Cutting technologies are continuously evolving, and one of the most significant recent advances in the field is fiber laser. Fiber laser technology has been available for only about three to five years; so many companies are still getting acquainted with it, and are just beginning to appreciate the differences between fiber and the more ‘traditional’ CO2 laser.

Of the key thermal cutting methods involving oxyfuel, plasma, and laser technologies, laser cutting offers the best cut quality, especially for fine features and holes that have less than a 1:1 diameter-to-thickness ratio. This makes laser the most appropriate method for stringent precision cutting needs in any industry.

And within the laser cutting category, fiber laser is garnering a lot of attention because it offers the speed and cut quality of CO2 laser, but costs significantly less to maintain and operate. This makes fiber laser so promising as a cutting technology that many experts believe it will soon overtake other laser systems.

Key advantages of fiber cutting

In CO2 laser, CO2 gas is involved in the transmission of the beam. In fiber laser, however, transmission works through diodes and fiber cables. Instead of relying on mirrors to transfer the light beam, fiber laser systems rely on multiple solid state pump diodes to generate a laser beam, which is then transmitted through a flexible fiber cable to the laser cutting head. This offers a number of benefits, the first being table size.

Unlike gas lasers, where mirrors must be a set distance apart, there is no size restriction for fiber laser. It is even possible to install a fiber laser cone right next to a plasma cutting head on a plasma cutting table, which wouldnÕt be an option for CO2 laser. Also, the ability to bend or coil fiber means that the systems are relatively compact when compared with gas systems of comparable power.

But perhaps the most important and significant benefit of fiber laser is its energy efficiency. Because of fiber laser’s completely solid state digital, monolithic design, fiber lasers have higher wall-plug efficiency than CO2 laser. For every unit of power that passes through a CO2 cutting system, it’s common that about eight to 10 percent is actually used.

Whereas for fiber laser, users can expect much higher power efficiency figures of between 25 to 30 percent. In other words, a fiber system consumes about 3 to 5 times less energy overall than CO2 versions, making it up to 86% more energy efficient.

Fiber lasers also feature positive light properties such as a shorter wavelength, which improves beam absorption into the material being cut, and enables the cutting of non-conductive metals such as brass and copper. A more concentrated light source creates a smaller spot and longer depth of focus so fiber laser can cut thin materials fast and medium thickness materials more efficiently. Up to 6mm (1/4), a 1.5kW fiber laser has cut speed equivalent to a 3kW CO2 laser.

This translates to increased output, yet with lower business costs because the operating costs for fiber cutting are lower than that of traditional CO2 systems.

There’s also the issue of maintenance. Traditional gas laser systems require regular maintenance; mirrors need to be maintained and calibrated, and resonators need to be replaced. Fiber laser solutions on the other hand hardly require any maintenance, if any at all. CO2 laser cutting systems require CO2 lasing gas, which can collect impurities that need to be cleaned out regularly.

This can cost at least US$20,000 annually for a multi-kilowatt CO2 laser system. In addition, many CO2 cutting formats use high-velocity turbines to move around the lasing gas, and these turbines will require maintenance and eventual overhauling. And lastly, because fiber solutions are more compact and have a smaller footprint compared to CO2 systems, there are less cooling requirements, and energy consumption is significantly reduced.

The combination of low maintenance and higher energy efficiency translates to the fact that fiber laser has a smaller carbon footprint, and is therefore more eco-friendly than CO2 laser cutting.

What to consider when adopting fiber laser

There are a few important things to take into account when adopting fiber laser. Eye safety is the first. The light from a fiber laser system is at a wavelength that is hazardous to the eye, so good eye protection is a must. Comprehensive training for proper system operation and safety is highly recommended as well, since the technology has only been around for five years or less. Many operators do not have much experience cutting with fiber, so this lack of experience needs to be filled by some good initial training in controlling fiber cutting systems.

Another consideration is the material to be cut. While fiber laser is excellent at cutting most materials, it cannot be used to cut acrylic or polycarbonate, and can only cut wood or fabric in limited applications. Also, the thickness of material to be cut is an important factor in deciding when to use fiber laser. Thicker materials will require more power to cut, and in those instances, laser cutting may be less attractive of an option. This is where the ability to install fiber laser right next to a plasma cutting head may be well utilised. Operators can cut thinner material requiring tight tolerances with fiber laser, before quickly and easily switching to plasma. It is even possible to cut the same part with two different cutting methods. For example, an operator can choose to cut the outside of a part with plasma, and then any inside shapes with fiber laser.

One good final consideration is to assess which components are necessary for a comprehensive laser cutting set-up, and how to acquire each part. A system that comes complete with the laser power source, gas console, laser cutting head and height control, the computer-numeric control (CNC) and cutting control programmes will offer the valuable benefit of an all-in-one off-the-shelf solution. With a comprehensive solution, the process of purchasing and integrating the fiber laser is much less complicated. Consider shortlisting a system that was optimised specifically for cutting, where cut parameters were identified in advance so that cutting can begin as soon as power is supplied.

Conclusion

In summary, fiber laser offers many unique benefits over the traditional CO2 laser cutting systems such as higher energy efficiency, lower maintenance costs, and a more compact solution – but it may not be right for everybody. It is important to consider safety and training, the type and thickness of material most often cut, as well as the cut quality needed, before choosing a comprehensive laser solution.

Yet as much as laser cutting is able to offer multiple benefits to companies today, it is still a relatively new technology that is rapidly evolving. This only means that laser will likely see continued improvements to meet its true potential in the years to come, so companies can look forward to cutting even faster and better with the fiber laser technology of tomorrow.

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