Page 17 - MetalForming September 2009

repairing die sets and grinding tools, and downtime due to damaged dies has been reduced by more than half.
Stamping Big Parts Better than Fabricating
Helping customers meet cost-down goals from year to year has GMP work- ing more often than ever on collabora- tive engineering projects with its cus- tomers. Some of the results of these programs, described by Mallmann, include modifying stamping tools to reduce blank size, and combining oper- ations in its dies to eliminate secondary operations. The firm also has invested recently in two laser-cutting machines to allow it to perform laser blanking for relatively low-volume parts—2000 to 5000 per year—rather than suffer the expense of building a blanking die.
Mallmann describes one significant collaborative project in which GMP con- verted a fabricated door assembly for a skid steer into a set of stamped components that now are robotically welded on the
GMP production floor. “One robot in the assembly and welding cell acts as a material handler, holding and manipu- lating the parts—including the heavy, 173-lb. drawn shell, of 6-mm-thick cold-rolled steel—while a second robot performs the welding operation,” he says.
Redesigning the assembly with stampings—a drawn shell for the door skin, produced on the firm’s 1500-ton tandem presses, and several stamped brackets—rather than fabricating the parts provides dramatically improved dimensional repeatability. “The dimen- sional stability achieved by deep draw- ing the door skin allows us to employ robotic arc welding for assembly,” says Mallmann. “We began working on this project with our customer fours years ago, and it’s now been production since 2008. The appearance of the door is improved, and we deliver the door as one piece to the assembly line rather than two separate fabricated pieces, simplifying the assembly process for our customer.” MF
write no. 13
www.metalformingmagazine.com
write no. 14
METALFORMING / SEPTEMBER 2009 15