Abstract
Grade sorting of logs in addition to diamoter sorting is a mean of customising production schedules and treatments, eg. sawing patterns and drying schedules. This paper analyses the feasibility of automatic grade sorting of spruce (Picea abies (l.) karst) saw logs by using optical log scanners, eg. shadow scanners. Differences in log geometry between grades, stands, diameter classes and log types were analysed. The material consisted of 699 logs from four different stands. It was tested if the differences in log geometry between high and low grade logs could be used for grade sorting in a logistic model. About two thirds of the logs were correctly classified into high or low grades. The methods and results are considered promising and further studies are recommended.
Zusammenfassung
Die Sortierung der Sägeblöcke im Hinblick auf Qualität zusätzlich zur Durchmessersortierung ermöglicht eine verbesserte Kundenanpassung von Einschnitt und Trocknungsprogramm. Dieses Arbeit untersucht die Möglichkeiten für eine automatische Qualitätssortierung von Fichtensägeblöcken (Picea abies (l.) karst) bei Anwendung elektronischer Meßrahmen. Unterschiede in der Blockgeometrie zwischen Qualitätsklassen, Beständen, Durchmesserklassen und Stammabschnitten wurden geprüft. Das Untersuchungsmaterial bestand aus 699 Sägeblöcken Unterschiede in der Blockgeometrie zwischen hohen und niedrigen Qualitätsklassen in einem logistischen Model zur Vorsortierung verwendet werden können. Etwa zwei Drittel der Sägeblöcke wurden korrekt eingestuft. Die Ergebnisse sind vielversprechend, jedoch weitere Auswertungen werden empfohlen.
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Jäppinen, A., Nylinder, M. Automatic sorting of spruce (Picea abies (l.) karst.) sawlogs by grade. Holz als Roh- und Werkstoff 55, 301–305 (1997). https://doi.org/10.1007/s001070050233
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DOI: https://doi.org/10.1007/s001070050233