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Tractors
A tractor is a type of vehicle that is particularly constructed to efficiently deliver a tractive effort at a slow speed. The word tractor was taken from a Latin word that means “to pull”. Tractors are special vehicles which are aimed to provide the hauling of trailers and other types of machinery which are used for agricultural and construction purposes. Farm tractors first made their appearance in the nineteenth century. The earliest ones had steam-powered portable engines. These were followed by oil-burning and then gasoline-powered tractors. The steam powered engines were in use until the onset of the 20th century, when they were replaced by more reliable internal combustion engines. A farm tractor is a distinctive, multi-purpose farm vehicle. It is perhaps the most essential of all farm machinery. Farm tractors are used to carry out different agricultural tasks: pulling or pushing machines and trailers for tilling, plowing, harrowing, planting, disking, transporting and providing power supply and other tasks. A variety of specialized farm tractors have been developed for particular uses. Farm tractors may be divided into two groups: wheeled and track-laying. Wheeled tractors may be subdivided into standard and row-crop types. Standard wheeled tractors are used for general work and do not have the special features associated with row-crop tractors. Row-crop tractors can be used for all ordinary purposes, but in addition they are specially designed for working on root and other row crops. The tractor can pass down rows of corn, tomatoes or other crops without crushing the plants. Track-laying tractors or crawlers have the great advantage that they can be used for heavy loads on almost any class of land. They are considerably more economical in fuel than are wheel machines, but their greater initial cost and their maintenance particularly that of the tracks, may outweigh this advantage. The crawler is, however, the more efficient type of tractor and, moreover, can go on the land earlier after rain and so can work a greater number of days per year. Modern farm tractors may have eight-wheel drive unit, caterpillar tracks, or articulated or non-articulated tracks, electrical or computer controls and are capable of multitude of different functions. Many modern farm tractors are fitted with GPS devices, auto-steer systems and other automated features. Modernized tractors may also have cabs accessorized with heated seats, automatic temperature controls, and dashboard computers. Tractors offer a lot of use and convenience for many people. Tractors are also usually associated with farm machines and general farm use. However, there is a common misconception that they can only be found on farms. In addition to pulling implements like plows and cultivators a tractor may be used for bush-cleaning, ditch filling and land-leveling. Small tractors from one to ten horse power with single or twin cylinder petrol engines may be used for garden and orchard work.
Text C Date: 2015-05-09; view: 993; Нарушение авторских прав |