UPON THE WORKABILITY BY SAWING OF FROZEN AND UNFROZEN OAK WOOD

Mihai ISPAS
Prof.Dr.Eng. - Universitatea "Transilvania" din Brasov - Facultatea de Industria Lemnului
Address: B-dul Eroilor nr. 29, 500036 Brasov, Romania
Tel.: +40 268 419581. Fax: +40 268 419581.
E-mail: ispas.m@unitbv.ro

Abstract: The paper presents the results of a research performed in order to establish if oak (Quercus robur L.) timber in frozen state (in winter) has different properties than unfrozen timber with regard to its processing. Oak timber specimens, cut from the same log, half of them frozen at -30ºC and half unfrozen, were sawn under absolutely identical conditions (same machine, same tool, same devices and same cutting conditions), in order to determine comparatively the energy consumptions involved in the two cases. The results revealed that freezing determines a visible decrease of the necessary power for cutting, respectively an apparent lowering of the mechanical strengths.

Key words: frozen wood, oak, cutting power, energy consumption, mechanical strengths.

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*** EN 13183-1:2003. Moisture Content of Timber. Part 1: Determination by Oven-Dry Method.