A history of the growth of the steam-engine . e-wheelpropulsion. In the latter methods these losses amount toan important fraction of the total power; they rarely, ifever, fall below a total of 25 per cent., and probably intowage exceed 50 per cent. The objection to the adoptionof chain-propulsion, as it is also often called, is the necessityof following closely the line along which the chain or therope is laid. There is, however, much less difficulty than MARINE ENGINES. 403 would be anticipated in following a sinuous route or inavoiding obstacles in the channel or passing other s
A history of the growth of the steam-engine . e-wheelpropulsion. In the latter methods these losses amount toan important fraction of the total power; they rarely, ifever, fall below a total of 25 per cent., and probably intowage exceed 50 per cent. The objection to the adoptionof chain-propulsion, as it is also often called, is the necessityof following closely the line along which the chain or therope is laid. There is, however, much less difficulty than MARINE ENGINES. 403 would be anticipated in following a sinuous route or inavoiding obstacles in the channel or passing other system is particularly well adapted for use on canals. The steam-boilers in use in the later and best marineengineering practice are of various forms, but the standardtypes are few in number. That used on river-steamers inthe United States has already been described. Fig. 142 is a type of marine tubular boiler which is inmost extensive use in sea-going steamers for moderatepressure, and particularly for naval vessels. Here the gases P4 * mfj^. Re. 142.—Marine Fire-tubular Boiler. Section. pass directly into the back connection from the fire, andthence forward again, through horizontal tubes, to the frontconnection and up the chimney. In naval vessels the steam-chimney is omitted, as it is there necessary to keep all partsof the boiler as far below the water-line as possible. Steamis taken from the boiler by pipes which are carried fromend to end of the steam-space, near the top of the boiler,the steam entering these pipes through small holes drilledon the other side. Steam is thus taken from the boiler wet, but no large quantity of water can usually be en-trained by the steam. A marine boiler has been quite extensively introduced 404 THE STEAM-ENGINE OP TO-DAY. into the United States navy, in which the gases are ledfrom the back connection through a tube-box around andamong a set of upright water-tubes, which are filled withwater, circulation taking place freely from the water
Size: 1865px × 1340px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, bookidc, booksubjectsteamengines
