Development of Continuous Press Systems for Compressed Wood

压缩木材连续压机系统的开发

• 批准号: 11556033
• 负责人: INOUE Masafumi
• 金额: $ 8.7万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11556033/
• 关键词: Wood; Transverse compression; Plastic Deformation; Roller press; Arigatoring crack; Surface check; Mechanical properties; Liquid impregnation; 破壊; 圧入角; ワニロ破壊; 縦割れ; 幅反り; 圧縮; 高周波加熱; 水蒸気前処理; 変形固定; 圧力; トルク

(1) A roller press machine was newly designed and manufactured on the basis of the results from transverse compression test of wood. The press is equipped with a pair of replaceable metal rollers with a servomotor (4.4kW). The size of rollers are 200, 300, 400 mm (diameter) by 300 mm (width). The roll temperature is controllable up to 220℃ by using cartridge heater (14.4kW). The maximum load, torque and rotation speed are 40kN, 5000 kNm and 15 rpm, respectively. The roller gap is controllable from 0 to 150 mm by shifting the position of upper roller. The load cells (5000 kgf) are set under the axle box of lower roller.(2) We found the several defects of compressed wood. Some of them occurred by roller pressing only. The specific phenomena resulting from roller pressing are alligatoring crack, surface check and shear cracks. Besides, longitudinal split, cup and crook are evident on visual check.(3) These failures correlate to contact angle θ and surface strain ε・θ is calculated by the equation [cos θ = 1-(T-H)/φ] with thickness of wood sample (T), compression rate (T-H)/T, and roll diameter (φ), εby [ε =μθ/180 sin θ-1]. Bending properties of dry and wet Sugi dramatically decreased when contact angle exceeded 8 and 9.5° , respectively.(4) We have proposed the novel liquid impregnation method using roller-compression of green timber in the treatment vessel with solution. In this process, free water inside the green timber is removed from the cell cavities in the treatment vessel and concurrently replaced with treatment solution. This technique seems applicable to chemical treatment of timber without drying before treatment, and resultantly a reliable uniform liquid impregnation and reduction in production costs are achievable.

(1)根据木材横向压缩试验的结果，设计制造了一种新的辊压机。压力机配有一对可更换的金属辊和一个伺服电机（4.4kW）。滚筒的尺寸为200、300、400毫米（直径）× 300毫米（宽度）。采用14.4kW的筒式加热器，可控制辊温至220℃。最大负载40kN，最大扭矩5000knm，最大转速15rpm。通过移动上辊位置，可在0 ~ 150mm范围内控制辊隙。负载传感器（5000kgf）设置在下压路机轴箱下。我们发现了压缩木材的几个缺陷。其中一些只发生在辊压过程中。辊压产生的具体现象有鳄鱼形裂纹、表面裂纹和剪切裂纹。此外，纵裂、杯形和弯形在目测中也很明显。(3)这些破坏与接触角θ和表面应变ε·θ的关系由[cos θ = 1-(T- h)/φ]与木样厚度(T)、压缩率(T- h)/T、轧辊直径(φ) ε = [ε =μθ/180 sin θ-1]的关系式计算。当接触角超过8°和9.5°时，干杉木和湿杉木的弯曲性能急剧下降。(4)提出了用溶液对生材在处理容器中进行辊压的新型液体浸渍方法。在这个过程中，绿色木材内部的自由水从处理容器中的细胞腔中除去，同时用处理溶液代替。该技术似乎适用于木材的化学处理，在处理前不需要干燥，因此可以实现可靠的均匀液体浸渍和降低生产成本。