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Radially sawn timber—the Primwood Method for improved properties

Radial gesägtes Holz—Die Primwood Methode zur Verbesserung seiner Eigenschaften

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Abstract

A new manufacturing system, the PrimWood Method, has been proposed to improve the utilization of wood. A basic concept within this method is the sawing pattern called star-sawing, which produces timber with both rectangular and triangular cross sections. This method facilitates an efficient production of radially sawn timber with vertical annual rings, without juvenile wood. The sawn timber produced in the PrimWood Method is used to produce high quality, knot-free solid wood panels with vertical annual rings. In this process, part of the timber is finger-jointed to form knot-free lengths which are glued together into a block. This block can then be divided according to thickness into thinner panels with vertical annual rings. The PrimWood Method has been tested in an industrial plant. The manufacturing system was designed for a sawing capacity of about 30,000 m3 logs, which corresponds to 16,800 m3 of star-sawn timber per shift per annum. The production of solid wood panel was then designed to give a volume of 5,800 m3 per annum.

Zusammenfassung

In der vorliegenden Arbeit wird ein neues Verarbeitungsverfahren, die sogenannte Primwood Methode, zur Verbesserung der Holznutzung vorgestellt. Ein grundlegendes Konzept dieses Verfahrens ist das Einschnittmuster, genannt „Sternsägen“, welches Nutzholz mit rechteckigen und dreieckigen Querschnitten liefert. Diese Methode erleichtert eine wirtschaftlich effiziente Herstellung von radial geschnittenem Nutzholz mit stehenden Jahresringen ohne Juvenilholz. Das auf diese Weise hergestellte Schnittholz wird verwendet, um astfreie, qualitativ hochwertige Vollholzplatten mit stehenden Jahresringen zu produzieren. Darüberhinaus werden diese Platten mit Keilzinkung versehen, um astfreie Abschnitte zu bilden, welche zu einem Block verleimt werden. Dieser kann dann der gewünschten Dicke entsprechend in dünnere Platten mit stehenden Jahresringen aufgeteilt werden. Die Primwoodmethode wurde im industriellen Maßstab geprüft. Der Betrieb war für eine Kapazität von ungefähr 30.000 m3 Roh- Rundholz ausgelegt, was ungefähr 16.800 m3 sterngesägtem Schnittholz pro Schicht und Jahr entspricht. Anschließend wurde die Produktion von Vollholzplatten auf ein Volumen von 5.800 m3 pro Jahr eingerichtet

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Authors and Affiliations

  1. School of Technology and Design, Växjö University, 35195, Växjö, Sweden

    D. Sandberg

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  1. D. Sandberg
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Correspondence to D. Sandberg.

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Sandberg, D. Radially sawn timber—the Primwood Method for improved properties. Holz Roh Werkst 63, 94–101 (2005). https://doi.org/10.1007/s00107-004-0531-9

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  • DOI: https://doi.org/10.1007/s00107-004-0531-9

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