High-mix, low-volume manufacturing: Greater flexibility and process reliability through automated clamping solutions
A wide variety of workpieces in small batches: what is the best way to manage high-mix, low-volume production? This was the challenge faced by Production Manager Bernd Wieser and Technical Manager Marc Schäfer at AKM Maschinenbau GmbH in Eppingen.
Whilst AKM Maschinenbau initially focused on the manufacture of milled and turned components when the company was founded in 1990, it now specialises in the construction of custom machinery. The 30-strong team develops, designs, manufactures, programmes and commissions specialised machinery for the automation, automotive, medical technology and contract manufacturing sectors. As the company’s area of expertise has grown, so too has the desire for greater flexibility and process reliability through automated clamping solutions.
“We wanted to be able to switch between a wide variety of clamping vises and fixtures at any time, as well as handle relatively heavy loads. That’s why pallet automation was the only option for us,” says Marc Schäfer. The customer requirements were therefore: full flexibility, process reliability and stable workpiece clamping. The use of clamping pyramids was intended to increase machine running times and pallet throughput. At the same time, the use of GRESSEL clamping devices ensures the compatibility of the clamping technology with existing clamping equipment.
The right clamping solution: gre4doc, M1, C2.0, SC2.0 and SC5X
Working in collaboration with GRESSEL sales representative Frank Scheurer and SCHUNK sales representative Joachim Schönberger, a suitable solution was developed for the DMU 75 monoBLOCK machine and the PH Cell 300 pallet automation system, which handles over 21 pallets. The pallets are loaded onto the SCHUNK NSL 400-Autmation Vero-S NSE 138 zero-point clamping system, which is mounted on the machine table.
The pallets are equipped with the GRESSEL gre4doc zero-point clamping system, the M1 multi-clamping system, the C2.0 centric clamping vises and SC2.0 single clamping vises, as well as the SC5X 5-Axis clamping vises. These are supplemented by accessories and an extensive range of jaws.
The measurable benefits: increased machine uptime, reduced set-up times
The M1 multi-clamping system offers a high degree of flexibility through the combined clamping of multiple and large parts. As a result, AKM has been able to increase its machine uptime by around 20 per cent, thereby significantly boosting parts production per shift. This is particularly evident in small and medium-volume production.
To enable multi-clamping in very confined spaces, AKM manufactured its own clamping pyramids, which are fitted with C2.0 centre clamps and SC2.0 single clamps. Multi-clamping reduced set-up times by around 60 per cent and significantly improved machine utilisation.
Maximum flexibility and optimum accessibility when machining individual parts have been achieved through the use of SC5X 5-axis clamping systems. The result: shorter machining cycles and 15 percent less rework, as the clamping processes are precise and reproducible.
The gre4doc zero-point clamping system was chosen to enable direct workpiece clamping and a change of clamping device in a matter of seconds. This has reduced set-up time per job by up to 70 per cent and increased productive machine time by around 250 hours per year.
With the same number of staff and machines, AKM achieved a productivity increase of around 20 percent by combining these clamping solutions. In addition, set-up times were reduced by up to 70 percent, resulting in several hundred additional machine hours per year.
Customer satisfaction: Meeting requirements, greater efficiency
“The customer requirements, namely the reduction of setup times, the increase of machine hours, the flexibility of the clamping devices, as well as easy operation and simple handling, were covered by our extensive clamping technology from the standard product range,” says Frank Scheurer, Sales Representative GRESSEL.
“We are 100 percent satisfied with the solution. Downtime on the machine has been significantly reduced,” says Marc Schäfer. The reduced set-up effort makes it possible to run in new parts more efficiently and optimise programmes via the CAM, whilst other components continue to run on separate pallets in parallel. Once optimised, workpieces that have already been started can be resumed and finished without any significant loss of precision. Overall, set-up is faster and, thanks to multiple clamping, more parts can be machined simultaneously, further reducing downtime.
