Page 26 - MetalForming June 2015
P. 26
Laser-Cutting Duo
24 MetalForming/June 2015
www.metalformingmagazine.com
department—turret presses, lasers and press brakes.
“We can turn jobs in three days typ- ically, and more quickly if required,” says Wagy. “The move to kanban has been very successful in helping us con- trol inventory and improve production efficiency.”
“Evolving into the high-mix low- volume world,” shares Prince, “required a significant investment in hiring the right people and building their skill sets. And we’ve had to improve our scheduling and develop expertise in logistics. On the fab side of the building, we often have to schedule a series of processes that follow turret-press punching and laser cutting, including bending, hardware insertion, e-coating and assembly. Logistics on the stamp- ing side are typically much simpler. And we have had to learn to commu- nicate much more thoroughly and effectively with our suppliers and our customers.
“Last but certainly not least,” Prince continues, “we’re close to investing in a new ERP system, to help us manage the rapidly increasing complexity of our business.”
Of course, as part volumes rise in fabrication—to 2000 or more typical- ly—the temptation to add hard tooling to the job, in part or in total, becomes greater.
“For example,” explains Wagy, “we can tool the complete part run in a progressive die and run from coil, or we can laser-cut blanks and move those to a secondary die and add the required bends to the parts.
“We have one laser-cut part, for example,” Wagy continues, “that requires six bends in a press brake. We’re looking at whether or not we can complete that part in a two-out sec- ondary stamping die as volumes increase.”
A Short Learning Curve that Doesn’t End
Prince and Wagy agree that while integrating new laser technology into the company’s production processes occurred relatively quickly and pain-
lessly, perfecting their use requires climbing an ongoing learning curve. In the shop, Wagy says that program- ming the cutting machines has not cre- ated any notable challenges—the firm uses FabriWin CAD-CAM software, from Metalsoft, to enter approximate- ly four new part numbers into the laser- cutting machines per week.
However, supervisor Yanel Lopez explains that learning how to fine-tune process parameters on the shop floor is where significant efficiency gains can be found. When we visited, Lopez had recently attended fiber-laser training at Trumpf, in Farmington, CT, and had picked up some CO2 operating tips at the same time.
“We’re always fine-tuning our laser-process parameters to increase speed and improve quality,” Lopez explains. “Often this means modifying the ‘tech tables’ of parameters, includ- ing gas pressure and laser power. For example, the parameters programmed into the controller relate to specific types of material and the thickness of the sheet or plate. When we have to cut a material type of workpiece thick- ness that doesn’t exactly match what’s programmed into the controller, we have to ‘dial-in’ or fine-tune the parameters.”
Asked to cite a recent example, Lopez points to the job running on the CO2 laser during my visit—the 0.060-in. cold-rolled steel sheet.
“At first, we were burning the part edges,” Lopez says. “I increased the gas pressure from 1.5 to 3 bars, and now we’re not only getting cleaner cuts but we’re cutting faster.”
On the fiber front, one operating tip quickly became evident.
“We have to be diligent about maintaining the machine and keeping the lens clean,” says Lopez. “For exam- ple, cutting the 0.312-in.-thick mate- rial can cause spatter from piercing to splash up and stick to the lens. This will diminish beam quality and cause burrs on the bottom of the cut parts. Sticking to a prescribed preventive- maintenance schedule will avoid that problem. MF
