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NOTES OF LESSON
CE2303 Railways, Airport and Harbour Engineering













The Definition of Railway Rolling Stock
It is always useful at the outset of consideration of a subject to pause for a moment and to ponder the definitions, attributes range and scope of the matter.
Rolling stock used on railways in the earliest days evolved from carriages and wagons which ran on highways to carry both people and bulk materials.
As early as the sixteenth century wooden wheeled carts were used in mines and quarries running on longitudinal timber rails. With the progressive evolution of the skills and crafts of the wheelwright, metalworker and the ironmaker, wheels improved through various phases from simple rough
turned wooden spools through spoked and rimmed construction to fully cast and turned metal wheels.
Similarly, body construction and springing, particularly for passenger carrying vehicles, relied very heavily on the experience gained in the construction of stagecoaches in the seventeenth and eighteenth centuries. At the end of the eighteenth century, horse drawn trams running on metal rails began to appear in a number of European cities. These horse drawn tramways were literally to pave the way for development of railways when steam power began to be developed early in the 1800s. One has only to look at illustrations of early passenger coaches to see how closely they resemble
the road vehicles of the previous century.
As railway experience was gained, the design of rolling stock also evolved. Springing, body structure, wheels and axles all are subject to varying loads and stresses, when comparing slower speeds on rough roads to much faster speeds on railways, with a comparatively smoother ride.
Railway rolling stock generally runs on hard wheels on hard rails. The wheels are not only supported by the rails but are guided by them. The only exception to this is for a small number of metros where rubber tyres have...