Not only are fiber lasers for cutting applications dominating the market, their quality is improving. Increased laser power, speed, and capability are enabling new applications.
Implementing a comprehensive laser cutting system is not a task for the faint of heart. In addition to the financial outlay, requirements include planning for a complete system, not just the laser, according to Dustin Diehl, laser division product manager, Amada America Inc., Buena Park, Calif. There is also siting the installation and acquiring the laser unit and equipment, including loaders, unloaders, chillers, and controls. Finally, the system needs to be integrated into overall reporting and feedback loops. The result is a system capable of generating a substantial ROI in a surprisingly short time.
Although CO2 lasers, which represented the formative phase of laser cutting, have been eclipsed by the newer fiber lasers, they still have a place in the market. Jeff Tyl, North American sales manager-fabrication at Murata Machinery USA Inc., Charlotte, N.C., explained, “modern CO2 lasers are typically used for cutting stock over 1″ and can deliver a clean cut. Also, they’re not limited by table size. They are still an important factor in critical industries like shipbuilding and defense, but the fiber laser is clearly the most popular choice for conventional sheet metal applications.”
While most fiber lasers sold today are in the 1 to 6 kW range, higher powered configurations are making inroads in select applications and will continue to grow in market presence. Brendon DiVincenzo, product manager for lasers and automation at Bystronic Inc., Elgin, Illinois, commented, “steel service centers have welcomed the advent of higher powered units that currently have an operating capability in the 10 to 12 kW range. As speeds increase, we will see greater demand.”
Today’s fiber lasers are typically part of a complete processing system, as noted by Amada’s Diehl. “The laser can’t be considered as a standalone unit. It’s got to be part of a system,” he said. “We work with our customers to ‘do the homework’ going in so as to deliver a package in which all the modules—loading, unloading, and the unit itself—are engineered together. Power is a part of the equation, but depending on the application, the entire system has to be considered.”
Fiber lasers need to be versatile as well, capable of processing different types of material. For example, Amada’s ENSIS Series uses proprietary fiber laser technology to process both thin and thick materials without a cutting lens change or manual setup. The 3 kW fiber engine incorporates Amada’s ENSIS technology, which optimizes the laser mode and beam parameter product (BPP) based on the material thickness being processed. The ENSIS Series is capable of high-speed cutting in thin material, a key capability of fiber technology, and can process thick plate efficiently, according to Amada America.
Improvements in cutting technology are a significant factor in the growing popularity of fiber lasers. “The early fiber units had problems with leaving ragged edges,” said Mark Bronski, head of sales for lasers at Trumpf Inc. in Farmington, Conn. “The additional power and refinements have resulted in the ability to achieve a finish comparable to CO2 in 5/8 to 3/4″ [15.9-19.05-mm] plate.”
Hank White, software systems manager at MC Machinery Systems Inc. in Elk Grove Village, Illinois, noted that customers are selective when it comes to laser power. “Although we’re seeing growth in the market for 8 kW systems, customers are exceptionally careful in determining power requirements for their individual application. If lower powered units can do the job, they will stay with that category because larger units cost more to purchase and run, and in many cases, can’t go faster.”
Higher powered laser cutting is making some significant inroads in more specialized areas. These include 3D applications, holemaking, and coil and tube processing. Mark Barry, vice president of sales and marketing at Prima Power Laserdyne LLC, Champlin, Minn., commented, “in two-dimensional cutting, the industry is seeing increased demand for 6 kW, but when it comes to high precision in applications such as drilling cooling holes in turbine engines, higher power QCW (Quasi Continuous Wave) lasers deliver the required level of precision.”
Robert Adelman, North American laser product manager at BLM Group USA, Novi, Mich., noted that, in tube cutting applications, power requirements have moved upward from 3 kW to 5 kW. “Fiber lasers all pierce faster and cut faster, although we don’t use the output powers typical in the flat sheet world as there is always the other side of the tube to consider,” he said. “This is true on both conventional 2D machines and 3D units up to 45°. Depending on the machine, diameters range from 1/2 to 24″ [12.7-610 mm] OD, and larger machines can drill and tap as well.”
LaserCoil Technologies LLC, of Napoleon, Ohio, purchases lasers to integrate into coil blanking operations. Jay Finn, GM and CTO, stated, “we move up in power when we’re comfortable with the optics. We currently use an 8 kW laser for systems that process material from 0.5 to 35 mm while producing the desired edge. Most of our systems feature multiple heads and include complete material handling systems.”
Automation Combined with Lasers
With fiber lasers, automation is a fact of life. It is possible for a small shop to start with a simple loading system. Before long, however, the realization strikes that more components are needed to achieve its full potential. It then becomes obvious that a good deal of planning and commitment is required.
One of the prime considerations involves space. Lasers need a dedicated area reasonably free of contaminants and large enough to provide for any addition of further automaton equipment. Amada’s Diehl noted that it is wise to “estimate dollars per square foot. Before going in, become familiar with the various modular systems so as to understand how the installation will progress. We rarely sell standalone lasers. The systems we provide are geared to both expansion and flexibility. Given the speeds of production, the primary challenge is the management of the stream of parts coming off the machine.”
DiVincenzo from Bystronic agreed. “Automation is a significant factor for both large OEMs and small shops, even though they differ in process needs,” he said. “For instance, a steel service center is primarily concerned with quantity, in terms of ‘tons across the laser bed,’ whereas a job shop is looking for velocity and efficient material flow.” The variety of components has made it possible for users to develop individual automation strategies to suit them.
Tyl of Murata Machinery noted, “we sell three varieties of systems, broadly speaking. The pallet loader, a tower with four or eight drawers, and a parts sorter system. The tower supplies the stock, and the parts sorter system advances cut parts onto the next station. Moving into the future, we see hybrid lasers with multiple functions gaining in popularity.” Small shops might be constrained by costs. “Shops using various materials can get into the game by programming a single pallet loader,” Tyl said. “As their business increases, automation becomes irresistible thanks to the fast ROI.”
As cutting automation drives increased production, further automation is necessary. “Downstream processing is the next frontier, including edge cleaning and forming,” stated White from MC Machinery Systems. Key to the success is the development of software that can pull modules from different manufacturers together through a unified program.”
The many different shapes and configurations of tubing need a more specialized approach. “Conventionally, machines were not capable of bundle loading custom shapes in tube lasers,” explained Adelman of BLM Group USA. “Today, tube lasers can bundle-load a special shape like ‘peanut’ automatically. Using specialized cameras, the machine can detect the orientation of the tube to ensure proper clamping, as well as proper part orientation.”
“Flexibility is key in coil processing,” explained Laser-Coil’s Finn. “Every system we sell operates in continuous and index modes and can interface with any type of stacking. Also, we’ve designed our modules to feature the same footprint as older mechanical blanking equipment to ease the updating process.”
Barry from Prima Power Laserdyne summed it up: “If you’re going to have laser cutting, you’re going to have automation. The laser is not a discrete item, it’s a component.”
Controls, Automation and Operators
Supporting the drive toward automated laser cutting systems are a variety of sophisticated controls that must be integrated. “The ideal control paradigm involves a seamless integration to ERP systems, thereby eliminating waste in the administrative processes. Crucial to success is total constant monitoring, as well as maintenance alerts. The goal is zero unplanned downtime,” stated Trumpf’s Bronski.
Modern automation systems have greatly enhanced the status of the operator. This is especially visible in the evolution of controls in integrated systems. Diehl from Amada America commented, “Twenty years ago, a laser system control was as complex as an airplane cockpit. Now, it’s more like an iPad, offering touchscreen interface and better graphics. The systems have a better editing function and vastly improved feedback. The operator can remotely monitor service issues, service history, and alarm status for past or current alarms.”
Bystronic’s DiVincenzo noted increased customer demand for standardized controls. “Customers are demanding compatible controls that can interface not just with the laser cutting system but with other machines and ERP systems, processing work orders and funneling data and parts to the next operation.” White agreed and noted: “When it comes to the processor, different builders all have their own ‘secret sauce.’ Nonetheless, standardization is coming, but with it, security is critical.”
Controls and software have made a huge difference in coil processing. Software systems can calculate a nest based on the optimum cutting pattern for a particular coil width, as well as determining the coil width that will offer the best yield. Finn explained, “The final nest is dependent on the coil feeding process. The leading edge must match the ending edge. To ease adoption, we have developed software to automate nesting and cutting path optimization. This makes it less intimidating when bringing lasers into your operation.”
Control and software systems have also created extensive advances in manipulating the laser. “There has been a huge improvement in changeover time for both conventional and complex parts. We can now change power on a pulse-by-pulse basis with a response time literally be-yond milliseconds,” said Barry from Prima Power Laserdyne. “This has enabled us to acquire immense flexibility in multi-purpose operations. For instance, we are able to not only produce any shape of hole at any angle but move from drilling to welding. By adjusting the power and pulsation, we’re also able to handle new materials including carbon matrix composite (CMC).”
Controls have likewise advanced flexibility in processing tubular materials. “The latest integrated systems take the work off the machine and have moved it to the production planning stage,” said Adelman of BLM Group USA.“ Now, nesting software can not only nest parts into jobs but also select which options are necessary (like weld seam orientation on tubes) to create an entire production run, while a novice operator can focus on managing material loading and part packing. The control functions can create production schedules and calculate accurate job times and cost. To ensure our customers are able to benefit from the many control capabilities, we provide training at both our facility and our customers’ sites.”
Quality Improvements in Fiber Lasers
Thanks to the combination of power and control features, today’s fiber lasers have moved up the curve, insofar as quality is concerned. To some extent, this is due to user experience and control capability in defining the correct parameters for specific material types. “Flow technology, improvements in the use of diodes and optics, and greater care in defining the mixture of gases have all contributed,” according to MC Machinery Systems’ White. “Even with the improvements at the laser head, the cost equation is still present, and some users feel that it’s more economical to employ a subsequent finishing process than to spend the effort in regulating the laser.”
Two of the most important factors in quality control are preventative maintenance and material management, according to Bronski from Trumpf. “The complexity of laser systems demands a high degree of preventative maintenance, and training is absolutely essential. Another key factor has to do with the material involved in the process. Users have to inspect what they get to ensure high quality or they’re going to lose out on performance.”
Amada America’s Diehl cited the importance of gas mixing. “Using the proper mixture of gases can improve edge quality to the extent of eliminating secondary operations. We’re seeing the increasing popularity of in-house nitrogen generation using filtration, booster pumps, and storage tanks. There’s also a trend to part inspection through 3D imaging and vision systems.”
The balance of speed against quality remains a primary consideration. As systems have advanced, efforts to maintain quality at high speed have included the use of high-precision linear drives as opposed to rack and pinion, and the incorporation of servo motors. Real-time inspection is key in tube and coil operations. Scanning can now detect twists in tubular stock and adjust to compensate. Likewise, coil stock can be inspected “on the fly” to ensure proper quality control. DiVincenzo from Bystronic summed up the economics of quality: “It’s no longer about the cost of labor but the speed of labor.”
As improvements in laser cutting and automation technology progress, fabricators and other end users will be faced with a variety of choices that will impact not only the cutting operation but, in the case of OEMs, the entire manufacturing process. The speed of the laser and the advent of more extensive automation may well do for fabrication what the assembly line did for automotive production.
The End User Experience: Hatco Corp.
Headquartered in Milwaukee with manufacturing facilities in Sturgeon Bay, Wis., Hatco Corp. is a manufacturer of commercial foodservice equipment. It makes foodwarmers, food merchandisers, toasters, and other products. Production lots range from hundreds of units for placement in convenience or fast-food restaurants to a single specially featured warmer for a particular facility. The company’s mantra is “An economical order quantity of one.”
In pursuit of that goal, the company has continually enlarged and updated its manufacturing facility with the latest in equipment and techniques.
According to Steve Christoferson, Hatco vice president of manufacturing, “many manufacturers and shops tend to be ‘part centric’ and see the individual parts as ends in themselves. At Hatco, our processes are product driven and, because our people can see the entire process under one roof, there is a constant awareness of maintaining tight inventory controls and efficient manufacturing flow.”
Hatco’s experience with lasers goes back far enough that Christoferson recalls “the slow speed of the early lasers was painful to watch. Now, thanks to speed and quality, fiber is the future.”
At present, Hatco uses four Mitsubishi lasers, three of which are CO2 and the latest a 4 Kw fiber laser. The metal processed includes over 100 different sizes and gauges, from plate to 24 and 28” gauge and includes stainless and mild steel as well as aluminum. Tolerances can be as tight as 0.0001” (2.54 µm). “Because so many of the parts that we manufacture are three dimensional, we literally have to take the part and ‘unfold it’ to achieve the correct cutting pattern. We use dynamic nesting to optimize yields from the raw materials,” Christoferson commented.
The lasers are located in a dedicated section of the plant. A Mitsubishi “River” FMS moves material in and out. “It took a full year’s work to move to the automated system that we wanted,” said Christoferson. “We opted for a 4 kW fiber system as the most economical for our purposes. Work is assigned to each of the four lasers based on the type and thickness of the material and the quality of the cut that can be achieved.” The laser area was designed to allow for future expansion and is located adjacent to downstream processes for deburring (when necessary) and bending.
When it comes to quality, Christoferson noted that “every operator is an inspector.” Hatco employees are trained in multiple manufacturing disciplines so as to understand the complexities of the process and to be able to intervene in the event that any problems are spotted. Several years ago, the company was purchased by the employees, and there is a “proprietary interest” on the part of everyone.
Dave Rolston, Hatco president, was formerly head of engineering and can frequently be seen on the manufacturing floor. “We’re exceptionally proud of the quality of our equipment and the extent of automation that we have achieved in our laser area,” Rolston commented. “But, in the end, it is the skill and pride of our people that keeps us ‘best in class.’”