PENGARUH PENGERINGAN VAKUM TERHADAP KEKUATAN MEKANIK LAPISAN KAYU TERAS DAN GUBAL DARI KAYU KUMEA BATU

Abstrak

The purpose of this study was to determine the effect of vacuum pressure change and temperature on woodvacuum drying processes, on the mechanical strength of the core layer and sapwood of kumea stone wood (manilkarramerrilliana, H.J.L). The method of achievement is to vary the vacuum pressure of 30 kPa, 65 kPa and 100 kPa, withvariations in drying chamber temperature of 50oC, 65oC and 80oC. The dimensions of wood are 25 cm x 2.5 cm x 1.0cm, both heaters as a convection heat source are installed at the bottom of the wood in the drying chamber. The test wascarried out for 200 minutes and every 20 minutes the wood mass was measured. Observation results in the dryingchamber, obtained a degree of dryness that varies from wood. Then testing the mechanical strength of wood at theUniversal Testing Machine was carried out. The test results were analyzed, so that the flexural strength (MoE) andfracture strength (MoR) of wood were obtained. Testing at a vacuum pressure of 30 kPa and a temperature of 80oCresulted in the greatest flexural strength (MoE) for the core and sap layers, namely 976.73 kg / cm2 and 883.71 kg / cm2,while the greatest fracture strength (MoR) for the porch and sapwood layers was obtained on testing vacuum pressure 65kPa and tempur 80oC at 17.87 kg / cm2 and 15.91 kg / cm2. To produce good flexural strength (MoE) and fracturestrength (MoR), vacuum drying of the core layer and sapwood of kumea stone (manilkarra merrilliana, H.J.L) must becarried out at a vacuum pressure of 30 kPa and a temperature of 80oC.