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Handpumps

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Many different kinds of handpumps are frequently installed on hand-dug wells and boreholes in rural areas, including many drought-prone areas. They facilitate a contamination-free method to extract water. Most pumps 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: Handpumps] (by WaterAid).
====Reciprocating handpumps====
The majority of handpump types used worldwide belong to the group of reciprocating pumps. The water is lifted by a piston that is raised and lowered inside a cylinder that has a footvalve. The piston (or plunger) is moved by a pump rod connected directly to a T-handle or a lever handle at the pump head. In some pump types, a flywheel with crankshaft is used to create the reciprocating movement of the piston.
The function of the reciprocating pumps is based on the principle that water flows from areas of high pressure to areas of low pressure. The reciprocating pump creates an area of sufficiently low pressure above the body of water, causing it to flow upward.
'''====Suction pumps'''<br> ====
In a suction pump, the cylinder is above the water table, usually near the top of the pump head. The rising main extends below the water table. When the pump is operated, during the upwards stroke it appears that water gets “sucked up” through the rising main into the cylinder. In fact, the atmospheric pressure forces the water into the area of low pressure underneath the piston. The theoretical limit to which the atmospheric pressure can push up water is 10 metres (m). In practice, suction pumps can be used to lift water up to about 7 or 8 m.
Examples of suction pumps include: [[No. 6 pump]], [[Rope pump]], [[Rower pump]], [[Treadle pump]], [[Super MoneyMaker pump]], and [[MoneyMaker hip pump]].
'''====Direct Action handpump'''<br>====
[[Image:DirectActionHandpump.jpg|thumb|right|300px| Direct action handpump mechanics. Drawing: WHO.]]
Examples of the Direct Action handpump: [[Tara pump]], [[Malda pump]], [[Nira AF-85 pump]], [[Canzee pump]], [[EMAS pump]], and the [[PVC pumps]] has a direct action version.
'''====Lever Action handpump'''<br>====
Most deep-well handpumps are of the lever action type. The increased length of the water column in deep boreholes requires more effort to draw water and the lever of the handle makes the operation easier. Besides the conventional handle, there are also pump designs, which use a flywheel to operate a crankshaft for transforming the rotation into an up-and-down movement.
Examples of a Lever Action pump include: [[Kabul pump]], [[Jibon pump]], [[Walami pump]], [[U3M pump]], [[Afridev pump]], [[Afridev with bottom support]], [[Indus pump]], [[Pamir pump]], [[India Mark 2 and 3]], and the [[Bush pump]].
====Rotary handpumps====
The most commonly used rotary handpumps are the [[rope pump]] and the progressive cavity pump (very difficult for local technicians to maintain). Note that although some reciprocating pumps use a circular action mechanism to drive the pistons, they are not categorized as rotary.
====Diaphragm pumps====
[[Deep-well_diaphragm_pump|Diaphragm pumps]] are pumps employing a flexible diaphragm that is expanded and contracted to displace water. The advantages of diaphragm pumps are that they are easy to install, because no heavy mechanical parts are used. They can also be made corrosion-resistant through the use of plastic
hoses instead of metallic rising mains.
Example of a diaphragm pump: [[Vergnet Hydro]]
====Piston / Suction handpump====
 
====Lever Action handpump====
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