Optical fiber laser cutting machine has two ways of perforating:
Select a high-power pulse laser to melt or vaporize a small number of materials. Air or nitrogen is commonly used as auxiliary gas to reduce the hole expansion due to exothermal oxidation. The gas pressure is lower than the oxygen pressure when the hole is cut.Each pulsed laser produces only a small particle eruption, which deepens gradually, so that the perforation of the thick plate takes several seconds at a time.Once the perforation is complete, an auxiliary gas is replaced with oxygen to make the incision.The perforation is smaller in diameter and better in quality than explosion perforation.Therefore, the laser used should not only have high output power, but also the time and space characteristics of the beam.In addition, a reliable air route control system is required to complete the control of gas variety, gas pressure switching and perforation timing.
The material is illuminated by a laser connected to form a pit in the middle, and then the molten data is quickly removed by a flow of oxygen coaxial with the laser beam to form a hole.Usually the size of the hole is related to the thickness of the plate, the uniform diameter of the explosion hole is half of the thickness of the plate, so the thicker the plate explosion hole diameter is larger, and not round, should not be used in the processing accuracy of higher demand parts, can only be used on the waste.In addition, the oxygen pressure used in the perforation is the same as that when the incision is made, the splash is larger.
1. Burr occurs during laser processing of stainless steel and aluminum-zinc coated plate
In this case, we should first consider the burr when cutting stainless steel elements, can not simply accelerate the speed of cutting, because the speed of addition will sometimes appear plate cut not open, especially in the processing of aluminum zinc steel plate this phenomenon is particularly prominent.At this time, should consider other elements of the optical fiber laser cutting machine to solve, such as whether to replace the nozzle, guide motion is not stable.
2. Analysis of pore deformation during cutting and processing
This is because the machine tool does not adopt the method of explosion perforation in the processing, but USES the method of pulse perforation, so that the laser energy is too concentrated in a small area, the non-processing area is also burned, leading to the deformation of the hole, affecting the processing quality.At this time, the pulse perforation method should be changed to explosion perforation method in the processing.On the contrary, for the optical fiber laser cutting machine with low power, the method of pulse perforation should be adopted to obtain better surface finish.
3. Solutions for abnormal sparks in low carbon steel processing
This condition will affect the cutting and section finish of the parts of the processing quality.At this point, when other parameters are normal, the following questions should be considered:
1. Loss of laser head nozzle?The nozzle should be replaced in time.In the absence of a new nozzle to replace the situation, should increase the cutting operation gas pressure;2. Loose thread at the connection between nozzle and laser head?At this moment should immediately pause the cutting, check the laser head connection status, top thread from the head.
4. The reason why the workpiece appears burrs when the laser cuts low carbon steel
There are several reasons:
1. If the upper and lower orientation of the laser focus is incorrect, the focus orientation test should be done and adjusted according to the offset of the focus;
2. The output power of the laser is not good, it is necessary to check whether the operation of the laser generator is normal. If normal, investigate whether the output value of the laser control button is correct, and then adjust it;
3. The linear speed of cutting is too slow, so it is necessary to increase the linear speed during control;
4, the purity of cutting gas is not good, need to supply high quality cutting gas;
5, laser focus shift, need to do focus azimuth test, according to the focus of the shift to adjust;
6, the machine running time is too long instability, now need to shut down and restart.
5. The condition that the laser has not been completely cut through
The selection of laser head nozzle does not match the thickness of machining plate;The linear speed of laser cutting is too fast, so the linear speed should be reduced during control.It is necessary to test the nozzle induction data from head to head, especially the simplest presentation when cutting aluminum.