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排序方式: 共有38条查询结果,搜索用时 0 毫秒
1.
国产MJ3210小型木工跑车带锯机锯解正交试验分析   总被引:1,自引:0,他引:1  
采用正交试验设计法,对国产MJ3210小型木工跑车带锯机的锯解质量进行研究。通过实测马尾松锯材尺寸偏差、表面粗糙度等参数,得到其最佳的进料速度、锯解厚度和锯卡高度的组合方案。结果表明,该设备具有结构简单、出材率高、锯解精度高、质量好、成本低和生产效率高等优点。  相似文献   
2.
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。  相似文献   
3.
Abstract

Wood, as a natural material, has favourable properties in both technical and aesthetic aspects. Due to its inherent variability, production of high-quality sawn timber demands adequate control of log conversion, which is feasible with computed tomography (CT) log scanning. Existing appearance grading rules for sawn timber might not fully reflect people's visual perception of wood surfaces, and therefore, an alternative, more perception-oriented appearance classification could be beneficial. An appearance classification of sawn timber based on partial least squares discriminant analysis (PLS-DA) of knot-pattern variables was developed and tested. Knot-pattern variables derived from images of board faces were used in training PLS-DA models against an initial classification of the board faces previously established by aid of cluster analysis. Virtual board faces obtained from simulated breakdown of 57 CT-scanned Norway spruce logs were graded according to the developed classification. Visual assessment of the grading results indicated that the classification was largely consistent with human perception of board appearance. An initial estimation of the potential to optimize log rotation, based on CT data, for the established appearance grades was derived from the simulations. Considerable potential to increase the yield of a desired appearance grade, compared to conventional log positioning, was observed.  相似文献   
4.
分析、研究了制材工业中原木加工成板方材的3种下锯法与出材率的关系,并结合实际,对所得数学模型进行了计算机模拟验证,推知特定的原木在制材时所应采用的具体下锯法,对于木材的合理利用、提高出材率等均具有一定的指导意义。  相似文献   
5.
Abstract

A survey was conducted at nine sawmills in Japan to evaluate and compare the sawing of sugi (Cryptomeria japonica D. Don) logs of 30 cm and more in diameter. The purpose was fourfold: (1) to document sawing patterns appropriate to the large-diameter logs; (2) to examine the composition of wood components (structural, nonstructural, and fixtures) produced from those patterns; (3) to investigate log and product prices; and (4) to ascertain distances to the log supplier and product markets. Impetus for the study arose from a forecasted shift in the diameter distribution of plantation trees in Japan; from small and medium-sized logs to large-diameter logs. With an overabundance of large-diameter domestic logs forecasted within the next decade, the need to understand how to best utilize and effectively process the large-diameter resource is of utmost importance.  相似文献   
6.
Abstract

Growing markets for chopped firewood have created alternative uses for the by-products of sawmills. Based on empirical data and simulated results, the potential of birch (Betula pendula Roth, Betula pubescens Ehrh.) from commercial thinnings for combined industrial production of sawn timber and firewood billets was investigated. In the simulations, different sawing patterns were used for logs intended to combine production of sawn timber and billets for chopped firewood (‘sawlogs’), and for logs intended only to firewood production (‘firewood logs’). Finally, economical feasibility analysis was done concerning the differences between the sawmills’ traditional business concept and the novel concept combining sawn wood and firewood production. The bucking results for the volume yield of different timber assortments varied only slightly between the different bucking options, i.e. the combinations of timber assortments. The main differences in the volumes of timber assortments were due to the stand type where the birch trees were sampled (planted, naturally regenerated, mixed birch–spruce). In the sawing procedure, the output of sawn timber varied between 24% and 42% of the log volume in the sawlogs, depending on the log diameter class. As the volume yield of sawn timber and firewood billets was counted together in the case of sawlogs, the log consumption was c. 1.75 m3 of roundwood per 1 m3 of sawn timber and firewood billets. In the case of the firewood logs, the log consumption rate was considerably lower, only c. 1.35. The economic calculations showed that using the firewood approach in sawing may increase the net added value of products by €1.9–5.4 m?3 of logs, depending on their diameter class. As a conclusion, parallel production of sawn timber and firewood from logs from the first and second commercial thinning of birch-dominated stands is a concept that could work as an alliance between a sawmiller and a firewood entrepreneur. The concept could be competitive compared with both traditional sawmilling and production of chopped firewood.  相似文献   
7.
通过对数控曲线带锯机的锯切方式进行分析,最终选取带锯条的工作边绕锯齿连线摆动,同时对工件固定在工作台上做X向和Y向移动的曲线锯切形式进行讨论分析。根据这种类型曲线锯切方式的数控曲线带锯机加工曲线的工作原理,研究了数控曲线带锯机加工木材时锯条的受力状态和曲线锯路形成的过程,着重分析了带锯机曲线锯切时锯路的宽度和最小锯切半径。经过分析,总结得出数控曲线带锯机形成曲线轨迹的基本原理,基于该基本原理计算整理得到锯路宽度的估算公式及最小锯切半径的极限公式,为数控曲线带锯机加工曲线时确定其加工范围和理论出材率提供理论依据。  相似文献   
8.
针对目前市面上加工小径木的机器加工精度低、效率不高、出材率低等问题,分析提高小径木梯形板出材率、加工效率及加工精度的设计方法,通过新的设计方法制定了新的加工工艺。结合工艺分析设计了小径木梯形板锯刨机的总体结构,可以对小径木梯形板进行锯切、粗刨、精刨加工。在对其核心组件锯切组件与刨削组件的加工原理进行分析的基础上,设计了锯切组件结构与刨削组件结构。通过导入锯切主轴SolidWorks的三维模型,利用ANSYS对其锯切主轴进行静力学分析,得到锯切主轴的应力、应变和变形云图,其中最大应力值为7.435 MPa、最大应变值为0.042 316 mm/m、最大变形量为0.002 178 8 mm,其强度、刚度及变形量均在许用范围内,仿真验证了锯切主轴的设计的合理性。  相似文献   
9.
在圆锯片组锯切过程中,高速旋转的锯片与工件发生摩擦会产生大量的切削热。当圆锯片温度过高时,其振动急剧增加,变形增大,严重影响加工精度和出材率,而且存在安全隐患,为此设计了木材锯切冷却介质制冷雾化在线冷却系统。介绍了该系统的结构、工作原理、主要技术参数及系统设计。  相似文献   
10.
实现自动化原木生产是提高贮木场原木生产效率和经济效益的重要措施.东北林区处于高纬度地区,常年低温寒冷,且目前我国尚未有适用于在低温户外作业的造材机,因此需要设计相关的造材机进行作业,提高东北林区木材资源的利用.主要根据贮木场的工作环境和效益,对链式原条造材机的锯截机构进行设计.通过计算及机械手册选取标准的零件,并运用Pro/E软件对锯截机构和关键零件进行建模,完成总体装配图.在建模的过程中介绍锯截机构的工作过程和各组成部分的作用.  相似文献   
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