Common problems of laser cutting machine

Common problems of laser cutting machine

1. Burrs appear on the edge of the workpiece during laser cutting

When laser cutting carbon steel, burrs sometimes appear on the edge of the workpiece, making the surface look uneven, and some are difficult to remove, mainly caused by the following points:

1. The upper and lower positions of the laser focus are not correct, and a focus position test needs to be done and adjusted according to the offset of the focus;

2. The nozzle selection is inappropriate, replace the nozzle;

3. The purity and pressure of the cutting gas are not enough, and it is necessary to provide high-quality cutting working gas and increase the air pressure;

4. If cutting a quadrilateral, there are burrs on the two adjacent sides, indicating that the center of the light path has shifted, and you need to teach the center point of the light path from the nozzle again; if there are burrs on the two parallel sides, it means that the laser head is installed There is a problem with the verticality on the machine tool. You can teach the installation verticality of the laser head according to the burr direction of the parallel side; please check whether the roundness of the nozzle opening of the nozzle has changed, and it must be ensured that the roundness of the nozzle opening is a full circle .

Second, the laser cutting sheet can't cut through

1. The power drop of the laser or the aging of the lamp tube makes the energy of the laser beam insufficient, causing the template to be cut through. Need to adjust the laser power to replace the laser generator tube;

2. The cutting speed is too fast, choose a suitable cutting speed according to the thickness of the cut sheet;

3. Check whether the output air pressure of the proportional valve is consistent with the cutting air pressure set by the host computer, and whether the oxygen meter is at the 10 kg indication;

4. Check whether the protective lens is damaged, and replace the protective lens;

5. The focus position is inappropriate, adjust the focus position according to the thickness of the sheet;

6. On the premise that there is no problem with the protection lens and the cutting speed and air pressure, check whether there is any problem with the optical fiber interface. If there is no problem with the optical fiber interface, please check whether the collimating lens and focusing lens of the laser cutting head are damaged. , Please replace it in time.

3. Rough surface of laser cut sheet

For carbon steel: the top surface texture is too rough, indicating that the cutting focus is too far away from the plate, and the focus needs to be adjusted closer; the bottom surface is too rough, indicating that the cutting gas pressure is too large, reducing the gas cutting pressure; the overall texture is too rough, indicating that the cutting speed is too high Slow, increase the cutting speed.

Fourth, the centering is easy to shift in laser cutting processing

cause of issue

1. The optical fiber is loose.

2. The problem of adjusting the module.

3. The ceramic body is loose.

4. The nozzle is loose.

Troubleshooting plan

1. Check whether the optical fiber is locked tightly.

2. Contact the cutting head manufacturer.

3. Check whether the ceramic body and nozzle are locked, if they are loose, they need to be re-reinforced.

Five, optical fiber interlocking alarm

cause of issue

1. The optical fiber is not installed properly.

2. QBH internal contact problem.

3. The laser fiber connector problem.

Troubleshooting plan

1. Re-lock the optical fiber according to the instructions of the cutting head.

2. Contact the cutting head manufacturer to deal with

3. Contact the laser manufacturer to deal with

6. Abnormal cutting effect

cause of issue

1. Whether the cutting parameter call is correct.

2. Whether the cutting focus is adjusted correctly.

3. The problem of cutting air source.

4. The cutting head lens problem.

Troubleshooting plan

1. Check the cutting parameters and cutting focus position.

2. Check whether the gas is sufficient and the gas purity.

Observe the barometer on the gas cylinder according to the selected cutting gas (O2, N2). If the oxygen is about 10 kg, check whether the output gas voltage value of the cutting system corresponds to the value displayed by the gas proportional valve, generally 10V corresponds to 10 kg; Nitrogen needs to be adjusted according to the thickness of the cut sheet. The purity can be satisfied by checking the label of the gas cylinder to satisfy the purity above 99.9%. If nitrogen is used for cutting, it can also be tested by cutting the end face of stainless steel. The end face is yellow and the purity is low, and the high-purity gas needs to be replaced immediately.

3. Take out the protective lens and check if there is any pollution. If there is pollution, the lens needs to be cleaned.

4. Check whether the lens and fiber end face of the cutting head are normal according to the method in the third troubleshooting plan. If the position is not correct, adjust it to the correct position.

Seven, the focusing dial cannot be adjusted

cause of issue

1. The focusing stroke is exceeded during the focusing process.

2. The damage of the sealing ring at the position of the protective lens seat causes the auxiliary gas to enter between the focusing module and the protective lens.

Troubleshooting plan

1. Check whether the focusing range has been exceeded. If it exceeds the focusing range, first loosen the locking screw at the position where the signal amplifier is installed on the left side of the cutting head, and then try to adjust and re-tighten the screw.

2. Check whether the sealing ring with steel ring under the protective lens is damaged. If it is damaged, replace the sealing ring.

8. Abnormal capacitance value alarm

cause of issue

1. The ceramic body is damaged or loose.

2. The nozzle is damaged or loose.

3. The nozzle connecting body is touched and damaged.

4. The signal line problem.

Troubleshooting plan

1. Check whether the ceramic body and nozzle are damaged or loose. If they are damaged or loose, replace and reinforce them.

2. After removing the ceramic body and nozzle, check whether the contact at the installation position of the ceramic body of the cutting head is damaged. If damaged, contact the supplier for replacement.

3. Check whether the signal wire is disconnected.

If there is no obvious damage, you can use a multimeter to do a specific inspection under the guidance of an after-sales engineer.

Nine, the nozzle temperature is too high during processing

cause of issue

1. Alignment offset.

2. Protect the lens from pollution.

3. The focusing lens or collimating lens is contaminated.

4. Optical fiber pollution.

Troubleshooting plan

1. Check whether the alignment is offset, and adjust if there is any offset.

2. Take out the protective lens for inspection. Note that after taking out the protective lens holder, be sure to use masking paper to seal the leaking position of the cutting head. Never blow after taking out the protective lens holder. If the protective lens is contaminated, it needs to be cleaned.

3. Check the optical lens inside the cutting head.

Lift the cutting head to the highest position, turn on the red light, unscrew the nozzle, place a piece of white paper within the 20-40mm position of the lower end of the ceramic body, and move it up and down to observe the uniformity distribution of the red light. When observing the red light, try to shield the periphery of the red light to ensure a certain contrast, and the observation can be clearer. If there are obvious black spots, it can be judged that the internal focusing or collimating lens or the end face of the fiber is contaminated. This requires contacting the after-sales service engineer for guidance. Do not disassemble the laser head without authorization, and do not continue to use it to avoid greater damage. .