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Trencher (machine)
A trencher is a piece of construction equipment used to dig trenches, especially for laying pipes or electrical cables, for installing drainage, or in preparation for trench warfare. Trenchers may range in size from walk-behind models, to attachments for a skid loader or tractor, to very heavy tracked heavy equipment. Types Trenchers come in different sizes and may use different digging implements, depending on the required width and depth of the trench and the hardness of the surface to be cut. Wheel trencher A wheel trencher or rockwheel has a toothed metal wheel. It is cheaper to operate and maintain than chain-type trenchers. It can work in hard or soft soils, either homogeneous (compact rocks, silts, sands) or heterogeneous (split or broken rock, alluvia, moraines). This is particularly true because a cutting wheel works by clearing the soil as a bucket-wheel does, rather than like a rasp (chain trencher). Consequently, it will be less sensitive to the presence of b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Marais Wheel Trencher In Sout Africa
A, or a, is the first Letter (alphabet), letter and the first vowel letter of the Latin alphabet, used in the modern English alphabet, and others worldwide. Its name in English is ''English alphabet#Letter names, a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version is often written in one of two forms: the double-storey and single-storey . The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English, ''English articles, a'' is the indefinite article, with the alternative form ''an''. Name In English, the name of the letter is the ''long A'' sound, pronounced . Its name in most other languages matches the letter's pronunciation in open syllables. History The earliest know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel
Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength and low raw material cost, steel is one of the most commonly manufactured materials in the world. Steel is used in structures (as concrete Rebar, reinforcing rods), in Bridge, bridges, infrastructure, Tool, tools, Ship, ships, Train, trains, Car, cars, Bicycle, bicycles, Machine, machines, Home appliance, electrical appliances, furniture, and Weapon, weapons. Iron is always the main element in steel, but other elements are used to produce various grades of steel demonstrating altered material, mechanical, and microstructural properties. Stainless steels, for example, typically contain 18% chromium and exhibit improved corrosion and Redox, oxidation resistance versus its carbon steel counterpart. Under atmospheric pressures, steels generally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geotextile
Geotextiles are versatile permeable fabrics that, when used in conjunction with soil, can effectively perform multiple functions, including separation, filtration, reinforcement, protection, and drainage. Typically crafted from polypropylene or polyester, geotextile fabrics are available in two primary forms: woven, which resembles traditional mail bag sacking, and nonwoven, which resembles felt. Geotextile composites have been introduced and products such as geogrids and meshes have been developed. Geotextiles are durable and are able to soften a fall. Overall, these materials are referred to as geosynthetics and each configuration—geonets, geosynthetic clay liners, geogrids, geotextile tubes, and others—can yield benefits in geotechnical engineering, geotechnical and environmental engineering design. History Geotextiles were originally intended to be a substitute for granular soil filters. Geotextiles can also be referred to as ''filter fabrics''. In the 1950s, R.J. Barr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of The Russian Invasion Of Ukraine (8 June 2023 – 31 August 2023)
This timeline of the Russian invasion of Ukraine covers the period from 8 June 2023, when the 2023 Ukrainian counteroffensive began, to 31 August 2023. June 2023 8 June Several newspapers and analysts reported that Ukraine's counteroffensive had begun, with the Institute for the Study of War noting that activity throughout Ukraine was consistent with a variety of indicators that counteroffensive operations were underway across the theater. In the early hours of the counteroffensive, the Armed Forces of Ukraine suffered "significant losses" according to US officials and the Ministry of Defence (Russia), Russian Ministry of Defence, but seemingly managed to break some lines of defence in Zaporizhzhia Oblast. According to US officials, the losses were not expected to impact Ukraine's counteroffensive as a whole. The Russian Defence Ministry said its forces had repelled an offensive by Ukrainian forces involving 1,500 soldiers and 150 armoured vehicles after a two-hour battle wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ukrainian Ground Forces
The Ukrainian Ground Forces (SVZSU, ), also referred to as the Ukrainian army, is a land force, and one of the eight Military branch, branches of the Armed Forces of Ukraine. It was formed from Ukrainian units of the Soviet Army after Declaration of Independence of Ukraine, Ukrainian independence, and its ancestry is traced back to the 1917–22 army of the Ukrainian People's Republic. After the dissolution of the Soviet Union in 1991, Ukraine retained its Soviet-era army equipment. The Armed Forces were systematically downsized and underinvested in after 1991. As a result, the Ukrainian army had very little of its Soviet equipment in working order by July 2014, and most systems had become antiquated. Personnel numbers had shrunk and training, command, and support functions needed improvement.In the Army Now: Answering Many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lawn Mower
A lawn mower (also known as a grass cutter or simply mower, also often spelled lawnmower) is a device utilizing one or more revolving blades (or a reel) to cut a lawn, grass surface to an even height. The height of the cut grass may be fixed by the mower's design but generally is adjustable by the operator, typically by a single master lever or by a mechanism on each of the machine's wheels. The blades may be powered by manual force, with wheels mechanically connected to the cutting blades so that the blades spin when the mower is pushed forward, or the machine may have a Battery (electricity), battery-powered or AC power plugs and sockets, plug-in electric motor. The most common self-contained power source for lawn mowers is a small four-stroke engine, 4-stroke (typically Single-cylinder engine, one-cylinder) internal combustion engine. Smaller mowers often lack any form of self-propulsion, requiring human power to move over a surface; "walk-behind" mowers are self-propelled, re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Breaker
A breaker is a powerful percussion hammer fitted to an excavator for demolishing hard (rock or concrete) structures. It is powered by an auxiliary hydraulic system from the excavator, which is fitted with a foot-operated valve for this purpose. Additionally, demolition crews employ the hoe ram for jobs too large for jackhammering or areas where blasting is not possible due to safety or environmental issues. Breakers are often referred to as "hammers", "peckers", "hoe rams" or "hoe rammers". These terms are popular and commonly used amongst construction/demolition workers. The first hydraulic breaker, Hydraulikhammer HM 400, was invented in 1967 by German company Krupp (today German company Atlas Copco) in Essen. Notable manufacturers See also * Excavator * Particulates Particulate matter (PM) or particulates are microscopic particles of solid or liquid matter suspension (chemistry), suspended in the atmosphere of Earth, air. An ''aerosol'' is a mixture of particu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excavator
Excavators are heavy equipment (construction), heavy construction equipment primarily consisting of a backhoe, boom, dipper (or stick), Bucket (machine part), bucket, and cab on a rotating platform known as the "house". The modern excavator's house sits atop an undercarriage with Caterpillar track, tracks or wheels, being an evolution of the steam shovel (which itself evolved into the power shovel when steam was replaced by diesel and electric power). All excavation-related movement and functions of a hydraulic excavator are accomplished through the use of hydraulic fluid, with hydraulic cylinders and hydraulic motors, which replaced winches, chains, and steel ropes. Another principle change was the direction of the digging action, with modern excavators pulling their buckets toward them like a dragline rather than pushing them away to fill them the way the first powered shovels did. Terminology Excavators are also called diggers, scoopers, mechanical shovels, or 360-degree ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chainsaw
A chainsaw (or chain saw) is a portable handheld power saw, power saw that cuts with a set of teeth attached to a rotating chain driven along a guide bar. Modern chainsaws are typically gasoline or electric and are used in activities such as tree felling, limbing, Log bucking, bucking, pruning, cutting firebreaks in wildland fire suppression, harvesting of Wood fuel#Firewood, firewood, for use in Chainsaw carving, chainsaw art and chainsaw mills, for cutting concrete, and cutting ice. Precursors to modern chainsaws were first used in surgery, with patents for wood chainsaws beginning in the late 19th century. A chainsaw comprises an engine, a drive mechanism, a guide bar, a cutting chain, a tensioning mechanism, and safety features. Various safety practices and working techniques are used with chainsaws. History In surgery A "flexible saw", consisting of a fine serrated link chain held between two wooden handles, was pioneered in the late 18th century (–1785) by two Scot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ditch Witch HT330 Track Trencher Stationary
A ditch is a small to moderate trench created to channel water. A ditch can be used for drainage, to drain water from low-lying areas, alongside roadways or fields, or to channel water from a more distant source for plant irrigation. Ditches are commonly seen around farmland, especially in areas that have required drainage, such as The Fens in eastern England and much of the Netherlands. Roadside ditches may provide a hazard to motorists and cyclists, whose vehicles may crash into them and get damaged, flipped over, or stuck and cause major injury, especially in poor weather conditions and rural areas. Etymology In Anglo-Saxon, the word ''dïc'' already existed and was pronounced ("deek") in northern England and "deetch" in the south. The origins of the word lie in digging a trench and forming the upcast soil into a bank alongside it. This practice has meant that the name ''dïc'' was given to either the excavation or the bank, and evolved to both the words "dike"/"dyke" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cemented Carbide
Cemented carbides are a class of hard materials used extensively for cutting tool material, cutting tools, as well as in other industrial applications. It consists of fine particles of carbide cemented into a composite material, composite by a binder metal. Cemented carbides commonly use tungsten carbide (WC), titanium carbide (TiC), or tantalum carbide (TaC) as the aggregate. Mentions of "carbide" or "tungsten carbide" in industrial contexts usually refer to these cemented composites. Most of the time, carbide cutters will leave a better surface finish on a part and allow for speeds and feeds, faster machining than high-speed steel or other tool steels. Carbide tools can withstand higher temperatures at the cutter-workpiece interface than standard high-speed steel tools (which is a principal reason enabling the faster machining). Carbide is usually superior for the cutting of tough materials such as carbon steel or stainless steel, as well as in situations where other cutting t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Speed Steel
High-speed steel (HSS or HS) is a subset of tool steels, commonly used as cutting tool material. Compared to high-carbon steel tools, high-speed steels can withstand higher temperatures without losing their temper (hardness), allowing use of faster cutting speeds. At room temperature, in their generally recommended heat treatment, HSS grades generally display high hardness (above 60 Rockwell C) and abrasion resistance compared with common carbon and tool steels. There are several different types of high speed steel, such as M42 and M2. History In 1868, English metallurgist Robert Forester Mushet developed Mushet steel, considered the forerunner of modern high-speed steels. It consisted of 2% carbon, 2.5% manganese, and 7% tungsten. The major advantage of this steel was that it hardened when air cooled from a temperature at which most steels had to be quenched for hardening. Over the next 30 years, the most significant change was the replacement of manganese with chromium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
