. . . stAmping
by Gary S. Vasilash
> Editor-In-Chief
u Setup for the SchmalbandUmform-Laserschweiß process
performed by Freudenberg Sealing
Technologies in its facility in
Weinheim, Germany, that uses a
CO2 laser to cut and weld sheet
metal that's used to produce steel
rings that are used for radial shaft
seals for several transportation
applications. The process replaces
a stamping and forming operation,
and results in as much as a 73%
savings in engineered scrap.
notwithstanding, cuts tend to occur.
They have had no injuries related to SUL
after two years in operation.
Another beneft is that SUL creates a
more precise part. The metal cases have
rubber molded into them to create the
seal. If the dimensions of the case aren't
precise and repeatable, then the molding
leads to a fash defect, which has to be
manually removed. They've found that
the Cpk for the SUL process is far better
than that provided by stamping, which,
as Ruhan points out, not only means
they don't have to perform the secondary
fash removal, but that it "provides more
quality to the fnal customer."
By in large in Germany, it seems, there
is a greater awareness of/concern
about CO2 emissions. And Ruhan
cites a savings from SUL even in that
context. There is less steel required, so
less CO2 generated to produce the steel
in the frst place; less steel has to be
transported to the Freudenberg factory
in Weinheim so there is less exhaust
from the trucks; less scrap steel is
shipped back to the steel supplier, again
a CO2 reduction.
If there is a weak point in this, it is
one that is more psychological that
physical. Unlike the rings made with
the presses, there is a weld seam on
the OD of the SUL-produced part.
Ruhan says that Freudenberg R&D;
personnel have tested and analyzed
the welds and determined that the
welds are actually stronger than the
parent material.
"We now have produced more than
50-million rings over the previous two
years. The seam is not the weak point,"
Ruhan says.
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