AIDFI Ram Pump

Ram pumps use the power available in flowing water at an elevation of a few meters to lift a small percentage of that water through a much greater height, to where it is needed. These pumps utilize gravity to collect water from stream sources into the pump’s reservoir, creating a high pressure within the reservoir. The pressure opens a valve, creating pressure now against the air in the delivery pipe, which forces water out through the delivery piped system. AIDFI makes 10 different sizes of pumps with intake rates ranging from 10 to 2500 litres per minute. An average installation serves 50 households or 300 people.

The most novel feature of the AIDFI ram pump is the use of a door hinge for the waste valve, which creates a steel-to-steel seal. This avoids the use of a gasket, which would quickly wear out in this high-impact valve. A further feature is a submersible box around the outflow of the waste valve, which prevents air entering the pump at the end of each cycle. This is important as if air enters the ram body it reduces the efficiency of the pump. The design developed by AIDFI uses mild steel for the body of the ram pump itself, including the final section of the drive pipe and air reservoir. Some critical parts are made from stainless steel to ensure they last throughout the expected lifetime of over 20 years.

For small schemes, an individual pump is used, but for larger schemes, multiple pumps can be connected in parallel or in series (depending on the head and flow rate). The pumps can operate continuously and deliver water to a reservoir.

According to AIDFI, poor maintenance will result in failure of the ram pump. Technical support is provided by local individuals, who have been trained in maintenance and routine replacements necessary for the pump. Payment for service is provided via a community-managed fund. The community using the ram pump may collect a small fee monthly from each household to pay the technicians for maintenance of the system.^{Interview with representative} 

Expected lifetime of over 20 years. ^{Interview with representative}

Testing performed by the manufacturer determined that the product can pump up to elevations of 240 m.

Users must take appropriate precautions when maintaining the hydraulic ram pump.