【作者】 傅万四；

【导师】 刘一星；

【作者基本信息】 东北林业大学 ， 木材科学与技术， 2007， 博士

【摘要】 在科技部国际科技合作重点项目“竹质OSB削片技术与设备研究”和国家林业局“948”项目“竹材OSB刨片关键技术引进”的支持下，针对竹质OSB削片技术及相应的工艺学问题开展了系列的研究工作。1．阐述了我国竹材资源的优势及竹质定向刨花板(BOSB)的发展前景，分析并提出了制造BOSB的技术难点，指出竹材削片技术是亟待解决的关键技术问题。对应用竹材制造BOSB进行了调查性研究，在此基础上，进一步分析了用楠竹制造BOSB的可行性和优越性。分析结果表明应用优势资源的楠竹制造BOSB发展前景广阔。2．对竹材切削方式的研究结果表明：(1)按竹材3剖面方向，竹材切削方式可分为横向切削、纵向切削及端向切削3类，可细分为横Ⅰ型切屑、横Ⅱ型切屑、纵Ⅰ型切屑、纵Ⅱ型切屑、端Ⅰ型切屑、端Ⅱ型切屑6种类型。(2)竹材的切削质量主要受竹材密度、竹材含水率、切削厚度、不同切削面等因素的影响。(3)切削力主要受受竹材物理性质及主要切削参数的影响。3．以湖南楠竹为基材制造BOSB，研究了不同竹刨花形态参数对BOSB性能指标的影响，通过分析得出：(1)在设计的试验范围内，竹刨花的BOSB的性能指标均能达到中国林业行业标准的要求，但仍体现出不同厚度、长度尺寸的竹刨花形态参数对BOSB性能的影响；(2)当竹刨花尺寸为长度110～120mm、厚度0.6～0.8mm时，所制作的BOSB的性能指标最优。4．研究了热压温度、热压压力及热压时间等热压工艺参数对BOSB性能指标的影响，通过分析得出：(1)当热压温度为160℃时试板的性能指标最好，温度过高或过低均会使BOSB板材性能指标呈一定程度的下降；(2)当热压压力较低(2.1、2.3MPa)时，BOSB力学性能指标均较差；随热压压力的增加，BOSB板材力学性能指标明显提高，但板材密度也随之提高，致使板材原料消耗增加，成本上升。(3)当热压时间为70s／mm时，BOSB的各项性能指标均为最优。5．探讨了胶黏剂施胶量及相应工艺条件对BOSB性能的影响，同时，采用扫描电子显微镜(SESM)、傅里叶变换红外光谱仪(FTIR)对竹质刨花与酚醛树脂胶黏剂的界面以及胶黏剂的分布状态进行了分析。采用酚醛树脂胶黏剂试制BOSB的优化工艺条件为：施胶量：竹刨花质量的6％-8％(固体)施胶方式：喷胶刨花规格：长×宽×厚=110～120mm×9～15mm×0.6～0.8mm热压温度：160℃热压压力：2.5MPa热压时间：70s／mm采用水性异氰酸酯胶黏剂试制BOSB的优化工艺条件：刨花含水率：10％施胶量：4.5％交联剂主剂比：15∶85施胶方式：喷胶刨花规格：长×宽×厚=110～120mm×9～15mm×0.6～0.8mm热压温度：160℃热压压力：2.5MPa热压时间：40s／mm6．BOSB削片机方案设计。主要探讨制作竹材OSB加工工序相关问题，分析了影响竹材削片质量和产量的相关因素。对主要设备和设施进行了设计和分析，主要结果如下：(1)为了提高竹材的综合利用价值，优化生产工艺，将毛竹进行定段分级，利用次、小、梢竹材制造BOSB；(2)预处理设备是保证竹材定向削片的关键环节之一，包括竹材截段分级、纵向破竹(开片)、去内节(内隔)、定向排列组坯设备；(3)为实现竹材毛坯自动化定位排列，设计了定向排列自动识别与纠正系统，用于生产线中实时检测，及时调整毛坯正反位置，实现相同方向依次自动排列；(4)竹材定向削片技术的主要难点为：①当竹材定向排列送入竹材削片机后，如何将竹条夹紧定位，防止其在切削过程中出现较严重的松动、散乱，保持较理想的方向排列；②如何减少切削过程中竹刨花的破碎是重要技术难点，因竹材具有纤维间结合强度低的特性，在切削形成竹刨花过程中，一旦竹刨花受到横向力的作用或撞击，易出现碎裂现象。(5)设计了适合竹材制作BOSB的削片机方案。采用外环式横Ⅰ型削片原理，在切削过程中，通过刀环内浮动上压板、刀环内固定下压板和固定的弧形靠板的定位作用，实现定厚定长切削。(6)设计削片机刀片为2种：切削刀片(A型)和定长划线刀片(B型)。切削刀片的作用是将竹刨花从竹毛坯上切下，但在竹刨花被切下之前已被定长划线刀片在竹材表面划出一定深度的槽沟，切断竹材纤维，使被切削下的竹刨花自然形成分段状态。(7)削片机进料系统结构由进料槽板、压料辊、弹簧支座、可浮动砧铁、进料输送链毯、进料驱动辊、压辊弹簧等组成，以确保竹毛坯在加工中准确定位和牢固不动。更多还原

【Abstract】 Under the fanacial support of project "Flaking Technique and Equipment Development for Bamboo Oriented Strandsboard Manufacture" from Ministry of Science and Technology, and "948" project of "Oversea-introduced Key Flaking Technique of Bamboo Oriented Strandsboard" from the State Forestry Administration, this thesis has discussed series of critical problems on the flaking technique and manufacture of bamboo oriented strandsboard (BOSB).1. The advantage of bamboo resources in China and the future development of BOSB were addressed. The key technique problems in BOSB manufacture were also analyzed. It was pointed out that bamboo flaking technique is an urgent problem to be solved. Based on the investigation on BOSB manufacture, the thesis also explored the feasibility and advantage of BOSB manufacture using Moso bamboo (Phyllostachys heterocyclacv. Pubescen). The result indicated the bright development future in BOSB manufacture using Moso bamboo resources.2. The results of bamboo flaking method indicated that according to the three sawing directions, flaking modes were latitudinal-cut flaking, longitudinal-cut flaking and cross-cut flaking. It also could be divided into six detail modes: latitudinal-cutⅠ, latitudinal -cutⅡ, longitudinal -cutⅠ, longitudinal -cutⅡ, cross -cutⅠ, and cross -cutⅡ. The quality of bamboo flaking was mainly influenced by bamboo density, bamboo moisture content, flaking thickness, and flaking direction etc. The cutting force was mainly affected by bamboo mechanical properties and cutting parameters.3. This thesis discussed the manufacture of BOSB using Moso bamboo which planted in Hunan province. The effects of various dimensional parameters of bamboo strands on BOSB panel properties were investigated. The results showed that all the BOSB properties could meet the demand of Chinese Standard. The effects of strand thickness and length variation on BOSB properties were found. The optimum size of strands was 110～120mm in length and 0.6～0.8mm in thickness.4. The effects of hot pressing temperature, hot pressing pressure and hot pressing time on the properties of BOSB were discussed in the study. When the temperature reached to 160℃, the panel had the most superior properties. Otherwise, it would decline. BOSB showed inferior properties as the pressure was lower (e.g. 2.1 or 2.3 MPa). In the case of higher pressing pressure, the panel properties were improved with increasing panel density. However, this would cause an increasing of product cost and material consumption. When the hot pressing reached to 70s/mm, the BOSB property was the best.5. The influence of adhesive and respective technique condition were examined. The interface between bamboo strands and adhesive, and the resin distribution on bamboo strands were analyzed by using SESM, FTIR.The optimum technique of using water-solubility PF to manufacture BOSB:Resin content: 6%～8% based on oven-dried weight of bamboo strands (solid content)Blending method: SprayingStrand size: length×width×thickness=110～120mm×9～15mm×0.6～0.8mmHot pressing temperature: 160℃Hot pressing pressure: 2.5 MPaHot pressing time: 70s/mmThe optimum technique of using water-solubility PMDI to manufacture BOSB:Strand moisture content: 10%Resin content: 4.5%Ratio of main adhesive: coupling agent=15:85Blending method: SprayingStrand size: length×width×thickness=110～120mm×9～15mm×0.6～0.8mmHot pressing temperature: 160℃Hot pressing pressure: 2.5MPaHot pressing time: 40s/mm6. The schematic design of BOSB chipper was proposed. Several processing problems which affect the quality of flaking and capacity of BOSB were analyzed. It was the base for design the main production equipment and facilities. Results are as follows:(1) In order to increase the utilizition value of bamboo and to optimum the manufacture process, bamboo material should be cut into a certain length and be classified before using. Poor bamboo, small bamboo and the tip-parts of bamboo were also used to produce BOSB.(2) In the system of oriented flaking, the devices for pretreatment are the key, including block cutting and classification, longitudinal breaking, inner nodes eliminating, and oriented arrangement of bamboo pieces.(3) For the realization of auto-alignment, the auto-identifying and auto-correcting systems were designed to apply in real-time testing of production line. It could be used to adjust the right position of the surface and back of bamboo pieces, and to make sure their automatic arrangement in the same direction.(4) The key problem in oriented flaking was how to fix the position of bamboo pieces when it was forced to feed orderly into chipper to avoid their moving while flaking. Another problem was how to avoid strands smash. If strands were stricken in lateral, they were easily crushed due to the lower bonding strength between bamboo fibers.(5) The schematic design of strand chipper suitable for BOSB manufacture was proposed. According to the latitudinal-cutⅠ, flaking mechanism, of outer shell was choosen, and the flaking with fixed length and thickness could be possible by floating upper press plate, fixed low press plate and fixed curved position board in the blade ring.(6) Two types of chipper knives were designed, i.e., cutting knife (type A) and scoringknife (type B) for fixed length flaking. The function of cutting knife was to cut bamboo strands from a bamboo piece. Before they were cut off, a scoring-knife was used to precut a deep groove in the bamboo peice to section the strands.(7) The feeding system of chipper consist of feed plate, press roller, spring support, and float hammering iron, feed chain blanket, feed forced roll and press spring etc to keep bamboo pieces positioning and fixing.更多还原