共查询到19条相似文献，搜索用时 437 毫秒
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内蒙古大兴安岭林区贮木场归装机械主要是采用架杆绞盘机和归装桥.架杆绞盘机是我国当前使用最为广泛的归装机械,在东北林区约占74%左右。这种机械的结构简单,制造维修方便,造价低廉。在我国贮木场使用归装桥作业已有十五年历史了,归装桥的结构与悬臂龙门起重机相仿。归装桥是提式机械,机动性较好,很适用于贮木场原木装卸作业,特别是原木归楞作业.为了充分提高生产效率,下面探讨一下归装机械的 相似文献
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周忠臣 《林业机械与木工设备》1984,(5)
建国三十五年来,东北林区贮木场的经营管理、生产工艺和机械设备有了很大发展.特别是贮木场机械设备发展更迅速.下面,结合贮木场设计与调研工作的实践,谈谈这方面的情况. 一、贮木场设备发展的几个阶段贮木场设备的发展是和贮木场的生产特点密切联系的. 五十年代原木到材阶段,贮木场只是 相似文献
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吉林林区是我国东北的主要木材生产基地之一。该林区现有17个林业局,19个贮木场,共有机械化原木生产线30条。这些生产线平均每年完成原条造材量约385—400万 m~3,相当于完成原木产品350—370万 m~3。可见生产线的建立与运用,对林业局完成国家的木材生产任务,提高贮木作业的机械化水平起到了十分重要的作用。同时也必须看到,在原木生产线的建设与改建过程中,由于对生产线总体生产能力的形成,各工序 相似文献
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本文对东北，内蒙古林区贮木场造材工作存在的问题进行了探讨与研究，并结合贮木场的生产实际，提出相应的改进措施。 相似文献
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多年来，东北、内蒙主林区利用“冬季黄金季节”进行伐区作业和运输生产，取得良好的经济效益，那种随到随卸随造的生产方式已形成规律。这种突击性的生产方式造成贮木场生产的不均衡，给贮木场生产与管理带来很多问题，直接制约着贮木场的发展。在木材运输到贮木场作业之间设置原条贮备区，用它来缓和到材不均衡和调节贮木场生产的不均衡性，是实现贮木场均衡生产的根本措施。根据东北、内蒙古林区贮木场的现状，结合贮木场生产与发展，对东北、内蒙古林区贮木场原条贮备工艺布局进行了分析研究，并将原条贮备工艺布局分为横向贮备工艺布局、纵向贮备工艺布局和纵横结合贮备工艺布局三种类型，通过详细分析比较，指出了各种原条贮备工艺布局的优、缺点和适用条件。 相似文献
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当前我国贮木场的造材作业,绝大多数都是采用手提式电动链锯来完成。虽然手提式电动链锯与原始的人力锯相比,其造材效率高,使用方便,也减轻了一定的劳动强度。但继续以手提式链锯为主进行造材是不适合进一步减轻操作者的劳动强度和改善劳动条件的;也不利于实现造材作业的全盘机械化和自动化。为了改善这种局面,不少林区的贮木场和科研部门对各种固定锯机(如柴河、亚布力的门式双片锯机,壮志的平衡 相似文献
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贮木场生产和经营管理的好坏,是影响林业企业经济效益的重要环节。因此,有必要对原条造材及原木售价的承包与计算问题提出如下意见,供林业企业工作参考。我们认为,林业局或林场确定贮木场第二年的造材出材率(指平均出材率)和原木平均售价,从而确定其总产值并承包给贮木场,可根据贮木场前一年的原条造材出材率、原木平均售价和第二年的伐区资源状况来确定。林业 相似文献
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造材是将伐倒木锯截成原木、短圆材或任意长度木材的过程,造材在木材采运作业中为木材拖曳集材、全载集材或索道集材作准备。大多数的造材作业使用链锯进行,伐木与造材一般使用一台汕锯。已被逐渐普遍采用的原条和长原木拖集,导致了造材更多地在装车场进行,相应地林中造材就减少了。 相似文献
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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 相似文献
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Pedro Ah Shenga Peter Bomark Olof Broman Dick Sandberg 《Wood material science & engineering》2017,12(4):257-262
The sawmill industry is a very important link in the Mozambique forest products value chain, but the industry is characterized by undeveloped processing technology and high-volume export of almost unrefined logs. The low volume yield of sawn timber has been identified as a critical gap in the technological development of the industry. To improve the profitability of the industry, there is thus a need to develop methods and techniques that improve the yield. In this paper, different positioning of logs prior to sawing and the possibility of increasing the volume yield of crooked logs by bucking the logs before sawing have been studied. A computer simulation was used to study the cant-sawing and through-and-through sawing of the logs to determine the volume yield of sawn timber from the jambirre (Millettia stuhlmannii Taub.) and umbila (Pterocarpus angolensis DC.) species. The optimal position, i.e. the position of the log before sawing that gives the highest volume yield of sawn timber for a given sawing pattern when the positioning parameters, offset, skew and rotation, are considered gave a considerable higher volume yield than the horns-down position. By bucking very crooked logs and using the horns-down positioning before sawing, the volume yield can be of the same magnitude as that obtained by optimal positioning on full-length (un-bucked) logs. The bucking reduces the crook of the logs and hence increases the volume yield of sawn timber. 相似文献
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为更好地利用农作物秸秆资源,本研究设计一款采用锯切方式粉碎秸秆的机器。文章主要介绍了秸秆锯切式粉碎机的设计思想、设计方案、基本结构以及工作原理,并对切削系统进行相应的力学计算。 相似文献
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为了便于林间小径原木的运输,研制了林间自走式小型锯段机。对该机的工作原理及各部分结构进行了分析说明,并对主轴部分做了有限元分析。该机具有性能可靠、操作简单、生产率高等特点。 相似文献
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《Wood material science & engineering》2013,8(1-2):1-11
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
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建立了一个复合机构构成的椭圆形状专用加工机构,并建立复合机构各点的数学模型和运动轨迹的理论推导.利用VB6.0作为开发工具,编制了仿真软件,并对该椭圆机构进行了运动仿真和仿真结果分析,直观地看到它的运动轨迹和参数变化曲线.通过仿真选择正确的设计参数和获得某些必要的工作性能参数,极大地提高了椭圆锯切机的设计进度. 相似文献
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for wood manufacturers around the world, the single biggest cost factor is known to be its raw material. Maximum volume recovery of this raw material is, therefore, of key importance for the industry. The wood products industry consists of several interrelated manufacturing steps for converting trees into logs and logs into finished lumber. Each operation usually optimises its functionality in isolation from the preceding and following operations. It is a well documented fact that the optimisation of decisions through the whole chain of operations is considerably more profitable than the optimisation of individual operations. The objective of this study was to determine the optimal machine settings for two interrelated operations, namely the sawing and ripping operations which have tradition? ally been optimised individually. A model, having two decision variables, was developed which aims to satisfy market demand at a minimal cost. The first decision was how to saw the log supply into different thicknesses by choosing specific sawing patterns. The second was to decide on a rip saw's priority value settings, which determines how the products from the primary sawing operation are ripped into products of a certain thickness and width. The techniques used to determine the machine settings included static simulation with the SIMSAW software to represent the sawing operation and mixed integer programming to model the ripping operation. A metaheuristic, namely the Population Based Incremental Learning algorithm, was used to link the simulation and mixed integer models and to determine the optimal settings for the combined process. The model's objective function was to minimise the cost of production. This cost included the raw material waste cost and the over or under production cost. The over production cost included the stock keeping costs and the under production cost was estimated as the buy?in cost of under supplied products from another wood supplier. The model performed well against current decision software available, namely the Sawmill Production Planning System package, which combines simulation and mixed integer programming techniques to maximise profit. The model added further value by modelling and determining the ripping priority settings in addition to the primary sawing patterns. 相似文献
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20世纪以来,我国从俄罗斯进口大量的木材,以弥补国内木材原材料供应的严重不足。这些木材大多从我国东北地区边境口岸城市进入,经过锯材加工和人工干燥后再运往内地进行深加工。因此,这些口岸城市先后安装和建造了一定数量的木材干燥设备,使木材干燥生产具有了一定的规模。本文对我国东北地区主要边境口岸城市的木材干燥生产情况进行简述,并对生产中出现的一些问题进行探讨。其讨论的问题可供当地及其他地区的木材干燥生产参考,对提高木材干燥生产质量具有一定的实际意义。 相似文献
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孟庆午 《林业机械与木工设备》2008,36(9)
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. 相似文献