Advanced Bending Delivers Digital Displays

December 1, 2018

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Manufacturing Resources International (MRI), in Alpharetta, GA, is among a vanishing breed of OEMs that do not subcontract anything. Not a thing. “Instead, we’re a totally vertically integrated company,” says founder and CEO Bill Dunn. MRI (www.mri-inc.net) designs, engineers and fabricates BoldVu high-performance outdoor digital displays found in and around urban settings such as bus shelters, shopping centers and school campuses and sold under the LG brand as a result of a 2014 joint-venture agreement with the electronics giant. The displays rely greatly on advanced fabricating equipment, notably the Multibend Center by RAS Systems, LLC in Peachtree City, GA.

An MRI display in a San Francisco bus shelter. MRI’s BoldVu displays are ubiquitous in the urban landscape. Media advertising generates revenue used to offset the cost of maintaining street furniture fixtures, such as bus shelters.

But the MRI story really begins nearly three decades and a couple of companies ago, when Dunn, an electrical engineer, after spending 13 years developing displays for defense contractor Loral Corp., formed Avionic Displays Corp. (ADC) in 1991. “We brought full-color, active-matrix, LED technology to the cockpits of military aircraft for the first time,” says Dunn, whose success with ADC led him to form American Panel Corp. (APC), said to be the largest design and manufacturing center for aircraft displays, both commercial and military. “APC displays are on every Boeing, a lot of Airbus planes and 70 percent of the free world’s military aircraft.” Though ADC no longer exists, Dunn continues as owner of APC while overseeing the growth of MRI.

“We have about 40,000 large-format outdoor displays worldwide,” he says, “and we’re producing nearly 8000/yr.”

Inside MRI

Designed to be configurable with modular on/off-loading options, the Multibend enables a manufacturing facility to start with a manual configuration and later integrate robotic handling as volume and budgets allow.

MRI resources are extensive, with the company housed in two buildings, the first being 28,000 sq. ft. and the second accounting for 137,000 sq. ft. MRI’s second building is undergoing an 80,000-sq.-ft. expansion. When completed by the end of Q1 2019, MRI will total nearly 245,000 sq. ft. of space for its 200-plus employees, one-third of which are degreed engineers involved with design, production and process engineering. APC occupies an additional 48,000-sq.-ft. facility for a staff of 100-plus, with approximately one-third of those being degreed engineers as well.

“We’re doing it all—the design, analysis, simulation, production, and testing and product support,” says Dunn. Packing, too, with MRI’s original 28,000-sq.-ft. facility now used for fabricating the crates used for the 750- to 1500-lb. products transported by tractor trailers or shipped via ocean containers.

“Totally vertically integrated,” Dunn repeats.

MRI’s inventory of equipment is, in a word, extensive, as is its materials usage. The new addition on the main MRI facility will include an automated powdercoat line; glass-tempering, heat-strengthening and annealing capability; high-speed digital frit printing on glass; aluminum-extrusion and 3D-bending capability; two fully robotic/ automatic, four-bowl hardware insertion machines; and one robotic cell for post-weld grind/deburr, knockout removal and blank shearing.

Existing equipment includes a jumbo glass-fabrication line with an autoloader system, glass scribe and break, five-axis glass CNC machine, double-sided glass-washer/scrubber equipment, 1440-dpi digital-ink glass printer and curing ovens; and a fully automated PCB assembly for surface-mount and through-hole components with capacity to build approximately 400,000 circuit boards/yr.—each having about 1000 electrical components. This PCB assembly line also includes conformal-coating capabilities.

And then there’s MRI’s sheetmetal-fabrication operations:

Two (each building) 6-kW fiber lasers with material handling;
One dual-head CNC waterjet cutter with pneumatic drills;
One 250-W CO₂ laser;
Four press brakes with hemming tables and dynamic crown correction;
Two automated panel benders;
Six multi-bowl manual hardware-insertion machines;
One (each building) 10-ft., 10-gauge shear (robot or manual load);
One 60-in. sheetmetal deburr sander;
Two 12-in. and one 48-in. vibratory deburring machines;
Two robotic welders, each with dual rotisseries and Lazy Susan stations;
One five-axis, CNC extrusion profiler; and
One RAS Multibend-Center 79.31-2 with dual-station automatic gantry loader and robotic unloader.

Whether outfitted with roller or brush tables, the bending system creates precise bends without sacrificing surface quality due its folding style. Rather than wiping against material, adjustments are made for the necessary material radius on multiple axes as the folding beam actuates.

As for materials used annually, the company consumes 1 million lb. of anti-reflective coated glass, 1 million lb. of 5052-H32 aluminum alloy; 300,000 lb. of 304 stainless steel and 200,000 lb. of various aluminum-extrusion profiles.

No-Mark Bending

While MRI continues to use other panel benders, where the absence of marking is important it employs the RAS metal-folding system, installed in July 2018. “In fact, we’re now transferring as many parts—profiles and essentially completed chassis—as possible from our other machines to the RAS.”

Why? “Because,” says Dunn, “the folding technology behind this equipment eliminates the tools that slide over, stretch, mark and scratch the material during bending while increasing bend quality and accuracy.”

Here’s how. Using an optical scanner, the Multibend RAS 79.31-2 measures the blanks, held in place by blank-loading suction cups on the load table, which ensures accuracy of the finished partwhile accelerating cycle times because as one part bends another part is scanned. Additionally, crowning is not necessary due to a proprietary ‘beam-in-a-beam’ folding-beam design. In short, the rigidity of the machine yields consistently straight parts without the need for a maintenance-prone mechanical crowning system.

The system’s main manipulator rotates and moves the workpiece with a 0.001-deg. rotation angle and 0.004-in. linear accuracy; the 3D folding-beam movement of the system’s up-down tools enable scratch-free bending. The tab tools enable the formation of complex geometries.

Moreover, the system’s 120.5-in. maximum working length provides MRI with the length and capacity required for parts production, while the tool changer can set up any tool length in seconds.

Even on 10-ft.-long parts, “we are achieving bend-angle/flange-length accuracies as tight as ±12 to 15 min. of arc and ±0.001 to 0.003 in. down the entire length of the part,” says Dunn, adding that the part-to-part variation is so good that “it rarely requires much, if any, operator correction.”

Speed Drives Innovation

“The RAS equipment is super-fast and super-efficient,” continues Dunn. That’s the good news, but it brought a challenge. Conventional means for offloading the large formed parts couldn’t keep pace with the RAS equipment. While MRI bought the RAS with dual-gantry auto-load technology, capable of loading two 36-in. stacks, or 600 sheets, the company’s parts are so large that the system had to stop every couple of minutes for offloading.

That didn’t last long, says Dunn, as MRI soon added a six-axis robotic unloader and skeletized the parts—bending four parts on a skeleton. A fiber laser perforates those parts so that once bent, the operators, and now the robot, snap out the bended parts, with the robotic unloader providing for fast offload.

“With the skeletized parts and the RAS bender and robotic unloader, we’re producing and unloading parts faster than ever,” says Dunn. “Our system can run from 10 min. to a couple of hours before operators need to step in to remove the full pallets.”

MRI’s bending improvements have resulted in labor savings, increased capacity and accuracy. Moreover, says Dunn, “because the corner fitup is the best our welders have seen, weld time is down and quality is up, while in product assembly everything fits, eliminating the need for filing, drilling or forcing parts together.” MF