Flexible, high-performance sorting line

“Given our requirements for performance and automation, Springer is the first choice in the sawmill sector,” Dr. Stephan Lang, CEO of the Rettenmeier Group, emphasizes. “The close collaboration and decades of experience at almost all of our production sites were once again the recipe for the project’s success.”

180 boards per minute – flexible and reliable

The line in Inčukalns is designed for a cutting capacity of up to 1.2 million m³ of log wood a year in two-shift operation. At its core are two lumber sorting lines that can process both main grade lumber and sideboards. Each line operates at a continuous output of up to 180 boards per minute. For Springer manager Gert Fischinger, one thing is clear: “Like at its headquarters in Wilburgstetten, Rettenmeier has a layout here that guarantees the use of highest-performance technology for years to come.”

Focus on the operator

Particular attention was paid to user-friendliness. The workstations were positioned in such a way that they enable efficiency and a good overview of the machines. Only three employees each work in sorting and in packaging.

Another requirement specified by Rettenmeier Baltic Timber was to have the highest degree of electrical and electronic automation, as the Holzkurier learned during a tour of the production site.

Wide range of sizes

The line is designed for sorting up to 700,000 m³ of finished products. In his opening speech, Dr. Lang described what this entails: “The boards sawn from around ten million spruce and pine logs enter the sorting lines. For this volume, we need high continuous performance and maximum availability.” In the Springer sorting lines, the boards are graded, sorted, cut, stored, and stacked. Boards with lengths of 2,000 to 6,300 mm, widths of 58 to 325 mm, and thicknesses of 12 to 120 mm are processed on the lines. “It makes no difference when a 12-mm-thick board is followed by one that is ten times as thick,” Rettenmeier's Chief Technical Officer, Paul Schmid, said during the tour, adding: “Such flexible sorting of such a large volume of boards is unprecedented.”

The flexible infeed is possible thanks to two E-Feeders. Goldeneye 900 scanners handle quality control in crosswise transport. A positioning slide and the E-Cut trimmer complete the core components.

The sorting line is equipped with a multi-level buffer storage for the main product and with special lifting fork boxes for the sideboards. This way, products of different sizes can be processed in parallel and without disruption.

17 transfers per minute at the packaging line

When it comes to packaging, Rettenmeier relies on a fully automatic layer cutting system with zigzag alignment. Up to 17 transfers per minute are possible. The system is complemented by a fully automatic stacking stick infeed with scanner-assisted stick ejection, as well as an infeed and placing mechanism for squared timbers. Double stacking is also integrated here. Safety strapping ensures smooth and safe handling during in-house transport. A separate package handling system with a package press is available for fresh lumber.

Robot-assisted labeling

In post-sorting, Springer’s Robotic Labeling System (RLS) was integrated into an existing line in Inčukalns. The standard solution, featuring a camera, stapler, and peripherals, applies four labels per minute on unwrapped packages and up to six labels per minute on wrapped ones. The optimized tool operates in a continuous flow, ensuring minimal loss of time. Even the refilling of the stapler is done during transport.

“This robot-assisted solution is fast, flexible, and cost-effective,” Fischinger emphasizes. Only four months passed from order to commissioning. Since it was based on an existing Springer line from 2019, the installation was completed in two weeks.