窰乾溫度對桂竹機械性質之影響

The Effect of Kiln Temperature on the Mechanical Properties of Makino Bamboo

吳學旦(Hsueh-Tan Wu) ； 藍浩繁(Haw-Fun Lan)

《林產工業》 5卷1期 (1986/03) Pp. 15-23

摘要

本試驗之目的在於探究窰乾溫度對於桂竹機械性質之影響，以期能獲知快速經濟之乾燥處理法，試材為工藝常用之桂竹圓桿材。窰乾溫度分別定為60°、70°、80°、90°及99℃之恆溫乾燥，濕球差度一律為10℃，另設一組氣乾材為對照組。試驗結果顯示：1. 只要維持適當之窰內溫度，濕球差度維持10℃，提高窰乾溫度可大幅縮短乾燥處理時間並保持竹材不發生開裂。2. 乾燥後之竹桿表皮顏色係隨窰乾溫度之增高由淡黃至黃而淡褐色。3. 窰乾溫度愈高，乾燥材比重隨而增加，即其收縮率增大。4. 抗壓、抗張、抗彎及抗劈裂強度均隨窰乾溫度之增高而增大。5. 各力學強度之比強（specific strength）亦隨窰乾溫度之增高而加大，顯示高溫快速乾燥可獲高強度之乾燥材。6. 較高窰溫所乾燥出之試材其吸濕性，相對減低。

關鍵字

窰乾溫度 ； 濕球差度 ； 機械強度 ； 比強 ； 吸濕性

並列摘要

The purpose of this study was to investigate the effect of kiln temperature on the mechanical properties of makino bamboo pole and thereby to acquire a swift, and economical drying schedule. Constant kiIn temperatures namely 60, 70, 80, 90, and 99℃ were respectively used to dry each batch of the bamboo. Constant wet bulb depression 10℃ was used in each charge of the experimental schedule. Air seasoned materials were set up for contrast. The experimental results are summerized as follows: 1. As the higher kiIn temperature was applied, the drying rate would accelerate to a considerable extent, wet bulb depression of 10℃ could keep the bamboo drying without any split in each charge at different kiIn temperatures. Apparently, the kiIn huminity would bear a close relation to drying this species of bamboo. 2. The colour of the dried bamboo changed from light yellow to light brown as the kiln temperature increased from 60°C separate kiIn charge. 3. The specific gravity of the makino bamboo was increased as the higher kiIn temperature was applied. It denoted that the higher temperature caused more shrinkage on the dried material. 4. Compression and tension parallel to grain, static banding and cleavage strength increased whiIe the higher drying temperature was applied too. 5. The specific strength was increased whiIe the bamboo was dried with higher temperature. This denoted that higher temperature would reduce the drying time and produce higher strength dried products. 6. The higher kiIn temperature was used to drying, the lower hygroscopicity of the bamboo would be acquired.

並列關鍵字

Kiln temperature ； Wet buld depression ； Mechanical property ； Specific Strength ； Hygroscopicity