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Defibrator
The defibrator is a machine used as part of the manufacturing process for MDF man-made wooden board. It produces fine wooden fibres, finer than the cut chips used to make chipboard. Although small, these fibres retain good structural integrity. The machine itself is a thermo mechanical pulping refiner in which the pulp material, such as wood chips, is ground in an environment of steam between a rotating grinding disc (rotor) and a stationary disc (stator) each with radial grooves that provides the grinding surface. Wood chips are fed into the centre and are broken down as the centrifugal force pushes them towards the circumference of the discs where the grooves are finer to produce wood fibre. The size of the refined fibres can to some extent be controlled by altering the distance between the discs where a closer distance produces finer fibres but also requires higher grinding force. The capacity per machine is largely determined by the size of the machine, as well as the motor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arne Asplund
Dr. Arne Asplund (1903 – 1993) was a Swedish inventor. He invented the Defibrator pulping refiner and the defibrator-method (also called Asplund-method) for pulping wooden chips in 1930s. His invention resulted in the company AB Defibrator in Stockholm which was merged with Sunds AB to form Sunds Defibrator in 1979. Asplund was rewarded the ''Gold medal'' (Guldmedaljen) of the Royal Swedish Academy of Engineering Sciences The Royal Swedish Academy of Engineering Sciences (, IVA), founded on 24 October 1919 by King Gustaf V, is one of the royal academies in Sweden. The academy is an independent organisation, which promotes contact and exchange between business, ... (IVA) in 1947 for the invention and his further development of the defibrator-method for pulping wood and other fibre rich materials. He was later rewarded the ''Great gold medal'' (Stora guldmedaljen) from IVA in 1969 for his efforts on defibration technology. In 2014 Asplund was inducted to the Paper Indu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medium-density Fibreboard
Medium-density fibreboard (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibre, often in a defibrator, combining it with wax and a resin binder, and forming it into panels by applying high temperature and pressure. MDF is generally denser than plywood. It is made up of separated fibre but can be used as a building material similar in application to plywood. It is stronger and denser than particle board. The name derives from the distinction in densities of fibreboard. Large-scale production of MDF began in the 1980s, in both North America and Europe. Over time, the term "MDF" has become a generic name for any dry-process fibreboard. Physical properties MDF is typically made up of 82% wood fibre, 9% urea-formaldehyde resin glue, 8% water, and 1% paraffin wax. The density is typically between . The range of density and classification as light-, standard-, or high-density board is a misnomer and confusing. The density of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Particle Board
Particle board, also known as particleboard or chipboard, is an engineered wood product, belonging to the wood-based panels, manufactured from wood chips and a synthetic, mostly formaldehyde-based resin or other suitable binder, which is pressed under a hot press, batch- or continuous- type, and produced. Particle board is often confused with oriented strand board (OSB, also known as flakeboard, or waferboard), a different type of fiberboard that uses machined wood flakes and offers more strength. Characteristics Particle board is cheaper, denser, and more uniform than conventional wood and plywood and is substituted for them when cost is more important than strength and appearance. Particleboard can be made more appealing by painting or the use of wood veneers on visible surfaces. Though it is denser than conventional wood, it is the lightest and weakest type of fiberboard, except for insulation board. Medium-density fibreboard and hardboard, also called high-density fibe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermo Mechanical Pulp
Pulp is a fibrous lignocellulosic material prepared by chemically, semi-chemically, or mechanically isolating the cellulosic fibers of wood, fiber crops, waste paper, or rags. Mixed with water and other chemicals or plant-based additives, pulp is the major raw material used in papermaking and the industrial production of other paper products. History Before the widely acknowledged invention of papermaking by Cai Lun in China around AD 105, paper-like writing materials such as papyrus and amate were produced by ancient civilizations using plant materials which were largely unprocessed. Strips of bark or bast material were woven together, beaten into rough sheets, dried, and polished by hand. Pulp used in modern and traditional papermaking is distinguished by the process which produces a finer, more regular slurry of cellulose fibers which are pulled out of solution by a screen and dried to form sheets or rolls. The earliest paper produced in China consisted of bast fiber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood Chips
Woodchips are small- to medium-sized pieces of wood formed by cutting or chipping larger pieces of wood such as trees, branches, logging residues, stumps, roots, and wood waste. Woodchips may be used as a biomass solid fuel and are raw material for producing wood pulp. They may also be used as an organic mulch in gardening, landscaping, and ecosystem restoration; in bioreactors for denitrification; and as a substrate for mushroom cultivation. The process of making woodchips is called wood chipping and is done using a wood chipper. The types of woodchips formed following chipping is dependent on the type of wood chipper used and the material from which they are made. Woodchip varieties include: forest chips (from forested areas), wood residue chips (from untreated wood residues, recycled wood and off-cuts), sawing residue chips (from sawmill residues), and short rotation forestry chips (from energy crops). Raw materials The raw materials of woodchips can be pulpwood, waste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steam
Steam is water vapor, often mixed with air or an aerosol of liquid water droplets. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Saturated or superheated steam is invisible; however, wet steam, a visible mist or aerosol of water droplets, is often referred to as "steam". When liquid water becomes steam, it increases in volume by 1,700 times at standard temperature and pressure; this change in volume can be converted into work (physics), mechanical work by steam engines such as reciprocating engine, reciprocating piston type engines and steam turbines, which are a sub-group of steam engines. Piston type steam engines played a central role in the Industrial Revolution and modern steam turbines are used to generate more than 80% of the world's electricity. If liquid water comes in contact with a very hot surface or depressurizes quickly below its vapor pressure, vapour pressure, it can create a steam exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood Fibre
Wood fibres (also spelled wood fibers, see spelling differences) are usually cellulosic elements that are extracted from trees and used to make materials including paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses, Feces#Other uses, herbivore dung, or other vegetable sources in water. Once the water is dra .... The end paper product (paper, paperboard, tissue, cardboard, etc.) dictates the species, or species blend, that is best suited to provide the desirable sheet characteristics, and also dictates the required fibre processing (chemical treatment, heat treatment, mechanical "brushing" or refining, etc.). In North America, virgin (non-recycled) wood fibre is primarily extracted from hardwood (deciduous) trees and softwood (coniferous) trees. The wood fibre can be extracted as a primary product, or collected during the milling of lumber. Wood fibres can also be re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refine
Refining is the process of List of purification methods in chemistry, purification of a (1) chemical compound, substance or a (2) Theory of Forms, form. The term is usually used of a natural resource that is almost in a usable form, but which is more useful in its pure form. For instance, most types of natural petroleum will burn straight from the ground, but it will burn poorly and quickly clog an engine with residues and by-products. The term is broad, and may include more drastic transformations, such as the reduction of ore to metal (for which see Refining (metallurgy)). The refining of liquids is often accomplished by distillation or fractional distillation, fractionation; this process is useful, for example, for isolating different fractions of petroleum. Gases can be refined in this way as well, by being cooled and/or compressed until they liquefy. Gases and liquids can also be refined by solvent extraction, extraction with a selective solvent that dissolves away either the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Induction Motor
An induction motor or asynchronous motor is an AC motor, AC electric motor in which the electric current in the rotor (electric), rotor that produces torque is obtained by electromagnetic induction from the magnetic field of the stator winding. An induction motor therefore needs no electrical connections to the rotor. An induction motor's rotor can be either wound rotor motor, wound type or squirrel-cage rotor, squirrel-cage type. Three-phase Squirrel-cage rotor, squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable, and economical. Single-phase electric power, Single-phase induction motors are used extensively for smaller loads, such as garbage disposals and stationary power tools. Although traditionally used for constant-speed service, single- and three-phase induction motors are increasingly being installed in variable-speed applications using variable-frequency drives (VFD). VFD offers energy savings opportunities for i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utility Frequency
The utility frequency, (power) line frequency (American English) or mains frequency (British English) is the nominal frequency of the oscillations of alternating current (AC) in a wide area synchronous grid transmitted from a power station to the end-user. In large parts of the world this is 50 Hz, although in the Americas and parts of Asia it is typically 60 Hz. Current usage by country or region is given in the list of mains electricity by country. During the development of commercial electric power systems in the late-19th and early-20th centuries, many different frequencies (and voltages) had been used. Large investment in equipment at one frequency made standardization a slow process. However, as of the turn of the 21st century, places that now use the 50 Hz frequency tend to use 220–240 V, and those that now use 60 Hz tend to use 100–127 V. Both frequencies coexist today (Japan uses both) with no great technical reason to prefer one ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mains Electricity
Mains electricity, utility power, grid power, domestic power, wall power, household current, or, in some parts of Canada, hydro, is a general-purpose Alternating current, alternating-current (AC) electric power supply. It is the form of electrical power that is delivered to homes and businesses through the electrical grid in many parts of the world. People use this electricity to power everyday items (such as domestic appliances, televisions and lamps) by plugging them into a wall outlet. The voltage and utility frequency, frequency of electric power differs between regions. In much of the world, a voltage (nominally) of 230 volts and frequency of 50 Hz is used. In North America, the most common combination is 120 V and a frequency of 60 Hz. Other combinations exist, for example, 230 V at 60 Hz. Travellers' portable appliances may be inoperative or damaged by foreign electrical supplies. Non-interchangeable AC power plugs and sockets, plugs and sock ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweden
Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic country by both area and population, and is the List of European countries by area, fifth-largest country in Europe. Its capital and largest city is Stockholm. Sweden has a population of 10.6 million, and a low population density of ; 88% of Swedes reside in urban areas. They are mostly in the central and southern half of the country. Sweden's urban areas together cover 1.5% of its land area. Sweden has a diverse Climate of Sweden, climate owing to the length of the country, which ranges from 55th parallel north, 55°N to 69th parallel north, 69°N. Sweden has been inhabited since Prehistoric Sweden, prehistoric times around 12,000 BC. The inhabitants emerged as the Geats () and Swedes (tribe), Swedes (), who formed part of the sea-faring peopl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
