“We have always wanted technology to be a key enabler in our business so that it could leverage us into a position of strength. The benefits that are derived from using modern technology are self-explanatory. Up until now we have been skeptical about fiber laser cutting fitting into our business profile and we were uncertain whether the technology had reached a point whereby it was worth investing in it,” explained Tony Windt, Managing Director of TWR Steel Service Centre.

“In metal fabrication, no laser has penetrated the market as deeply as the CO2 gas variety. Over 25 years ago, when CO2 laser cutting was introduced, people jumped onboard because they could get better edge quality than they could with plasma and profile cutting. With laser you have a near finished product and the component can then be put into fabrication without additional preparation. The high accuracy and clean cutting finish achieved by a laser is a more expensive process. However, not all components need the accuracy of a laser-cut. In this case either plasma or oxyfuel can be used as they are lower-cost processes.”

The new Bystronic BySprint 6kW Fiber 4020 laser cutter

“When we established TWR Steel in March 2012 CO2 laser cutting was a proven technology. At the time fiber laser cutting was a relatively new fabricating technology, having debuted on the global stage at the 2008 EuroBLECH event in Hannover, Germany.”

“As a result we purchased a Bystronic 6 kilowatt machine that has a bed size of 6.5 x 2.5 metres and a Bystronic 4.4 kilowatt machine with a bed size 4 x 2 metres. We have been cutting steel plates in thicknesses of up to 25mm, material dependent. The majority of the material that we cut is carbon steel across all our processes – we also have a Messer high definition plasma cutter and an oxy-fuel cutter – but in recent years stainless steel and aluminium demand has been on the increase.”

“The CO2 laser was the industry workhorse for a reason: It’s inexpensive compared to other legacy technologies like Nd:YAG laser cutting and it offered a beam quality suited for cutting and welding metal. But it does have drawbacks. The CO2 laser requires a hefty supply of lasing gas. To get the beam from the resonator to the metal takes careful alignment and maintenance of mirrors. And when it comes to power consumption, they aren’t the most efficient systems. They draw a lot of power and produce extremely hot gas that requires cooling. That’s basically why the CO2 laser’s wall plug efficiency – or the optical power from electricity consumed – is only 10 to 12 per cent.”

The new Bystronic BySprint 6kW Fiber 4020 laser cutter now allows TWR Steel to cut light gauge material at a fraction of the time it used to take on it’s CO2 laser

“Our business was built on cutting thicker plate and it will continue to play a significant role, both in tonnage processed and turnover. However, we started to get more demand for cutting thinner gauge and we also needed more capacity. Eventually the CO2 lasers could not keep up with demand needed on light gauge sheet metal, and its economic efficiency was limited to thick metal work. We needed another choice and this is when we started to look at the fiber laser, especially as the process had now advanced dramatically technologically.”

“The fiber excels at cutting light gauge material, but for thick plate, not so much – at least that was the common story. But just within the past few years, the story has changed, just as I did. I hate to admit it but I did not have any faith in fiber laser cutting when the technology was first introduced.”

“But now when the fiber laser – so called because the laser is created by diodes that are fed into fiber optic cables where the excitation process takes place and is then delivered to the cutting head by another fiber optic cable similar to one used for data transfer – gets going with cutting thin gauges, it needs to be constantly fed with material. And we now have clients that require production runs of thin gauge components.”

“Then there’s the speed advantage. Roughly speaking, because there are many variables to take into account, on 1mm gauge our new fiber can cut five times as fast and on 5mm three times as fast as compared to our CO2 lasers. That’s an increase of 500% and 300% respectively on the cutting speeds. At the upper level of a fiber laser’s thickness range though – a gap that is reducing now – the speed difference does change in favour of the CO2 lasers. That cutting speed disparity is reduced when the fiber laser is programmed to cut thicker material. As the materials get thicker, the speed advantage goes away as power becomes more important in the equation.”

TWR Steel have also purchased a Bystronic ByTrans Extended for loading and unloading the laser cutting system

“Fiber laser cutting systems can be easily spotted by the tinted glass, designed so that operators can gaze safely at the work and be protected from the invisible scattered or diffuse reflected laser beam on the other side. And though the machines do not use lasing gas, they do use common assist gases, such as oxygen, nitrogen, argon, and compressed air.”

New Bystronic BySprint 6kW Fiber 4020 laser cutter
“We decided on the Bystronic BySprint Fiber 4020 machine with a Fiber 6000 laser source because the higher power considerably increases the BySprint Fiber’s cutting speed in the thin to medium range sheet metal thickness. For example, a 6kW fiber laser cuts 3mm stainless steel up to 70% faster than a 4kW fiber laser. Its speed advantage is even more pronounced when compared to cutting the same material with a 6 kW CO2 laser source where the 6 kW Fiber laser is three times faster. Bystronic has equipped the 6kW version of the BySprint Fiber with Cut Control to monitor the cutting process. When a cutting tear occurs, Cut Control automatically stops the laser and the cut is repeated. This reduces the risk of miscuts.”

Bystronic ByTrans 4020 Extended
To prepare for the fiber laser’s arrival TWR Steel rearranged the entire area where laser cutting was taking place. It did this because it still intends to keep its two Bystronic CO2 lasers productive and more importantly it had to accommodate a Bystronic ByTrans 4020 Extended.

TWR Steel have also purchased a Bystronic Xpert 80 press brake

“The ByTrans Extended takes over loading and unloading of your laser cutting system. The ByTrans Extended design has not just one but two cassettes, thereby making the machine system even more autonomous.”

“With the BySprint 6kW Fiber 4020 laser cutting as fast as it does it made no sense not to include a ByTrans Extended.”

“We followed the keep-it-simple policy, and we bought a relatively simple loader/unloader rather than a more complicated part-sorter style. You can kill yourself with technology if you go too far.”

“The fiber laser hasn’t stopped running since its implementation. It is actually pushing downstream activities to operate at a faster pace.”

Bystronic Xpert 80 press brake
To respond to the need for additional bending capacity TWR Steel have also purchased a Bystronic Xpert 80 press brake.

“Continuing the concept of the mobile press brake, with the smaller version Xpert 40, already established in the market, Bystronic recently launched the Xpert 80, which offers a decisive increase in bending length and press capacity and as a result opens up a wide spectrum of applications. In a footprint of less than 3m², it offers a bending capacity of 80 tons over 1.5 metres.”

“The new, larger press brake can bend material up to 20mm thick and is suitable for almost any task, from large volume runs to small batch and job shop production of complex parts. The machine may be equipped with multiple tools to enable all bends to be completed sequentially. ByMotion drive control, a Bystronic development, ensures that the Xpert 80’s upper beam and backgauges are accelerated with high precision. Fast bending speeds up to 25mm/s are attained.”

Sensible investments
“We are confident that the investment in the new fiber laser cutting capacity will pay off. The machine is operating as promised, and the company’s preparation has paid off, too, in that there were no major hiccups during installation and early operation. Looking down the road, the machine will require less maintenance as it doesn’t have the moving parts or mirrors found in its CO2 equivalent.”

“The lack of surprises has helped us keep up with work and maintain a solid cash flow position. That feeds the ability to invest in new equipment when it’s needed to respond to changing customer demands or market developments.”

“It’s part of the plan. You can’t stay relevant if you don’t have the latest equipment, and you can’t buy the latest equipment if you aren’t growing.”

For further details contact TWR Steel on TE: 011 578 8880 or visit www.twrsteel.co.za