In the diploma thesis the defects of the spruce assortments were assessed, with their exact measurement and classification of the assortments into quality classes. In all, 30 assortments were measured with the total volume of 18.19 m³. This was followed by the sawing of logs of different diameter and a measurement of end product with the ambition of attaining the efficiency of sawing with a horizontal band sawing machine. We obtained 13.24 m³ of sawn wood and 2.88 m³ of wood for chemical processing. It has been found that the utilization of sawn wood is very high, even up to 80%. The average yield of usable sawn wood was 72.79 %. The quality classes are most influenced by the logs’ diameter, the number and type of knots and the taper. Such a high efficiency is mainly influenced by the experience of the machine operator and the quality of assortments. We have determined, that the number of ungrown knots on the assortment increases with the increase in the mean diameter of the assortment, and that the amount of sawn wood produced increases with the increase in the mean diameter of the assortment.
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