__NOTOC__<small-title />[[Image:ram_hydrolic_pump.jpg|right|80px]]
[[Image:PrincipleHydraulicRam.jpg|thumb|right|200px|Principle of a Hydraulic Ram pump.]]
[[Image:HydraulicRamChildren.jpg|thumb|right|200px|Children standing around a hydraulic ram pump. Photo: [http://www.ashden.org/media/international_photos/2007 AID Foundation, Phillippines.]]]
The hydraulic ram pump was invented in 1772 and widely used in the 19th century, but was side-tracked by the advent of the coal-powered steam engine and later by diesel powered pumps. In recent years the hydraulic ram pump has seen a renewed interest, because it is powered by sustainable energy, and can be produced locally.
===Suitable conditions===
A hydraulic ram pump is powered by a body of water flowing downhill with a height difference. A general rule of thumb is that the water can be pumped 30 times as high as the available drive head (the height difference of the water driving the pump). So a head of 1 m can be used to pump up water to ~30m, while a 7 m head can pump water up to 210 m.
===Construction, operations and maintenance===
[[Image:PrincipleHydraulicRam2.png|thumb|right|200px|Components of a hydraulic ram pump:<br>
1. Inlet — drive pipe<br>
Some common operational problems are intrusion of air into the drive pipe, blockage of the intake or valves with debris, knocking due to having too little air in the pressure vessel, freezing in winter and bursting of the delivery pipe if its output is blocked or not pressure relieved.
==Costs== ==Field experiences===
[http://www.ashdenawards.org/winners/aidfoundation This article] describes the impact the introduction of the hydraulic ram has had in the Philippines.
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===Manuals, videos, and links==={|style="font-size: 125115%"
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|{{#ev:vimeo|8454559|200|auto|<center>Pumps - EMAS <br>hydraulic ram, 16min.</center>}}
* [[Solution_of_the_week_12|Akvo solution of the week 12]]
===Acknowledgements===
* This article is adapted from the Wikipedia article [http://en.wikipedia.org/wiki/Hydraulic_ram Hydraulic Ram]
