WORKHOLDING, ACCESSORIES & BARFEEDS CLAMPING DOWN ON INEFFICIENCY
Enhanced A single clamping
productivity upfor grabs
Steed Webzell reveals how a selection of manufacturers is using the latest workholding
innovations to great advantage
Without being able to quickly change
chucks to accommodate varying
workpiece diameters, set-up times
are prolonged and ef ciency falls. Cutting
tool manufacturer LMT Fette, based in
Schwarzenbek, Germany, has addressed
this challenge by employing Schunk (https://
is.gd/nuyevi) quick-change jaw and chuck
technologies on a universal lathe. The result
is that even rush orders from other business
units can be handled during production,
without impacting the company’s overall
performance.
When Thomas Frankenberger, machine
operator at LMT Fette, recalls the strength it
took to change lathe chucks in the past, it is
still possible to see the stress on his face:
“Exact positioning was always an art when
you had a 500 mm lathe chuck weighing
220 kg. Even with two people, it was a
challenge to screw the lathe chuck on to the
ne-threaded draw tube. If you were off by as
little as 0.5 mm, it wouldn’t work.”
Trying to force the screw would ruin the
thread, which would spell big trouble. In
extreme cases, the draw tube would have to
be re-machined using a thread restorer.
“In the past, every time you changed the
chuck it would require time, manpower,
instinct, experience and physical strength,”
says Frankenberger. “Now that we’re using
the Schunk quick-change system, I can
easily change the chuck by myself with much
less effort and far less risk of accidents.
It used to take 45 to 60 minutes,
sometimes with two colleagues, but now it
takes just 15 minutes to do a complete
chuck change with only one operator,
including all secondary tasks, such as
cleaning, oiling and storing the second lathe
chuck.”
Instead of using multiple fastening
screws, the patented Schunk Rota FSW
quick-change chuck system is released and
screw is enough to
lock the Schunk Rota
FSW chuck quickchange
system
locked with a single clamping screw. Using a
exible adapter, the draw-tube of the lathe
can be automatically connected to the lathe
chuck and centred with precision, due to a
patented exible taper. In addition, a
patented dual-stroke system ensures high
pull-down forces, a at work surface, and
maximum rigidity in the connection. To
eliminate the possibility of operating errors,
a display continuously informs the operator
of the current locking status.
“Once I’ve positioned the lathe chuck,
I tighten the screw with the torque wrench,”
explains Frankenberger. “The chuck aligns
itself, is automatically centered and then
clamped. It hardly takes any strength.”
Remaining in Germany, another
investment project has proved particularly
fruitful at the Waldstetten facility of WESA
GmbH, a CNC subcontract machining
specialist serving sectors such as
automotive, where customers include
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