Quality Control of Sheet Metal Laser Cutting

The laser cutting machine is preset with reference cutting parameter values of various materials and various thicknesses. Generally, it can be directly selected for cutting after calling the cutting program. However, because the railway trucks are all medium and heavy plates, the cutting quality is often poor, and the phenomenon of impermeability and slagging occurs. For this situation, the operator is more headache, so how can we improve the quality of sheet metal laser cutting? The general factors are divided into four categories:

1. Laser generator: output power, laser mode, laser polarization, beam parallelism, laser straightness; among them, only the output power can be properly adjusted within the rated range, and the other influencing factors are mainly guaranteed by the quality of the equipment and the specific selection.

2. Cutting head: suitable cutting lens, clean cutting lens, accurate focus position, nozzle type, nozzle size, whether the beam is in the center of the nozzle. Different cut lenses are used for plates of different thicknesses. Manufacturers generally provide 5-inch, 7.5-inch, and 10-inch focusing lenses. In addition to Japanese manufacturers, lens manufacturers are generally American companies. Before each sheet metal laser cutting, the operator should clean the lens, select a suitable nozzle, and check whether the cutting head is perpendicular to the sheet to be processed.

3. Programming: reliable cutting path, pre-cutting. The cutting program setting path should be as simple as possible, pay attention to setting the micro-connection and other functions; it is best to perform a pre-cut before cutting to determine whether it is correct.

4. Suitable process parameters: puncture point, nozzle height, power, cutting speed, auxiliary gas purity, and outlet pressure. If the puncture point is on the contour line of the part, there will still be obvious burn marks, so it is better to start arc tangent on the outside of the contour line.

In fact, the biggest factors affecting the quality of sheet metal laser cutting are the purity of the auxiliary gas and the outlet pressure, cutting speed, and focus position. It is recommended to select auxiliary gas with higher gas purity as much as possible. On this basis, try to increase the auxiliary gas outlet pressure, adjust the cutting speed, and finally try to change the focus position for gradual adjustment. When the cutting quality is stable, it will be solidified into the processing parameters and numerical control program, but be careful not to destroy the original parameters, you should save a new one instead.