No abstract

The influence of oscillating climate conditions during the conventional drying of beech timber on drying time and drying quality has been analyzed. Three conventional drying cycles were carried out as well as nine cycles, in which the oscillations of equilibrium moisture content (EMC), temperature, and their combination were applied. The combinations of two amplitudes (10% or 20%) and two frequencies (3 or 6 h) were used in different test runs. Higher drying quality regarding casehardening was achieved both in runs with oscillations of EMC (gap values 2.2-2.4 mm) and in runs with temperature oscillations (gap values 2.3-2.4 mm) compared with conventional runs (gap values 2.5-2.9 mm). The oscillations of both temperature and EMC did not improve any of the observed parameters.

The paper presents results of influence of thermal modification on cutting power required for milling wood processing. The experiment was conducted for the different treatment temperatures (170°C, 190°C and 210°C) and different technological parameters of processing (feed and cutting depth). Cutting powers during milling were measured on four groups of beech wood samples, dimensions 35×16×400 mm, separately for heartwood and sapwood. The following mechanical and physical properties of the processed samples were tested: bending properties (modulus of rupture and modulus of elasticity), cross-sectional and tangential hardness, and air-dry density. The measuring device used for measuring, monitoring and displaying cutting power was developed at the Wood Machining Centre at the Faculty of Forestry in Belgrade. The results point out the differences in the powers required for processing heat-treated wood compared to untreated wood. The analysis shows that with the increase in treatment temperature, the required cutting powers decrease

AbSTRAcT• The paper presents the research of differences in quantitative and value yields, and structure of sawn timber and residues, whose appearance is caused by different methods of sawing beech logs with red heartwood. In order to achieve the goal, 45 logs were divided into three even groups and sawn into commercial timber using three methods: round, cant and live sawing. Similar quantitative yields were found for round sawing and cant sawing (60.63 % and 60.52 %, respectively)

• The infl uence of applying the oscillations of air parameters during conventional drying of beech timber on energy consumption is discussed in the paper