Log sawing positioning optimization and log bucking of tropical hardwood species to increase the volume yield

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.     

海南橡胶树木材加工利用现状

橡胶木是天然橡胶生产的重要副产品,也是海南产量最大的商品材。通过对海南生产单位橡胶木加工利用现状的调查,分析了海南橡胶木锯材制材、防腐和干燥过程的工艺状况,探讨存在的问题,并提出促进海南橡胶木加工利用的建议。     

Costs of protable sawmilling timbers from the acacia woodlands of western Queensland,Australia

Portable sawmilling trials with Acacia aneura (mulga) and A. cambagei (gidgee) have been undertaken to estimate the private landholder costs associated with small-scale timber production from woodlands in western Queensland, Australia. A time study of harvesting and milling operations facilitated estimation of landholder labour input requirements. The scarcity and small size of millable logs, coupled with the prevalence of timber defects, make harvesting and portable sawmilling of western Queensland acacias an expensive undertaking for landholders. The cost of producing sawn timber that meets the High Feature (HF) grade of Australian Standard AS2796 is estimated at between A$3,000/m³ and A$3,400/m³ of HF timber.     

一种小径木制材工艺及其关键设备

以一种较为先进的小径材制材生产工艺流水线为例，分析各工艺流程与关健设备，为我国制材技术与装备的发展提供参考。     

Community Forestry Enterprises in Mexico: Sustainability and Competitiveness

Community-based forest management, such as Community Forest Enterprises (CFEs), has the potential to generate positive socioenvironmental and economic outcomes. We performed a detailed survey of financial and production parameters for 30 of the approximately 992 CFEs in Mexico in order to estimate costs, income, profits, and sustainability of harvest levels for forest management, harvest, and sawmilling. Fourteen of the 30 CFEs harvested more timber than they grew in 2011, suggesting issues with sustainability, but only two of these had harvest far above annual growth, and five of those were only a fraction more than annual growth. All of the 30 CFEs except one made profits in forest management and timber growing. For timber harvesting, 22 of 30 CFEs made profits, but the losses were small for the other CFEs. For the 23 CFEs with sawmills, 18 made profits and five had losses; the greatest returns for the CFEs accrued to those with sawmills for lumber production. On average, the CFEs surveyed had high costs of production relative to other countries, but the CFEs were still profitable in national lumber markets. If Mexico were to begin importing large amounts of lumber from lower cost countries, this could pose a threat to CFE profitability.     

双向抛木机与对称制材工艺的应用

介绍我国制材生产线常见的工艺流程，结合当前国情，设计出对称制材工艺方案，以及能实现对称制材工艺的新型原木双向抛木机。     

中国与欧洲国家制材工业的对比分析

总结中国制材工业的现状,并与欧洲等国家先进加工技术进行比较.通过优势、劣势、机遇和挑战的模式分析,对中国制材工业提出中肯的评价,并就未来发展提出建议.     

Management of product development projects in the wood industry

Abstract

This study used data on project management from 70 recent product development projects in the wood industry. The objective was to test the influence of some project management factors, known from cross-industry research to be keys to product development project success, on product development project success in the context of the wood industry. Through the use of hierarchical multiple regression analysis, it was found that both the sharpness of the product concept definition and the strength of the project leader had significant positive influences on the success of product development projects. Conversely, product advantage, team cross-functionality and customer involvement did not have a significant positive influence on the success of these projects. The latter even indicated a negative influence on product development project success. Project uncertainty, as manifested in the degree of newness of the technology and the marketing strategies of the product to the innovating strategic business unit, did not influence the relationship between project management factors and product development project success. Some of the findings were unexpected and may be explained by the industry's unaccustomedness to customer co-operation and the fact that product development in the wood industry takes place within conventional technology and market bounds.     

我国家庭投资理财规划的现状和对策

橡胶木是天然橡胶生产的重要副产品,也是海南产量最大的商品材。通过对海南生产单位橡胶木加工利用现状的调查,分析了海南橡胶木锯材制材、防腐和干燥过程的工艺状况,探讨存在的问题,并提出促进海南橡胶木加工利用的建议。