Illustrations of Inspection for 10kW+ Laser Cutter Before Operation

In order to ensure the normal operation of high power laser cutting machines and good processing quality, therefore, we should do relevant inspection before daily operation.

 

1. check the cleanliness of the lens  

Cutting head lens is very important to 10kw+ laser cutting machine, and its cleanliness directly affects the processing performance and cutting quality. If the lens is dirty, it will not only affect the cutting process, but also further damage the internal cutting head. Checking in advance before cutting can avoid serious loss.  

 

A red light detector is usually used to check if lens is clean, which requires a single layer of nozzle with a diameter of 2.0mm or higher and a piece of white paper.  The steps are as follows:  

 

① red light indication is on when Senfeng 10kW+ laser cutter boots ;  

② the distance between white paper and cutting head nozzle should be about 300mm above in order to see the red light;  

③ If there are obvious contours of black spots or irregular black objects in the red light, the lens is dirty and needs cleaning before cutting and debugging  

 

2. Coaxial debugging  

The coaxiality of the nozzle outlet and the laser beam is one of the most important factors affecting the quality of cutting. If the nozzle is a little not coaxial with the laser, it only affects the consistency of the cutting surface. If the deviation is severe, the laser will hit the nozzle, causing it to burn.  

 

Coaxial debugging requires a 1.2mm diameter nozzle and Scotch tape.  The steps are as follows:  

 

① adjust the coaxial focus at 0, so that the laser is in the center of the nozzle;  

② red light within focal point ±6mm;  

③ if the red light of 0 and ±6mm are in the center of the nozzle, it is ok to operate.  Otherwise, the optical path of the laser is abnormal, you should replace the cutting head.

 

 

3. check the spot distribution  

The spot shape directly reflects the transverse distribution of laser energy.  Spot roundness indicates the uniformity of energy distribution of the spot in different directions. The energy distribution of the spot with high roundness is consistent in all directions. When cutting, it can ensure the consistency of the surface in all directions to make sure the quality is good even with fast cutting speed.

 

To check the spot distribution, you should prepare a single layer nozzle with a diameter above 2.0mm and black paper.  The steps are as follows:  

① Distance between black light spot paper and cutting head nozzle should be about 300mm, open shutter and click laser  

② If there are obvious black dots in the light spot, the lens is dirty;  

③ If the spot is not round and the center is offset, the laser spot is poorly distributed. 

 

 

4. the actual zero focus detection  

Laser cutting focus position is a very important data in the cutting process parameters. When you cut different material and thickness, different focus need to be adjusted. Before cutting, the actual zero focus can be referred to default parameters, to help determine the most appropriate cutting focus. If the actual zero focus offset is too large, the cutting range will be insufficient to cut the thick plate.  

 

Detection method:  

 

① fixed cutting height of 0.5mm; for every change 0.5mm focus position, cut a line on 1mm stainless steel;  

② Comparing the line width of different focus positions, and the one cutting the minimum line width is the actual zero focus;  

③ the actual zero focus should be within the range of ±1, if the zero focus offset is too large, you need to adjust or replace the cutting head.  

 

5. Test the nozzle heating range

Options for 10kW when cutting carbon steel

Thickness	Gas	Nozzle size	Cutting effect
1-12mm	Air	1.5-40.mm	matte
14-16mm	O2	1.2-1.4MM	Smooth
18-30mm	O2	1.4-1.6mm	Smooth
32-50mm	O2	1.8mm	matte

 

The biggest problem of cutting carbon steel thick plate is that the nozzle is always over heated. So before cutting, it is necessary to test nozzle heating of the different size in different focus positions when it works with full power.  

 

Test premise:  

① adjust coaxiality, so that the spot output is in the center of the nozzle;  

② install nozzle cooling gas;  

 

Test method:  

 

① put an iron bucket under the cutting head (with the right amount of water);  

② blow auxiliary gas (gas type and pressure should be according to the actual cutting requirement), measure the nozzle temperature change after working full power for 30 seconds,  then change the focus position and continue the test as above;  

③ change the nozzle size and continue the test according to the above method;  

④ summarize the heating conditions of different nozzles to provide reference for subsequent cutting process debugging.  If the heat range is very narrow, then check if there are problems from the cutting head, nozzle, lens and laser. Troubleshoot problems before the next step of cutting plate process debugging.  

 

Senfeng, as a comprehensive laser solution provider, not only provide the equipment with superior performance, but also help you to ensure the normal operation of the high power laser cutting machines after your purchase. We have a great knowledge pool on laser and other solutions to upgrade your fabricating machinery process, please feel free to contact us on any topics that can help with your business.

 

Whatsapp: 86-13210546543

E-mail: senfeng@sfcnclaser.com