The 3/4" and 1" Breurram
A low head/cost 'do- it-yourself' hydraulic ram (Widder, Stossheber, Belier hydraulique) for domestic use. (Supply head: 0.70 - 5.00 m., delivery head up to 35 m.)
The hydraulic ram can pump up the water 10 times the supply head. For instance 0.70 cm supply head means 7 meters delivery head. And 2 meters supply head means 20 meters delivery head.
Working Group on Development Techniques (WOT), University of Twente, The Netherlands.
Why the 3/4" Breurram?
There are many designs of hydraulic rams in circulation. Not only
one can find various factories who produce their own type, also
there are several locally build and constructed hydraulic rams made
by technical advice groups like the WOT. High costs and lots of
work at the installation of commercial hydraulic rams, blocked a
In spite of the fact that ready-made parts have been used, this hydraulic ram appears to reach a very high efficiency for small-scale usage. The design is easily to adjust to the local situation/circumstances.
The comprehension and visibility of the working of the Breurram, makes that no technical expertise is necessary. Even stronger, the Breurram invites you to further experimenting and this way makes a constructive contribution to technical knowledge and the ability to cope.
Conventional Hydraulic rams
The technology of the hydraulic ram has already been used for two centuries. It finds its origin in 1772, when J. Whitehurst in a theoretic way invented the hydraulic ram, using the 'water hammer' (water in movement that abruptly is forced to stop). This idea has been completed by J.M. de Montgolfier. He patented it in 1797. Since then, the hydraulic ram is especially known for her usage as a water pump in developing countries, especially within the framework of drinking-water facilities on a rural level.
Less known is that the hydraulic ram also has its usage and is being used in industrialised countries. Lots of manufacturers set up a production line, many designed their own model. However as a result of this, one is nearly always depending on parts and maintenance of the manufacturers in question. These hydraulic rams distinguish themselves mostly because they are exceptionally robust/solid and because of this, their high costs.
The new design had to meet several requirements. A first necessity is that the parts must be available and durable. These parts should thereupon be simple to assemble (within 10 minutes). The hydraulic ram has to be cheap (+/- 45 Euro). Furthermore the hydraulic ram should be efficient. And as most important but seldom dictated condition, the designer has the clear opinion that the working of the design should be completely transparent and understandable. Too much one looks at the hydraulic ram as a nearly magical machine (scientific curiosity). For a good usage however it is important, that everyone can understand why and how it works. For this reason a do-it-yourself design has been chosen, in which each part can be seen through easily. Within this flexible design you have all the space to adapt the hydraulic ram yourself, making use of the comprehension of the working example. It can also be used as leg up to other, bigger and more difficult to make do-it-yourself hydraulic ram.
For the design the start was made from 10 practical, general principles set up by Prof. J.A. Eytelwein in 1805 (Berlin). The design propositions are for example, that the size of the impulse valve has to be a little bit bigger than the diameter of the drive pipe. Also the volume of the air chamber (to absorb the water hammer) needs to be a bit bigger than the volume of the delivery pipe.
A hydraulic ram is a pump that can be used only in a sloped terrain, because it needs a sufficient fall of water to feed the ram. This source can be any flowing or stagnant water which comes from a certain >= 70 cm height. The water flows through the drive pipe to the hydraulic ram. From this water the largest part is being used for the drive, the rest is being pumped up (raised to a higher level). Water flows (accelerating) through the drive pipe (length = 4-6 times the supply head) into the pump body and escapes through the opened impulse valve. At sufficient speed this valve will close very rapidly, almost instantaneous. As a result of this, a high pressure develops in the ram, by which the water can only escape through the delivery valve into the air chamber, consequently compressing the present air. The water flow stops and moves back towards the drive pipe. The stopping causes an underpressure and as a result of this the delivery valve closes and the impulse valve can open itself. The compressed air in the air chamber retakes its old volume and with this, it is pressing the water into the delivery pipe to its biggest point (delivery head), after which the whole cycle repeats itself.
The air in the air chamber is mixing with the outstreaming water and thus has to be replaced. This can be done by not using tape between the reducing-coupling towards the delivery valve or to drill a 1 mm hole in the reducing-coupling (thus creating a small leakage), so that in the period of underpressure a little bit of air is sucked inside, which subsequently dashes into the air chamber through the delivery valve with the next surge.
Acceleration (+/- 900 millisec.)
Compression (+/- 2 millisec.) / Delivery (+/- 50 millisec.)
Recoil (+/- 50 millisec.)
Because of the small diameter of the ram, the restricted installation requirements and the low costs, this ram is an outstanding example for small-scale usage (domestic use). This can be small irrigation facilities or small drinking water systems for instance for cattle. Because of the high efficiency and the low costs of the Breurram it becomes interesting to link up a parallel connection of several ram pumps - by which each of them have their own drive pipe, but can have a joint delivery pipe - and as a result increasing the capacity of the system. If there is less water available, one or more ram pumps can he disconnected, so the system remains functioning also with a smaller supply of water. Another advantage is, that the system gets less vulnerable to disturbances. If maintenance needs to be done, or if there is a defect at one ram pump, not the whole system will stop functioning.
What do we want to achieve?
The development of the Breurram has not come to an end yet, neither are we pretending to be complete. The most important principle is after all, that people can get to work with this idea and transform it in material and form of their own choice or apply in practice what one has learned. Maybe this could be a stimulation to do future investigations by which one could aim for the use of the ram pump, for instance the drive of other machines.
The start of the ram
The end-part of the air chamber has to be situated lower than the
rest of the ram pump!
In order to pump up lots of water and thus using a lot of water also for the drive (low pump frequency of the impulse valve):
In order to manage as efficient as possible with a small amount of water (high pump frequency especially at low delivery heads):
What to do if the ram doesn't function?
Parts of the 3/4" breurram
The drive-pipe is not specified, this is either a rigid (metal!) pipe or (easier and therefore preferred) tylene tube, also used in drinking water installations. The diameter must be at least as much as the ram, so 3/4 inch. The length is expected to be several meters, from water supply to ram. It should be 4 to 6 times the supply head. All parts should be taped airtight.
NOTE that the drive pipe (water inlet) is not shown above, it should be connected to the open end of the T-joint. A self-wound spring for the impulse valve is shown on the photo, this is necessary when this valve doesn't point upward.
The drive height should be at least half a meter, but the ram cannot pump up high in that case. No more than 5 meters supply is recommended.
If the ram doesn't start when water runs through it or it doesn't seem to be very efficient, the O-ring on the stem of the impulse valve might be changed (taken away or one more added). Another reason can be that the impulse valve doesn't point upward, so you must spring-load it. Otherwise the valve doesn't open itself. Some experimenting is required to get the best operation.
Multiple rams might be connected parallel (each have its own drive pipe and a common delivery, connected at B) and this will increase both delivery and reliability. Also when the amount of input flow decreases (season), some rams can be shut down while still some water is delivered by the others. One big ram will completely stop. Another important factor: maintenance can be done one ram at a time.
WARNING! If the ram is used to pump more than 20 meters high, the thin delivery tube must also be able to withstand this pressure! Be careful when disconnecting the delivery output, because the full pressure is present even when the ram has stopped! Drain the delivery tube or make (add) a pressure release valve that can be opened safely
Videotapes (not free!)
Videotape: De Breurram / The Breurram (Nederlands/English) made by AVT Production Gouda:
Videotape: The Breurram (English)