In general, the important process parameters affecting the processing quality of fiber laser cutting machine are cutting speed, laser power, auxiliary gas, focus position, nozzle characteristics and material properties. The research shows that there are many factors affecting laser cutting. If the control is improper or the parameters are not mastered, the cutting accuracy and quality will be greatly affected.

Now let's take a look at the common problems and solutions of fiber laser cutting machine in daily processing~

In the actual processing process, various poor cutting phenomena may be encountered. Take the small nozzle with high power for oxygen carbon steel and high-speed bright cutting technology as an example, the following situations may be encountered:

Optical fiber laser cutting machine

Stripes on the upper layer of the plate and drag lines on the lower layer are too rough

Possible causes:

【1】 Excessive nozzle selection;

【2】 Excessive cutting air pressure causes excessive burning;

【3】 Too slow cutting speed causes excessive burning or too fast cutting causes insufficient cutting;

Solution:

【1】 Replace the nozzle with a small diameter. For example, 1.4D nozzle is used for bright cutting of 16mm carbon steel, and 1.6D nozzle is used for bright cutting of 20mm carbon steel;

【2】 Reduce the air pressure to improve the quality of cutting section. Generally, the air pressure demand for bright cutting is 0.6~0.8 Bar.

【3】 Adjust the cutting speed to the appropriate range of the current power (see the cutting parameter table of Longtai continuous laser series for details)

Optical fiber laser cutting machine

The stripe on the upper layer of the plate is slightly rough, and the lower layer of the mouth is slightly or deeper, and the trailing line is better

Possible causes:

【1】 Excessive nozzle selection;

【2】 Insufficient forward defocusing;

【3】 Slow cutting speed;

Solution:

【1】 To achieve full brightness of the section, consider replacing the nozzle with a smaller diameter, for example, replacing 1.6D with 1.4D;

【2】 With the nozzle diameter unchanged, increase the forward defocusing;

【3】 Adjust the cutting speed to the appropriate range of the current power (see the cutting parameter table of Longtai continuous laser series for details)

Optical fiber laser cutting machine

The upper layer of the plate section has good stripes, but the bottom has slag and affects the section effect

Possible causes:

【1】 The forward defocusing is too large, resulting in the energy concentration is not concentrated and the lag tail is formed;

【2】 Too small air pressure causes drag line formed by cutting tail to lag and produce slag;

【3】 Too fast cutting speed leads to hysteresis;

Solution:

【1】 Reduce the forward defocusing appropriately, and keep the other parameters unchanged. Observe the slag hanging at the bottom;

【2】 Increase the feed air pressure appropriately, try to increase it to about 1 Bar at most, and observe the situation;

【3】 Adjust the cutting speed to the appropriate range of the current power (see the cutting parameter table of Longtai continuous laser series for details)

During the actual processing of the optical fiber laser cutting machine, when cutting nitrogen stainless steel, some common problems:

Optical fiber laser cutting machine

When cutting stainless steel medium and thin plates, the cutting section is rough

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Possible causes:

【1】 Too much negative defocusing leads to plasma, blue light and delamination;

【2】 The nozzle diameter is too small;

【3】 Excessive pneumatic feed;

Solution:

【1】 Reduce the negative defocusing, keep the other parameters unchanged, and observe the phenomenon;

【2】 Replace the nozzle with a larger diameter;

【3】 Properly reduce the pneumatic feeding;

Optical fiber laser cutting machine

The cutting section of stainless steel plate does not reach the bottom of the plate in case of insufficient cutting

Possible causes:

【1】 The nozzle is too small;

【2】 Insufficient negative defocusing;

【3】 Insufficient gas pressure, resulting in insufficient cutting.

Solution:

【1】 Replace the nozzle with a larger diameter to increase the gas flow;

【2】 Continue to increase negative defocusing to make the cutting section reach the bottom;

【3】 Continue to increase the air pressure;

Optical fiber laser cutting machine

The effect of adjusting the air pressure and the positive and negative defocusing amount is not obvious

Possible causes:

【1】 When the speed cannot be improved, the laser energy is too concentrated and the reaction with the material is too violent;

【2】 The nozzle selection diameter is too small, resulting in too small flow;

Solution:

【1】 Under the condition that the peak power remains unchanged, reduce the frequency and duty cycle appropriately. For example, when cutting 50mm stainless steel, if the speed cannot be increased, consider adjusting the frequency to about 200Hz. If the duty cycle is 55~65%, a better cutting effect can be obtained;

【2】 Replace the nozzle with a larger diameter to improve the gas flow;