Above: A robot sorts and stacks sheet parts that were laser cut
November, 2024: Numerous metal forming equipment builders across the world make amazing machines that solve problems and improve productivity, quality, performance, lead times and much more, allowing users to compete fruitfully, build new books of business and, naturally, help their customers achieve their most pressing goals.
What pushes technological developments even further is when two experts in their field combine to integrate components, creating something totally new and groundbreaking. Case in point: Arku Inc. and Trumpf Inc. together have built a complete coil-fed laser blanking system that feeds raw material at one end and comes out as part-ready blanks at the other, in a seamless way that saves time and labor and improves productivity.
“The idea is that since Trumpf is a world leader on laser cutting and we are expert at coil feeding, we wanted to to be able to cut metal directly from a coil,” says Denis Weinfurtner, North American marketing manager for Arku. “This eliminates the need for tool and die sets, and bridges the gap between that,” he says. “This is a revolutionary change.”
Creating dies for each part is costly and time consuming and constrains processing lines to only one part at a time. Space also has to be set aside for tool and die inventory. By using a complete coil-to-blank system, automotive OEMs and their Tier 1-3 suppliers— and even service centers—can adopt this technology, Weinfurtner explains. Many clients often perform all these processes, but at separate work stations.
The new streamlined process starts with Arku’s equipment: Coil loading station, decoiler, threading unit, shear, the CoilMaster precision leveler, a looping station that requires no pit, and then a unit that feeds the flat sheet into the laser blanking section.
The feed system is flexible in that users don’t have to run a full coil if it isn’t needed. The shear will cut off the needed material and rewind the rest for future use. “You can take it back off the line and put it back in inventory,” so that unused metal isn’t scrapped, Weinfurtner says.
STRESS RELIEF
Arku’s CoilMaster leveler has both upper and bottom rolls. “The bearing block sits in the front. At the bottom is the bigger backup rollers. They make sure the leveler is stable. In the middle, intermediate rollers are meant to eliminate the possibility of dirt transfer. The main rollers make contact with the material and make it completely flat for the laser,” Weinfurtner explains.
Arku can customize its leveler. “We can opt for nine to 17 hard-chromed leveling rollers, and each is individually power driven. The setup is straightforward. All you do is set the gap between the first set of rollers and the last set of rollers,” he says.
Weinfurtner calls leveling an art form.
From dead-flat coils through an integrated line jointly created by Arku Inc. and Trumpf Inc.
“Everyone wants flat sheet that’s relieved of internal stress for the most accurate cutting with no remanufacturing. As you set the gaps, you want the strip to come out dead flat at the correct thickness.” With CoilMaster, users can remove up to 99 percent of residual stress.
Arku answers customers’ questions about gauges, widths and strengths, then its engineers then specify the right leveler. “We want to know what their incoming coils look like. Do they come in with a lot of defects? It depends on what the customer is buying as to what types of defects you should expect— cross bow, torsion, coil set.
“Choosing the right size leveler is crucial,” he continues. Arku matches the material yield strength to the optimum number of rollers and the diameter of the rollers. Performance expectations for mild steel versus high-strength steel differ, for example.
The purpose of CoilMaster as part of the integrated line is to guarantee stress-relieved and flat strip before it enters the laser cutting unit. “Even when you have a coil strip that is completely flat, it may still have high internal stress so when it receives heat from the laser, the stresses pop up.” Arku wants to create strip that is “nice and tight, meeting tolerances,” Weinfurtner says.
WEIGHTS & MEASURES
SIZE RANGE
The new Arku/Trumpf coil-fed laser blanking line can take coils up to 25 tons, from 32 to 78 inches outer diameter and inner diameters of 20 to 24 inches. It will produce coil widths from 16 to 84 inches.
LOOP THE LOOP
For many standard coil operations, a looping pit is required. The faster the speed, often the deeper the pit. Digging foundations is expensive. Arku’s looping station has a stand that serves as a safe and rapid bridging of the coil strip from the leveler to the laser cutting cell. “We don’t want to stop the coil feeding; that is a no-go for surface sensitive material,” according to Weinfurtner.
The looping station runs at a slow speed to align with the speed of the laser cutting cell. “The alignment is that when the bridge is full, the laser is done and will grab the next section.” Once the laser cuts a section, more strip is pulled synchronously out of the bridge.
LASER BLANKING
James Gamache, TruLaser sales engineer for Trumpf, says the company’s system is customizable but also can be off the shelf like a 2D laser. “The unique part is the core, our TruLaser 3040,” which Trumpf has installed at customers sites all over the world.
“It is a standard machine, tied into other known systems. It contains standard components of flatbed lasers but you can process coiled material such as flat sheets,” Gamache explains. It is a more approachable answer, he says, than separate coil processing and laser blanking functions.
“It’s designed to be well integrated with other components, easy to program, easy to operate, and makes blanking more productive and flexible,” Gamache says. The TruLaser 3040 manages all standard metals along with some specialized materials. “We can define that as customers want us to.”
The standard laser unit can cut parts as small as 200 by 300 mm and up to 1,250 by 2,500 mm. “We can build it for larger parts on request.” The cutting cell is 2.5 by 4 meters, and the standard gauge range is 0.5 mm to 4 mm, “but there is also an option to go up to 8 mm. This can tackle a wide variety of materials,” says Gamache.
INTEGRATION
“We want to make systems easy to use so customers can take advantage of our technology but in the easiest way possible,” Gamache notes. Using Siemens’ WinCC, the machines talk with one another. “Other systems might be more difficult to get up and running. This system is reliable, and gives consistent cutting results,” he says.
The system is about 115 feet long, which is rather compact given the space needed by each of the functions decoiling, threading, leveling, blanking and the automated sorting and stacking of parts at the finish end. “The system could be made longer as needed, depending on the scrap solution that a customer is using,” Gamache says.
HOW IT CAME TOGETHER
Arku and Trumpf began working together in 2002. Collaboration on this new line started in late 2019/early 2020, working with Siemens as well. The line was first tested with a customer in 2022, then released to the market last year.
“We have a lot of success with this in Europe, and one installation at a steel service center in Mexico,” says Gamache.
Laser blanking has been available for years but the Arku/Trumpf line “is a new solution that targets a bit of a different market not just large OEMs and stampers, but a Tier 1 supplier, a job shop, a service center.”
All of the line is designed to be productive, creating more up time, and provide consistency, which is important for high production volumes. “You want to predict what you can manufacture in one month or one year,” Gamache says.
Users of the system can realize a 300 percent increase in productivity due to optimized material flow and automated sorting and stacking
EFFICIENCIES
Customers using the Arku/Trumpf line will be able to make parts for agricultural equipment, appliances, automotive, transportation and even everthing that job shops do. “They could be making a door for a refrigerator and manufacture those at high volume,” Gamache says, because the system can accommodate a large order book.
If a manufacturer switches from a flatbed laser to this system, he says, “they can see a 300 percent increase in productivity due to optimized material flow and automated sorting and stacking—there is no more manual operation. It’s a one-directional flow system.”
Gamache notes that coils are less expensive to source than sheets “and you can use more of the coil than you are using from sheet, resulting in a 15 percent savings in material cost and a 15 percent increase in yield from each coil. That makes the cost per part lower, which makes the business more profitable.”
Traditional coil blanking with stamping tools still offer benefits, he says, but with stamping systems, “the flexibility is limited. You must produce each part X amount of times before changing the tool or risk losing money on that tooling.”
The laser blanking system can become a universal tool because it is easy to change part numbers without retooling. Even among large suppliers, lot sizes have become smaller and the variation of parts has increased. “This addresses increased variation and smaller lot sizes but is still profitable,” says Gamache.
“Maybe we don’t eliminate the stamping press, but we can use the laser blanking as a stopgap while new tooling is being made, and with it, I can instantly retool my factory,” he says.
Service centers that operate flatbed lasers “can use this system instead,” Gamache suggests. “A service center could create a new profit center, such as performing contract manufacturing. They already have the coils. This gives them something to do with coils they are already cutting to length.”
Arku Inc., 513/985-0500, http://arku.com/
Trumpf Inc., 860/255-6000, http://trumpf.com/
