頁籤選單縮合
題 名 | 初期含水率對木荷熱壓乾燥效果之影響 |
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作 者 | 熊如珍; | 書刊名 | 林業試驗所研究報告季刊 |
卷 期 | 3:1 1988.03[民77.03] |
頁 次 | 頁407-414 |
分類號 | 476.1 |
關鍵詞 | 木荷; 含水率; 初期; 效果; 乾燥; 熱壓; |
語 文 | 中文(Chinese) |
中文摘要 | 為探究降低初期含水率,再行熱壓乾燥,是否能避免熱壓乾燥材嚴重 內部乾裂之發生,特採省產木荷,胸高直徑50-60cm,鋸製成3.0cm與 1.5cm厚 板材,進行試驗。熱壓條件:熱板溫度174℃,熱板壓力3.5kgf/cm^2,初期含水 率分別為生材、30%、18%。結果顯示:熱壓乾燥木荷板材,自含水率 81.65%(89.56%)降至含水率6.46% (7.34%),僅費時28(94)分鐘,板厚1.5cm(3.0cm) 。降低初期含水率,可減低乾燥材內部乾裂程度,薄板乾燥效果又優於厚板者。 1.5cm厚木荷可自生材始即施以熱壓乾燥,僅發生輕微的內部乾裂及端裂;3.0cm 厚者則不宜自生材始行熱壓乾燥,否則將發生嚴重內部乾裂及端裂。 |
英文摘要 | The objective of this study was to evaluate the effect of initial moisture contents on press drying of Schima superba. Press drying was at 174℃ platen temperature and 3.5kgf/cm^2 platen pressure. The sample boards were at three different initial moisture content (green, 30%, and 18%). Boards were edged to the 5- 15cm in width, surfaced to 3.0cm and 1.5cm in thickness, respectively, and end trimmed to 80cm in length. The results showed that the 1.5cm-thick material could be dried to 0.42-6.46 percent final moisture content in 13 to 28 minutes, depending on initial moisture content. The 3.0cm-thick material could be dried to about the same moisture content (0.01-7.34%) in 37 to 94 minutes. Severe internal checks and end checks occurred in the 3.0cm-thick material when pressdried directly from the green conditions. Predrying the boards to 18 percent M. C. before press-drying prevented all of the drying defects for both the 1.5cm and 3.0cm boards. The 1.5cm-thick Schima superba boards were suited for many uses. |
本系統中英文摘要資訊取自各篇刊載內容。