Bernt-Ove Andersson, Marketing Manager at Renholmen, in the Rauma sawmill. The order placed by Metsä was the largest in the company’s history © Renholmen
“With our Rosy, which we will present exclusively at the Ligna fair, we successfully automated the entire lumber handling process from green to dry sorting. This way, the plant operators will no longer work close to the line, but in a central control room. This is our understanding of modern and safe workplaces,” Bernt-Ove Andersson, Marketing Manager at Renholmen, summarizes.
The sawmill of the future
Just a few months ago, the Metsä Group’s newest sawmill was opened in Rauma in southwestern Finland. Located right next to the harbor, up to 1.5 million m³ of pine logs are to be processed there each year. Metsä’s goal is to fully automate the entire lumber production process. For the wet sorting technology, including two stacking lines, the group commissioned Renholmen, a company which has been focusing on this topic for many years. The result of the cooperation is Rosy. i.e. Robovision System, a robot and image processing system for the detection and handling of defective lumber. A total of six of these machines are used in Rauma: four of them on the two parallel, 300-meter-long green sorting lines and two more on the dry sorting line, which was delivered by a different machine manufacturer. “The Rosy system is also compatible with other manufacturers’ machines and plants,” Renholmen emphasizes.
“Rosy does the visual inspection work of an employee. The image processing system scans each board in detail and generates the necessary information so that the robot can act,” Andersson explains. Depending on the situation, the machine lifts pieces of wood lying on top of each other onto a free space on the chain conveyor or removes damaged pieces of wood from the process. Another Rosy does the same work at the subsequent stacking machine.
“For a completely unmanned sawmill, however, it is necessary to cover several sawmill areas. A good example is our stick scanner, which automatically detects damaged sticks and removes them from the process. Other examples are the automatic wagon and stick transport systems. Wagons and sticks are automatically returned after drying, final stacking and packaging and are reintroduced at the beginning of the process. In order to guarantee an uninterrupted flow of material, we also included several buffer zones in between,” Andersson tells us.
Concentrated Scandinavian expertise
Use of a robot at the sorting line: A total of six “Rosy” robots have been installed in Rauma, where they enable unmanned lumber handling © Renholmen
Rosy’s creator is Renholmen, a traditional Swedish company based in Byske, which has seen strong growth in recent years thanks to its innovative solutions and a good order situation. With its 60 employees, the Swedish machine manufacturer generated record sales of over €30 million last year. The company sees “reliable project management, innovation and high quality” as the keys to its success. Renholmen’s core market is Scandinavia but the company also sees good opportunities in the rest of Europe: “We offer solutions for companies of all sizes. In addition to exciting large-scale and high-capacity projects like the one at Metsä, we particularly value the many years of cooperation with many small and medium-sized companies,” Andersson explains.
