Fiber laser welding machines are widely used in industrial production, but various problems are inevitable during use. The following summarizes common failure phenomena, cause analysis, and corresponding solutions, hoping to help you better use and maintain your fiber laser welding machine.
I. Welding Cracks in Fiber Laser Welding Machines
Cause Analysis:
- The workpiece surface is not clean, with oil stains, oxide layers, and other impurities.
- The workpiece assembly gap is too large or there are burrs, leading to concentrated welding stress.
- The cooling rate after welding is too fast, generating large thermal stress.
- The protective gas flow rate is too high, accelerating cooling.
Solutions:
- Thoroughly clean the workpiece surface before welding with the fiber laser welding machine.
- Improve the workpiece’s machining accuracy, reduce assembly gaps, and remove burrs.
- Appropriately increase the cooling water temperature to slow down the cooling rate (adjust on the fixture).
- Appropriately reduce the flow rate of the shielding gas used with the fiber laser welding machine.
II. Insufficient Welding Penetration in Fiber Laser Welding Machines
Cause Analysis:
- Insufficient laser energy.
- Inaccurate focusing position.
Solutions:
- Appropriately increase the pulse width or current of the laser to increase the laser energy.
- Adjust the focusing lens so that the focal point is on or slightly below the workpiece surface when using the fiber laser welding machine.
III. Blackened Weld Seam in Fiber Laser Welding Machines
Cause Analysis:
- The protective gas flow direction is incorrect, resulting in insufficient protection of the welding area and oxidation.
Solutions:
- Adjust the nozzle direction of the protective gas to ensure that the airflow is opposite to the welding direction of the workpiece, effectively isolating the air during fiber laser welding.
IV. Weakened Spark During Fiber Laser Welding
Cause Analysis:
- The focusing lens or laser resonator film is damaged or contaminated, reducing the laser output power of the fiber laser welding machine.
- The laser beam is not output from the center of the copper nozzle under the focusing head, resulting in energy loss.
- The main optical path laser beam is offset, affecting the transmission of laser energy within the fiber laser welding machine.
- The cooling water is polluted or has not been replaced for a long time, affecting the normal operation of the laser.
Solutions:
- Replace or clean the focusing lens and laser resonator film in a timely manner.
- Adjust the 45° reflecting diaphragm so that the laser beam is output from the center of the nozzle.
- Adjust the total reflection and semi-reflection diaphragms of the main optical path, check the spot position with image paper, and correct it.
- Replace the cooling water and clean the ultraviolet glass tube and xenon lamp within the fiber laser welding machine’s system.
Hope the above is helpful!