Laser welding head maintenance must be carried out by specially trained personnel, otherwise serious man-made damage can easily occur.
1) In order to ensure that the laser head is always in normal working state, after the laser head that has been working continuously for two weeks or more has stopped for a period of time, the components in the optical path, such as the YAG rod and the dielectric diaphragm, should check the lens protective glass before starting to ensure that each There is no dust contamination, mold and other anomalies in the optics. If this phenomenon occurs, it should be dealt with in time to ensure that each optical element will not be damaged under strong laser irradiation. (If the operating environment of the equipment is relatively clean, the above inspection can be extended to a month or more.)
2) The purity of the cooling water is the key to ensure the output efficiency of the laser head and the service life of the laser head condensation cavity components. During use, the conductivity of the inner circulating water should be checked once a week to ensure that its conductivity is 30.5MW·cm. The inner circulating deionized water must be replaced once a month, and the conductivity of the newly injected pure water must be 32MW·cm. Observe the color change of the ion exchange column in the cooling system at any time. If the color of the resin in the exchange column turns dark brown or even black, replace the resin immediately.
3) The equipment operator can usually use black image paper to check the output point of the laser. When the light spot is uneven or the energy drops, the resonant cavity of the laser head should be adjusted in time to ensure the quality of the beam output by the laser head. A typical spot image is as follows: adjust the laser head resonator, adjust the spot but not adjust the spot.
Warning: This product is a Class 4 laser head device. The laser irradiation of the strong laser head can cause serious damage to human skin, especially blinding eyes. Commissioning operators must have general knowledge of laser welding head safety protection and must wear special laser safety glasses with a wavelength of 1.064mm during work.
Note: When a strong laser directly irradiates flammable materials such as wood, an open flame will occur. During the debugging process, a piece of ferrous metal material with good absorption properties should be placed on the optical path output by the laser head as a beam terminal to prevent fire accidents.
Laser head adjustment must be performed by specially trained personnel, otherwise other components on the optical path will be damaged due to misalignment or misalignment of the laser head.
The adjustment steps of the resonant cavity of the laser welding head are as follows:
1. Check the reference light source
The red semiconductor laser head is the reference for the entire optical path, and its accuracy must be ensured first. Use a simple altimeter to check that the red light is parallel to the top surface of the optical table rails and the centerline between the two rails of the optical table. If there is any deviation, it can be adjusted by 6 fastening screws. After adjustment, be careful to double check that all fastening screws are fully tightened.
2. The laser welding head adjusts the position of the output mirror (output medium diaphragm)
Before adjusting the output mirror of the laser welding head, the condenser cavity equipped with the YAG rod should be removed to avoid the refraction deviation of the YAG rod in the optical path affecting the adjustment accuracy. The exact position of the output medium diaphragm should be the exit hole, so that the red light is at its center, and the red light can be completely reflected back to the red light, otherwise it should be carefully adjusted by the knob. Diaphragm seat. Please note that after the laser welding head is adjusted, the locking ring on the diaphragm frame adjustment knob should be fully locked to ensure the stability of the position of the laser welding head, and then check again that the position of its reflected light remains in place.
3. Check the installation position of the YAG rod
Paste transparent tape on both ends of the YAG pole sleeves respectively, and observe whether the red light spot is located in the right middle position of the two pole sleeves. If there is any deviation, it should be corrected by adjusting the position of the condensation chamber. Then observe the position of the reflected light from the YAG rod, which should coincide with the red light exit hole. Otherwise, adjust the position of the condensation chamber so that the reflected light is as close to the exit hole as possible, while keeping the red light as centered as possible on the rod housing, and at least ensure that the deviation of the exit hole is less than 1 mm.
4. Adjust the position of the total reflector (total reflection dielectric diaphragm)
Step 1: Check if the red light is in the middle of the medium diaphragm, otherwise, adjust the installation position of the medium diaphragm so that the red light is in the center of the medium diaphragm.
Step 2: Roughly adjust the knob of the mid-diaphragm frame to reflect the red light back to the perforation.
Step 3: Open Badger Shine? ? What do you think? 00A, adjust the pulse width to about 2ms, adjust the repetition frequency to 0Hz, and step on the foot switch to flash the pulsed xenon lamp. At this point, put the fully exposed black image paper in front of the output mirror, and the laser welding head output can be observed. Repeatedly adjust the two knobs of the aperture frame to make the output light spot the most round and uniform, and then the current is gradually reduced to about 120A. The knob is further fine-tuned and carefully adjusted so that the spots of light where the farthest and strongest parts hit the image paper are as concentrated as possible in the center of the spot.
Step 4: Check whether the laser welding head is consistent with the red light, fix the image paper at the front of the output mirror of the laser welding head as far as possible from the output mirror, emit the laser head pulse, and observe whether the light spot is centered, and the image paper and the red light are in the same position. Centers coincide. If not, fine-tune the output mirror and total reflection mirror to make the light spot coincide with the red light, then fix the image paper at a position 800 - 1000 mm away from the output mirror of the laser head, and then check whether the light spot coincides with the red light. If the laser head can coincide well, the laser head will be adjusted to the best state.
Step 5: Lock each adjustment knob and double check that the light spot on the image paper is good and coaxial with the red light. Otherwise, it should be readjusted.
5. Check the shutter position
Manually rotate the reflector bracket, push the shutter to the blocking position, and observe whether the red light is in the middle of the lens, and whether the reflected light is on the absorption cone in the center of the end of the beam. If the position is not correct, fine-tuning can be done. Finally, take extra care to double-check that the shutter mirror is clean, contaminated lenses can break quickly when used. At this point, the adjustment of the laser components is completed. Maintenance of the cooling system 1 The main contents of the maintenance of the cooling system include checking the quality of the cooling water, cleaning the water tank and pipes, and checking whether the protection circuit is working properly.
If used frequently, the water quality must be checked weekly to ensure the quality of the cooling medium at all times. The inspection method is to place the multimeter in the 2MW#P# page heading #E# resistance file, and insert the bare metal parts of the two probe measuring ends into the cooling water surface in parallel at 1cm intervals. At this point, the resistance reading should be at least greater than 250kW. If the reading is below this value, the cooling water should be replaced immediately. 2 Check the protection chain circuit stainless steel electrode
According to the characteristics of the laser head equipment, the cooling system has specially designed protection measures, such as over-temperature sound alarm, over-temperature interlock, flow switch interlock, liquid level protection interlock, etc. During use, the above protection circuit should be checked frequently to ensure its normal and effective function. This can be checked by changing the water. Matters needing attention
In the high temperature and high humidity environment, attention should be paid to observe whether the "condensation" phenomenon caused by the low water temperature occurs in the cooling water circulation pipeline or the laser head condensation chamber during the working process of the laser head. The occurrence of "condensation" will cause damage to the end face of the YAG crystal, resulting in reduced output power or even no light. Care must be taken during use. If "condensation" occurs, stop using the laser welding tip immediately. After the moisture on the condensation chamber surface has naturally dried, the condition of the YAG optical surface should be rechecked to determine if the YAG rod should be cleaned. Only when everything is OK, the machine can be started again. Before starting the machine, care should be taken to appropriately increase the lower set temperature of the thermostat.
