More power = more profit also in laser cutting?
The laser machine market is experiencing dynamic change. It’s becoming apparent to the industry that the power limits of other beam-type cutting technologies such as CO2 laser, plasma, and waterjet don’t restrict fiber laser. For example, 4 to 6kW of power was considered sufficient for CO2 laser cutters, and more and more customers worldwide are finding great success with fiber laser power of 10 - 15kW and the first ones even with 20kW.
Eagle laser cutting machines have led the charge. Over the past 10 years Eagle has pioneered 6, 8, 10, 12, 15 and now 20kW. This document explains fiber laser technology and illustrates its future.
An important side note: Laser cutting machines basically remove material by either flame cutting (oxygen assist gas) or fusion cutting (nitrogen assist gas).
Flame cutting with oxygen is used only on certain materials, most commonly mild steel, and is effective up to about 10kW laser power; a further increase in laser power does not mean an increase in productivity. Fusion cutting with nitrogen has no such limitation. This article concentrates on fusion cutting.
How is high-power laser technology defined?
Although there is no official definition, there is a good reason to draw such a limit at 8kW laser power. The reason is that adding more power when cutting thin sheet metal of 1mm (.040”) and under provides no cut speed benefit – there is not enough material thickness to absorb more energy.
Is high-power laser technology only suitable for cutting thick materials?
Without doubt, more power increases maximum thickness capacity. Thickness of 60mm has been successfully processed with high-power laser technology. Although more power does enable thicker cutting, high-power lasers also reap great benefits on sheet metal materials, as long as they are thicker than 1mm (.040”) thick.
The main area of application is up to 25 mm (1”). With these material thicknesses, all the advantages of high-power laser technology are optimally exploited. Today we can safely say that more power automatically means higher productivity and lower unit costs.
"Tower of Power" - Laser power correlates to productivity
It is somewhat intuitive that laser power equals productivity. The Tower of Power example explains in concrete terms just how true this is. A typical part fabrication part is chosen:
|Material:||Mild steel St 37|
|Material thickness:||8mm (0.3”)|
|Cut length per part:||1975 mm (77.8”)|
|Total size:||210 x 287mm (8.3 x 11.3”)|
This example shows only a small part of the complex world of laser cutting technology. Varying material type, thickness, cut pattern, machine dynamic motion, and laser parameters will generate different results, however, the trend will remain.
More laser power increases the producing cutting speed practically linearly!
Not only does power equal productivity, it also relates to quality. For most applications, higher power puts less heat into the material due to the increased cut speed, thereby producing a better edge.
Higher cutting speed means shorter production times and higher productivity per hour.
As power increases, the number of units produced in an hour also increases. This result requires that you have a machine that delivers high dynamic motion: velocity and acceleration. The machine must be able to reach cutting speed (velocity) and come in and out of direction changes quickly (acceleration) so as not to limit the productivity.
For this test we used the Eagle iNspire® machine tool, which achieves a top velocity of 150m/min and an acceleration of 6g – as the quickest laser cutting machine in the world, it is more than enough to ensure machine motion has minimal impact on the test results.
Productivity naturally has an enormous influence on unit costs. In order to be able to determine the unit costs, we have allocated the following machine-hour costs to the machine depending on the laser power.
The 100 EUR total hourly cost is chosen as a typical cost for operating a 4kW laser. This is not the amount a shop would charge to perform work on the machine, it is the total operating cost. Total operating cost includes machine operating cost, labour, overhead, and machine payments/depreciation. It is clear that as you increase power the machine throughput goes up faster than the total operating cost. The laser owner has an opportunity to complete more work at higher profit with a high-power laser.
Switching to percentages for the same data set, you can see that the owner of a 10kW machine gains 188% of production compared just a 19% increase in total operating cost of the 4kW system.
What if we look at cost per part?
When you put all aspects of laser power, productivity, and total operating cost you end up with a graph such as this. Power equals productivity, and also profits.
Some who see this table for the first time are very sceptical at first. That's fine, but take the time to check it out for yourself. We will be happy to help you carry out a study on your specific parts and cost structure and the result will be the same. If you have the work to fill a laser machine, then higher power will very likely deliver much higher profits.
And now back to the first statement: The laser machine market is experiencing a dynamic change. The change is an increase in laser power. Unlike many other cutting processes, fiber laser has seen, and will continue to see, gradual power increases. Of course, beam delivery, cutting head technology, and machine tool design must keep up with the power increase to ensure fiber laser maintains the reputation for reliability and low operating cost. As the pioneer of high-power laser technology and ultra-fast machine tool design, let Eagle help you analyse your production to see how power equals productivity in your shop.