MICROFICHE REFERENCE LIBFUUW - Cd3wd.com

112such variables as impeller size, number of stages, drive speed,, etc., thesebasic designs can be made to fit any intermediate conditions. While themanufacture of the complex vertical turbine and submersible pumps ispresently limited to several companies in indistrial nations, volute andpropeller pumps are easily manufactured by the basic industries (e.g.foundries) in developing countries (Ahmad, 1969). In fact, a 1961 SEATOthesis by Srisakdi Charmonman explains the design, construction, and performanceof an axial--flow pump made quite simply by encasing the propellerof a Thai-style outboard motor (3-l/2-7 hp.) with a cylinder. As illustratedin Figure 4.6, this design permits dual use of the motor for both boat andpump motivation. This pump can be utilized with the anchored boat as afoundation (Figure 4.6b) or dismounted and used on shore (Figure 4.6~).This improvisation provides the simple low head, high discharge pumprequired for the irrigation and drainage of crops such as rice in lowlandareas. Commercial units of this design are reported to be manufactured inJapan for about $300 (Bowers, 1975) .Initial costs of rotodynamic pumps very greatly, depending on thetype, size, power, materials of construction, and manufacturer. Many pumpsalso require numerous accessories and/or sophisticated foundations andinstallation, manufacturers’ catalogs and/or well contractors must beconsul ted. However, as a rough guide, a buyer can expect to pay (forpump only) up to $500 for sizes under 1 hp, $100-500 per hp up to i0 hp,and $100-400 per hp above 10 hp, with cost per hp decreasing for increasinghorsepower (based on 1974-75 U. S. manufact.urers’ catalogs of new pumps).