Fatigue strength and design stress of oil palm wood for?furniture?application

Oil palm wood (OPW) and oil palm empty fruit bunches based particleboard (OPEFBP) furniture components were tested on edge in order to determine their resistance to fatigue. Tests were carried out at selected stress levels that corresponded to specific percentages of the material’s ultimate strength (modulus of rupture—MOR). Generally, the materials fatigue life decreased as the levels of stress increased, and the allowable design stresses for the OPW and OPEFBP furniture components could be set at 40% of their respective MOR. The study also showed that OPW does not perform as well as solid Rubberwood in cyclic loading, but the OPEFBP showed similar fatigue performance to the conventional Rubberwood-based particleboard.     

Effect of pre-mechanical compression on free water removal,drying collapses and associated internal voids of oil palm wood

European Journal of Wood and Wood Products - To prevent defects caused by drying collapse, transverse pre-mechanical compression with lateral restraint of green oil palm wood (OPW) before...     

Bending and fatigue strength of mortise and tenon furniture joints made from oil palm lumber

The bending and fatigue strengths of rectangular mortise and tenon furniture joints made from oil palm lumber and solid Rubberwood were compared. The results showed that the ultimate bending moment of the oil palm lumber joints were half of the strength value of Rubberwood joints. The results showed that for both materials the allowable design stresses for rectangular mortise and tenon joints could be set at 20% of its bending strength.     

Evaluation on some finishing properties of oil palm plywood

Oil palm is the largest and most important plantation crop in Malaysia. The oil palm generally lasts for 25–30 years before the next replantation is done. Substantial amount of biomass in the form of palm trunk results from plantation cycle. This resource is simply left on the ground to decay and is not used as raw material to manufacture any kind of value-added products. The objective of this study was to investigate the possibility of manufacturing plywood from oil palm trunks and to evaluate some of the finishing properties of such experimental panels in comparison to those from Shorea sp as control samples. Three-ply plywood samples were produced from 5 mm thick veneers of oil palm using urea formaldehyde adhesive. Three types of chemicals, namely nitrocellulose, pre-catalyzed lacquer and polyurethane were used to finish experimental panels. The surface finished with nitrocellulose had the lowest contact angle on raw surface of oil palm plywood and wood. The average cross cut tape index of oil palm plywood was comparable to Shorea sp. All finishing materials of oil palm plywood produced impact rating of 4 except for surface finished with nitrocellulose while finishing on wood indicated an impact rating of 3. Oil palm plywood had higher weight loss compared to Shorea sp. Based on results from contact angle, cross cut tape index, impact rate test, weathering, and soil burial test methods it appears that the samples showed acceptable finishing properties comparable to those of solid wood.     

Dimensional stability of heat oil-cured particleboard made with oil palm trunk and rubberwood

Dimensional stability of heat oil-cured particleboard made with admixture of oil palm trunk and rubberwood was evaluated. Particleboard made with oil palm trunk had better dimensional stability due to better compact ratio and lower hygroscopicity than rubberwood. Combination of repellent properties of oil and application of heat had greatly reduced the hygroscopicity of particleboard by decreasing its equilibrium moisture content, thickness swelling and water absorption.     

Density and humidity gradients in veneers of oil palm stems

Large variations in the stem of oil palm in terms of moisture content and density hinder its full utilization in the plywood industry. In this study, the density and moisture content (MC) pattern throughout the trunk of the oil palm tree were measured and established. The veneer samples were taken from various sections i.e., top, bottom, outer and inner parts of the trunk and the density and moisture content of each veneer were then measured. The results showed that there was a decrease of density and an increase of moisture content in the veneers as they were peeled progressively towards the inner portion of the trunk. It was also discovered that veneers taken from the top part of the stem had higher density but did not have a significant difference in MC compared to veneers taken from the bottom part of the stem.     

Density and humidity gradients in veneers of oil palm stems

Large variations in the stem of oil palm in terms of moisture content and density hinder its full utilization in the plywood industry. In this study, the density and moisture content (MC) pattern throughout the trunk of the oil palm tree were measured and established. The veneer samples were taken from various sections i.e., top, bottom, outer and inner parts of the trunk and the density and moisture content of each veneer were then measured. The results showed that there was a decrease of density and an increase of moisture content in the veneers as they were peeled progressively towards the inner portion of the trunk. It was also discovered that veneers taken from the top part of the stem had higher density but did not have a significant difference in MC compared to veneers taken from the bottom part of the stem.     

Particleboards production from date palm biomass

Date palm biomass is a renewable natural resource that has not widely been utilized in industry. The objective of this study was to examine some chemical properties of date palm trunk and rachis (holocellulose, cellulose, lignin and extractives) and to evaluate their suitability to produce composite panels. Particleboards were produced using trunk and rachis as an alternative raw material for forest products industry in the presence of two types of polycondensation resins (phenol–formaldehyde and melamine urea–formaldehyde) which were selected as binding agents. The panels were tested for their physical (water absorption and thickness swelling) and mechanical (modulus of rupture, modulus of elasticity and internal bond strength) properties. The internal bond strength of date palm trunk and date palm rachis based boards met the requirements of the general purpose product standards (EN 312) at 0.70 g/cm³ density. The panels made with phenol–formaldehyde resin showed better performance with respect to the panels made with melamine urea–formaldehyde. In addition, the particleboard made with date palm trunk particles had better quality compared to the particleboard made from date palm rachis particles. Based on preliminary results of this work, raw materials from date palm trunks and rachis can have a promising potential in the manufacture of particleboards and as a substitute for wood in board production.     

Mechanical properties of wood treated with PF-pyrolytic oil resins

Jack pine and sugar maple wood samples were treated in a two-step process that involved first a copper chloride or a copper chloride-sodium borate mixture and then a phenol-formaldehyde resin containing a certain percentage of softwood bark pyrolytic oil. Various controls were also prepared for comparison. The modulus of rupture (MOR) of jack pine samples was generally negatively affected by the treatment, the observed values being lower than those of the controls. These values were statistically lower or equal to those of untreated samples. On the other hand, the modulus of elasticity (MOE) of treated jack pine samples was not found to be statistically different from that of the untreated wood. Mechanical properties behaved in a similar way for sugar maple wood. Unlike the other treatments, copper chloride–sodium borate and the resin containing 85% of pyrolytic oil as phenol substitute appeared to slightly improve the mechanical properties of both wood species even if not significantly so. Treatment with PF-pyrolytic oil resin resulted in similar or slightly better mechanical properties when compared to CCA-treated wood. The amount of treating water soluble salts retained in samples after the first treatment had a significant impact on MOR of both wood species and on MOE of sugar maple.     

Effect of oil type, temperature and time on moisture properties of hot oil-treated wood

This paper focuses on the moisture properties of wood treated in palm oil-, soy oil- and slack wax for different processing times and temperatures. Also, the relative importance of oil uptake and thermal modification on the wood moisture properties is investigated. Slack wax was better than palm oil or soy oil in improving the moisture performance of thermally treated wood, and treatment at 220 °C was superior to treatment at 200 °C, with 4 h being generally better than 2 h treatment. Water absorption in samples treated with wax at 100 °C or 160 °C was similar to that in samples treated at high temperatures while improved anti-shrink efficiencies (ASE) and lower hygroscopicities occurred only for the high temperature treatments. Chloroform extracted samples treated at high temperature with palm oil or soy oil had relatively similar hygroscopicity and ASE properties compared to unextracted samples, but had greatly increased water absorption properties. These results confirm that chemical reactions in wood resulting from the heat treatment account for the main improvements of wood properties in reduced hygroscopicity and improved dimensional stability, while the oil absorbed by wood reduces the rate of water absorption.     

基于ANSYS/LS-DYNA的实木家具跌落仿真分析

本研究基于ANSYS/LS-DYNA的结构动力分析模块,建立经简化的实木家具的有限元模型,利用计算机有限元方法实现跌落仿真模拟,分析其结构对跌落的响应,获得应力云图、速度和加速度响应等各种参数,并结合材料性能参数进行了对照分析,节约了实测成本与费用.本研究利用有限元法验证了实木椅子结构设计的合理性,并探索了计算机跌落仿...     

木材美学在家具设计上的应用

本文探讨了木材的美学属性及其对家具设计的意义,并以泡桐木材为例探索了木材微观构造美学元素应用于家具造型与装饰设计的可行性。借助现代显微技术,发掘木材内部构造的天然之美,并把木材的天然构造之美应用于家具设计,这是一种人文与自然相结合、艺术与技术相结合的设计方法,是一种崇尚自然的设计理念,期待能够为家具设计探索出一条新的思路。     

Evaluation of innovative technological approaches to replace palm fat with physically modified Swiss rapeseed oil in bakery products

Palm fat is often used in baked goods because of its relatively low cost, and its positive impact on texture and shelf life. Demand for alternatives has risen in recent years due to concerns about the ecological and social sustainability. This is a challenge for the bakery industry since palm fat possesses unique properties. In this study, unhydrogenated rapeseed oil was processed using novel physical technologies, such as wax crystallisation, stabilised foaming and Pickering emulsions, in order to simulate palm fat properties. Analysis showed that while the initial viscosity of the fat substitute products was low compared to palm fat, the fat replacement products behaved very similarly to palm fat in the baking experiments. The resulting biscuits baked with emulsified rapeseed oil and rapeseed oil complemented with wax crystals were judged to be suitable replacements for palm fat in terms of processability, as well as analytical and sensory assessment.     

马来西亚棕榈油在食品和饲料中的应用及油棕行业可持续发展的研究进展

目前棕榈油是全球第一大产量的植物油,其性状稳定,含有丰富的维生素 E和类胡萝卜素等营养成分,且价格具有竞争力,因此被广泛应用于食品加工及饲料等行业。马来西亚作为世界棕榈油主要生产国和出口国之一,对全球棕榈油市场具有重要贡献。综述了马来西亚棕榈油生产、贸易及可持续发展状况,并对棕榈油在食品和饲料行业的应用进行总结,以期为棕榈油的消费和应用提供参考。     

Ethanol and lactic acid production using sap squeezed from old oil palm trunks felled for replanting

Old oil palm trunks that had been felled for replanting were found to contain large quantities of high glucose content sap. Notably, the sap in the inner part of the trunk accounted for more than 80% of the whole trunk weight. The glucose concentration of the sap from the inner part was 85.2 g/L and decreased towards the outer part. Other sugars found in relatively low concentrations were sucrose, fructose, galactose, xylose, and rhamnose. In addition, oil palm sap was found to be rich in various kinds of amino acids, organic acids, minerals and vitamins. Based on these findings, we fermented the sap to produce ethanol using the sake brewing yeast strain, Saccharomyces cerevisiae Kyokai no.7. Ethanol was produced from the sap without the addition of nutrients, at a comparable rate and yield to the reference fermentation on YPD medium with glucose as a carbon source. Likewise, we produced lactic acid, a promising material for bio-plastics, poly-lactate, from the sap using the homolactic acid bacterium Lactobacillus lactis ATCC19435. We confirmed that sugars contained in the sap were readily converted to lactic acid with almost the same efficiency as the reference fermentation on MSR medium with glucose as a substrate. These results indicate that oil palm trunks felled for replanting are a significant resource for the production of fuel ethanol and lactic acid in palm oil-producing countries such as Malaysia and Indonesia.     

Effect of adhesive type and glue-line thickness on the fatigue strength of mortise and tenon furniture joints

The fatigue strength of rectangular mortise and tenon rubberwood furniture joints made from polyvinyl-acetate (PVAc) and urea-formaldehyde (UF) adhesives were compared. The results showed that the allowable design stress for PVAc adhesive joints could be set at 30 % of its ultimate bending moment as compared to 25 % for the UF adhesive joint. Further, PVAc adhesive joints have large working tolerances for glue-line thicknesses which make it suitable for mass production furniture manufacturing.     

石材家具设计初探

石材作为一种传统的天然材料很早就运用于家具设计中,由于受材料特性及加工技术的影响,在家具设计的运用上受到较大的局限,随着当代加工技术的不断更新,使石材在家设计中的运用得到扩展。本文从新的石材加工工艺角度结合中国文化传统来探讨石材家具的设计方法。     

宋代家具材料探析

宋代是中国高型家具发展的关键阶段,缺少该时期的积累,明式家具的繁荣便无从谈起,因此,宋代家具是中国家具研究的重要课题。鉴于长期以来家具界、艺术界对宋代家具材料的研究甚少,本文力图探析出它的运用状况与特征。宋代家具材料有木、竹、藤、草、石、玉、陶、瓷等,并以木材为主,其种类繁多,多就地取材,其中有杨木、桐木、杉木等软木,榆木、枣木、楸木、梓木、杏木、柏木、楠木等柴木,乌木、檀香木、花梨木等硬木。     

Finishing characteristics of heat treated and compressed Rubberwood

The finishing characteristics of heat-treated and compressed Rubberwood were studied. It was found that heat-treated samples had significantly lower finish adhesion strength compared to the conventionally kiln-dried Rubberwood samples, which were used as control specimens. Further, compression of the specimens had also reduced its surface roughness, with an adverse effect on the finish adhesion strength. Inevitably, the use of heat treated and compressed wood in furniture may be suitable for applications, where lower finish adhesion strength could be tolerated at the expense of better finish film quality and process economics, especially in the manufacture of outdoor wooden furniture.     

橡胶木在经济适用型家具中的应用

介绍了橡胶木的基本特性和橡胶木的应用情况,评价和分析了橡胶木作为经济适用型家具用材的。