Io l'inglese lo so...e ho capito!
Cmq...grazie Daniele come sempre !!!!! Adesso sì che ci sono!!!!!!!!
Guardate un pò qui, ho trovato altre info:
Da Wikipedia!
The walking beam, also known as an "overhead beam" or simply "beam", was another early adaptation of the beam engine, but its use was confined almost entirely to the United States. After its introduction,
the walking beam quickly became the most popular engine type in America for inland waterway and coastal service, and the type proved to have remarkable longevity, with walking beam engines still being occasionally manufactured as late as the 1940s. (
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In marine applications, the beam itself was generally reinforced with iron struts that gave it a characteristic diamond shape, although the supports on which the beam rested were often built of wood. The adjective "walking" was applied because the beam, which rose high above the ship's deck, could be seen operating, and its rocking motion was (somewhat fancifully) likened to a walking motion.
USS Delaware (1861). The vessel's diamond shaped "walking beam" can clearly be seen amidships
Walking beam engines were a type of paddlewheel engine and were rarely used for powering propellers. They were used primarily for ships and boats working in rivers, lakes and along the coastline, but were a less popular choice for seagoing vessels because the great height of the engine made the vessel less stable in heavy seas.
They were also unsuitable for military use, because the engine was exposed to enemy fire and could thus be easily disabled. Their popularity in the United States was due primarily to the fact that the walking beam engine was well suited for the shallow-draft boats which operated in America's shallow coastal and inland waterways.
Walking beam engines remained popular with American shipping lines right to the end of the 19th century. The Philadelphian shipbuilder Charles H. Cramp blamed America's general lack of competitiveness with the British shipbuilding industry in the mid-to-late 19th century upon the conservatism of American domestic shipbuilders and shipping line owners, who doggedly clung to outdated technologies like the walking beam and its associated paddlewheel long after they had been abandoned in other parts of the world.
Un paio di immagini:
http://en.wikipedia.org/wiki/File:Walki ... engine.jpghttp://en.wikipedia.org/wiki/File:USS_D ... 861%29.jpgE un video:http://www.youtube.com/watch?v=pUDQYzE9gcM