木材锯切表面粗糙度二维分析与三维分析对比

使用传统的二维轮廓测定方法,测量木材锯切表面粗糙度准确度不高。利用三维表面轮廓成像技术测定木材锯切表面粗糙度,可获得较为准确的检测值和更真实的锯切表面微观形貌。     

生物质板材表面热压塑化平整加工技术的发展

介绍了国内外生物质板材表面热压塑化平整加工技术和装备的发展现状，提出了我国研发热压塑化平整加工工艺和装备的技术路线。该加工技术可以平整人造板和实木板材的表面和侧面，改善其表面粗糙度并可提高硬度，有利于环境保护、降低成本、缩短工期，完全可以替代砂光工序。     

德国的木材刨切技术

德国的木材刨切技术由德国ＬｉｎｃｋＨｏｌｚｖｅｒａｒｈｅｉｔｕｎｙｓｔｅｃｈ－ｎｉｋ公司提供的木材刨切技术，可取代锯切方法生产薄板材，该项技术主要优点在于生产工艺灵活性大及原料利用率较高。传统锯切法生产的板材，由于存在锯路损失和锯切表面不光滑、精度低...     

原条造材应注意的几个问题

原条造材,就是把采伐下来的伐倒木,经过打枝集运到料场后,根据国家木材标准锯截成不同长度的原木。在木材生产过程中,造材是一道不容忽视的重要工序。它不仅是把原条锯截成不同规格的原木,更重要的是与合理地利用木材资源,保证完成材种计划,提高产品质量,增加等内材,实现材尽其用,有着密切联系。正确地认识和搞好这道工序,对于提高木材利用率,降低生产成本,增加企业经济收入,起到十分重要的作用。但是,由于我省林区木材生产条件差,造材工序都在山场集     

氧乙炔火焰修锯设备及其应用

在木材加工行业采用氧乙炔火焰修锯,改变了传统的修锯方法,革新了修锯技术。本文重点介绍了氧乙炔火焰修锯设备的结构特点、工怍过程及主要工艺参数。     

木材加工超薄圆锯片基体结构对其稳定性的影响

木材加工超薄圆锯片的稳定性是影响锯切质量的重要因素之一,圆锯片的稳定性会随着锯身厚度的减小而降低。在切削木材过程中产生大量切削热会使锯身发生热形变,进而导致锯片稳定性降低。提高圆锯片切削稳定性传统的方法主要在生产工艺上通过对锯身施加预应力,抵消切削热对锯身形变的影响。本文通过改变锯身的基体结构,对不同基体材料的木工圆锯片进行基体几何处理,使其能够在切削木材过程中抵消热应力,从而提高切削稳定性。     

木材锯切技术的发展

简述木材锯切技术所经历的手工期、简单机械期、近代期和现代期及其特点,对各种木材锯切技术进行了分析,结论是零锯料角木工锯子技术整体性能较好,可以实现高质量、高效率、高效益锯切木材.     

锯切表面粗糙度的综合评价

为了提高木材锯切表面的加工质量，探讨了微观不平度十点高度Rz在评价锯切表面粗糙度方面的可行性，并提出综合使用Rz和Ry两个参数来评价锯切表面粗糙度更加合理。     

市场信息

第二代人造木材市场前景好。二代人造水村目前已配制成功并开始推广。它的主要成份是以锯未，刨花、玉米秸秆，各种农作物秸秆等为主料．经科学配制而成，可取代现有木材．三、五台板．中高密度板，纤维板，刨花板，用于家具、娱乐器具的制作及车船壁面、墙面、地面、房顶等处装饰。产品具有表面平整，光亮照人、质地坚硬、厚薄可调，防水防火绝缘，耐腐蚀．不易老化，不变形，可锯、钉、刨、柏等特点，该产品表面可形成几十种木纹图案，具有深远的推广价值。＠美国将大量进D木材、美国在今后数年中，将加大木材进口量。由于环境保护因素的…     

框锯结构方案探讨

框锯由于加工损失较大,不适于锯割劣质木材等缺点曾被我国淘汰.但因其加工精度高于其他制材设备,近年来,又重新受到重视,不少单位正在进行框锯的研制工作. 我国目前使用的框锯总数不超过20台,绝大多数是四、五十年代的进口产品,性能低劣,结构落后,已陈旧不堪,远远不能满足生产需要.国外现代框锯虽然性能先进,但结构复杂,成本高昂,在很多方面不适合我国生产需要.本文参照国外框锯的构造,并根据我国的制材条件提出了框锯结构方案,与框锯研制者共同探讨. 一、框锯主要参数的确定确定框锯参数的主要依据是:应使木材表面的加工质量和生产率满足一定的要求. 木材表面加工质量主要取决于每齿进给量(即平均切屑厚度)的大小.根据对木材     

Prediction of the surface roughness of wood for machining

The surface quality of solid wood is very important for its effective response in manufacturing processes. The effects of feed rate, cutting depth and rake angle on surface roughness and power consumption were investigated and modeled. Neuro-fuzzy methodology was applied and shown that it could be useful, reliable and an effective tool for modeling the surface roughness of wood. Thus, the results of the present research can be successfully applied in the wood industry to reduce time, energy and high experimental costs.     

Factors of affecting the spring back of compressed Paulownia wood

In order to increase its hardness and gravity as well as dimension stability, the technology of hotcompressing on Paulownia wood was studied. The main factors of affecting the spring back of the compressed Paulownia samples were discussed. It was discovered that every factor in the experiment had obvious effects on wood hardness and dimension stability of compressed wood. When the MC (Moisture Content) of experimental specimens was 13.89%, it was useful to spray water on the surface of samples before hot pressing. The best resuit was the recovery of compression set could decrease from 90.69% of untreated wood to 45.51% of soaking specimens into PF (Phenol Formaldehyde) water solution. The hot pressing time was 8 min at 190 ℃.     

Factors of affecting the spring back of compressedPaulownia wood

In order to increase its hardness and gravity as well as dimension stability, the technology of hot-compressing onPaulownia wood was studied. The main factors of affecting the spring back of the compressedPaulownia samples were discussed. It was discovered that every factor in the experiment had obvious effects on wood hardness and dimension stability of compressed wood. When the MC (Moisture Content) of experimental specimens was 13.89%, it was useful to spray water on the surface of samples before hot pressing. The best result was the recovery of compression set could decrease from 90.69% of untreated wood to 45.51% of soaking specimens into PF (Phenol Formaldehyde) water solution. The hot pressing time was 8 min at 190°C. Responsible editor: Zhu Hong     

Wood friction characteristics during exposure to high pressure: influence of wood/metal tool surface finishing conditions

Friction that arises during processing for the deformation of wood under relatively high pressure levels (ca. >1 MPa) is an important factor to be taken into account when wood is processed. However, few studies on such friction have been published. The present study was undertaken to evaluate the influence of surface finishing conditions on the nominal friction coefficient (μ) of the wood and metal tool surfaces. Sticking friction was likely to arise on a relatively coarse metal surface, and the type of metal tool surface finishing was found to have large impact on the friction mechanism. The friction characteristics during exposure to high pressure seem to be affected not only by the interface contact characteristics, but also by the deformation characteristics of wood during compressive load or measurement. The value of μ on water-saturated wood was equal or higher than that on dry wood, which suggests that the contact characteristics between these two types of wood are significantly different. The water content in wood was shown to affect both the interface contact and deformation characteristics of wood. The value of μ was not significantly affected by the wood surface finishing conditions; however, changes in μ during sliding differed slightly, depending on the finishing conditions.     

碳水化合物作添加剂制木质刨花板的研究 Ⅱ糖的作用机理

本研究通过对以糖蜜为助粘剂制造的木质刨花板中木材糖基组成和糖蜜中游离单糖在热压条件下的转化情况和含量变化的研究,解释了糖在木质刨花板中产生胶合作用的方式。结果表明,在热压过程中木材表面化学活性增加,部分纤维素和半纤维素水解。这些水解单糖与糖蜜中的游离单糖均能转化成糠醛,与活化了的木素发生键合作用,生成树脂类化合物,从而达到胶合的目的。经红外光谱测定,在热压后,刨花表面化学基团发生变化,亲水性羟基官能团减少,僧水性羰基官能团增加,说明了糖蜜压制的刨花板具有良好耐水性的原因。这一结论为开发人造板的“无胶”技术提供依据。     

基于分形维木材表面粗糙度的研究

应用分形维对木材表面粗糙度特征进行研究。首先，对Sarkar和Chaudhuri提出的分形维计算方法做了改进：其次，以60个树种为研究对象，提取和分析木材表面的分形维数。得出结论：分形维数能够反映木材表面的粗糙程度，可作为木材表面粗糙度的一种度量？     

木纤维—合成纤维复合的研究

通过对不同复合条件下压制的木纤维－合成纤维复合材料的研究，探讨了木纤维的化学改性和胶粘剂的改性在木纤维－－合成纤维复3合过程中的作用，研究表明，木纤维能和顺丁烯二酸酐和丁二酸酐进行酯化反应，从而降低木纤维的表面极性，化学改性后的木纤维能与合成纤维进行良好的复合，改性胶粘剂对表面不同极性的木纤维和合成纤维都有良好的附着作用，可有效地改善木纤维与合成纤维的复合性能。     

Press-induced lateral resin flow and its effects on resin area coverage on composite wood strands

Resin flow during hot pressing affects resin area coverage on the wood surface and penetration into the wood substrate, and further affects the bonding performance of wood composite products. This study explored the flowing characteristics of a phenolic resin on a wood strand surface and its effects on resin area coverage under various conditions. The results indicated that the heat and pressure of hot pressing made the resin flow and significantly increased the resin area coverage. Three factors, i.e., compaction ratio of wood strands, pressing temperature, size and thickness of resin spots, had effects on resin flow and resin area coverage. The resin area coverage after hot pressing increased with compaction ratio and reached the optimum value of compaction ratios ranging from 1.25 to 1.30. The pressing temperature, however, gave very similar effects on resin flow and resin area coverage when the pressing temperature was far above the temperature at which the resin begins to flow. The small resin spots generally showed a higher increase in resin area coverage than the big spots. However, this effect was somehow masked by the effect of spot thickness, which demonstrated a more significant effect on the resin flow and resin area coverage.     

数字图像相关技术及其在木材科学研究中的应用

数字图像相关方法(DIC)作为一种先进的光学形变(位移和应变)检测方法, 已逐渐成为木材科学领域中一种重要的测试手段。文中概括了DIC的特点与基本原理; 综述了其在木材科学领域中的应用, 主要包括力学性能检测、木材干燥形变测量及其他木质基材料等的相关性能研究; 最后, 对其在木材科学领域研究中遇到的机遇与挑战进行了展望。