Sample records for hardboard

  1. Location Selection for Hardboard Industry in Mazandaran Province

    Directory of Open Access Journals (Sweden)

    Majid Azizi


    Full Text Available This research presents an optimum framework for hardboard industry location selection in Mazandaran Province. Considering the existence of only two depreciated hardboard plants with very old technology in Iran, the establishment of new plants are vital. To materialize this goal, Mazandaran province enjoys priorities to other provinces based on its resources of raw lignocellulosic materials required for wood and paper industries. The model presented in this article uses AHP benefit/cost ratios. The results indicate that the criterion of ‘material and production’ with a weight of 0.327 and the sub-criterion of ‘reliability of supply’ with a weight of 0.146 have the highest priorities, and the city of Sari is the best alternative.

  2. Evaluation of sequential aerated treatment of wastewater from hardboard mill

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    S. Videla


    Full Text Available Wastewater from a hardboard mill characterized by a high organic content (15-30 g/L COD was studied in a bench scale sequential aerated system in order to define a start up strategy. Inlet COD concentration varied from 0.5 to 25 g/L and the hydraulic retention time was maintained at 5 days. The sequential system proposed could reduce BOD, COD, TSS and phenol over 90% except when the inlet COD concentration was lower than 25 g/L.Água residual proveniente de uma indústria de tabuleiro de fibra dura caracterizada por ter um elevado conteúdo orgânico (15-30 g/L DQO foi estudada utilizando um sistema arejado seqüêncial de forma a definir uma estratégia de start up. A concentração de DQO na entrada do sistema variou na faixa de 0,5-25 g/L e o tempo de residência hidráulico foi mantido em 5 dias. O sistema seqüêncial proposto reduziu DBO, DQO, SST e fenol sobre 90% quando a concentração de DQO na entrada foi menor a 25 g/L.

  3. Pressing of three-layer, dry-formed MDF with binderless hardboard faces (United States)

    Otto Suchsland; George E. Woodson; Charles W. McMillin


    Severely cooked Masonite pulp was used as face material in three-layer experimental medium-density fiberboard (MDF). The core layer consisted of conventional MDF furnish with resin binder added. The faces were formed absolutely dry without additives of any kind. The three-layer mat was hot-pressed to overall densities ranging from 44 to 56 pcf. The faces had hardboard-...

  4. Evaluation of hardboard manufacturing process wastewater as a feedstream for ethanol production. (United States)

    Groves, Stephanie; Liu, Jifei; Shonnard, David; Bagley, Susan


    Waste streams from the wood processing industry can serve as feedstream for ethanol production from biomass residues. Hardboard manufacturing process wastewater (HPW) was evaluated on the basis of monomeric sugar recovery and fermentability as a novel feedstream for ethanol production. Dilute acid hydrolysis, coupled with concentration of the wastewater resulted in a hydrolysate with 66 g/l total fermentable sugars. As xylose accounted for 53 % of the total sugars, native xylose-fermenting yeasts were evaluated for their ability to produce ethanol from the hydrolysate. The strains selected were, in decreasing order by ethanol yields from xylose (Y p/s, based on consumed sugars), Scheffersomyces stipitis ATCC 58785 (CBS 6054), Pachysolen tannophilus ATCC 60393, and Kluyveromyces marxianus ATCC 46537. The yeasts were compared on the basis of substrate utilization and ethanol yield during fermentations of the hydrolysate, measured using an HPLC. S. stipitis, P. tannophilus, and K. marxianus produced 0.34, 0.31, and 0.36 g/g, respectively. The yeasts were able to utilize between 58 and 75 % of the available substrate. S. stipitis outperformed the other yeast during the fermentation of the hydrolysate; consuming the highest concentration of available substrate and producing the highest ethanol concentration in 72 h. Due to its high sugar content and low inhibitor levels after hydrolysis, it was concluded that HPW is a suitable feedstream for ethanol production by S. stipitis.

  5. Cradle-to-Gate Life-Cycle Inventory of Hardboard and Engineered Wood Siding and Trim Produced in North America (United States)

    Richard D. Bergman


    Developing wood product LCI data helps construct product LCAs that are then incorporated into developing whole building LCAs in environmental footprint software such as the Athena Impact Estimator for Buildings (ASMI 2015). Conducting whole building LCAs provide for points that go toward green building certification in rating systems such as LEED v4, Green Globes, and...

  6. 76 FR 66036 - Folding Metal Tables and Chairs From the People's Republic of China: Final Results of Antidumping... (United States)


    ... exclusively, with a hardboard top covered with vinyl or fabric. Folding metal tables have legs that... is available in the Central Records Unit (``CRU''), room 7046 of the main Department of Commerce...

  7. An evaluation of three simple phantoms used in quality assurance of automatic exposure control

    International Nuclear Information System (INIS)

    Reynolds, S.E.; Rofe, S.


    Full text: Different attenuators are used to assess the performance of x-ray systems with automatic exposure control (AEC). Three attenuators, copper, water and hardboard, were compared in this assessment. The Health Physics Service (HPS), which is part of the Department of Medical Physics and Bioengineering at Christchurch Hospital, New Zealand, has chosen to use hardboard as its patient equivalent phantom when testing x-ray equipment simply because it is generally easier to handle compared to water phantoms. Tests were conducted on the hardboard phantom in order to evaluate its effect on radiation in terms of attenuation equivalence, production of scatter and sensitivity to different kilovoltages compared to water or copper. Entrance and exit dose comparison tests were conducted using the AEC on a Philips Optimus 50 x-ray machine. A Keithley Triad Field Service Kit Model 10100A was used to record doses. The first set of tests were designed to ascertain the thickness of water and copper required to produce a similar mAs to the particular thickness of hardboard being examined. The tests were repeated with a film in a cassette which was placed in the bucky tray. Film optical densities were then measured. The hardboard phantom shows a very similar response to radiation as water and hence the human body and is therefore a suitable material for use in the construction of phantoms. Copper produces a very different radiation spectrum and its scattering effects are quite different to water or hardboard. For these reasons we consider copper to be unsuitable for use as a phantom when programming AECs. Copyright (2000) Australasian College of Physical Scientists and Engineers in Medicine

  8. Design and field tests of a modified small mammallivetrap

    African Journals Online (AJOL)

    -vinyl-chloride) and metal small mammal live-trap has been developed and subjected to field tests. The PVC traps captured greater numbers of very small rodents and shrews but fewer large rodents than did hardboard ones. s. Afr. J. Zool.

  9. Investigating food environments in selected areas of Tshwane

    CSIR Research Space (South Africa)

    Cooper, Antony K


    Full Text Available of planning and the structures are made of plastics, zinc material and hardboards. The second study was conducted in Pretoria Gardens, an old, formal, low to medium-income suburb situated in north-central Tshwane. The physical barriers impeding access...

  10. 49 CFR 178.709 - Standards for wooden IBCs. (United States)


    ... IBC. (i) Natural wood used in the construction of an IBC must be well-seasoned, commercially dry, and... be used for the construction of structural equipment of the outer packaging. (iii) Reconstituted wood used in construction of bodies must be water resistant reconstituted wood such as hardboard or particle...

  11. A profile of wood use in nonresidential building construction (United States)

    H. N. Spelter; R. G. Anderson

    This report presents estimates of the amounts of lumber, glued-laminated lumber, trusses, plywood, particleboard, hardboard, and wood shingles used in new nonresidential building construction in the United States. Use of wood products is shown for several building types, project sizes, and building components. The estimates are based on a survey of 489 projects under...

  12. 75 FR 81480 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Allegheny County's... (United States)


    ... hardboard) panel to which a protective, decorative, or functional material or layer has been applied....62 (f) metallic 0.55 4.62 0.55 4.62 (g) pretreatment coatings....... 0.55 4.62 0.55 4.62 (h) solar....06 (f) metallic 0.61 5.06 0.61 5.06 (g) pretreatment coatings....... 0.61 5.06 0.61 5.06 (h) solar...


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    Yudha Yoga Pratama


    Full Text Available Production of wood in Indonesia is no longer able to meet their need, which is opening an opportunity for study in material alternatives. Coconut fiber is very potential material for wood replacement composite, since its availability is abundant and its utilization is still low. Meanwhile, some factors have been studied as single affecting variable for natural fiber composite. The objective of this study is to evaluate the influence factors of alkali treatment, fiber length, fiber volume fraction and interaction between factors on the tensile strenght of coco-fiber polyester composite. 108 pieces of composites have been prepared as speciments of tensile test which comply ASTM D 638 standard. The testing result was processed using completely randomized full factorial experiment. The experiment showed significant difference for all three factors. The highest value of tensile strenght is 22.57 MPa for 2 hours alkali treatment, 10 mm fiber length and fiber volume fraction of 35%. This value has met the standard minimum tensile strength of hardboard according to ANSI A135.4 2004.

  14. Industrial potential for application of radiation curing in Pakistan

    International Nuclear Information System (INIS)

    Ahmed, S.


    Potential applications of radiation curing of coating are in the field of wood and wood products, drying of printing inks, ceramics (roof and floor tiles) and textiles. Pakistan a 'timber deficit' country needs to improve her wood, plywood, hardboard and particle board to make for shortage of quality wood. Imports of wood and wood products are in excess of 3000 million rupees. Radiation curing can be applied and itexcels over heat treatment. Whereas costs of high energy units (500 KeV) with scanning type are rather high, low energy (100-175 KeV) flat beam self-shielded units costing 200,000 US$ are available. For developing countries ultraviolet (UV) curing is ideally suited because of its low price, flexibility and simplicity in handling. Alternately, multipurpose bunker type facility such as 500 KeV current mA can be utilized in carrying out heat-shrinkables production, irradiation of cable and wire and curing of coatings on wood and wood products. (author)

  15. The Effect of Face and Adhesive Types on Mechanical Properties of Sandwich Panels Made from Honeycomb Paper

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    Mohsen Saffari


    Full Text Available Sandwich panels are new kind of layered composites that usually are composed of three layers and their core layer's thickness is higher and the outer layers are determinative in determination of the products strength and stiffness. The core layer is commonly made of honeycomb paper, corrugated paper and polyurethane etc. In this study, effects of face and adhesive types on mechanical properties of sandwich panels made from honeycomb paper were investigated. The variables included three types; beech face, poplar face and hardboard (S2S face, veneer less and adhesive type (two types; epoxy and PVA. Out of experimental panels specimens were cut and tested according to DIN E 326-1 standard. Mechanical properties of panels, included modulus of elasticity as well as modulus of rupture at the edge and surface (based on DIN EN 310 standard and Impact Bending Strength (IBS of the panels (based on ASTM D 3499 standard were measured. The gathered data were analyzed as completely randomized factorial design. Highest mechanical properties were reported for panels glued with epoxy resin and containing fiberboard at the middle. According to results, optimum condition of producing sandwich panels was observed in uses of epoxy resin and fiberboard S2S face, veneer less at the middle.


    Directory of Open Access Journals (Sweden)

    Yudha Yoga Pratama


    Full Text Available Production of wood in Indonesia is no longer able to meet their need, which is opening an opportunity for study in material alternatives. Coconut fiber is very potential material for wood replacement composite, since its availability is abundant and its utilization is still low. Meanwhile, some factors have been studied as single affecting variable for natural fiber composite. The objective of this study is to evaluate the influence factors of alkali treatment, fiber length, fiber volume fraction and interaction between factors on the tensile strenght of coco-fiber polyester composite. 108 pieces of composites have been prepared as speciments of tensile test which comply ASTM D 638 standard. The testing result was processed using  completely randomized full  factorial experiment. The experiment showed significant difference for all three factors. The highest value of tensile strenght is 22.57 MPa for 2 hours alkali treatment, 10 mm fiber length and fiber volume fraction of 35%. This value has met the standard minimum tensile strength of hardboard according to ANSI A135.4 2004.

  17. A study on effect of ATH on Euphorbia coagulum modified polyester banana fiber composite (United States)

    Kumari, Sanju; Rai, Bhuvneshwar; Kumar, Gulshan


    Fiber reinforced polymer composites are used for building and structural applications due to their high strength. In conventional composites both the binder and the reinforcing fibers are synthetic or either one of the material is natural. In the present study coagulum of Euphorbia royleana has been used for replacing polyester resinas binder in polyester banana composite. Euphorbia coagulum (driedlatex) is rich in resinous mass (60-80%), which are terpenes and polyisoprene (10-20%). Effect of varying percentage of coagulum content on various physico-mechanical properties of polyester-banana composites has been studied. Since banana fiber is sensitive to water due to presence of polar group, banana composite undergoes delamination and deterioration under humid condition. Alkali treated banana fiber along with coagulum content has improved overall mechanical properties and reduction in water absorption. The best physico-mechanical properties have been achieved on replacing 40% of polyester resin by coagulum. An increase of 50% in bending strength, 30% bending modulus and 45% impact strength as well as 68% decrease in water absorption was observed. Incorporation of 20% ATH as flame retardant in coagulum modified banana polyester composite enhanced limiting oxygen index from 20.6 to 26.8% and smoke density reduced up to 40%. This study presents the possibility of utilization of renewable materials for environmental friendly composite development as well as to find out alternative feedstock for petroleum products. Developed Euphorbia latex modified banana polyester composites can have potential utility in hardboard, partition panel, plywood and automotive etc.

  18. Plastic coating on paper by electron beam irradiation

    International Nuclear Information System (INIS)

    Ametani, Kazuo; Tsuchiya, Mitsuaki; Sawai, Takeshi


    It has been known long since that the resin system of unsaturated polyester and vinylmonomer mixture cures by irradiation. Ford of USA for the first time industrialized the radiation curing reaction of resins for the coating of automobile parts. Thereafter, accompanying the development and technical advance of the low energy electron beam irradiation apparatus which is suitable to surface treatment such as coating and easy to handle and the development of resins, the electron beam curing method has become to be utilized for coating hardboard and wooden doors, coating automobile tire rims, adhering printing papers and others. The electron beam curing method has advantage such as energy conservation, resource saving and little pollution because solvent is not used, high production rate and small floor space. In glossing industry, for the purpose of developing the techniques to apply electron beam curing method to glazed paper production, the selection of the composition of resins suitable to glazed papers, the irradiating condition and the properties of cured films were examined. The films withstanding bending can be obtained at low dose with urethane group, ester group or the combination of monomers. (Kako, I.)


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    Siti Suhaily,


    Full Text Available This review considers the potential and challenges of using agro-based oil palm biomasses, including the trunk, frond, empty fruit bunch, and palm press fiber biocomposites, for furniture applications. Currently, design and quality rather than price are becoming the primary concern for consumers when buying new furniture. Within this context, this paper focuses on the design of innovative, sustainable furniture from agro-based biocomposites to meet the needs of future population growth and technology. This research also discusses the need for biocomposite materials that do not depend on the growth of populations, but on the growth and development of the economy. This study focuses on globally available agro-based biocomposites, especially those from oil palm biomass: plywood, medium density fiberboard (MDF, wood plastic composite (WPC, laminated veneer lumber (LVL, oriented strand board (OSB, hardboards, and particleboard. Additional positive aspects of biocomposites are their environmentally friendly character, high quality, competitive design, and capacity to improve the value proposition of high-end products. These attributes increase the demand for agro-based biocomposite furniture on the international market.

  20. The Envirohome: Sustainable housing guidebook and reference manual

    Energy Technology Data Exchange (ETDEWEB)


    The EnviroHome was designed as part of Nova Scotia's Advanced House Project, a response to a national competition to construct the most energy-efficient and environmentally responsible homes in Canada. The house was designed to have a total purchased energy consumption 50% less than Canada's current energy efficient building standard, the R-2000 program. A guidebook is presented which describes the novel features of a three-bedroom, 2,200 ft[sup 2] Envirohome built according to the Advanced Houses Program design requirements. Features include a high-efficiency oil-fired space heating system coupled with a solar domestic hot water system; high levels of blown cellulose insulation and highly airtight construction; an 84% efficient heat recovery ventilator; passive solar design; high-performance low-emissivity windows; a recycling center in the kitchen; energy efficient appliances and lighting; integration of the performance of heating, hot water, solar collection, and ventilation systems by a direct digital control automation center; a low-pollution contraflow fireplace; and water-saving plumbing fixtures. During construction, 62% of the construction waste was recycled and 6% was reused. Over 20,000 lb of recycled material was used in building the Envirohome, including fly ash in the concrete for the foundations, newsprint in the insulation and drywall, and sawdust in the hardboard siding. Interior finishes and materials were chosen to avoid harmful emissions, and exterior finishes are virtually maintenance-free. 5 refs., 58 figs., 2 tabs.

  1. Wood waste: A disposal problem or an opportunity?

    International Nuclear Information System (INIS)

    Vajda, P.


    The utilization of wood wastes in North America is reviewed, with a focus on the wood products industry and markets. On the whole, wood mill residues in North America have always been utilized except for a period from the 1940s to the 1970s oil crisis. In the latter period, low cost electric power and hydrocarbon fuels rendered uneconomical the use of wood wastes as fuel. As a response to the problem of disposing these wastes, a number of innovations occurred in that period, including the use of wood chips for manufacturing pulp and particleboard, and the use of sawdust and shavings for manufacturing hardboard and medium density fiberboard. Uses for bark, except as fuel, have not been successfully developed. Since the 1970s, wood waste in the USA is essentially all used for composite board products and fuel. This is also true in eastern Canada, which is close to the wood products markets and which has fairly high oil and gas costs. However, in western Canada, low energy costs and small internal markets have led to a serious wood waste disposal problem. A survey of wood waste supply and demand shows large surpluses in mill residues in western Canada and some remote locations in northern Ontario and Quebec. The Pacific Rim countries are identified as a potential market for western Canadian composite board production. The use of other sources of wood waste (forestry or logging residues, which are costly to collect, and municipal construction waste) is briefly discussed

  2. The Spiritual Form of Ancient Art and Culture - Bharatanatyam (Visual Art Depicted Using Unique Techniques on Scratchboard (Fine Art Medium

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    Arpitha Parthasarathy


    Full Text Available The most ancient form of dance that is prevailing todays is a form of classical Indian dance, Bharatanatyam. In Sanskrit (and Devanagri, bharatanatyam means "Indian dance", is believed to have divine origin and is of the most ancient form of classical dance. Bharatanatyam is a two thousand-year-old dance form, originally practiced in the temples of ancient India. The art today remains purely devotional even today and this performing art is yet to gain awareness and interest in the western world. This dance form has various implications in improving the higher order thinking in children and provides health benefits in adults apart from cultural preservation. The current study uses scratchboard as a medium to display the artistic movements and emotions. Scratchboard, a fine art is one means by which the visual art is expressed in this current study using sharp tools, namely X-acto 11 scalpel and tattoo needles. This unique medium made up of a masonite hardboard coated with soft clay and Indian ink has been used to not only show the details of the ancient dance form and expression but also to comprehend and transcribe both visual art and fine art. It is for the first time that scratchboard medium has been the innovatively used to show various textures of flower, glistening gold jewels, hand woven silk and the divine expression in the same art ‘devotion’. The current study was carried out in-order to perpetuate, conserve and disseminate these classic forms of visual art and fine art.

  3. Thermoplastic polyolefins as formaldehyde free binders in highly filled lignocellulosic panel boards: using glycerine as a processing aid in kenaf fiber polypropylene boards

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    Anand Ramesh Sanadi


    Full Text Available A new technique was developed to make highly loaded (up to 95% formaldehyde free natural fiber boards. The purpose of the paper is to report a broad study on 85% kenaf boards using linear thermoplastic polymers as the binder in preparing the boards to determine if these materials have potential in commercial applications by comparing them to other commercial materials. In these materials, linear thermoplastic polymer chains act as an adhesive and the product resembles a typical wood based panel (e.g., phenol formaldehyde fiber board. The process involved the use of small amount of glycerine in the fiber to enhance processibility in a thermo-kinetic mixer followed by hot pressing. In this paper, we report the properties of 85% by weight kenaf fiber boards using polypropylene as the adhesive. A maleated polypropylene was used to improve the adhesion and stress transfer between the adhesive and kenaf fiber. The addition of 2% by weight of glycerine based on the dry weight of kenaf fiber resulted in the best properties of the boards. Differential scanning calorimetric studies suggested that the glycerine had a little effect on the percent crystallinity of the matrix. Dynamic mechanical tests of the 85% boards showed some differences compared to conventional 60% by weight kenaf-PP composites. The 85% kenaf boards had a flexural strength of 75 MPa and a flexural modulus of 6.8 GPa with a specific gravity of 1.24. These properties are comparable to standard formaldehyde free high density hardboards with flexural strengths of 48.3 MPa and flexural modulus of 5.5 GPa, and a specific gravity of 1.28. This paper gives a broad overview of an initial study of these new materials.

  4. Recovery Act: Alpena Biorefinery and Alpena Biorefinery Lignin Separation Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Retsina, Theodora [American Process Inc., Atlanta, GA (United States)


    The Alpena Biorefinery (AB) was constructed in Alpena, Michigan, at the Decorative Panels International hardboard manufacturing facility. The goal of the AB was to demonstrate a modular, technically successful, and financially viable process of making cellulosic ethanol from woody biomass extract at wood processing facilities. At full capacity, the AB can produce 894,200 gallons per year of cellulosic ethanol and 696,000 gallons per year of aqueous potassium acetate, using extract from northern hardwood and aspen woodchips feedstock. The project objectives and the value proposition of AB promote the national goals of energy independence, greenhouse gas reduction, and green job creation and retention. A successful outcome of the Alpena Biorefinery project has been commercial sales of the first ever cellulosic ethanol RINS generated from woody biomass in the US, under the EPA’s Renewable Fuels Standard Program. We believe that American Process is also likely the first company in the world to produce commercial quantities of cellulosic ethanol from mixed forest residue. Life Cycle Analysis performed by Michigan Institute of Technology found that the entire life cycle greenhouse gas emissions from the plant’s cellulosic ethanol were only 25 percent that of petroleum-based gasoline. They found the potassium acetate runway de-icer coproduct generates up to 45 percent less greenhouse gases than the production of conventional potassium acetate. The Alpena Biorefinery project created 31 permanent jobs for direct employees and helped retain 200 jobs associated with the existing Decorative Panels International facility, by increasing its economic viability through significant savings in waste water treatment costs. The AB project has been declared a Michigan Center of Energy Excellence and was awarded a $4 million State of Michigan grant. The project also received New Market Tax Credit financing for locating in an economically distressed community. All other equity funds

  5. PROTOTIPE ALAT PENGEKSTRAK PATI SAGU TIPE MIXER ROTARY BLADE BERTENAGA MOTOR BAKAR Prototype of Mixer Rotary Blade of Sago Starch Extractor Powered by Internal Combustion Engine

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    Darma Darma


    Full Text Available Papua and West Papua Province have a large potential of sago. Approximately 994,000 hectares, mostly natural sago forest was existed in this area. Sago starch has long been an important source of nutrition troughout Papua. Product of sago palm is not only starch as source of carbohydrate for food stuff, but also for basic material of industries such as paper, plywood, hardboard, and food indutries. Traditional methods are used for starch extraction in almost all part of Papu, which is not efficient and production capacity is very low. The effort to increase sago starch production could be carry out by introducing mechanical equipment (traditional to mechanized processing. The objective of this research was to design mixer rotary blade of sago starch extraction powered by internal combustion engine. The result was prototype of mechanical sago starch extractor. The prototype has high performance with extraction capacity 160 kg of disintegrated pith per hour or equal to 33 kg of wet starch per hour, extractable starch more than 99 % while starch losses in hampas less lhan 1 %. Hopefully, application of this machine to the sago farmer will transform agricultural system from subsistence to commercial. It means that increasing of economic income. In conclusion, technically and economically this prototype was feasible. ABSTRAK Provinsi Papua dan Papua Barat memiliki potensi sagu yang sangat besar. Sekitar 994.000 hektar yang sebagian besar merupakan hutan sagu alam terdapat di kedua provinsi ini. Pati sagu telah lama digunakan sebagai sumber nutrisi bagi penduduk asli papua. Pati sagu tidak hanya digunakan sebagai sumber karbohidrat, namun juga digunakan seba- gai bahan dasar industri kertas, plywood, hardbord, dan pangan. Pengolahan sagu secara tradisional yang dilakukan oleh masyarakat tidak efisien dan kapasitas produksinya sangat rendah. Peningkatan produksi dapat dilakukan dengan mengintroduksi peralatan pengolahan mekanis untuk merubah metode

  6. Umidade de equilíbrio de painéis de madeira Equilibrium moisture content of wood panels

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    Graciane Angélica da Silva


    Full Text Available Este estudo teve como objetivo a determinação da umidade de equilíbrio de painéis de madeira numa câmara de climatização e comparação dos seus valores com os obtidos através da equação de Nelson. O trabalho foi desenvolvido na Unidade Experimental de Produção de Painéis de Madeira da Universidade Federal de Lavras. Foram utilizadas amostras de aglomerado, compensado multilaminado e sarrafeado, chapa dura, OSB (Oriented Strand Board , MDF (Medium Density Fiberboard, HDF (High Density Fiberboard, madeira-cimento e madeira-pl��stico, sendo esses produtos de escala industrial e experimental. As dimensões dos corpos-de-prova foram de 2,60 cm de largura por 2,60 cm de comprimento. As espessuras foram aquelas mais utilizadas comercialmente de cada produto, sendo utilizadas cinco repetições por painel. Os corpos-de-prova foram pesados e levados para uma câmara de climatização, onde foram submetidos a diferentes condições de umidade relativa (90, 80, 70, 60, 50 e 40% e uma temperatura constante de 30 ºC. Determinaram-se a histerese e a umidade de equilíbrio, que variaram de 40 a 90%. Os resultados indicaram que a equação de Nelson se mostrou eficiente na estimativa da umidade de equilíbrio e que não existe em média diferença de histerese entre os produtos estudados, mostrando que todos apresentam a mesma estabilidade dimensional. Observou-se, também, que o revestimento dos painéis não afetou a umidade de equilíbrio.This study aimed at determining the equilibrium moisture content of wood panels in a climatization chamber and comparing the values of equilibrium moisture content found with those given by Nelson's equation. The research was developed at the Experimental Unit of Wood Panel Production of the Universidade Federal de Lavras. Samples of particleboard, plywood, hardboard, OSB (Oriented Strand Board, MDF (Medium Density Fiberboard, HDF (High Density Fiberboard, cement wood and plastic wood were taken both from

  7. Modelos lineares e não lineares inteiros para problemas da mochila bidimensional restrita a 2 estágios Linear and nonlinear integer models for constrained two-stage two-dimensional knapsack problems

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    Horacio Hideki Yanasse


    Full Text Available Neste trabalho revemos alguns modelos lineares e não lineares inteiros para gerar padrões de corte bidimensionais guilhotinados de 2 estágios, incluindo os casos exato e não exato e restrito e irrestrito. Esses problemas são casos particulares do problema da mochila bidimensional. Apresentamos também novos modelos para gerar esses padrões de corte, baseados em adaptações ou extensões de modelos para gerar padrões de corte bidimensionais restritos 1-grupo. Padrões 2 estágios aparecem em diferentes processos de corte, como, por exemplo, em indústrias de móveis e de chapas de madeira. Os modelos são úteis para a pesquisa e o desenvolvimento de métodos de solução mais eficientes, explorando estruturas particulares, a decomposição do modelo, relaxações do modelo etc. Eles também são úteis para a avaliação do desempenho de heurísticas, já que permitem (pelo menos para problemas de tamanho moderado uma estimativa do gap de otimalidade de soluções obtidas por heurísticas. Para ilustrar a aplicação dos modelos, analisamos os resultados de alguns experimentos computacionais com exemplos da literatura e outros gerados aleatoriamente. Os resultados foram produzidos usando um software comercial conhecido e mostram que o esforço computacional necessário para resolver os modelos pode ser bastante diferente.In this work we review some linear and nonlinear integer models to generate two stage two-dimensional guillotine cutting patterns, including the constrained, non constrained, exact and non exact cases. These problems are particular cases of the two dimensional knapsack problems. We also present new models to generate these cutting patterns, based on adaptations and extensions of models that generate one-group constrained two dimensional cutting patterns. Two stage patterns arise in different cutting processes like, for instance, in the furniture industry and wooden hardboards. The models are useful for the research and