Bulletin of the International Railway Congress Association Volume 25
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1911 edition. Excerpt: ...in practice. The use in all three systems of a portion of the exhaust steam is virtually equivalent to an enlargement of the blast-pipe. This results in a softer blast, which, however, is not detrimental, on account of the reduction in the amount of work the boiler is called upon to do. The softer blast lias the effect of materially reducing the loss by unburnt coal, while a thinner and more efficient fire can be maintained without risk of lifting it off the grate, or of drawing air through holes. At the rate of firing common in express working the losses by unburnt coal passing to the smoke-box and out of the chimney, and dropping through the grate, frequently reaches, as shown by the St. Louis and other tests, 20 per cent or more of the coal fired, so that it is not unreasonable to suppose that the balance of 6 per cent may actually be traced in this direction. We arc not possessed of statistics relating to this point with regard to the Drummond and (iaines systems, but facts relating to the Trevithick system show that a great part, if not all, of this additional (i per cent economy is due to a reduction in the losses of unburnt coal. gives a value for W of 9-496. The amount of water to be evaporated in this case for every 1 lb. of steam used in the cylinders would thus be 1 105 11. from a temperature of 280" Fahr., and for this 1,049 B. T. U. would be needed. This system shows, therefore, a saving of 111 B. T. U., or 9 56 per cent over the ordinary injector. It may be noted that in another form of exhaust injector the amount of live steam used is much smaller than that in the type taken above. The temperatures obtained are such, however, that the over-all saving remains the same. In a third class of feed-water beating appliances...
- 189 x 246 x 35mm | 1,207g
- 13 Sep 2013
- United States
- black & white illustrations