共查询到19条相似文献,搜索用时 250 毫秒
1.
选择4种常用进口树种实木地板坯料和1种国产树种实木地板坯料,利用木材常规干燥试验机进行兼顾杀虫(D工艺)、灭菌(S工艺)的热湿平衡处理,检测分析其终含水率、厚度上的含水率偏差、残余应力、可见缺陷等指标变化。结果表明:地板坯料的质量在不同树种、同一批次内均存有差异。本研究中制定的D工艺(65℃/相对湿度73.8%~89.5%)、S工艺(75℃/相对湿度76.7%~91.2%)两个等级,可满足地板坯料杀虫、灭菌的加热技术要求,同时可降低地板坯料内和坯料间的最大含水率偏差,提高含水率均匀度,降低厚度上的含水率偏差,降低残余应力值,且对可见缺陷的影响不明显。热湿平衡处理坯料的质量符合LY/T 2058—2022《实木地板坯料》或GB/T 6491—2012《锯材干燥质量》中二级材的要求。 相似文献
2.
研究了枫香地板坯料的干燥上艺,并研究了三种不同原木径级对干燥速度和干燥质量的影响。试验中把枫木按原木径级分为30cm以上(A级),20~30cm(B级),小于20cm(C级),采用常规干燥工艺,对比三种研究对象的干燥速度和干燥质量。结果表明:枫香木材在含水率40%~50%阶段极易发生扭曲变形和开裂。采用文中的干燥工艺,25mm枫香地板坯料从初含水率79.57%到终含水率13.85%,干燥周期为376h(15.7d),干燥质量满足实木地板加工要求。枫香木材径级的大小对干燥速度没有显著影响,但C级干燥质量与A、B级有显著差异。 相似文献
3.
4.
5.
6.
管义榕 《林业机械与木工设备》2013,(9)
探讨了不同剖面密度分布的地板基材对模压地板主要物理力学性能的影响,揭示其变化规律。剖面密度分布不同的地板基材对模压地板成品的密度影响不大;剖面密度分布不同的地板基材,尤其是表层厚度对模压地板成品内结合强度、静曲强度、吸水厚度膨胀率的影响显著,表层厚度在2.0~2.4mm之间的地板基材压贴后的成品,其内结合强度下降的小,静曲强度下降大,吸水厚度膨胀率增加的多;表层厚度在1.2~1.5mm之间的地板基材压贴后的成品,其内结合强度下降大,静曲强度下降小,吸水厚度膨胀率增加少。 相似文献
7.
8.
1 概述 强化木地板为俗称,其学名为浸渍纸层压木质地板.它是以浸渍热固性氨基树脂的耐磨纸和木纹纸及平衡纸分别铺装在刨花板、中密度纤维板、高密度纤维板等人造板基材表面及背面,经热压、分片和加工企口而成的地板. 相似文献
9.
短周期工业材干燥过程中木材内部水分迁移特点的研究 总被引:8,自引:0,他引:8
研究了短周期共业材新伐材和气干材在干燥过程中木材厚度方向含水率分布和水分迁移特点,考察了干燥过程中介质温度变化及其对表层产中心层干燥速度的影响。研究表明,原木初含水率径向、从向存在变异、导致板材初含水率分布无规律。在非稳态干燥中,逐渐呈外低内高近似抛物线分布,直至平衡处理后,内外层含水率才接近一致。平均干燥速度随介质温度的提高而增加,不同干燥阶段介质温度的影响也不同,在相同的平衡含量水率条件下,提 相似文献
10.
史蔷 《林业机械与木工设备》2010,38(12)
以非洲圆盘豆地板坯料为试验材料,使用改造后的德国木材干燥机进行过热蒸汽热处理工艺试验.结果表明下述工艺切实可行:待处理试件含水率控制在10%;预热阶段将试件在80℃温度下保持2h;在高温干燥阶段升温至120℃并保持1h;然后迅速升温至热处理目标温度160~220℃范围内,热处理时间为2~8h,在试件热处理过程中进行喷蒸;热处理结束后,调整试件含水率至4%~6%,降温至60℃后出窑.经过该热处理可使地板材颜色加深及尺寸稳定性提高,进而提高地板产品质量. 相似文献
11.
单板/高密度纤维板(HDF)复合木地板结合了实木地板和浸渍纸层压木质地板的优点,是地板产业发展的新方向之一。文中以12mm厚HDF为基材、复合意杨单板,试制了"耐磨纸-单板-HDF基材-平衡纸"四层结构地板用复合板材。研究了不同单板厚度、胶黏剂种类(聚氨酯-PU,脲醛树脂-UF)及涂布量对板材翘曲度、吸水厚度膨胀率、内结合强度及机加工性能的影响。结果表明:1)单板与HDF复合制造木地板是可行的;2)复合木地板的翘曲度随单板厚度和施胶量的提高而递增,最高可达约0.6%;3)贴面采用聚氨酯胶黏剂,产品性能优于脲醛树脂胶合板材,但冷压周期偏长。推荐工艺条件为:单板1.2mm,PU或UF胶黏剂均可,涂布量控制在100g/m~2左右。 相似文献
12.
Steam conditioning of softwood boards after kiln drying is of critical importance for relief of residual drying stresses
and to improve distribution of final moisture content. The conditioning practice in New Zealand includes two steps: immediately
after high temperature (HT) drying the load is cooled until the core wood temperature is 75 to 90°C, and then the stack is
steam conditioned for a period of 1 to 4 hours depending on the lumber thickness and moisture content after drying. In this
work, experimental and theoretical studies were performed to better understand the conditioning process and to investigate
factors which influence its effectiveness. In the experiment, 50 mm thick Pinus radiata sapwood boards were first dried at 120/70°C for 11, 12, 13, 16 and 18 hours, respectively, to varying moisture contents,
and then cooled and steam conditioned for 1 hour. To assess the effectiveness of conditioning, moisture pick-up, moisture
gradient, and transverse residual drying stress (indicated by cup and strain) were measured. It was found that drying wood
to a low moisture content (below 6%) increased the conditioning effectiveness. A separate matched stack was conditioned for
4 hours after 13 hours drying which showed better results than 1 hour conditioning. A mathematical model for wood drying was
extended to include both the cooling and conditioning phases. The model was numerically solved to examine the wood temperature
and moisture content changes during the whole process of drying, cooling and final steam conditioning. Increase in wood temperature,
moisture pickup and moisture gradient during steam conditioning were predicted and validated by the experimental data. This
information is currently being used at the New Zealand Forest Research Institute in simulation of stress development and relief
for drying of Pinus radiata lumber.
Received 6 July 1998 相似文献
13.
14.
基于遗传算法的强化木地板表面缺陷的图像分割 总被引:1,自引:1,他引:0
强化木地板表面质量的图像检测技术在我国尚属空白.本文将遗传算法应用于强化木地板表面缺陷的图像分割,利用最大熵准则作为算法的适应度函数.实验表明,该算法可较准确地分割出强化木地板的表面缺陷,是一种有效的图像分割方法. 相似文献
15.
16.
随着地板扣型及外形的变化,国内从德国豪迈公司引进的强化复合地板生产线的核心设备双端铣刀轴配置8+8方式(刀轴顺序:预切刀、成型刀、精修刀、扣刀,即:4工位8轴)已不能满足生产需求,因此对双端铣刀轴配置进行了改进,对工位进行了相应调整(目前刀轴最高配置达到6工位12轴),在双端铣末端空位加设了两套刀轴,并采用专用倒角刀加工地板倒角,使地板产品的边缘直线度和粗糙度达到国家规定的质量标准。 相似文献
17.
18.
19.
If water stays on wood surfaces or is trapped in gaps, the wood is supplied with water for a long period of time and high local moisture contents are reached. This can lead to decay by rot fungi, and it is therefore important to avoid such water traps in order to limit the decay rate. This paper presents two methods: one for determination of duration of surface moisture on wood surfaces and one for determination of duration of water trapped in gaps in wood joints. Both these methods are based on electrical conductance measurements that are commonly used to measure moisture content of wood. Both sensor types consist of insulating tubing, electrically conductive adhesive and copper wire. The sensors monitor the presence of moisture on the actual material surface, and because of their small size, they do not influence the amount and duration of moisture that stays on the surface or in the gap. 相似文献