Performance upgrade
High-capacity feeding system for
Europe's specialist for solid construction timber
New sawmill infeed boosts capacity significantly.
Rubner Holzindustrie in Rohrbach an der Lafnitz (AT) is among Europe’s leading specialists for solid construction timber. This family‑owned company, now in its fourth generation, has been processing spruce, fir and pine into high‑quality semi‑finished products for timber engineering sector for almost 100 years.
With future investments in a new sawing line in mind, the existing sawmill infeed system also needed to undergo fundamental modernisation – providing the basis for higher performance and long‑term growth potential.
Task
The existing infeed system no longer met the planned performance requirements. The objective was to develop a new, compact and high‑performance sawmill infeed that would reliably support future capacity expansions.
One of the main challenges were the limited spatial conditions on site. The premises are confined by existing buildings, drying chambers and the Lafnitz river – making a compact plant layout absolutely essential.
In addition, the existing system had to remain in operation during the installation and commissioning of the new technology in order to ensure uninterrupted production. This required precise planning and implementation carried out in parallel with ongoing operations.
Solution
HOLTEC developed a high‑performance, space‑optimised infeed solution whose core elements include three Logrunners, a tandem step‑feeder and an enhanced turning device. Feeding the sawing line from both sides enables a compact layout while delivering high performance.
The process begins with buffering and separating the logs via a low‑wear chainless system. A Logrunner accelerates the logs before a measuring conveyor, equipped with a 2D light grid, captures their geometry. Existing components at the customer’s site were integrated wherever economically sensible – entirely in the spirit of a customised solution.
To determine the optimal log orientation, a 180° rotation is performed when required using the newly developed turning device. Through targeted design optimisations, moving masses were reduced, acceleration times shortened and maintenance points minimised.
Maximum utilisation of the sawing line is ensured by the dynamic gap control system “GapControl” in combination with two Logrunners. It enables transfer with minimal log spacing – a key factor for throughput at moderate line speed.
Implementation was completed in only around three months between the start of installation and the first log. Thanks to meticulous planning and close collaboration, the schedule was even exceeded by ten days.
The result is a potential capacity increase from 400,000 to up to 600,000 solid cubic metres per year – a 50% performance boost. At the same time, the low‑wear chainless system reduces operating costs and fits perfectly with Rubner’s sustainable corporate philosophy, which is based on regional raw material sourcing and maximum added value.
HOLTEC’s reliability and the trust we were able to place in their way of working enabled smooth and efficient project execution.
Albert Weissensteiner
General Manager Rubner Holzindustrie
A strong and successful collaboration:
Team Rubner: (back row, from left to right):
Rene Karner (Technical Manager),
Erich Waldl (Head of Metalworking Shop),
Michael Fuchs (Head of Electrical Engineering),
Fabio Weber (Head of Saw Maintenance and Project Manager),
Albert Weissensteiner (CEO)
Team Holtec: (from top to bottom)
Tim Weiler (Electrical Engineering Department),
Fabian Bannert (Project Manager),
Udo Hörnchen (Technical Manager)
