and the operators spend a lot of time just
moving material from place to place, or
if it’s congested and material handling is
cumbersome, getting some parts off the
fabrication floor and into the pressroom
might help. Large, heavy parts that are difficult to load, unload, and move, thereby
contributing to operator fatigue, might be
good candidates for in-die transfer.
Next, look at part volume. Because of
the tooling cost, small-volume part runs
made sporadically throughout the year
may not be candidates for in-die transfer. A part volume that is both large and
consistent is ideal. Although quite a bit
depends on the specific part, an annual
part volume that exceeds 20,000 is a
good place to start.
Next, look at the pressroom. Do you
have presses that can handle this sort of
thing? How deep is your well of experience concerning stamping dies?
Beyond that, it’s a matter of sitting
down with a die designer and transfer
systems supplier to see just how feasible
your part is. In addition to forming and
fabricating processes, in-die transfer is
amenable to a variety of loading options.
“One simple option is a tray,” Gunst
said. “The operator loads five or 10 parts
into the tray and replenishes the tray when
necessary. Another option is a static hop-
per, one that holds quite a bit of material.
The operator refills the empty hopper with
parts just once or twice per hour,” he said.
For really large part volumes, a big hopper
that holds an entire shift worth of mate-
rial is an option. “A conveyor moves parts
from the hopper to a tray near the infeed
side of the press,” Gunst said. “When a
sensor senses that the tray is nearly empty,
the conveyor starts and runs for a while to
refill the tray.”
Gunst recalled converting a part that
took up a lot of floor space and ran con-
tinuously on several shifts. These criteria
take advantage of in-die transfer’s two
main strengths: its relatively compact
size and fast processing speed.
“The part originally was made in four
identical workcells, including a hydro-forming process,” Gunst said. “It ran automatically, two shifts per day, five days
a week.” The in-die transfer system replaced all four workcells with one press
and one in-die transfer system, he said,
and it produced 45 parts per minute.
Finally, the process doesn’t have any
specific material restrictions. It’s suitable for forming carbon steel, stainless
steel, and aluminum, and it handles both
welded and seamless products.
Caveats in Using
an In-die Transfer
This isn’t to suggest that in-die transfer is
suitable for any and all applications. Like
everything else in manufacturing, it’s a
matter of matching this process to suitable parts. “For fabricating tube in a die,
bending to less than 90 degrees is ideal,”
Gunst said. Beyond that, in-die transfer is
good for tubes that don’t have the strict-est of tolerances.
“It is difficult to stick a mandrel inside
of a tube with this process, so if you can
live with some deformation or collapsing
in the bend zone, in-die transfer might
be an option,” he said. Because the process often results in some deformation,
it’s not a candidate for bending pipe to
make fluid transfer components. Gunst
mentioned a workaround: Do the bending on a mandrel-equipped bender and
perform the rest of the processes in an
in-die transfer system.
Eric Lundin can be reached at ericl@
Jacar Systems LLC, 10321 Arnold Road,
Fair Haven, MI 48023, 586-321-1401,
1-4: Tube Part
5: Jacar’s Micro Transfer® System
6: Die Set
7: Part-handling Rails
8: Exit Chute
For this application, the in-die forming process comprises four steps: (1) The tube enters the die, fed from an external parts feeder [not
shown]; ( 2) the ends are sized; ( 3) the ends are flared; ( 4) the tube exits the die and is deposited into a parts chute.