LEWA Attendorn relies on STARK Spannsysteme

Transcription

LEWA Attendorn relies on STARK Spannsysteme
ZERO POINT CLAMPING SYSTEM
LEWA Attendorn relies on STARK Spannsysteme
Minimising setup times
Increased flexibility, setup time minimisation, increased productivity and the related time savings are
profit-making factors for commercial success these days.
Due to the ever increasing variety of parts, the usage of widely varying materials of widely varying
dimensions and the need to be able to quickly and promptly satisfy customer requirements, at Lewa Attendorn it was considered necessary to optimise the machining section and make it more cost-effective.
Lewa Attendorn GmbH, a medium-sized business with more than 150 qualified staff is a turnkey supplier
for demanding custom solutions in the area of pipe shaping technology, advanced robot systems and a
partner for the CNC manufacture of complex turned, milled and bored parts. In the vocational training
centre alone, Lewa trains up to 220 trainees for local industry along with its own trainees in the wellequipped training workshop and as a result is the largest vocational training centre in the region. The
tasks the business undertakes range from drilling and milling jobs, turning and grinding to complete robot
welding systems.
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ZERO POINT CLAMPING SYSTEM
Modern production systems and machinery operate ever faster and more efficiently. The systems
are increasingly operated at the limit or even over
the nominal limit. To counteract this situation and
while searching for potential for optimisation and
savings, at Lewa it was concluded that the only
solution was to shorten the setup times and to do
this by using a zero point clamping system.“On
what are do manufacturers concentrate today
to be more cost-effective? In the reduction of
non-productive time, that is minimising the setup
times to make manufacturing more cost effective
and as a result more competitive“, says Rainer
Frisch, head of machining in production at Lewa
Attendorn. So the search started at Lewa for the
right zero point clamping system manufacturer.
After considering all the well-known providers, the
team at Lewa Attendorn decided for the zero point
clamping system manufacture by STARK Spannsysteme in Goetzis, Austria. STARK Spannsysteme is part of the Römheld Group and is one of the
world‘s leading suppliers of zero point clamping
systems. „At the start we were very concerned, as
we had a zero point clamping system from another
manufacturer in use on a machine and had problems with inaccuracies and the mounting plates
had become distorted. On one occasion the entire
machine was suspended from the crane hook as
the operator could not see that the workpiece was
still clamped“, explains Rainer Frisch. Robert Hartmann, head of sales at STARK Spannsysteme,
was however able to very quickly clear up these
doubts: „On the STARK system the release is
hydraulic, as a result the pallet is raised on release
and the operator can clearly see that the pallet
has been released. On other systems there is only
simple locking and the operator has no indication
of whether the workpiece is clamped or released.“
The team at Lewa also had the opportunity to view
the zero point solution from STARK live on site at
another organisation and to talk to the responsible machine operators in this organisation, which
further reinforced their decision for the STARK
zero point solution.
Speedy zero point clamping system
Initially STARK equipped one DMU 100 at Lewa
with the Speedy 2000 zero point clamping system.
Here it was decided to use a modified octuple
design with a somewhat larger spacing to achieve
better turning moments. On this system the retractable nipples are fixed positively and with high
precision by spring force. Release is hydraulic.
Thanks to the special nipple shape, there is no
damage to the fits during the pallet change. As the
clamping cycle on this machine is frequent, it was
possible to significantly reduce the clamping time
in a very short time and as a result considerably
increase the productivity of the machine. Once
Lewa was fully satisfied with the quality, the accuracy, the clamping process and the setup time, two
further DMU 100 were also equipped with STARK
clamping systems, as well as a large Wotan boring
machine. On this Wotan machine, e.g. frames for
bogies or complex cast structures or welded structures are manufactured in small production runs or
as one-offs – from face milling and shoulder milling
with high feed rates to boring, thread cutting and
reverse countersinking.
Three DMU 100 and the Wotan
boring machine for manufacturing
large parts
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ZERO POINT CLAMPING SYSTEM
DMU 100: optical release check – „Thank heavens for
hydraulics!“ The Speedys lift the pallet on release. Thus
safe handling is guaranteed.
Wotan: machine table with right-angled clamping plate
1 and right-angled clamping plate 2. Loading is undertaken using the overhead crane. The „third hand function“
and optional clamping check are also an advantage
during handling like the optical release check.
Setup and storage stations: handling is crucial with large parts: the pallet for the Wotan is turned for setting up
Wotan: machine table with right-angled clamping plate
1 and right-angled clamping plate 2. Loading is undertaken using the overhead crane. The „third hand function“
and optional clamping check are also an advantage
during handling like the optical release check.
Capacity gain and more flexibility during the
manufacture of large parts
tegrated „third hand function“. STARK systems
with the „third hand function“ keep the workpiece
or the pallet in the correct position once securely
engaged. Workpieces and pallets are then secured against falling out and no longer need to be
held by the operator. The system is also prepared
for the „clamping check“ option that can be easily
added later. „Here we have a right-angle clamping
plate 2500 mm high. At the moment 2 clamping
plates are fitted, one 1600 mm wide and the other
1200 mm. The clamping plates have been equipped with the retractable nipples. Speedy 3000 are
also installed in turn on the clamping faces on the
In collaboration with STARK, it was decided at
Lewa to equip the Wotan machine with the Speedy 3000 zero point clamping system. During this
process 5 rails each with 3 Speedy 3000 were
attached to the machine table (2000 x 2500 mm).
The reinforced version used here permits a maximum load of 25 t (!). Either pallets or workpieces
can be placed directly on these rails. In addition, a
Römheld hydraulic unit was also supplied for the
clamping and releasing; this unit also has an in-
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ZERO POINT CLAMPING SYSTEM
right-angle clamping plates, so the pallets can be
changed quickly“, explains Rainer Frisch; Robert
Hartmann adds: „The entire zero point clamping
system from STARK is a modular system. Small,
medium-sized or large pallets can be clamped by
using the narrow clamping plate and the wider
clamping plate or by using both clamping plates,
and there is access to the workpiece from all three
sides.“ The clamping frames that Lewa uses here
are 2.40 m high and 3.50 m wide and weigh approx. 3.5 tonnes, with the workpiece alone weighing approx. 1.2 t. „For us the situation is much
easier and we gain an immense amount of time.
We have reduced the setup time by several times
over and can now even produce on the machine
with 3 shifts, which of course brings a capacity
gain. Before we lost a large amount of time during
setup and during clamping on the clamping plate.
We spent approx. 5 hours setting up and clamping
alone and the machines were stationary during this
time“, says Rainer Frisch. By using the zero point
clamping system from STARK, at Lewa it is now
possible to clamp the workpieces that are to be
machined next at the same time as workpieces are
machined. A dedicated setup station in front of the
machine has been established for this purpose.
„While the workpiece is machined, we are setting
up, as a result we do not lose any time any more
and everything is also considerably more convenient“, adds Rainer Frisch.
Lewa application report fact box
Right-angled clamping plate 2 with eight STARK
Speedy classic 3 zero point clamping systems
Dimensions (WxDxH):
1000 x 1000 x 2500 mm
Zero point clamping system:
STARK Speedy classic 3
Configuration:
8-times spacing 600 x 600 mm
Max. load on all Speedy:
20 tonnes
Insertion force:
240 kN
Release pressure:40 bar using hydraulic unit supplied
Options:
third hand function using hydraulic unit
Prepare for clamping check
Optical release check (lifting function)
Taurus Wotan Cutmax3 PT boring machine
Machine table with STARK zero point clamping
system:
Machine table dimensions:
2000 x 2500 mm
Max. table load:
25 tonnes
Zero point clamping system:
STARK Speedy classic 3
Configuration:
15-times spacing 600 x 600 mm
Max. load on all Speedy:
37.5 tonnes
Insertion force:
450 kN
Release pressure:
40 bar using hydraulic unit supplied
Options:
optical release check (lifting function)
DMU 100 P duoBlock five-axis milling
machine (three machines)
Right-angled clamping plate 1 with 12 STARK
Speedy classic 3 zero point clamping systems
Dimensions (WxDxH):
1600 x 1000 x 2500 mm
Zero point clamping system:
STARK Speedy classic 3
Configuration:
12-times spacing 600 x 600 mm
Max. load on all Speedy:
30 tonnes
Insertion force:
360 kN
Release pressure:40 bar using hydraulic unit supplied
Options:
third hand function using hydraulic unit
Prepare for clamping check
Optical release check (lifting function)
Machine table with STARK Speedy classic 2 zero
point clamping system
Machine table dimensions:
ø 1100 x 900 mm
Max. table load:
2 tonnes
Zero point clamping system: STARK Speedy classic 2
Configuration:
8-times spacing 240 x 240 mm
Max. load on all Speedy:
8 tonnes
Insertion force:
160 kN
Release pressure: 40 bar using STARK pressure
booster supplied
Options:
optical release check (lifting function)
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ZERO POINT CLAMPING SYSTEM
Conclusion
STARK Spannsysteme GmbH
Based in Goetzis, Austria
30 staff (Römheld Group: 580 staff with an annual turnover of around 90 million euro)
With the procurement of the zero point clamping
systems from STARK, Lewa is continuing its drive
for perfection, quality and adherence to deadlines.
Thanks to the additional capacity, flexibility and
the reduction in the setup times, at Lewa it has
been possible not only to achieve increased parts
accuracy, the processing times have also been
significantly reduced. This time saving of course
represents a significant competitive advantage and
Lewa is now able to better meet customer‘s technical, schedule and also economic requirements.
Rainer Frisch: „We are very satisfied with the
collaboration with STARK. Starting from the constructive meetings during the planning phase to the
service and support on site.“
„Finally everything hinges on a single point: to reduce the downtimes to be more cost-effective and
increase the turnover – and we have achieved this
goal with the zero point solution from STARK“, explains Hermann-Josef Bettendorf, member of the
senior management and head of sales at Lewa, in
conclusion.
Metal machining sector. Developer and manufacturer of products and systems for efficient
manufacturing.
Emphasis Products focused on quality.
Strengths
Specialist consultation and comprehensive
service.
www.stark-inc.com
www.lewa-attendorn.de
Sources:
Lewa Attendorn GmbH, Gildemeister AG, Taurus
Wotan, STARK Spannsysteme GmbH,
Römheld GmbH
Photographs: STARK Spannsysteme GmbH
i.V. (authorised signatory)
Robert Hartmann, STARK Spannsysteme GmbH
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