Metal fabricators worldwide share one major goal: Streamline the production process
December 3, 2012
A terrible economy has forced European metal fabricators to focus on shortening turnaround time on jobs. If they attended EuroBLECH 2012 in Hannover, Germany, in late October, those fabricators probably discovered some tools that could help them accomplish their goals.
Leading indices indicate that manufacturing output has declined for almost a year. Certain geographic areas are suffering greatly from very high unemployment rates. Local governments are unable to inject stimulus funds because of skyrocketing debt. Does this sound like the depths of the Great Recession in the U.S. circa 2008? It might, but this actually is the state of the countries in Europe. Bad times are back again.
As of mid-October, the overall PMI for Europe was 45.8, marking eight consecutive months of a below-50 reading. (An index score below 50 indicates that manufacturing is contracting; a score above 50 suggests that manufacturing is expanding.) Considering that the two most vibrant manufacturing economies in Europe, France and Germany, have experienced at least six months of decline as well, an economic rebound is not going to occur anytime soon.
Additionally, the European Union is still trying to figure out what to do with the financial disaster that is Greece while hoping situations in Spain and Italy don’t get worse. Austerity budgets seem to be the only feasible medicine to remedy the fiscal crises, but they don’t do much for propping up weak economies in the short term.
So what does this mean for metal fabricators in Europe? It’s time to start finding efficiencies and taking a hard look at the entire metal fabricating process—the time between receipt of the order and shipping the product out. Eliminate as much waste in that process, and you maximize cash on hand.
In a way, metal fabricators in North America and Europe have more in common than ever as they have survived the Great Recession or are currently surviving another economic battering. They both seek out automation. They both want to maximize floor space. They both want to eliminate waste where possible.
EuroBLECH 2012, Oct. 23-27, held in Hannover, Germany, was the perfect event to showcase this trend. The sheet metal technology tradeshow attracted 60,000 visitors and 1,520 exhibitors from 39 countries. The show itself took up 904,000 square feet. At every turn, a metal fabricator could find something to help it shorten its turnaround time.
It’s been three EuroBLECH shows, or almost six years, since fiber lasers made their big debut in the metal fabricating industry (see Figure 1). These solid-state lasers, which rely on semiconductor diodes to pump special optical fibers doped with rare-earth ions for beam production, continue to capture market share. It’s been a learning experience for many.
Ferdi Töngi, CEO, Bystronic Inc., a metal fabricating equipment manufacturer, once believed that fiber lasers had their place and eventually would grab as much as 25 percent of the market. Today he has adjusted that to about 50 percent of the market.
“How fast it grows nobody really knows. But it grows much faster than we thought at the last Euro– BLECH,” he said at a press conference.
In a way, fiber lasers have democratized machine tool development (see Figure 2). As Töngi said, “Every two weeks we get a new competitor.”
LVD debuted its fiber laser at EuroBLECH this year. Its Electra FL series is designed to cut thin-gauge sheet metal at speeds up to 50 percent faster than traditional CO2 lasers.
The technology’s short-wavelength, high-beam-quality laser delivered via a fiber has always enjoyed a speed advantage over the traditional CO2 beam, which has to rely on mirroring systems to deliver the laser beam to the cutting surface. However, the mechanics of a machine now are designed specifically to cater to the cutting speed of the fiber lasers.
Because a fiber laser doesn’t require a large resonator cavity or a large chiller, it comes in a small package, which makes it a prime candidate for integration into more traditional machine tools. For instance, Amada incorporated a 2-kW fiber into its LASBEND AJ machine (see Figure 3), which has a vertical laser cutting setup, a swinging press for bending, and a forming and tapping station in one device. This type of device is obviously designed for specific jobs (think small electronics applications), but it still fits into a footprint that is about the size of a small CO2 laser.
Today’s machine offerings are also helping to dispel the belief that fabricators want these machines only for thin-gauge cutting of sheet metal. For example, Messer Cutting Systems introduced its own fiber laser cutting machine that can make not only vertical cuts, but also beveled cuts for optimal weld seam preparations. Fabricators aren’t afraid to look at fiber lasers as general metal fabricating tools.
“The fiber is now delivering a cut on 0.5-in. material that is hard to tell the difference when compared to the same piece cut on a CO2,” said Jason Hillenbrand, laser product manager, Amada America.
So the fiber laser’s speed and versatility help it to produce more parts more efficiently, but might that just create a bottleneck at the press brakes if a fabricator is unable to absorb the extra work? That could be the case, but press brake manufacturers are addressing that as well.
LVD introduced its ToolCell press brake system (see Figure 4), which has an integrated tool changer unit, at EuroBLECH. The tool library is found in the dead space commonly found where the backgauges do their work. Actually, those backgauges, with grippers built into the fingers, are the mechanisms that place and remove the press brake tooling. There is no robot.
Matthew Fowles, LVD’s group marketing manager, said this automated tooling storage, retrieval, placement, and removal system is designed to help metal fabricators contend with reduced batch sizes and shortened lead-times. The operator can focus on selecting and loading the blank onto the press brake, while the press brake changes the top and bottom tooling for the upcoming job.
The press brakes also feature the company’s Easy-Form® laser that measures the angle during bending and can adjust the ram to ensure the part is made right each time. A laser at the front and back of the die determines the exact value of the angle, and sensors transmit the information to the CNC unit. The control processes the measurements and subsequently recalculates the correct depth adjustment to obtain the specified angle. This occurs while the bend is taking place.
“The old-school guys—the ones who know what happens to the metal—are leaving,” Fowles said. “The new ones know computers, but do they really know about things like a neutral axis and metal strain?”
Other machine toolmakers have introduced their own press brake tool management systems (see Figure 5). For all of them, the goal remains the same: Reduce downtime and increase throughput.
Automated placement and removal of press brake tooling is one way to help achieve more uptime. What if there were a way for the operator to focus constantly on the job without having to refer back to a computer screen over his shoulder?
SafanDarley demonstrated its Eye augmented reality glasses during the tradeshow (see Figure 6). These glasses allow the press brake operator to see the tooling setup, bending sequence, and work instructions right in front of him while also looking at the actual tooling and workpiece. With the glasses on, the operator is seeing what normally shows only on the computer screen, eliminating the need to break away from the bending process to double-check his work.
Admittedly, the technology won’t be adopted overnight, but it may appeal to younger workers who are already accustomed to wearing gaming goggles or 3-D glasses, according to SafanDarley management. The company is already thinking ahead about future features, such as activation of virtual buttons so the operator has one fewer reason to go back to the control.
Fabricating shops obviously do more than laser-cut and bend metal. Consequently, technological advances aren’t limited to only those areas.
For the past several years, servomotors have created a buzz in the metal stamping world. The advanced motor technology allowed mechanical presses to mimic the motion profiles of hydraulic presses, such as dwelling several seconds during the final moments when the ram is in full contact with the die bed.
Schuler, a German press builder, has rethought the servo press concept and debuted its TwinServo Technology at EuroBLECH. The new design calls for two decentralized servomotors in the press bed, not on top of the press as with traditional machine designs. Because of that, the new press is a little less than 20 feet shorter than Schuler’s other servo presses.
A compact design is one thing, but the new approach also helps out the metal stamper looking to speed up die changeover. The footprint is smaller, and moving bolsters can be placed closer to the machine for die changes. Because the new press doesn’t have uprights, access to the die area is improved. In this case, four draw rods handle the slide movement, which has the added benefit of allowing the press force to be extended to the end faces of the slide. As a result, the press can handle greater eccentric loads than traditional presses, and the maximum press force can be used right up to the bed edge for forming operations.
Company management also reported that the new press design reduces blanking shock and helps to resist tilting during material feeding.
Probably one of the most interesting welding developments isn’t brand-new, but it still holds great promise as more manufacturers learn about it. The German welding company EWM highlighted its forceArc® spray arc welding technology. With its short and powerful arcs, the welding process is able to lay down plenty of metal in fewer passes and at great penetration depth. Company management said the welding technology is able to complete a butt weld with a 30- or 40-degree opening angle in only five passes; it might take more traditional standard spray 11 passes and a 60-degree opening.
In a fillet weld, the welding process is designed to deliver deep fusion, which can lead to a reduction in the throat thickness or the weld cross section. The process controls help to stabilize the arc even when stickout lengths of the welding wire change. The controls maintain the stable arc even with long stickout up to 1.5 in.
For one application involving welding on an oil platform in the North Atlantic, an EWM press representative described how the forceArc process reduced a 150-hour, 150-pass welding job to a 50-hour, 40-pass exercise. The welder also didn’t have to worry about making any root passes.
From the middle of the Atlantic Ocean and all points east and west, metal fabricators need tools to help them produce metal parts more efficiently. They may speak different languages and eat different foods, but the world’s metal manufacturers (see Figure 7) all have that one goal in common.