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Industrial production of the hydram is replaced by DIY instruction set using a bag of cement, bits of wood and scrap rubber, still attaining good water lifting performance.

Please visit also our wiki research pages. (D38)

Relevant information and discussion in appropedia.

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Concrete Hydram
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Introduced at users level Hundredfold reduction of cost Applicable within poverty Income Nutricion Rural

Utilization of the principle of the Hydraulic Ram Pump (Hydram) for water lifting. Locally manufacturable at extremely low cost and with maintenance requiring simple tools only. See this video on our Concrete Hydram project in Guatemala.

The Concrete Hydram pumps water up by the energy of water streaming down from a basin. Working automatically, the hydram can lift a little water 15 meters higher for a lot of water streaming down 1 meter. It pumps with an energetic efficiency of up to 50 %.
Reliable functioning is guaranteed if upkeep can be done with tools as available to the user, a farmer most often. This quality is realized by using materials commonly available, such as cement, steel wire from discarded car tires, wood, cloth and bits of wood. For this reason no machined steel parts are used. As the actual method of construction is made easy to learn, either the user/farmer of the local entrepreneur can produce it at very low cost.

Additional information
Video's explaining function and construction of Demotech's Concrete Hydram

  • This computer animation resembles closely the recently build hydram in Guatemala.

  • Experimental constuction of the Concrete Hydram in Palestina, a village in Guatemala

Planned progress
Hydraulic ram pump should be able to pump water from a clean and safe source when available, thus not only from the primary drive water source.

Internal links

Letters about the introduction of Demotech's Hydram in Guatamala

One of Demotech co-workers, Bram de Vries, will mail Demotech regulary about the results and experiences of his work in Guatamala. He will stay there for three month on behalf of his study Antropology at the Utrecht University. His idea is to see how people he will meet will react to the idea of applying the Hydraulic Ram Pump in their environment.

In this paper his mails will added one after the other as soon as they arrive.

External Links

Links related to Hydraulic Ram Pumps

What other people say...

If you like you can add your own comment

by Reinder - Thu Nov 01 (2001)
Cheapest delivery pipe for hydraulic ram pump
Auke, collegues and freinds
Just like to give you a bit of an idea at what level of practical use Demotech's ram pump has arrived
My main concern was about the long pipe leading the water upwards. Because of cost reduction it hardly could be anything else then the thinnest plastic (irrigation) pipe available. One inch diameter seems current in Africa in some places. To guard it against theft, it should be burried under ground. Sometimes it is possibel to guide the water first up hill throught the plastic pipe, then horizontal to the place of use. For that part the traditional bamboo piping can be very usefully applied
- It is not properly researched how to handle the air bubbles that come into the rising delivery pipe. My finding is a lot of pressure is lost in air pockets in the pipeline where it runs downhill for some short length
In this case it helps to have a very thin pipe, to get a water velocity high enough to push the air along. Then it sort of becomes an air bubble water lift pump, at least a hybrid solution. If this helps, the design should develop in the direction of taking in (sniffing) more air. If the airbubbles can not get a helping function, then the rampump should be developed toward using some other solution for absorbing te shock
- In the Demotech design, it was babtisized " Soft Machne", about one bag of cement is needed or less. Material for rubber strips and wooden connectorsis aivalable for free. So the only restriction for the poorest people in using a Soft Machine is the cost of the delivery pipe. Would it be welcome to start a collaboration on tackling that last chackle of the chain? I could ask people of the WOT- research facility in Enschede/ The Netherlands if they can work on this problem
Apart from mailing it to you, I'll put this message to you also on Demotech's website in a forumpage. I would appriciate to receive your answer also through that forumpage
Best regards, Reinder

by hanna - Tue Dec 03 (2002)
hydraulic ram pump
Am extremely interested in this pump and would like to receive more detailed technical info
Also, I would like to get in contact with the people running the keur mousse- project, since I have been doing similar things not far from keur mousse- and have written and prepared a project with the aim of promoting sustainable energy uses for waterwinning and irrigation
this involves quite some ground and experiences in the field, since 1994, are encoureaging, with the ropepump adapted // velo-ropepump- solar rope-pump
please contact me at 06-24861712

by john Homes - Sun Dec 07 (2003)
Hydraulic Ram Pump
Dear Hanna: How are you doing ? With limited money, I'm can't afford to BUY a Hydraulic ram pump. I'm would like to learns how to built one. Could you e-mail the details of building ram pump ? the simple the better. Thanks you. John

by Reinder / Demotech - Sun Nov 02 (2003)
Re: Hydraulic Ram Pump
With limited money, I'm can't afford to BUY an Hydraulic ram pump. I'm would like to learns how to built one. Could you e-mail the details of building ram pump ? the simple the better. Thanks you.
> John John, hello! Your reply to Hanna at the forum page of escaped my (as moderator) attention. I wonder if you still have interest in such a pump at no cost. Then please read the messages recently posted at . Regards, Reinder

by Ray Grove - Sun Nov 02 (2003)
Hydraulic ram water pump
Can you send me any info on how to build a hydraulic ram water pump i am quite good at DIY and would appreciate any plans or where i could get any info

by Reinder / Demotech - Sun Nov 02 (2003)
Re: Hydraulic ram water pump
> Can you send me any info on how to build a hydraulic ram water pump i am
> quite good at DIY and would appreciate any plans or where i could get any
> info Ray, hello! Sorry, no manual availble as yet. You are welcome to come over to this place and get a training how to build them, at the same time we could make that missing manual. In case you are active in the field of development projects, this could be time well spend for you. Demotech's rampump is designed to serve people who's resourses are limited to buying one bag of cement for this purpose. The result is exellent, but of course it takes some special trcks. A manual for a more normal approach was published by ITDG in London. Their rampump is composed out of fitting parts that plumper workshops may have available. Good luck with your achievement! Reinder

by J.C. - Fri Dec 03 (2004)
hyd. rams
having had an interest in the H. ram for many years its difficult to believe that there is not more info on the home built units. This thing has been around for almost (ever). I hope that someone or several people who have usable,working home built pump will provide some answers to those of us who want to build our own units and share the information

by - Sun Dec 05 (2004)
Solar powerd Hydralic Ram Pump
I work on simple way to use the Hydralic Ram Pump without water fall. The energy to drive the hydraulic Ram Pump comes from the heat from the sun
The tecnics is to use a very simple Low temperature water Stirling engine witch take heat from the sun and coold by the pumping water. The stirling engine use water inside instead of a power piston. I have build several prototype. The test prototype is made of very simple components. And the new thing about this type of stirling engine is no need of rubber diaphargm. Instead I use a simple no friction under water line hydraulic piston (made by a lipstic in my first test engine) to drive the displacer. It is very suitble with Water ram pump. I can send some pictures and video cut of the engine.

by - Sun Dec 05 (2004)
ram pump manuals
Hello, The site has some manuals for the ram-pump. This site is typacally for homebuild solutions. is the link to the actual manual.

by ramson hasibuan - Sun Oct 31 (2004)
i'm very interest
shalom i'm ramson from indonesia, and i'm a student of undergraduate in lampung university at mechanical engineering. i'm very interest for hydraulic ram water pump, coz i think it's very usefull for many people in near the river to get water to irrigation. and i need u'r help to give me schematics of hydraulic ram water pump. please............ and include all about hydraulic ram water pump. thank you ramson hasibuan

by Reinder / Demotech - Sun Oct 31 (2004)
Re: i'm very interest
Dear Ramson! For a very long time I have not done further work on the Demotech design for the Hydram. Much of this work was done with students and staff of the Univeristy of Bandung in your country. Last result was that we could make the hydram and the drive made from concrete. It worked very well, was self-starting and looked very promising, It could be made for almost no cost and thus be a real solution for the poorest people. As always more work had to be done on its further development before to be released and published for general use. If you are in a position to assist in this further research, you are welcome. When you study our website, for example the design for the "BathroomBox" you can see how Demotech organizes her research structure
In a similar way Demotech can cooperate with you and your University. However if you just need water and think of using a hydram to pump it up for you, then go to the designs as published by others. For a practical and technical person it is not difficult to weld it together from steel sheet and pipes. Let me know what is of your interest. Regards, Reinder van Tijen, Demotech

by Stuart Luscombe - Mon Nov 01 (2004)
Ram Pumps
I have been trying to get a good Ram Pump for a couple of years can you assit please.I have a water hole about 100 feet deep bigger than a Football oval however it does not flow all year what would you surghest. Kind regards, Stuart

by Reinder / Demotech - Mon Nov 01 (2004)
Re: Ram Pumps
Look at Rope Pump in this website when you need a water pump to be installed in a tube well. If it dries up too easely, then consider to have it dug deeper or at another location.

by - Thu Dec 01 (2005)
do you have plans?

by Reinder / Demotech - Thu Dec 01 (2005)
Re: rampump
> do you have plans? Hello Jeb, Yes, recently plans came up to test our latest design in Guatamala. If you are also in a position to test the hydram, let us know, give us some details and let us cooperate. Reinder

by - Sat Dec 03 (2005)
calculation air chamber ram pump
i have a problem about calculation of air pressure in air chamber and about aproximately volume of air chamber with formula + equations. if you have article or something about my problem please give me solution, with send to my email or because that calculation i use to analysis at Final Report (study case)at my college iin Indonesia

by - Tue Dec 06 (2005)
Please i would like to get details about the manufacture of hydrams.The ability yo raise water cheaply shall hvae a revolutionary approach to agriculture in our eueal areas.Can we send someone to study the proces ? Can you send someone to teach us the process? R.Moki Monono Institute of Rural Development Through the Application of Science and Technology IRDAST Limbe Cameroon

by Reinder / Demotech - Tue Dec 06 (2005)
Hydrams for rural Cameroon
Dear Mr. Moki Monono, This summer at Demotech's lab in the Netherlands we will work on our latest design improvements. In November we will test it in Guatemala. We may be able to come to Cameroon to instruct your organization and others in January 2007. Read my mail, that I have send you on this subject. Kind regards, Reinder van Tijen

by charles - Wed Dec 07 (2005)
I am looking at your site and tried to respond and help some who had questions about building a ram pump but it seems that those who submit a email address must have deleted their account and I get the mail back. SO let me share a address with those who may want to build a pump. I have built several pumps and they work.

by - Wed Dec 06 (2006)
ram pump
i have a farm but the source of water from a creek 20 meters below. im really interested in putting a ram pump for irrigation purposes. please send me detailed plans and design of an indigenous ram pump.thanks

by Reinder van Tijen - Wed Dec 06 (2006)
Help with ram pump
Right now we do a project in Guatemala and review our best practices with the construction of the ram.
If you give us your mail address we can discuss if it may work for both of us to involve you in our present research.
Please mail us about the local conditions, such as available fall in meters and available water flow, that should not be less then 2 liter/second.

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