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Debarking (lumber)
Debarking is the process of removing bark from wood. Traditional debarking is conducted in order to create a fence post or fence stake which would then go on to be pointed before being planted. Debarking can occur naturally during powerful tornadoes, such as the 2013 Moore tornado. Process Debarking generally involves the use of industrial machinery into which the log or stake is placed. These machines can be either stationary or portable. Generally they are powered by hydraulic motors but can also be driven by a power take-off. The log or stake is then pressed against blades or knives which remove the bark while the log is turned to ensure the removal of bark from all around the log. Debarking can also take place by hand, although this can be very time consuming and may not be suitable for large volumes. Side-streams from debarking Bark is the usual side-stream produced during log debarking. In several wood-related industries, such as plywood, veneer and laminated veneer indu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bark (botany)
Bark is the outermost layer of Plant stem, stems and roots of woody plants. Plants with bark include trees, woody vines, and shrubs. Bark refers to all the Tissue (biology), tissues outside the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner bark, which in older Plant stem, stems is living tissue, includes the innermost layer of the periderm. The outer bark on older stems includes the dead tissue on the surface of the stems, along with parts of the outermost periderm and all the tissues on the outer side of the periderm. The outer bark on trees which lies external to the living periderm is also called the Glossary of botanical terms#rhytidome, rhytidome. Products derived from bark include bark shingle siding and wall coverings, spices, and other flavorings, tanbark for tannin, resin, latex, medicines, poisons, various hallucinogenic chemicals, and Cork (material), cork. Bark has been used to make clot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Wood
Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include the same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree, it performs a mechanical-support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients among the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips, or fibers. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Tornado
A tornado is a violently rotating column of air that is in contact with the surface of Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the word cyclone is used in meteorology to name a weather system with a low-pressure area in the center around which, from an observer looking down toward the surface of the Earth, winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Tornadoes come in many shapes and sizes, and they are often (but not always) visible in the form of a funnel cloud, condensation funnel originating from the base of a cumulonimbus cloud, with a cloud of rotating debris and dust beneath it. Most tornadoes have wind speeds less than , are about across, and travel several kilometers (a few miles) before dissipating. The Tornado records#Highest winds observed in a tornado, most extreme tornadoes can attain wind speeds of mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
2013 Moore Tornado
The 2013 Moore tornado was a large and extremely violent EF5 tornado that ravaged Moore, Oklahoma, and adjacent areas on the afternoon of May 20, 2013, with peak winds estimated at , killing 24 people (plus two indirect fatalities) and injuring 212 others. The tornado was part of a larger outbreak from a slow-moving weather system that had produced several other tornadoes across the Great Plains over the previous two days, including five that had struck portions of Central Oklahoma the day prior on May 19. The tornado, along with the 2011 Hackleburg–Phil Campbell and El Reno–Piedmont tornadoes, has the highest rated official windspeed on the Enhanced Fujita scale, if the upper range is considered. The tornado touched down just northwest of Newcastle at 2:56 p.m. CDT (19:56 UTC), and quickly became violent, persisting for 39 minutes on a path through a heavily populated section of Moore, causing catastrophic damage of EF4 to EF5 intensity, before diss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Power Take-off
A power take-off or power takeoff (PTO) is one of several methods for taking power from a power source, such as a running engine, and power transmission#Mechanical power, transmitting it to an application such as an attached implement or separate machine. Most commonly, it is a spline (mechanical), splined drive shaft installed on a tractor or truck allowing implements with mating fittings to be powered directly by the engine. Semi-permanently mounted power take-offs can also be found on industrial and marine engines. These applications typically use a drive shaft and bolted joint to transmit power to a secondary implement or accessory. In the case of a marine application, such as shafts may be used to power fire pumps. In aircraft applications, such an accessory drive may be used in conjunction with a constant speed drive. Jet aircraft have four types of PTO units: internal gearbox, external gearbox, radial drive shaft, and bleed air, which are used to power engine accessories. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hydraulic Debarker
A hydraulic debarker is a machine removing bark from wooden logs by the use of water under a pressure of or greater. Hydraulic debarking can reduce soil and rock content of bark, but may increase the water content. Debarking water may be recycled after effective settling, but suspended solids may increase wear on high-pressure pumps. Hydraulic debarking has declined where water quality problems have arisen. History Bark on mature redwood trees of coastal California can vary from in thickness. Redwood bark is thick, stringy and tough; and can cause sawmill machinery to malfunction. Men called peelers removed bark from fallen trees in the woods through the early 20th century, but the process was dangerous and labor intensive. In the mid-20th century hydraulic barkers were built at several large sawmills including the Union Lumber Company at Fort Bragg, California, the Northern Redwood Company at Korbel, and the Pacific Lumber Company at Scotia, California. The last was feat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Girdling
Girdling, also called ring-barking, is the circumferential removal or injury of the bark (consisting of cork cambium or "phellogen", phloem, cambium and sometimes also the xylem) of a branch or trunk of a woody plant. Girdling prevents the tree from sending nutrients from its foliage to its roots, resulting in the death of the tree over time, and it can also prevent flow of nutrients in the other direction depending on how much of the xylem is removed. A branch completely girdled will fail; and, when the main trunk of a tree is girdled, the entire tree will die if it cannot regrow from above to bridge the wound. Human practices of girdling include forestry, horticulture, and vandalism. Foresters use the practice of girdling to thin forests. Extensive cankers caused by certain fungi, bacteria or viruses can girdle a trunk or limb. Animals such as rodents will girdle trees by feeding on outer bark, often during winter under snow. Girdling can also be caused by herbivorou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
