A flexible manufacturing system at work, with material towers connected to one or multiple lasers or other cutting machines, is a symphony of material handling automation. Material flows from tower cassettes to the laser cutting bed. Cutting commences just as the cut sheet from the previous job emerges.
Dual forks lift and remove the sheet of cut parts and transport it for automated sorting. In the most advanced setups, mobile automation—either automated guided vehicles (AGVs) or autonomous mobile robots (AMRs)—retrieve the parts and move them on to bending.
Walk to another section of the plant and you don’t see a soaring, synchronous symphony of automation. Instead, you see teams of workers dealing with a necessary evil that metal fabricators know all too well: sheet metal remnants.
Bradley McBain is no stranger to this conundrum. As managing director at MBA Engineering Systems, McBain is the U.K. representative for (among other machine brands) Remmert, a German company that manufactures sheet metal cutting automation equipment that’s machine brand-agnostic. (Remmert sells directly in the U.S.) Multitower systems might serve several laser cutting machines, a punch, even a plasma cutter. Flat sheet towers even can be combined with Remmert’s tube handling honeycomb towers that deliver tube to tube lasers.
ASD Executive Networking Event
At the same time, McBain works with fabricators in the U.K. that deal with remnants. Occasionally he might see an operation that organizes remnants carefully, storing them vertically for easy access. These high-mix operations work to get what they can out of the material they have. That’s not a bad strategy in a world of high material prices and supply chain uncertainties. And with remnant tracking in nesting software, along with the ability of laser operators to “drop in” certain parts right on the laser cutting machine control, programming cut programs on remnants isn’t too arduous a process.
That said, operators still need to physically handle the remnant sheet. It isn’t a lights-out, unattended affair. For this reason and others, McBain sees many fabricators taking a different approach. Because remnants are just too costly to manage, cutting machine programmers use filler parts to fill out a nest and achieve high material yields. Of course, this builds up work-in-process (WIP), which isn’t ideal. And in some operations, there’s a not-so-small chance that the extra WIP won’t be needed. For this reason, many cutting operations simply send remnants to the scrap pile and just deal with less-than-ideal material yields.
“The remnants, or oddments, typically go to waste,” he said. “In some situations, if you have a large remnant left after cutting, it would be picked out and put in a rack manually to be used at some later date.”
“In today’s world, this makes neither ecological nor economic sense,” said Stephan Remmert, owner and managing director of Remmert, in a September press release.