[[Image:== Rope/elephant_pump_icon.png|right]]elephant pump==
For wells down to 35 m, rope pumps are often 5 times cheaper and more Rotating movement (constant force 5-10 Kg.m) sustainable than piston pumps. Evaluations show that rope pumps on communal wells are being maintained by the users, if introduced properly. 90% Of rope pumps remain operational, even after many years. Continous water flow Because of its low cost, the pump is also popular for domestic use. (1-2 m/s) A survey among 5,025 rural families in Nicaragua indicates that a Schematic PVC pump tubes drawing of a rope pump increases income, even if used for domestic purposes (5-10 Kg) rope pump only. Families with a pump earn US$ 220 per year more than Low pressure in all parts families without a pump. In Nicaragua the pumps are now being (0, Kg/cm) produced commercially by 20 workshops. Few, non-corroDifferent models of Rope pumps were introduced in Africa.This sive pump parts introduction has not always been successful: in some projects over 80% of the pumps do NOT work! However, with the "right" models and the "right" user training, also 90 % remain in operation in Africa, as the Victory model in Ghana and the Elephant model in Zimbabwe have proved. [[Image:Rope/Elephant_pump.PNG|thumb|right|150px|[* See [Rope/Elephant pump |Rope/Elephant pump ]], in Epworth (for credits, click the picture)]] {| border="1" cellpadding="5" cellspacing="0" align="center"|-! width="50%" style="background:#efefef;" | Advantages! style="background:#ffdead;" | Disadvantages|-| valign="top" | Significantly cheaper than piston pumps.<br>Easy to maintain.<br>Easy to train on maintenance.| valign="top" | Not all introduction programs have been successful.<br>|} == Capacity == 40 litres / min from 10 meters depth. == Costs == * US$ 20-120 depending on model. == Applying conditions ==<ul><li><b>Numbers:</b> 50,000 in Nicaragua, 20,000 in Mexico, Honduras, Guatemala, Ghana, Zimbabwe, Tanaznia, Senegal.</li><li><b>Yield:</b> 40 litres/min from 10 m depth.</li><li><b>Range of depth:</b> 1-35 meter (60 m with two cranks).</li><li><b>Application</b> Communal wells, houshold, irrigation. </li><li><b>Initial cost:</b> US$ 20-120 depending on model.</li><li><b>Cost of introduction:</b> US$ 10,000-20,000 per project, including 20 pumps, engineering and hands-on training. US$ 60,000-100,000 per project, including 1,000 pumps, production workshop and hands-on training.</li></ul> == External links ==* Evaluations [http://www.irc.nl www.irc.nl ]* Africa [http://www.pumpaid.org www.pumpaid.org ]* General info [http://www.ropepump.com www.ropepump.com] * How to build [http://www.ropepumps.org www.ropepumps.org]