(Courtsey of FASTCO Industries, Inc.Grand
Rapids, MI)
Quality Issue:
The part shown on right had no problems in
manufacturing, but was breaking off during the assembly process. FASTCO
simulated the manufacturing process to see if any changes could be
made to alleviate the breakage problem. The simulation showed large
strains at the section where the part was breaking in the assembly.
FASTCO simulated a number of design options and found one that reduced
the critical strain without the added tooling cost. Parts were formed
according to the redesigned forming operations. The customer has not
reported any part cracking after the design changes made on the basis
of simulation. Costly trial and error development on the machine was
avoided through NAGSIM.2D simulation.
Resolving Manufacturing Problems:
Picture on right shows a cup type part that
was cracking on the outside free surface during the final forming
operation. The forming sequence for this part was simulated using
NAGSIM.2D. The results showed large strains in the part at and near
the free surface of the part. FASTCO investigated a number of forming
design changes. One change showed much less strains in the cup at
and near the free surface. Tooling changes were made and the part
was manufactured with the redesigned tooling resulting in greatly
reducing the defect.