With the rapid development of laser technology, the power of lasers and laser cutting equipment is getting higher and higher. The 12kw-60kw high powered laser cutter comes out. For users, based on the increase in power, they are not only concerned about the increase in sheet metal cutting thickness, but also the quality of sheet metal cutting.
This article comprehensively analyzes how to cut high-quality stainless steel thick plates from gas, process, and debugging:
Effects of different auxiliary gases on stainless steel cutting
| Parameter | Nitrogen Gas | Oxygen Gas |
|---|---|---|
| Source | Nitrogen gas cylinder | Oxygen gas cylinder |
| Cutting Effect | Silver-colored cutting surface | White-colored cutting surface |
| Supply Method | Stored in tanks | Supplied by air compressor |
| Pressure | > 3 Pa | > 3 Pa |
| Purity | 99.999999% | Standard purity (requires air purification) |
| Handling Equipment | Gas cylinder | Air compressor |
| Backend Treatment | N/A | Water and oil removal, filter replacement |
| Advantages | Low cost, long usage time, stable pressure | Low cost |
| Maintenance Requirements | N/A | Regular filter replacement, water/oil removal |
| Special Considerations | N/A | Must ensure purity to avoid contamination |
Analysis of high powered laser cutter stainless steel thick plate cutting process
The 10,000-watt laser cuts stainless steel of different thicknesses to ensure that the cutting section is fine and without delamination. Different cutting methods should be used:
| Parameter | Stainless Steel Thickness <= 25mm | Stainless Steel Thickness > 30mm |
|---|---|---|
| Cutting Method | Full Power Continuous Laser Cutting | Full Peak Power Pulse Cutting |
| Focus | Negative Focus | Positive Focus |
| Focus Adjustment | The thicker the material, the greater the negative focus | The thicker the material, the smaller the positive focus |
| Special Considerations | N/A | Pulse cutting for thicker materials |
Frequency changes
| Frequency | 500Hz | 400Hz | 300Hz | 200Hz |
|---|---|---|---|---|
| Duty Cycle | 55% | 55% | 55% | 55% |
| Power | Frequency (Hz) | Duty Cycle (%) | Single Pulse Energy (J) | Pulse Duration (ms) | Pulse Off Time (ms) |
|---|---|---|---|---|---|
| 12kW | 500 | 55 | 13.2 | 1.1 | 0.9 |
| 12kW | 400 | 55 | 16.5 | 1.375 | 1.125 |
| 12kW | 300 | 55 | 22 | 1.833 | 1.5 |
| 12kW | 200 | 55 | 33 | 2.75 | 2.25 |
Effect of frequency change: The frequency decreases from 500-200Hz, the cutting section effect becomes finer, and the layering gradually improves. When the frequency is set to 100Hz, it cannot be cut and blue light is reflected. Find the optimal frequency range by changing the frequency. To ensure the best cutting section, the number of pulses must perfectly match the energy of the single pulse.
Focus change
| Focus | Frequency (Hz) | Duty Cycle (%) |
|---|---|---|
| +7mm | 200 | 55 |
| +8mm | 200 | 55 |
| +9mm | 200 | 55 |
Effect of focus change: delamination of the lower section appears at focus +7mm, and the cutting surface turns yellow. As the focus rises, uncut traces of the lower surface become less delaminated. The focal width is about 2mm. When the focus rises to +10mm, cutting cannot be performed. Anti-blue light. Find the best surface focus position through the offset of the focus.
Duty cycle changes
| Frequency | 200Hz | 200Hz | 200Hz |
|---|---|---|---|
| Duty Cycle | 52% | 53% | 60% |
Influence of changes in duty cycle: 53% duty cycle is the critical value. If the duty cycle continues to be reduced, uncut traces will appear on the lower surface. When the duty cycle increases to 60%, the cross section becomes rough, the layering is obvious, and the cutting surface Yellowing.
Nozzle airflow changes (air pressure setting 21bar)
Influence of changes in nozzle airflow: Except for the diameter 2.0 nozzle, there is no significant difference in the effects of the other nozzles. A nozzle with a diameter of 8.0, set to 21bar, and the actual air pressure is 10bar, cannot cut normally. The thicker the stainless steel, the larger the nozzle should be used, the higher the air pressure setting, and the pressure and flow rate should be met at the same time to achieve normal cutting effects.
Stainless steel thick plate cutting and debugging method
- Nozzle Selection:
- Choose a nozzle based on the one provided by the customer.
- Confirm the actual air pressure required for the selected nozzle at the customer’s site.
- Frequency Control:
- Input the basic parameters for the system.
- Evaluate the cross-sectional effect and adjust the frequency accordingly, increasing or decreasing as needed.
- Duty Cycle Adjustment:
- Input the basic parameters for the system.
- Assess the cross-sectional effect and make adjustments to the duty cycle, increasing or decreasing as necessary.
- Focus Speed Adjustment:
- Achieve the desired cross-sectional effect.
- Increase the focus speed incrementally, fine-tuning until the optimum value for the fastest result is reached.
- Parameter Confirmation for Production:
- Finalize the operational parameters based on the adjustments made.
- Ensure that the duty cycle is above the critical threshold for effective production.
- Set the speed limit to 0.9, optimizing for the highest achievable speed.