20.500.12556/RUL-158780 Izkoristek konvekcijskega komorskega sušenja bukovine diplomsko delo Utilization rate of beech at convective kiln drying B. Sc. thesis Ocenjevali smo kakovost bukovega žaganega lesa pred in po normalnotemperaturnem konvekcijskem komorskem sušenju. Pri sveže žaganih deskah smo izmerili dimenzije ter določili število in velikost površinskih razpok, poklin in poklin na grčah. Deskam smo določili še orientacijo in potek vlaken ter določili delež obarvanega rdečega srca. Po navedenih kriterijih smo deske razvrstili po kakovosti glede na direktivo Evropskega združenja za žagarsko industrijo. Po 15- dnevnem standardnem industrijskem sušilnem postopku (Tmaks = 38 °C) do končne 18 % lesne vlažnosti smo meritve kakovosti ponovili. Ugotovili smo, da se delež uporabne površine pri nižji kakovosti žaganega lesa občutno bolj zmanjša, kot pri žaganem lesu višje kakovosti. K nastalim razlikam so največ prispevale površinske razpoke in pokline, zlasti ob grčah, nastale med sušilnim postopkom. Po sušenju smo 8 % in 15 % desk iz A- in B-kakovostnega razreda morali razvrstiti v najnižji kakovostni razred C. We assessed the quality of beech sawn timber before and after the normaltemperature convective kiln drying. Dimensions at freshly sawn boards were measured and the number and size of surface cracks and fissures on knots were determined. The grain direction and orientation were additionally determined at boards as well as the proportion of the discoloured wood. Boards were according to the above criteria ranked by quality using the directive of the European organisation for the sawmill industry (EOS). After the 15-day standard industrial drying procedure (Tmax = 38 °C) to a final 18 % wood moisture content the measurements were repeated. We have found greater reduction of utilisation rate, when boards of lower quality are dried. The resultant differences have contributed most by surface cracks and fissures close to knots. After drying, 8 % and 15 % of the boards in the A- and B-grade should be classified to the lowest C-class. les bukovina konvekcijsko komorsko sušenje napake pri sušenju izkoristek wood beech convective kiln drying drying defects utilisation rate true false false P. Polčnik Slovenski jezik Angleški jezik Diplomsko delo/naloga 2024-06-20 12:38:34 2024-06-20 12:38:37 2024-07-04 03:46:10 0000-00-00 00:00:00 2016 0 Ljubljana 2016 Ljubljana IX, 39 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 630*847 2698121 DIP_Polcnik_Peter_2016.pdf DIP_Polcnik_Peter_2016.pdf 1 114C5B005046219942BA15E3327D0B3C f636f8660e9a99ff8b0a5558a471ff16829df03dca96cf441ec61e8820caf938 40dd9c88-2ef1-11ef-a73e-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186500 Biotehniška fakulteta 0 0 0