Practical irrigation and pumping; water requirements, methods of irrigation and analyses of cost and profit

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. 1915 Excerpt: ...centrifugal. If the total head is less than 70 to 100 feet the single-stage pump should be used, but for greater heads the necessary speed of the single-stage pump will be excessive for successful and longcontinued operation and a multiple stage should be used. Where electrical power is available at reasonable cost a pump direct connected to a motor will be found most convenient. If a gasoline engine is used, it should be selected of a make known to be reliable. Some suggestions on this point will be found in Chapter XIII. Plant No. 2 The pumping plant shown in Fig. 25 is of a type very common in those sections of the West where water is found at shallow depths, as in river valleys immediately adjacent to streams, and water is pumped either to supplement a gravity supply or is used by some fruit or truck grower for an independent and dependable water supply. Pump Pit and Arrangement of Belt Drive.--In such a plant an open pit 6 to 8 feet square or round is first dug to water and lined with timber or in some cases with concrete. Owing to the use in this case of an inclined belt reaching from the engine at the surface to the horizontal centrifugal pump in the pit, such pits are limited to a depth of about 25 feet. With greater depths it is not feasible to use the inclined belt, owing to its excessive length. It might be suggested that in order still to use the horizontal pump with deeper pits, a counter-shaft could be placed across the top of the pit from which a vertical belt might extend to the pump. This has, however, a serious disadvantage in the use of the vertical belt, which seldom works satisfactorily, besides which there is a loss of power in the use of the countershaft and two belts instead of one. With the inclined belt, the sag of the belt increas...