About hydraulic ram pumps
A hydraulic ram, often known as a hydram, is a hydro-powered cyclical water pump. It takes in water with a certain “hydraulic head” (pressure) and a certain flow rate and produces water with a higher hydraulic head and a lower flow rate.
The gadget employs the water hammer effect to create a pressure that permits part of the incoming water used to power the pump to be elevated above where it began. These pumps are widely available and you can get one from any ram dealer in your area.
Hydraulic Ram Pump Operation
Hydraulic ram pumps use the pressure created by a “water hammer” shock wave to operate. Inertial force exists in any moving object. Energy is required to start and halt the motion of the object, with more energy being required if the motion is initiated or stopped rapidly.
The inertia (or momentum) of a water flow in a conduit resists rapid changes in velocity. Slowly closing a valve allows inertia to dissipate over time, resulting in a small increase in pipe pressure.
When a valve is closed quickly, the flowing water stops, creating a pressure surge or shock wave that travels back up the pipe — similar to a railway stop, where individual train cars smash the coupling in front of them in rapid succession as the brakes are applied.
The larger the shock wave produced, the faster the valve is closed. Because more inertia or momentum is involved, a quicker water flow will produce a greater shock wave when a valve is closed. For the same reason, a longer pipe will produce a greater shock wave.
How a hydraulic ram pump operates:
Water flows from the supply reservoir into the valve box via the driving line. The waste valve is initially open, allowing water to flow through it and into the stream. The waste valve closes quickly as the water flow increases. Water hammer occurs when the waste valve is closed, causing excessive pressure within the pump. This diverts the water past the delivery valve and into the storage tank or trough via the supply line. The water flow within the valve box drops dramatically, allowing the waste valve to open and restart the cycle.
Ram pumps have two key working characteristics: a large amount of water goes out the waste valve, and the pumping motion is cyclic and noisy.
A 2-inch ram pump can deliver 3000 gallons per day (2 gallons per minute) to a storage tank 75 feet above the pump through a 50-foot drive line with a 2-inch diameter steel supply reservoir. At least 31.5 gallons per minute of stream flow is needed for this (assuming a pump efficiency of 50 percent). Using the same length of 4-inch diameter steel drive line, a 4-inch ram pump can deliver the same amount of water to a storage tank that is 245 feet higher than the pump. A minimum of 102 gallons per minute of stream flow is necessary for this.
