent cutting performance.