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Rope pump

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[[Image:Rope_pump_icon.png|right]]
[[Image:RopePumpMozambique.JPG|thumb|right|150px250px|[[Rope pump| Rope pump]] on a borehole, made in a local workshop in Mozambique ]][[Image:Rope_pump_action_diagram.jpg|thumb|right|150px250px|[[Rope pump| Rope pump]], An illustration of the pumping action of a rope pump]][[Image:An illustration of the basic rope-pump design in the west circa 1433.jpg|thumb|right|150px250px|[[Rope pump| Rope Pump]] first illustrated in the west circa 1433 <ref>Weisbaden, Ludwig, ed. et al. Facsimile of De Ingeineis, Liber Primus Leonis, Liber Secundis Draconis, Addenda [online]. Germany: Satz Und Druck, 1984. Available at: http://digital.library.cornell.edu/k/kmoddl/pdf/037_001.pdf [April 2009]</ref>]][[Image:RopePumpvietnam.jpg|thumb|right|150px250px|[[Rope pump| Rope pump]] used for rice paddy irrigation in Vietnam]][[Image:RopePumpZambia.jpg|thumb|right|150px250px|[[Rope pump| Rope pump]] used for irrigation in Zambia]][[Image:Rope_pump.PNG|thumb|right|150px250px|[[Rope pump | Rope pump ]], (Victory model) on a hand-dug of 20 meters deep well, made in a local workshop in northern Ghana ]][[Image:RopePumpBicycle.jpg|thumb|right|150px250px|[[Rope pump| Rope pump]], bicycle model, produced and used in Nicaragua]][[Image:RopePumpMotor.png|thumb|right|150px250px|[[Rope pump| Motorized rope pump]], powered by a diesel motor, used for irrigation. Pumping from a 25m well.]][[Image:Rope pump cross section.jpg|thumb|right|150px250px|[[Rope pump| Rope pump]] Cross section diagram of a rope pump on a capped well]] 
The '''Rope Pump''' is a highly '''efficient''', modern and '''low cost''' pump and one of the few designs that can truly be operated and '''maintained totally at a village level'''. There are various modern developments of the ancient design but the basic design of all pumps is '''a continuous loop of rope with pistons (or plastic washers) attached to it, the rope passes up through a plastic pipe with only a small clearance, thus allowing the pistons to push the water up and out of the top of the pipe'''. Rope pumps have proven highly successful and there are hundreds of thousands of pumps in use world wide and used for anything from community adn domestic water supply to irrigation and cattle watering. For wells down to 35 m, rope pumps are often five times cheaper and more sustainable than standard piston pumps. Rope pumps can be powered by hand, bicycle, motor, horse, or wind power.
==History and social context== ==== Origins ====
The almost intuitive design is known by many other names including the paternoster (after the beaded prayer chain it resembles), liberation or rope-and-washer pump. It is a relatively recent development of the ancient chain-and-washer pump. Evidence of the chain-and-washer pump dates back as far as two thousand years, to feudal China <ref> Fraenkel, Peter, and Thake, Jeremy. ''Water Lifting Devices, A handbook for users and choosers, 3rd ed.'' UK, Rugby: Intermediate Technology Publications Ltd, 2006.</ref>. The earliest report of the design in the west is cited <ref> Olsen, J. P. ''Greek & Roman Mechanical Water-Lifting Devices: The History of a Technology''. Toronto, Canada: University of Toronto Press, 1984. </ref> as that illustrated by the Sienese early renaissance engineer, Tacolla, circa 1433 <ref> Tacolla, Mariano. ''De Ingeineis'', Liber Primus Leonis, Liber Secundis Draconis, Addenda. c. 1433, folio 80. </ref>, a copy of which is given in the figure to the right <ref>Weisbaden, Ludwig, ed. et al. ''Facsimile of De Ingeineis'', Liber Primus Leonis, Liber Secundis Draconis, Addenda [online]. Germany: Satz Und Druck, 1984. Available at: http://digital.library.cornell.edu/k/kmoddl/pdf/037_001.pdf [April 2009]</ref>. In the 1970 and 80s the basic design was developed by numerous individuals, the most prominent of which were Alberts <ref>Alberts, J. H. The rope-pump - an example of technology transfer. ''Waterlines'', January 2004, Vol. 22 (3), 22-25.</ref>, Haemhouts <ref>Sandiford, Peter, et al. The Nicaraguan Rope-pump. ''Waterlines'', January 1993, Vol. 11 (3).</ref> <ref> Lammerink, M.P. et al. ''EVALUATION REPORT NICARAGUAN EXPERIENCES WITH ROPE PUMP'' The Netherlands: IRC, 1995. Available at: http://www.ropepumps.org/English/IRC-1995-Evaluation.pdf</ref> and Lambert <ref>Lambert, R. A. ''How to build a rope-and-washer pump''. London: Intermediate Technology Design Group, 1990.</ref>. and Thorpe. They applied the simple design as a tool aimed at economic and social development. They took advantage of low cost and versatile modern plastics to produce the modern rope-pump design.
 
==== Recent Experience ====
Because of its low cost, the pump is also popular for domestic use. A survey among 5,025 rural families in Nicaragua indicates that a rope pump increases income, even if used for domestic purposes only. Families with a pump earn US$ 220 per year more than families without a pump. In Nicaragua the pumps are now being produced commercially by 20 workshops.
 
Different models of Rope pumps were introduced in Africa. This introduction has not always been successful: in one projects over 80% of the pumps did NOT work after one year! However, with the "right" models and the "right" user training, up to 90% remain in operation in Africa, as the Victory model in Ghana and the Elephant model in Zimbabwe have proved.
==Suitable conditions ==
* Type of well: dug well or borehole
====Manufacturing and Materials====
The rope pump can be produced with locally available standard materials and local skills, such as an artisan workshop.
The frame is welded from mild steel. The handle axle is a mild steel pipe (some design use bearings, either ball bearings or wooden bearings, other employ a steel bushing. The pulley wheel is assembled by fitting the cut-off sides of a tyre on a rim, which generates a nice 'v' shape which provides good traction on the rope. The ropes are made of Polyethylene, Polypropylene, or Polyamide fibres varying from Ø 4 to Ø 8 mm. Natural fibres are not suitable, as they will lengthen when wet, and degrade too fast. The pistons are injection moulded plastic with no seal. The rising main are PVC pipes ranging from 20-50mm diameter (depending on lift). The guide box can be made of concrete with a ceramic insert (some designs use cast in glass bottles), or made of wood with a pvc lining.
 
====Installation====
The installation of the Rope pump is easy and does not need any lifting equipment or special tools. The pumps are generally installed in dug wells but also versions that fit into boreholes are available.
One of the main strengths of the rope pump is that '''all''' maintenance is relatively simple and can '''easily and genuinely be done at village level'''. All spare parts can, like the whole pump, be manufactured in any small town with only the most basic welding machine, other standard hand tools and a basic supply of standard items like PVC pipe, GS pipe and round bar. The most frequent repairs are simple and consist mainly of repairing the rope or handle.
Although easy and simple to maintain it is important the user is instructed in why and how to maintain and repair their pump. Evaluations show that rope pumps on communal wells can be maintained by the users under certain conditions. On pumps shared amongst large groups one of the main conditions is a very high level of community coherence and responsibility. If the rope pump technology is introduced properly, like often is the case with the Zimbabwe Elephant Rope pump, up to 90% of rope pumps remain operational, even after many years.
 
====Efficiency & Theoretical Models====
 
====Motorized rope pumps====
Similar to hand rope pumps, the pump part can be maintained and repaired by the users. The motorised rope pump is being tested in Columbia and Nicaragua.
==CostCosts==
* The Rope Pump costs between US$ 30-150 depending on model, location of production, and cost of materials and labour.
* Cost of introduction: between US$ 10,000-30,000 per project, including 20 pumps, engineering and hands-on training.
* Rural water programme: US$ 150,000-200,000 per project, including 1,000 pumps, start up of production facility and hands-on training.
==Country Field experiences==Because of its low cost, the pump is also popular for domestic use. A survey among 5,025 rural families in Nicaragua indicates that a rope pump increases income, even if used for domestic purposes only. Families with a pump earn US$ 220 per year more than families without a pump. In Nicaragua the pumps are now being produced commercially by 20 workshops.  Different models of Rope pumps were introduced in Africa. This introduction has not always been successful: in one projects over 80% of the pumps did NOT work after one year! However, with the "right" models and the "right" user training, up to 90% remain in operation in Africa, as the Victory model in Ghana and the Elephant model in Zimbabwe have proved. 
In 2008, rope pumps are used in over 30 countries. Below the experiences in Nicaragua, Zimbabwe and Ghana are listed.
A recent interesting development in Burkina Faso has been the re-design of the bottom guide box to include a non-return valve (foot valve) thereby ensuring that water is immediately available from the first turn of the pump handle. This is currently being piloted on a few pumps.
==Reference manuals, videos, and links== ====Manuals====
* [http://www.practicafoundation.nl/wp-content/uploads/PDF/practica-180306-rope-pump-manual-ethiopia-march-2006-complete1.pdf Rope Pump production manual], produced by [http://www.practicafoundation.nl/ PRACTICA] and [http://www.etc-international.org/index.php?id=41ETC ETC Foundation]. It has 86 pages and contains detailed instructions.
* Construction manual [http://www.connectinternational.nl/english/smartmodules/smart-tec/pumps/ropepumpproduction Connect International].
 ==Movies==Videos====
* [http://www.youtube.com/watch?v=-o9jzEcu57A Rope pumps around the world (Connect International, Netherlands, 2008)]
* [http://www.youtube.com/watch?v=06JoZlo77gk Small scale irrigation with a rope pump, Zambia (Connect International, Netherlands, 2008)]
* [http://www.youtube.com/watch?v=dGVvdcl4z8I Rope pump documentary part 2]
 ====External links====
* [http://www.ropepumps.org/ www.ropepumps.org website]
* [http://www.irc.nl/page/31886 Rope pumps: out-perform conventional handpumps on most counts in Ghana test]. Article on IRC.
* [http://www.rwsn.ch/documentation/prcollector.2009-04-05.2482958002/skatdocumentation.2011-07-01.0268979788/file 'Low Cost Handpumps' RWSN Field Note 2011-3]
==ReferencesAcknowledgements==
<references/>
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