Experimental Research on Sawing Frozen Wood

Abstract

The main objective of the present research is to establish the differences in the behavior during sawing of frozen and unfrozen wood. Two species, a resinous one (spruce, Picea abies L.) and a broad-leaved one (oak, Quercus robur L.) were selected for this study. The tested wood specimens originated from the same log (one spruce log and one oak log). Half of the specimens were frozen down to –30ºC, with a freezing rate of -15ºC/h, and then maintained for 1 week in a frozen state; half remained unfrozen, as controls. Both the frozen and the unfrozen specimens were cut by means of a circular saw blade under absolutely identical conditions (same machine, same tool, same devices, and same cutting conditions), in order to determine comparatively the power consumption and the resistance specific to cutting involved in the two cases. The results revealed that freezing determines – in the given conditions – a visible decrease of the necessary cutting power and the specific resistance to cutting (by up to 46.1% for spruce and up to 47.2% for oak).