Proceedings of the Engineers' Club of Philadelphia Volume 31 (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. 1914 Excerpt: ... to the hot well is reclaimed, and the highest possible vacuum is obtained. Even where a large supply of fresh water is available for boiler feed, the majority of situations are such that feed water has to be treated in some way before it is fit to use. The all-important question of pure feed water is therefore practically independent of whether the condensing water supply is fresh or salt, and favors the use of surface condensers particularly as the proportion of make up water required to replenish the losses in a well operated station should not exceed 5 to 8%. The question of condenser tube corrosion seems to have narrowed down to a search for an alloy of high heat conductivity which is not deteriorated by the treatment it receives during manufacture, and is not subject to local galvanic action between particles of the different metals in its composition, and is not affected by the presence of impurities in the condensing water. In a turbine there is no waste from cylinder condensation. The steam can be expanded to a much greater volume and consequently lower pressure than is physically possible in an engine. Consequently, the development of the turbine has caused a correspondent improvement in the condenser. The practical limit of vacuum possible with piston engines will average about 2C inches (formerly it was much less) while with turbines 28 inches has been easily attainable for some years and now the latest standard specifications call for 29 inches. This makes possible a considerable gain over engine practice 'n the conversion of heat into work. The ratio of circulating water to steam condensed, for a turbine, is two to three times that of a piston engine. The cooling surface in the condenser of the 25,000 K. W. Parsons tuibine in Chicago is a litt...