The cnc laser metal sheet cutting problems and solution
In the process of cnc laser cutting sheet metal, various problems are often encountered, the following are common problems and solutions.
Table of Contents
CNC sheet metal laser cutting processing small hole deformation
Problems: When processing small holes in high-power cnc laser cutting machines, the use of cnc pulse perforation (soft piercing) makes the laser energy too concentrated in a very small area, which will also scorch the non-processing area, causing deformation of the hole and affecting the processing quality.
Solution: For small hole deformation in sheet metal cnc laser cutting processing, we should change the pulse perforation (soft piercing) method to blast perforation (ordinary piercing) method in the processing program to solve the problem. For the smaller power cnc laser cutting machine is the opposite, in the small hole processing should take the pulse perforation way to obtain a better surface finish.
Solutions for burrs in cnc sheet metal cutting workpiece
Problem:cnc sheet cutting process often has unsmooth edge burrs
Solution: According to the working and design principle of CO2 laser cutting, the following reasons are analyzed to be the main causes of burrs on processed parts.
- (1) The upper and lower positions of the cnc laser focal point are not correct, so it is necessary to do a test of the focal point position and adjust it according to the offset of the focal point;
- (2) The output power of the cnc sheet cutting is not enough, you need to check whether the work of the laser generator is normal, if normal, then observe whether the output value of the laser control button is correct, to adjust;
- (3)Cnc sheet cutting cutting line speed is too slow, need to increase the line speed in the operation control.
- 4) The purity of the CNC cutting gas is not enough, the need to provide high-quality cutting working gas.
- (5) Laser focus shift, the need to do focus position test, according to the amount of focus shift to adjust;
- (6) The instability of the CNC laser machine too long running time, at this time need to shut down the machine to restart.
Laser can not completely cut through metal sheet
Problem: The sheet metal cutting process machine operation is unstable, the sheet metal is not completely cut through.
Solution: After analysis, the following situations can be found to be the main ones that produce unstable processing.
- 1) Mismatch between the selection of the laser head nozzle and the processing plate thickness.
- 2) The laser cutting line speed is too fast and requires operational control to reduce the line speed.
- (3) In addition, special attention should also be paid to the L3030 laser cutting machine cutting more than 5mm carbon steel plate need to replace the 7.5″ focal length of the laser lens.
Cutting mild steel when there are abnormal sparks solution
Problem: abnormal sparks when cutting mild steel, this situation will affect the quality of processing of the cut section finish of the part.
Solution: In the case of other parameters are normal, the following should be considered: the loss of laser head nozzle, the nozzle should be replaced in a timely manner. In the absence of a new nozzle replacement, the cnc laser cutting working gas pressure should be increased; nozzle and laser head connection at the thread is loose. In this case, the cnc fiber laser cutting should be immediately suspended, check the cnc laser head connection status, and rethread.
Laser cutting process when the choice of puncture point
The laser beam working principle during laser cutting process is that, the material is irradiated by continuous laser light to form a crater in the center, and then the molten material is quickly removed by the cnc laser working gas stream coaxial to the laser beam to form a hole. This hole is similar to a wire-cutting hole, where the cnc laser beam is used as the starting point for contour cutting.
Therefore, when the laser beam begins to penetrate the steel plate to enter the part contour cutting of this period of time, its cutting speed in the vector direction will have a great change, that is, the vector direction of 90 ° rotation, from perpendicular to the cutting contour of the tangent direction to the cutting contour of the tangent line coincident, with the contour tangent angle of 0 °. This leaves a relatively rough cutting surface on the cut section of the processed material, which is mainly due to the rapid change of the vector direction of the laser beam in the movement within a short period of time. Therefore, attention should be paid to this aspect when using cnc laser cutting to process parts. Generally, in the design of the parts on the surface of the cut section no roughness requirements, you can do not do manual processing in the laser cutting programming, so that the control software automatically generate puncture points; However, when the design of the parts to be processed when the laser machine cut section has high roughness requirements, we need to pay attention to this problem, usually need to do manual adjustment of the starting position of the fiber laser beam when the laser cutting program, that is, manual control of the puncture point. This is the manual control of the puncture point. It is necessary to move the original puncture point generated by the laser program to the required reasonable position in order to achieve the required surface accuracy of the machined part.