共查询到19条相似文献,搜索用时 156 毫秒
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为了从南方寻找适用于压缩木梭坯的新树种,以减轻压缩木梭坯只能用东北色木的压力,近来从贵州台江纺织器材厂搞来了五种新树种的坯料,进行了压缩工艺试验和物理力学性能的测定,发现其中有一种树种的木质构造及物理力学强度,超过了东北色木。现将情况叙述如下。 相似文献
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影响压缩木含水率的主要环节是:定性毛坯含水,汽蒸吸湿,热压定型排水。分析对比了武汉、河南、济宁、北京、沈阳、陕西等纺器厂的压缩木工艺。认为压缩木含水率应随地区而异,北方以3~8%为宜。在工艺上要控制加热温度,改善汽蒸条件,热压定型的蒸汽表压应稳定在0.5MPa。 相似文献
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采集了福建各地40多种木材进行了木梭新材种的试验。试验材种包括针叶材和阔叶材的环孔材米槠、甜槠、苦槠、栲树、板栗等,其中有多种木材物理性能、力学性能均达到木梭标准。对针叶材与阔叶材的环孔材的心材与边材,压缩方向,脱脂处理等都作了分析。 相似文献
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压缩木干缩与湿胀直接影响木梭产品质量。对光皮桦自然木和压缩木的吸水性、湿胀性,不同压缩率与干缩系数的关系,压缩木容积重与干缩系数关系等进行了一系列试验。试验表明:压缩木的吸水性、湿胀性变化由大到小;压缩率越大干缩系数也越大;压缩木容积重越大干缩系数越小。 相似文献
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B. Belleville T. Stevanovic A. Cloutier A. Pizzi M. Prado S. Erakovic P. N. Diouf M. Royer 《Holz als Roh- und Werkstoff》2013,71(2):245-257
Thermochemical changes during wood-dowel welding were investigated in two Canadian hardwood species commonly used for indoor appearance applications: sugar maple (Acer saccharum) and yellow birch (Betula alleghaniensis). The original reference wood sample and the welded interface between two bonded wood pieces, a dowel and a substrate, were compared to explain differences in mechanical properties between species. Pyrolysis gas chromatography–mass spectrometry (Py-GC/MS), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS) were used. The gases emitted during wood welding were determined by Py-GC/MS and gas chromatography coupled with a thermal conductivity detector and a flame ionization detector (GC-TCD/FID). Results showed that thermal welding of birch and maple woods degrades hemicelluloses and affects lignin polymer through depolymerisation. Welding effectiveness is therefore directly associated with the properties of the original wood constituents, primarily lignin and carbohydrates. The lignin-related changes at the welded interface were greater for sugar maple than for yellow birch, corroborating mechanical property differences observed between the two species. The gases proportions were similar for both species and no harmful gases were detected in the smoke released during welding process. 相似文献
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挤压疏解作用对木片吸收性的影响 总被引:1,自引:0,他引:1
本文研究了挤压疏解作用对木片吸收性的影响.结果表明,原木片对1%NaOH溶液的吸收速度高于对苯的吸收速度,更高于对水的吸收速度,而且初始吸收速度很快, 1%NaOH溶液的1min吸收量可达到7min吸收量的85%,苯可达到80%,水可达到75%.杨木的吸收性明显好于桦木.挤压疏解作用可以显著改善木片对各种液体的吸收性,其中杨木对水、苯和1%NaOH溶液的吸收量分别为木片的6、4和5倍,而桦木分别为4、3和4倍.挤压疏解的次数增加,吸收效果明显改善,但挤压疏解次数超过2次以后,吸收能力增加的幅度减小. 相似文献
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介绍了当前广泛应用的备木生产线中原木剥皮、削片、木片筛选、过大木片再碎、木片贮存、树皮及木屑处理以及原木冲洗等系统的特点,通过分析不同剥皮鼓的喂料及卸料方式、不同削片机的喂料及卸料方式以及各种备木生产设备运行的情况,对备木设备的改进以及设备布置的方式提出了一些建议。 相似文献
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为探讨废弃纺织品作为原料在现代造纸工业中的应用,按照原料和颜色深浅把废弃纺织品分为4类:合成纤维(浅色)、纤维素纤维(浅色)、纤维素纤维(深色)、纯棉纤维(浅色),将原料经粉碎工序加工成散纤维,分别与木浆配抄成手抄纸,分析了配抄纸的各项物理性能。结果表明,手抄纸具有优异的透气性能,透气度为91.70~100.00μm/(Pa·s),是木浆(对比样)手抄纸的9.6~10.44倍;力学性能低于木浆手抄纸,是木浆手抄纸的27.8%~55.6%;废弃纺织纤维与木浆配抄纸的白度与纺织品纤维原来的颜色相关。 相似文献
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Properties of laminated veneer lumber (LVL) made with low density hardwood species: effect of the pressure
duration 总被引:1,自引:1,他引:0
Cross-linked polyvinyl acetate (PVAc) adhesive and thin veneers of three low density wood species, namely silver maple, yellow poplar and aspen, were used to produce LVL engineered wood products using different press durations. Density, water absorption, thickness swelling, flexural strength and surface hardness were evaluated. Internal bond strength, tensile shear and block shear strengths were tested in dry, accelerated (boiling and dry) and cyclic (wet and dry) conditions. LVL made using cross-linked polyvinyl acetate and silver maple with a platen temperature of 38 °C for 5 minutes exhibited the best properties. LVL of silver maple veneers showed improved properties as compared to yellow poplar and aspen. Silver maple can be used suitably in laminated veneer flooring. 相似文献
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介绍了三层结构实木复合地板的特点,并从发展仿古三层结构实木复合地板、速生材压密表板、LVL表板、科技木表板、竹材表板、多树种表板等方面阐述了三层结构实木复合地板表板发展的趋向。 相似文献
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阔叶木APMP制浆生产实践 总被引:2,自引:3,他引:2
介绍了以杨木、桦木制备APMP及配抄低定量胶印新闻纸的生产情况和存在的问题。总结了木材种类、质量、化学药品用量对纸浆质量的影响及生产时的污染状况。 相似文献