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![[image of flower]](../../ima/flowXS_06.gif)
Mining, Excavating and Construction Machinery |
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These industries require removing and transporting large amounts of heavy materials quickly and effortlessly. Before steam and electrical power provided heavy machinery and vehicles, they relied mainly on the muscle power of man and beast. At this time, mining and excavating was done entirely with hand tools, as it was since ancient times. Picks, shovels and hand carts moved by animal or human muscle prevailed. William S. Otis (1813-1839), an American, invented the first powered construction machine, the steam shovel in in 1835. Tthe machine was patented in 1839 (1841 version). The Otis Shovel is the predecessor of all construction machines and became the foundation for mechanized construction. Most of Otis’ principles are still used in construction equipment today. The Otis Shovel was composed of a crane mounted on a carriage. A load of earth could be taken up by a scraper and raised by the crane, which could then turn to dump the contents in railcars or other transportation vessels. A steam engine was installed with a power control mechanism for the crane, together with a system of pulleys to move its arms and bucket. Technological descendants of the Otis Shovel soon became key to large-scale surface mining of coal, iron ore, uranium, and oil sands. Cleveland The Amoskeag Company of Manchester, NH, patents a steam pumper engine in 1873. In 1890, a patent for a pneumatic hammer was issued to Charles B. King. Carruth 355 Bulldozers, modified crawler tractors that appeared in the 1920s, began to appear. They had a pushing blade wider than the tractor and a curved at the top to roll the earth forward and were located in front of the vehicle. How 374 Later, the crawler would feature a loader and a digger-loader. |
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