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微米长薄片木纤维切削加工功率的理论计算方法与效益分析 总被引：6，自引：2，他引：6
对传统纤维加工的功耗进行分析,将细胞学、超精加工理论、纤维学等一系列现代分析手段运用到木纤维的形成过程中,提出微米长薄片木纤维切削的概念,从而将微米长薄片木纤维的研究上升到微观结构,并通过对纤维形状的产生和切削力变化的分析,解释传统木纤维加工消耗的能源高、产生纤维质量差的本质原因.示例对微米长薄片木纤维的加工功率进行计算,将其与传统加工方法的功率进行对比,得出结论:以微米级机械法加工木纤维耗能远远低于热磨法,且可以加工出质量较高的微米级长丝木纤维. 相似文献
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回顾了纤维形成方法及纤维板发展历程,分析了传统纤维板形成理论的缺陷,介绍了微米长纤维高强度低密度人造板(简称MLFB)的形成理论,分析并阐述了该板种的优势,论述了开发研制这一新板种的可行性。 相似文献
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提出了微米级长薄片状木纤维高强度人造板的组成单元——微米级长薄片木纤维切削功率的计算公式,并根据实验数据进行功率计算。结果显示,微米级长薄片木纤维切削功率较低。 相似文献
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木材节约的重要途径:城市废弃木材利用 总被引：3，自引：0，他引：3
根据我国木材资源和城市废弃木材状况,阐述利用城市废弃木材的意义、重要性和可行性.从我国宏观经济发展政策、人造板原料市场需求、经济效益,到微观废弃木材收购、加工设备和技术开发、废弃木材利用应采取的措施等提出建议. 相似文献
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为解决传统热磨法加工微米薄木片及木纤维中高能耗、工序复杂、加工成本高的缺点,现改变加工方法,采用顺纹纵向刨切木材的方式,研发了数控微米刨切试验台。试验台主要由机架、纵向进给机构总成、工件夹具、控制面板、刨切机构总成、升降机构总成和限位机构组成,可对宽度为50 mm,长度为300～600 mm,高度为20～90 mm的木材工件进行纵向进给、切削量进给和刨切作业。笔者对试验台整机以及各机构进行设计,并通过ANSYSY对刀具进行强度校核。通过试验,确定刨切机构切削角δ取45°,刀刃伸出量h取0.05 mm,刀门宽度d取0.2 mm,刨得的木片平均厚度为18.7μm,最薄为15μm。最后通过显微镜观察发现经过刨切后的刀刃部分出现磨损,可通过表面改性提高刀具的耐磨性。 相似文献
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通过建立单个木纤维细胞结构形状的数学方程，分析确定定向微米木纤维加工技术形成的方法，同时讨论了实现微米木纤维细胞劈裂的条件。本文提出的理论将为人造板加工手段深入到细胞结构水平提供一种新的理论和方法，其产品具有广阔的工业化前景。 相似文献
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After reunification in 1990, Germany’s forest cluster developed anew and employment in the wood-based industries differentiated
very quickly. With more than 900,000 employees, it is now considered one of the most important industrial sectors in the country.
This paper analysed general trends in the development of employment of wood-based industries in the German forest cluster
between 1999 and 2006. Shift-share analysis was considered to be the most appropriate way to determine regional differences
in the subsection DD/20 ‘Manufacture of wood and wood products’ of the code “Classification of Economic Activities in the
European Community, Revision 1.1” (NACE): the sawmill industry, the wood-based panel industry, the wood construction industry,
the wood-based packaging industry, and the miscellaneous wood products industry. This method decomposed the change of employment
into three different components that are due to that change: national trends, (industrial) sectoral trends, and regional conditions.
Employment in the selected wood-based industries showed a significantly larger decrease than overall trends in both the producing
industries and the whole economy of Germany: a continual loss of employees could be observed over the time period, affecting
almost all of the selected wood-based industries. However, federal states in western and eastern Germany experienced divergent
trends between 1999 and 2006, as different absolute and relative regional share components indicated in the shift-share analysis.
This method allows of identifying regional disparities and characterising regions with positive (mainly eastern federal states)
and negative (mainly western federal states) rates of employment growth. The research suggests that positive employment trends
in eastern Germany’s wood-based industries can mainly be attributed to regional factors such as comparatively higher subsidies
for new investments, lower labour costs, lower land values or infrastructural peculiarities.
相似文献
| Dajana KleinEmail: |
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微米木纤维模压制品握钉力计算理论 总被引：4，自引：0，他引：4
分析微米木纤维模压制品握钉力计算的重要性,提出其握钉力力学分析的基本假设,建立其握钉力计算的力学模型,推导螺纹牙受力的分布函数.应用本文提出的理论,可以根据微米木纤维模压制品的刚度和螺纹的几何参数定量计算螺纹牙受力分布,进而计算其握钉力,为微米木纤维模压制品握钉力计算提供重要理论依据. 相似文献
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浅议我国从人造板大国迈向人造板强国的途径 总被引：7，自引：0，他引：7
人造板是木材工业中技术最密集、用途最广泛、最具发展潜力的产品,是衡量一个国家木材工业、木材科技水平和综合国力的重要标志。改革开放20多年后的今天,中国人造板已进入大规模工业化生产,成为有自己特色和优势的新型产业,步入世界人造板大国行列。但是,与世界人造板强国相比,中国人造板生产还存在明显的差距,表现在企业规模偏小、技术水平与国外差距较大、扩大再生产投入资金不足和技术开发研究重视不够等。为使中国迈向人造板生产强国,必须制订好中长期发展规划,在优化人造板的产品结构,实现人造板生产过程自动化,大力开发有自主知识产权的创新技术和产品,开发废旧木材和废弃人造板资源的再利用技术,加强人造板工业的标准化管理和产品质量监督检验,重视人造板工业的人才培养等多方面进行努力。 相似文献
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本文综述了目前国外木质碎料干燥技术的现状.分别介绍了主要的燃料种类和能源转换方式、在人造板工业上常被应用的典型干燥装置、近年来在干燥工艺和节能技术方面的进展,以及干燥设备的安全卫生保护. 相似文献
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微米木纤维形成MFB的初探 总被引：15，自引：0，他引：15
提出了一种新板种MFB的制备方法。MFB由特殊的构成单元组成,该构成单元系根据细胞破碎理论采用微切削工艺制得,其厚度达到微米级水平。根据其方法在实验室制得的MFB样品的弹性模量达5171MPa,握钉力达1933N。MFB具有很多优点:具有木本色、美感、保温、绿色消费、寿命高、没有节子一类缺陷、防止变形等,所以可得到广泛的应用,其发展前景良好。笔者认为,MFB板种的提出是对人造板的发展做出了贡献。 相似文献
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Ashraful Alam Antti Kilpeläinen Seppo Kellomäki 《European Journal of Forest Research》2012,131(3):655-667
An ecosystem model (Sima) was utilised to investigate the impact of forest management (by changing both the initial stand
density and basal area thinning thresholds from current recommendations) on energy wood production (at energy wood thinning
and final felling) and management-related carbon dioxide (CO2) emissions for the energy wood production in Finnish boreal conditions (62°39′ N, 29°37′ E). The simultaneous effects of
energy wood, timber and C stocks in the forest ecosystem (live and dead biomass) were also assessed. The analyses were carried
out at stand level during a rotation period of 80 years for Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst.) growing in different fertility sites. Generally, the results showed that decreased basal area thinning thresholds,
compared with current thinning, reduced energy wood (logging residues) and timber production, as well as carbon stocks in
the forest ecosystem. Conversely, increased thinning thresholds increased energy wood production (ca. 1–27%) at both energy
wood thinning and final felling and reduced CO2 emissions (ca. 2–6%) related to the production chain (e.g. management operations), depending on the thinning threshold levels,
initial stand density, species and site. Increased thinning thresholds also enhanced timber production and carbon stocks in
the forest ecosystem. Additionally, increased initial stand density enhanced energy wood production for energy wood thinning
for both species, but this reduced energy wood production at final felling for Scots pine and Norway spruce. This study concluded
that increases in both initial stand density and thinning thresholds, compared with the current level, could be useful in
energy wood, timber and carbon stocks enhancement, as well as reducing management-related CO2 emissions for energy wood production. Only 2.4–3.3% of input of the produced energy (energy wood) was required during the
whole production chain, depending on the management regime, species and sites. However, a comprehensive substitution analysis
of wood-based energy, in respect to environmental benefits, would also require the inclusion of CO2 emissions related to ecosystem processes (e.g. decomposition). 相似文献
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绿色生态、节能环保型人造板机械开发方向 总被引：2，自引：0，他引：2
绿色生态机床与节能环保设备是现代机械发展的趋势。对绿色生态与节能环保型人造板机械开发方向进行了探讨,指出绿色生态人造板机械由再生材料制造,其质量和体积由于使用再生材料可减少50％以上,通过减轻移动部件质量使功率消耗减少30％～40％,节能减排,废弃物少,报废后可回收。论述了我国人造板机械行业节能减排的总体措施与方向。 相似文献
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为促进人造板产业转型升级和科学发展,国内规划建设了一批具有鲜明特色的人造板产业园区。为克服人造板生产对环境造成的一定影响,采取完善的环境保护策略,配套完整的环保设施显得尤为重要。介绍了人造板产业园区定位,阐述了人造板生产对于环境的影响,包括废水、噪声、废气等污染,基于此,提出相应环境保护策略,为人造板产业园区实现绿色环保生产提供借鉴。 相似文献