Permanent Way, Rolling Stock and Technical Working of Railways Volume 2 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1878 Excerpt: ... we see, may reach for a certain number of these axles, higher figures still. I regret not being able to push further this verification of maximum distances run, as it would be so useful and so instructive, if the figures of the sources of supply and of the conditions of manufacture, were compared. However what precedes will no doubt be sufficient to call the attention of the companies to this point. V.--wheels. aos. The wheels of engines differ from waggon wheels by their diameter, always greater, and often a great deal more; by their more solid constitution, in accordance with the considerable load which they support; and, if required, by the existence of a crank or cranks and a counterweight (278 and following). For a long time the centre was formed as it is often still (104) in waggons, of cast iron SDokes mandrilled and fixed in a cast iron boss. This method is given up. Although formed of T iron, the spotes gave too much, and the tyre got loose. On the other hand the heavy cast iron bosses were bound to disappear as soon as a reduction of weight became absolutely indispensable. Engine wheels are thus of wrought iron, and sometimes of steel. It is only in the United Stated, that cast iron is prefered for engine wheels, as well as for waggon wheels as we have seen (108). If we seek what is special in the conditions to which the driving wheel is subjected, we immediately find that it acts at the same time as a carrying wheel, and as a pulley with a cord wound round it with a tension equal to the effort of traction, or the tangentical reaction of the rails on the tyre. Each of the spokes is then a solid compressed along its axis, solidly fixed at one end to the boss, and solicited at the free end by a normal force, equal to the effort of traction d...