Working Group on Development Techniques (WOT)

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.

Features:

  • even applicable in the Netherlands (hardly a difference in height)
  • economically effective (3/4" )
  • efficient
  • durable (long-lasting) material of the shelf parts
  • hardly any parts (simplicity)
  • re-use of the material
  • uniformity of the parts
  • low on weight (2 kg)
  • to construct without drilling, welding and sawing
  • 'do - it yourself - kit' idea (no required insight)
  • to construct within 10 minutes
  • educational (everything is perceptible, by doing it yourself you'll learn the working principles)
  • invites one to further experiments
  • price is approximately 45 Euro
  • one can place the ram without attachment
  • no heavy iron drive pipe but tylene hose/pipe
  • safe
  • an interesting technical shape
  • simply to transform to locally available parts
  • preferably all the parts from one store

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 widely utilisation.
This situation has stimulated Gert M. Breur, after many questions from abroad, to design a new type small hydraulic ram. In this design the most elementary working principles of the hydraulic ram, came back into the picture. Starting from this, such a simple design has been made from the principle 'Less is More', that one could speak of a 'knock up ram'.

Picture of a Breurram

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.

Aims/objectives

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.

Design

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.

Working principle

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.)
Water is streaming via the (drive pipe) into the ram. The water flows out via the open (vertical impulse valve) in order to accelerate. When the velocity is high enough, the valve will close immediately.

Working principle 1

Compression (+/- 2 millisec.) / Delivery (+/- 50 millisec.)
As a result of the rapidly closed impulse valve, a temporarily overpressure (water hammer) is caused which is bigger than the pressure in the air chamber. This causes the horizontal delivery valve to open itself. When the pressure in the air chamber has become higher than the pressure in the pump body, the delivery valve closes again.

Working principle 2

Recoil (+/- 50 millisec.)
The water in the drive pipe will collide with the just closed delivery valve. It will stream back in the direction of the drive pipe. This causes underpressure. The impulse valve can be opened again by its own weight. Via a 1 mm hole, (in the reducing-coupling) in front of the delivery valve, air is sucked into the system. In this way, lost air can be recovered. The little hole is not necessary when contained air is being used in the air chamber, e.g. a inner tube of a bicycle-tire.

Working principle 3

Usage/utilisation

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!
Open and close the ball tap several times at the supply tank - meanwhile paying attention at the almost simultaneous opening and closing of the impulse valve, as long as this valve (at opened ball tap) will start moving by itself - in order to build up enough counterpressure in the delivery pipe.

Adjustment

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):

  • Enlarge the lift of the valve

In order to manage as efficient as possible with a small amount of water (high pump frequency especially at low delivery heads):

  • Reduce the lift of the valve

What to do if the ram doesn't function?

  • Check the valves and the working of the valves. It is advisable to put a strainer/filter before the inflow opening of the drive pipe in order to prevent dirt coming in between the valves.
  • Check if the connections are airtight.
  • Check if there is air in the drive pipe (causing malfunction). That is why the inflow opening of the drive pipe should lay approximately 50 cm below the water level in order to prevent sucking in air.
  • Check if there is enough air present in the air chamber and if the air chamber at the end is laid down sufficiently.
  • Check if the delivery pipe can provide enough counter-pressure (squeeze the delivery pipe, start up the ram, if it is starting now, then the choice of the delivery head was to small). The delivery head should be more than 3 times the supply head!!!!!
  • The impulse valve works, but no water is being pumped up. Probable cause: the delivery valve is defect.
  • The impulse valve stays closed. Cause: the supply head is too high.
  • The impulse valve will not close/stays open. Cause: the supply head is too small or the delivery head is too high.

Parts of the 3/4" breurram

Parts 1
No Parts Amount
1 Sleeve coupling (clamp-connection) 25 x 3/4" male thread 1
2 T-joint, brass, 3/4" female thread 1
3-6 Reducing coupling, brass, 1" x 3/4" male thread 2
4 Foot valve, brass, 1" female thread (ball shape and used in reverse direction) 1
5 O-ring nitrill rubber 6.0 mm x 1.5 mm (to regulate pump frequency) 5
7 Spring-loaded check valve, brass, 1" female thread 1
8-12 Standpipe coupling, 1" x 32 mm 2
9 Pressure tube TRICOFLEX (compressed air vessel) 1 1/4" x 150 cm (more than 10 bar/psi) 1
10-11 Hose (tube) clamp, stainless steel, RVS JUBILEE 30-40 mm 3
13 Quick connect coupling, brass, 1" male thread 1
14 Quick connect hose coupling, brass, 1/2" 1

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.

Parts 2

Exploded view

Exploded-view of ram pump

Exploded-view sideways of ram pump

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

General disclaimer

  1. Het ontwerp van de 3/4 inch ram is eigendom van Gert Breur evenals alle vervolgontwerpen, tenzij dit expliciet wordt vermeldt en dit als zodanig ook bekend is bij de Nederlandse belastingdienst te Zwolle, NL, waar de ontwerpen schriftelijk zijn gedeponeerd.
  2. Het ontwerp is openbaar: iedereen mag het ontwerp gebruiken om de rammen te maken of zelfs om deze te verkopen, op de voorwaarde dat niemand anders iets in de weg wordt gelegd om het ontwerp te gebruiken of te verkopen.
  3. Iedereen mag het ontwerp veranderen of aanpassen, op de voorwaarde dat dit nieuwe ontwerp openbaar wordt gemaakt en dat iedereen dit nieuwe ontwerp mag gebruiken of verkopen, net zoals genoemd in het voorgaande artikel.
  4. Noch de WOT, noch het ROC, noch Gert Breur aanvaarden enige juridische verantwoordelijkheid voor schade of letsel die ontstaat als gevolg van gebreken in het ontwerp de breurram of schade die op andere wijze met het gebruik of functioneren van de breurram samenhangen.
  5. Noch de WOT, noch het ROC, noch Gert Breur aanvaarden enige juridische verantwoordelijkheid voor schade of letsel die ontstaan door het opvolgen van adviezen die door de WOT, door WOTleden, door studenten of docenten van het ROC, door Gert Breur of door iemand anders die in het kader van de mailinglijst rondom de breurram adviezen verstrekt.
  6. De adviezen die de WOT of Gert Breur verstrekken aangaande de breurram, worden ten alle tijde verstrekt op vrijwillige basis, en zijn derhalve op geen enkele wijze opeisbaar.
  7. Op de mailinglijst, op alle informatie over de breurram is het Nederlandse recht van toepassing.

English summary:

  • The design of the 3/4" Breurram belongs to Gert Breur.
  • The design is public domain and has been send to the 'Nederlandse belastingdienst' in Zwolle, NL.
  • You may use, produce or even sell the 3/4" Breurram, on the condition that you do not hinder anybody else to use, produce or sell the ram.
  • Gert Breur nor the WOT, nor any users of the mailing list can't be held responsible for any damage or injure that results from the use of the 3/4" Breurram.
  • All the advices about the Breurram are free and given voluntarily. They can't be claimed.
  • In case of a contradiction, the Dutch "General disclaimer" is more valid than the English summary.
  • All publications on the 3/4" Breurram are subject to Dutch law.

Videotapes (not free!)

Videotape: De Breurram / The Breurram (Nederlands/English) made by AVT Production Gouda:

  • Breukhoven, Essebaan 50, 2900 AV, Capelle a/d IJsel, The Netherlands
  • Tel.: +31 10 4584222

Videotape: The Breurram (English)

  • Apex, PO box 455, 7400 AL, Deventer, The Netherlands
  • Tel.: +31 570 624 960 / fax: +31 570 609 057

Contact address:

A shadow of fertility
  • Working Group on Development Techniques (WOT)
    University of Twente
    PO-box 217
    7500 AE Enschede
    The Netherlands

    postbank account: 2733683

    Tel.: +31 53 489 2845
    Fax: +31 53 489 2671

    http://www.wot.utwente.nl/ (homepage of the WOT)