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Handpumps

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→‎Construction, operations and maintenance

There are many different types of handpumps. However most of them are positive displacement pumps and have reciprocating pistons or plungers. There are suction pumps, low lift pumps, direct action pumps, intermediate life pumps, and high lift pumps. For details on these types, look them up in [http://www.wateraid.org/uk/what_we_do/sustainable_technologies/technology_notes/244.asp Technology notes] (by WaterAid).

Direct action handpumps , for example, are usually made of PVC and other plastics, and are installed on boreholes of limited depth. A plunger is attached to the lower end of a pump rod, beneath the groundwater level. The user moves the pump rod in an up-and-down motion, using a T-bar handle. On the up-stroke, the plunger lifts water into the rising main, and replacement water is drawn into the cylinder through the foot valve. On the down- stroke, the foot valve closes, and water passes through a one-way valve in the plunger and is lifted on the next upstroke.

Because direct action handpumps have no mechanical advantage, such as the lever or fly-wheel of a deep-well handpump, direct action pumps can only be used to depths from which an individual can physically lift the column of water (about 12 m). However, the mechanical simplicity, low cost and lightweight construction makes these pumps well equipped to meet O&M objectives at the village level.

Winona

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