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Woods
Published in M. Rashad Islam, Civil Engineering Materials, 2020
Several types of wood panels are commonly available, such as plywood, oriented strand board (OSB), and composite panels. OSB is very popular for floor and wall sheathing. Plywood refers to wood structural panels comprising wood veneer arranged in cross-aligned layers. Fiberboard is made by breaking down hardwood or softwood residuals into wood fibers, and combining them with wax and a resin binder. Particle board is manufactured from wood chips, sawmill shavings, or even sawdust, and a synthetic resin or other suitable binder, which is pressed and extruded. For cross-laminated timber (CLT), each layer of boards is placed cross-wise to adjacent layers for increased rigidity and strength. Densified wood is made by using a mechanical hot press to compress wood fibers and increase the density, to enhance the strength and stiffness of the wood by a proportional amount. Currently, chemically densified wood is also available, and transparent wood composites will be available on the market, in the future.
Formaldehyde
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Particleboard is a wood by-product manufactured from fine (ca. 1 mm) wood particles that are mixed with 6–8 wt% UF resin and pressed into panels at a temperature of 150–180°C.98 It is used in residential construction for subflooring, shelving, and cabinetry. It is also used in the construction of furniture and is one of the more severe triggers of chemical sensitivity.
Reaction to fire performance
Published in Andrew Buchanan, Birgit Östman, Fire Safe Use of Wood in Buildings, 2023
Wood is the principal component in the production of a variety of engineered panel products for use in structural or decorative applications. The most common of these products are briefly described below. Additional discussion of panel products can be found in Chapter 1 of this guide and Chapter 11 of the Wood Handbook (Wood Handbook, 2010):Hardboard is manufactured primarily from inter-felted lignocellulosic fibres (usually wood), mixed with a synthetic resin and additives to improve specific properties, and consolidated under heat and pressure in a hot press. Density range ≥ 900 kg/m3.Medium-density fibreboard (MDF) is manufactured from lignocellulosic fibres in a similar fashion to hardboard but has a lower density than hardboard. Density range: 400–900 kg/m3.Oriented strandboard (OSB) is an engineered structural-use panel manufactured from thin wood strands (in North America, primarily aspen, which is a hardwood species) bonded together with water-resistant resin. The resin may have adverse effects on the reaction to fire performance. Density range: 500–800 kg/m3.Particleboard is produced by mechanically reducing the wood raw material into small particles, applying an adhesive to the particles, and consolidating a loose mat of the particles with heat and pressure into a panel product. Density range: 600–800 kg/m3.Plywood is a glued wood panel made up of an odd number (usually) of relatively thin layers of veneer (also referred to as plies) with the grain of adjacent layers at right angles. In North America, structural plywood generally is made from softwood veneers, while hardwood plywood is used primarily for decorative purposes. Density range: 350–800 kg/m3.Waferboard is a particle panel product made of wafer-type flakes. It is usually manufactured to possess equal mechanical properties in all directions parallel to the plane of the panel. Density range: 470–640 kg/m3.
Treatment of wet electrostatic precipitators wastewater by supercritical water oxidation
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Aytuğ Tekbaş, Nihal Bektaş, Mesut Tekbaş, Ercan Gürbulak, Ebubekir Yüksel
Related to a rapidly growing population and changing consumer habits, the production of wood-based panels (chipboard) used in furniture production, interior finishing, and many other fields have recently increased. Particleboard that’s produced from the oldest wood-based materials that a multi-layer structure, which consists of bonded flakes in different sizes under the influence of high pressure and heat, is widely used in particleboard production, broken wood pieces or flakes are mixed with a resin to create a sheet-like product (Ghani et al. 2018). The first stage of chipboard production is to cut wood or waste wood (round wood, sawdust, shavings, flakes, etc.) into the uniform flat chip size using special chipping machines. Then, chips go for drying and pneumatic machines can sort chips for inner and outer layers to watch the differentiate humidity level between chip’s level. In the next step, chips are mixed with liquid-binding agents to get uniform mass and then undergo hot pressing and cooling processes (Stubdrup et al. 2016). Emissions result from dryers and hot press vents that are the primary sources. The general concentrations of dust, total organic carbon (TOC), and formaldehyde emission derived from direct and indirect heating systems and dryers in particleboard plants are given in Table 1.
Investigation of the effect of process parameters on surface roughness in drilling of particleboard composite panels using adaptive neuro fuzzy inference system
Published in Materials and Manufacturing Processes, 2020
T.N. Valarmathi, K. Palanikumar, S. Sekar, B. Latha
Particleboard (PB) is finding increased applications in wall partitions, roofing, and flooring panels. The particleboard is a composite panel product manufactured by using wood waste particles. PB is a good alternative for wooden boards or plywood if the cost is a necessary criterion than strength. Drilling is extensively needed in all fields of manufacturing, furniture and automotive industries, aerospace, and structural applications. As the material removal in the drilling process is invisible during dynamic machining conditions, the selection of proper drill material, type, and geometry is a prerequisite to obtaining a smooth and functional valued drilled surface. The board density of wood-based composites has finding an essential role in the physical, chemical, and flexural properties and also the fasteners holding capabilities of the composite panels. [1–4] The tool wear is found to be higher in the machining of wood composites than the wood machining process. The tool wear in wood composites is due to abrasion and adhesion because of the presence of resin and other filler materials, also the increase of cutting forces and temperature during machining of composites.[5] The tool life is exceptionally very short in the machining of particleboards. Even the mineral contamination influences the wear on cutting edges of the tool in particleboard machining.[6] Because of high wear, oxidation, and scraped area utilization of tungsten carbide are restricted in the cutting of PB and fiberboard.[7] The influence of feed is affecting the surface quality in drilling of SiCp/Al composite with the PCD tool.[8] The rotary ultrasonic drilling of float glass is carried out and obtained good chips.[9] The delamination developed during drilling of composite laminates is found to be more when using high feed rates and larger drill diameters.[10] Thrust force and torque in drilling are more with more massive diameter drills[2,11] and less with a tremendous chisel edge and helix angle[12] and a small point angle.[13] Delamination and thrust force developed is reduced when small diameter drills are used in the drilling of wood composite panels.[14–16] The use of cellular materials for green energy in the automotive application has been analyzed.[17]