15.Laser Cutting Machine Focus Adjustment and Select of Cutting Speed-Ella
Laser Cutting Machine Focus Adjustment and Select of Cutting Speed
1.The adjustment of laser cutting machine focusing points
It is very important to adjust focus point properly in the process of laser cutting
because relative position between laser beam focus and the surface of work piece have a great influence on cutting quality.
We can try to cut by changing the focus point, when there is no dross on the back of sheet plate and slit is the finest,
that is the focal point position according to the sheet plate.
If relative position of the cutting head and the plate surface changes,
cutting head and sensor zero point also need to change accordingly,
micro adjust of the cutting height can be finished by software to finish;
if need large adjustment, need change relative position of the sensor and the bracket to realize focus point adjustment.
When doing this work, operator must be very careful,otherwise cutting head is likely to go down and collision,
it will lead damage to spare parts.
2.The relationship between focal position and cutting result
| Name and focus position | The material and cutting edge features |
| 0 focal length: focal point at the surface of work piece | For carbon steel
focal point at the surface of workpiece, the top surface of cutting result is smooth while the down surface is not very smooth. |
| + focal length: focal point inside of work piece | For Aluminum material
Focus point at the center, therefore range of smooth surface is larger, cut area is wider and piercing time is longer than at 0 focal length, gas flow rate is greater when in process of cutting. |
| – focal length: focal point below at the work piece | For stainless steel
When cutting the stainless steel with high-pressure nitrogen gas, blow slag and protect section, cut area increasing along with the thickness of the workpiece. |
3.The selection of cutting speed
The selection of cutting speed is based on material and the thickness of the sheet,
different cutting speed will cause a great impact on the laser cutting quality.
Select the appropriate cutting speed, can not only improve the work efficiency of laser cutting,
but also get a better cutting quality. Here we discuss the effects of different cutting speed for cutting quality:
a)The laser cutting feed speed is too fast
1) It may cause sparks flying so that it can not be cut.
2) It may cause some regions may be cut off, but some areas can not be cut off.
3) It may cause the whole cutting section too thick, but no melt slag.
4) It may cause the plate can not be promptly cut off,
cutting section presents diagonal stripes, and the down surface cause lower melt slag. As below shown:
b) The laser cutting feed speed is too slow:
1) It will cause steel sheet excessively melting phenomenon, cutting section is too rough.
2) The slit will become wider accordingly,
also it will cause the whole region melt on a lesser rounded part or sharp corner part,
so the user cannot get ideal cutting result.
3) Cutting efficiency is low, so it will affect the production capacity.
4) Choice of proper cutting feed speed：
we can judge the feed speed from the cutting sparks：
Generally the cutting spark diffuse from the top-down，
the feed speed is too fast when the spark slant；
if the spark not diffuse and very less,keeping together,then it prove that feed speed is too slow.
Proper cutting speed,the cut surface show the more smooth line,
and no melting stains occurs in the lower half , same as the following picture:
If you have any questions about laser cutting machine, please feel free to contact us any time.
