提高烘干法检测木材含水率精度的方法  

Wood Moisture Content Detection by Drying Methocl

作　　者：张肖凯 王箫笛 赵明阳 唐斌 万川 刘洪海[1] Zhang Xiaokai;Wang Xiaodi;Zhao Mingyang;Tang Bin;Wan Chuan;Liu Honghai(Nanjing Forestry University,Nanjing 210037,P.R.China;Macio Casa Furnishings Co.,Ltd.)

机构地区：[1]南京林业大学,南京210037 [2]玛格家居股份有限公司

出　　处：《东北林业大学学报》2023年第12期110-114,119,共6页Journal of Northeast Forestry University

基　　金：国家自然科学基金项目(31870545);南林-玛格校企合作项目(028104514)。

摘　　要：板材常规干燥前通常将其两端锯截的含水率试片利用烘干法估算其含水率,估算值对木材干燥工艺制定及过程控制非常重要。以胡桃楸(Juglans mandshurica Maxim.)木材试件为试验对象,对含水率在试件纵向及横向的分布规律、试片平均含水率的计算公式、试件含水率估算值与实测值的差异进行了讨论。结果表明:①在木材纵向,试片的含水率与锯截位置显著相关,试片间距越大,含水率差异越显著;②各试片的含水率分布规律具有一致性,含水率由髓心沿弦向、径向降低。含水率等高线与试件的年轮走向趋势一致;③以小木块质量作为权重计算的试片平均含水率与算术平均法计算结果仅相差0.1%左右。该方法适合精度要求更高、板材尺寸大、水分分布不均时使用;④试件的含水率估算值比实际值大3%左右,可以使用锋利的切割工具、降低含水率试片的干燥温度以及使用在线装置及时称质量等方法优化试验操作来减小误差。Before drying timbers,the moisture content(MC)of wood is usually determined using the wood slices sawed at both ends of the timbers.MC estimation is very important for wood drying process formulation and process control.The wood specimen of Juglans mandshurica Maxim.was taken as the test object.The distribution law of MC in the wood fiber and transversal direction,the calculation formula of average MC of test pieces,and the difference between the estimated MC of test pieces and the measured value are discussed.The results showed that:(1)In the fiber direction,the MC of test pieces is correlated with the sawing position.The larger the spacing of test pieces,the more significant the difference of MC.(2)MC distribution law in transversal direction of each test piece is consistent,showing MC decreasing along tangential and radial direction.Meanwhile,the rings direction of the test pieces can be identified according to the MC contour map.(3)There is no difference between the results of calculating the average MC of test pieces by using the weight of small wood block and arithmetic average method,only about 0.1%difference.This method is more suitable for higher precision requirements,large board size and uneven MC distribution of wood.(4)The estimated MC of the specimen is about 3%larger than the actual value,and the error can be reduced by using sharp cutting tools,reducing the drying temperature and use on-line weighing device for timely measurement.

关 键 词：木材干燥 含水率 含水率分布 含水率计算 显著性分析 

分 类 号：S781.71[农业科学—木材科学与技术]