Pumping machinery; a practical hand-book relating to the construction and management of steam and power pumping machines, with upwards of 260 ... every essential detail in pump construction - Softcover
Synopsis
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. 1893 Excerpt: ... pressure and the ratio of expansion. Noncondensing steam-ends are not recommended for pressures below 50 pounds, as there will not be a saving sufficient to warrant the additional cost of the machinery, v Tandem Direct-Acting Compound Steam-End.--The high-pressure cylinder is supposed to take its steam directly from the boiler and admitted at the same pressure. Practically this is seldom the case, and from 5 to 10 pounds less than boiler-pressure is the ordinary available pressure. It is not a general practice to supply receivers or tanks with ordinary compound duplex pumps. The high-and lowpressure cylinders are placed tandem to each other, with both pistons attached to the same rod, as shown in Fig. 180. The exhaust from the high-pressure cylinder passing directly into the low-pressure steam-chest, and from thence into the lowpressure cylinder. The slide-valves of both cylinders have the same movement, the ports being of equal dimensions in the direction of valve travel. The valves having neither lap nor lead, the steam and exhaust are operated at full stroke in both cylinders. The pressure of steam in the low-pressure steam-chest will be variable, depending on the distance which the pistons have travelled towards the end of the stroke. In this design the low-pressure cylinder is fitted with tierods connecting it with the water-end; a substantial cast-iron foot or base under the cylinder affords support for carrying the weight of the entire steam-end, as it is not a common practice to provide the high-pressure cylinder with any means of support other than the end flanges connecting it with the intermediate head. For small pumping engines it is the practice to have the high-and low-pressure valve-seats in the same plane, both valves being driven by the sa...
"synopsis" may belong to another edition of this title.
