共查询到20条相似文献,搜索用时 15 毫秒
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通过NS(一种化学药剂)改性落叶松材和素材在相同干燥基准下干燥速度和干燥质量的对比试验,研究了Ns改性对落叶松材干燥性能的影响。结果表明:NS改性可显著改善落叶松材的干燥性能,40mm厚板材平均干燥速度可提高48%以上,各项干燥质量指标均高于国家二级标准,完全可满足家具等生产的需要。 相似文献
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云南铁杉干燥过程中变色的控制 总被引:6,自引:0,他引:6
云南铁杉在干燥过程中的变色问题是困扰许多木业企业的一个技术难题。笔者通过近几年的研究和实践 ,从其木材组分入手 ,分析了在干燥过程中云南铁杉变色的原因 ,制定了减轻变色程度的干燥工艺措施 ,使铁杉干燥过程中的变色率降至 10 %以内 ,其质量达到国标规定相应的技术指标 相似文献
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通过对比性试验和研究,提出用汽蒸法替代蒸煮法处理俄罗斯产进口山毛榉的新工艺。采用此工艺干燥处理后 的山毛榉,颜色鲜艳,干燥周期短,开裂和变形小,适用于木材加工业的批量生产。 相似文献
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针对移行材和早材皱缩等主要气干缺陷,拟定出赤桉半干材的干燥工艺,窑干前进行回复皱缩和减小表面硬化的汽蒸处理,窑干至目标含水率时进行终了调湿处理.结果表明:汽蒸预处理可以有效地回复皱缩材和显著地减小表面硬化;5 d内将试材的平均含水率25.61%下降到11.72%;3 h的汽蒸处理和24 h的湿空气处理均可有效地减小含水率梯度和残余塑性变定,但后者效果更佳;板材干燥质量达到国家标准二级质量的要求. 相似文献
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根据俄罗斯产云杉木材的特点,采用常规室干的方法,对其40 mm厚锯材的快速干燥工艺进行初步探讨,并提出可供木材干燥生产参考的干燥基准,有效地提高木材干燥效率并防止变色. 相似文献
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以40 mm厚的辐射松(Pinus radiata)和人工林杉木(Cunninghamia lanceolat)锯材为对象,研究高温干燥过程中干燥温度和锯材含水率对萜烯类产物释放浓度的影响,并与辐射松常规干燥中的萜烯类释放浓度作比较。高温和常规干燥过程中采抽气样次数均为5次,抽气速度为1.0 L/min,采样时间为30 min,采用Tenax管收集干燥过程中萜烯类产物,用气相色谱仪分析其成分及浓度。结果表明:高温干燥辐射松萜烯类释放浓度高于常规干燥辐射松与高温干燥人工林杉木,但萜烯类挥发物的组分有所差别。常规干燥辐射松锯材萜烯类释放浓度对环境是安全的,然而在高温干燥过程中,尤其在干燥中后期,当萜烯类挥发物浓度大于1.5 mg/m3时,对辐射松和人工林杉木释放萜烯类挥发物应采取回收措施,以确保对环境的安全。 相似文献
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李良 《内蒙古林业调查设计》2010,33(4)
文章采用百度试验法对金檀木材进行干燥特性研究,提出金檀家具用料板材的干燥基准,并进行了工艺试验研究。结果表明,金檀木材初期开裂为5级;内裂为2级;截面变形为3级,干燥速度为4级。初期开裂较严重,干燥速度慢,故金檀为难干燥木材。采用给出的干燥工艺,42 mm厚铁线子地板坯料从初含水率30.66%干燥到12.8%的干燥周期为43d,干燥质量满足家具用料的加工要求。 相似文献
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ZHOU Yongdong LI XiaolingResearch Institute of Wood Industry Chinese Academv of Forestry Beiijing P.R.China 《中国林业科技(英文版)》2004,3(4):72-75
The drying characteristic was studied for plantation wood of Chinese fir and poplar, which are typical plantation wood of southern and northern part of China, respectively. Through 100-degree-method the drying characteristic and basic drying condition were gotten, then drying schedule was developed for practical drying, the results showed that the drying schedule is suitable for Chinese fir and poplar plantation lumber, but shrinkage is large. The recommendation was made that enough dead weight is needed to decrease shrinkage in drying process. The drying quality of the two species of lumber is good in conventional drying method. 相似文献
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This study was conducted to develop analytical models for the prediction of drying stresses and defomations in lumber. Both one- and two-dimensional analytical models were developed with two assumptions: the visco-elastic creep could be neglected, and the diffusion coefficient is constant with moisture changes. The method developed in this study showed that the drying stress of lumber with symmetric moisture profile could be approximately predicted using one-dimensional (1D) and two-dimensional (2D) models. In the case of the 1D model, drying deformations could be determined rather easy and the drying stress can even be predicted by hand calculation. The results of this study might be used for lumber with an asymmetric moisture profile. In order to predict more accurately drying stress and deformation across overall moisture changes, however, this procedure should be incorporated with the other moisture transport models and might be extended to a 3D model. 相似文献
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木材干燥工艺温度控制系统目前多采用传统的PID控制方法.本文介绍了模糊控制在木材干燥工艺中的应用.仿真结果表明这种控制方法比传统的PID控制系统精度高、速度快,具有一定的应用价值. 相似文献
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《Wood material science & engineering》2013,8(4):190-195
Abstract A Lumber Quality Model developed to predict lumber grade after drying was applied and validated in industry. The model was calibrated with a 198-piece lumber package that was dried at a local sawmill in British Columbia, Canada, and 30 sawmill grade reports were recorded from 2008 to 2010. The calibrated model was then used to predict the target moisture content that would result in the maximum lumber value. It was predicted that lumber value should increase by approximately 17 CAD (Canadian dollars) m?3 if the target moisture content were reduced from the historic 17% to an optimum of approximate 13%. The sawmill implemented the recommendations and the predictions were validated with another seven industrial drying runs. 相似文献