Hydraulic Ram Tipsheet 50pFind out how this beautifully simple, elegant water pump carriesout its function with great effi...
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Hydraulic Ram Pump Tipsheet - Center for Alternative Technology


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Hydraulic Ram Pump Tipsheet - Center for Alternative Technology

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Hydraulic Ram Pump Tipsheet - Center for Alternative Technology

  1. 1. Hydraulic Ram Tipsheet 50pFind out how this beautifully simple, elegant water pump carriesout its function with great efficiency and a minimum of fuss.Machynlleth, Powys SY20 9AZ / Tel. 01654 705950 / Fax. 01654 702782 / email. info@cat.org.uk / website. www.cat.org.ukThe hydraulic ramThe hydraulic ram, or hydram, isa device which uses the power offlowing water (usually from a springor a stream) to pump a proportion ofthat water to a considerable heightabove the water source. In short, itis a water powered water pump. Asa method of pumping water usedsince the 1800s, the hydraulic ram isundergoing something of a revival forthose seeking a reliable, inexpensiveand environmentally friendly watersupply, or a solution to specific waterrelated problems in less developedcountries.A brief historyIn 1772 John Whitehurst discoveredthe principles of the ram andproduced a machine to raise water tothe upper floors of a building. It wasnot, however, entirely satisfactoryas a small boy had to be employed to open and close a tap.Pierre Montgolfier, one of two brothers to invent the ‘hot air’balloon, developed the first automatic pulse valve in 1798,making the ram a commercial reality. Manufacture in Britainbegan in the early 1800s with the purchase of the originalMontgolfier patterns by the firm Easton & Company. The firmwas purchased in the 1920s by Green & Carter (who had beenmaking rams themselves from the 1870s). The hydraulic rambecame extremely common as a means of pumping drinkingwater supplies and most were installed to serve isolatedrural homes and farms, though occasionally whole villagesdepended on them. The arrival of mains water supplies, orcheap conventional pumps and cheap power to run them, ledto the near demise of the hydraulic ram in the UK. But now,encouraged by the escalating costs of mains water and theunreliability of many private supply systems, hydraulic rams arebecoming an increasingly popular choice of water supply.How it works(See reverse for diagram.) Water is taken from a point upstreamthat is slightly higher than the ram, travels down the drive pipe,through the pulse valve and into the waste drain.As the water flows, its speed increases until the pulse valveis no longer able to pass the volume of water flowing, andthe pulse valve snaps shut. With the outlet closed the flowof water suddenly stops, producing an increase of pressurein the body of the ram – the extent of which depends on theheight and distance from which the water is flowing. The resultof this increase in pressure is that a portion of the water inthe body of the ram is forced upwardsthrough the delivery valve into the airchamber. The water, which is forced intothe air chamber, finds its way througha pipe known as the rising main to theplace where it is required for use, witha continuous flow being maintained solong as the ram remains working. Whenthe pressure passes, the delivery valveshuts, preventing the water from runningback, allowing the pulse valve to openand the cycle to start again. This seriesof events occurs from between 40 to 90times per minute, depending on factorssuch as the size of the hydraulic ram andthe fall of water driving the ram.The fall of water necessary to work aram may be as low as 500mm and, withsuch a fall, water may be raised to 18m.With higher falls water can be raised toupwards of 100m or more in height and5km in distance.Future useAny site that is close to running water, but uphill from thatsupply may well be able to benefit from a hydraulic ram. It canbe used for purposes such as lifting drinking water from springsin valleys to higher settlements, or lifting irrigation water fromstreams or raised channels. Green & Carter’s ‘Compound’ Ramalso allows pure water to be pumped using an impure source.The installation of ram systems is fairly straightforward andcan be carried out by inexperienced or local labour from detailsprovided by the manufacturer. With only two working parts,a commercial hydraulic ram may provide a water supply forover a hundred years without replacement. It needs very littlemaintenance and will continue to pump water as long as thereis water to pump, without emitting pollutants or greenhousegases and without running up your fuel bills.AvailabilityGreen & Carter and AllSpeeds manufacture hydrams in the UK:Green & Carter, Vulcan Works, Ashbrittle, Nr Wellington,• Somerset, TA21 0LQtel: 01823 672365; www.greenandcarter.comBlake Hydram (AllSpeeds Ltd.), Royal Works, Atlas Street,• Clayton Le Moors, Lancashire BB5 5LWtel: 01254 615 100; www.allspeeds.co.uk/blake_hydramMike Williams, Lon Parcwr, Ruthin, Denbighshire LL15 1NJ;• tel: 01824 702229; supplies hydraulic rams and parts andservices and repairs existing rams.Less paper, more trees: download this tipsheet and other titles at www.cat.org.uk/catpubs
  2. 2. Reprintedbykindpermissionof‘TheGuardian’©TheCentreforAlternativeTechnology,2005,updated2006.PublishedbyCATPublications,CATCharityLtd.Registeredcharityno.265239