Читать книгу Locomotive Engine Running and Management онлайн

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The observing engineer of any experience does not require to have the advantages of working his engine expansively impressed upon his attention. His fuel-record has done that more eloquently than pen can write.

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There is a close and constant relation between the boiler pressure carried, and the useful work obtained from expansion of steam. The higher the pressure, the greater elasticity the steam possesses. The tendency of modern steam engineering is, to employ intensely high boiler pressure, expanding the steam by means of excellent valve-gear in steam-jacketed cylinders, so that it is reduced to low tension before escaping into the atmosphere, or into the condenser, as the case may be. Wonderfully economical results have been obtained in this manner,—results which can never be approached in locomotive practice while the ordinary slide-valve is used. But, while we can not hope to rival the record of high-class automatic cut-off engines, their methods can teach us useful lessons.