A Ram Pump is a kind of water pump that doesn’t need electricity or fuel to pump water to an elevation higher than its source. It is a pure water-powered water pump.
Four makes of ram pump
- Cast steel/iron – these are extremely strong and high efficiency ram pumps that it can last a century but they are expensive or difficult to do at home.
- Welded – these are the most commonly available manufactured ram pump. It is strong but not as strong as the cast ones but they can last more than twenty years. This is also a high efficiency ram pumps like the cast ones. The Gilman Ram Pump is of this make.
- Fitting – this is easily done at home but doesn’t last long because the threads and valves, which are mostly commercial are not design to withstand high pressures. Recommended for low/low lift conditions or for quick set up only – mostly home use.
- Plastic or PVC – plastics don’t last under extreme pressure on High Fall and High Lift condition. It has a low efficiency rating due to its elasticity compared to the metal ones.
1. Operating Principle
The operational principle of hydraulic ram is very simple. It uses the water hammer effect in the ram to transmit water from lower elevation to a much higher elevation. Basically, there only two main sections of a ram pump, the Drive section and the Delivery Section. Each section is has a check valve which controls the flow of water in each section. In the Drive section, there is the Impulse Valve and the Air Chamber Valve for the delivery section. These valves are mechanical check valves which are made to withstand very extreme pressure created by the water hammer effect in the impulse valve when it is slammed close by the force of raging water in the through pipe. The Drive feeds the water from the water source to the ram pump.
2. How It Works
- Water enters from the drive tank to the ram pump through the drive pipe.
Once the water reaches its maximum speed, the Impulse Valve slams close. As it slams shut, the flowing water develops a great deal of pressure in the pump because of its inertia. The pressure forces open the Air Chamber Valve.
- High-pressure water flows through the second valve into the air chamber and compresses the air inside. Compressed air develops and “rebounds” and closes the air chamber valve.
- Excess pressure is relieve at the snifter. Compressed air pushes the water through the delivery pipe.
- The pressure in the pump falls. Air enters the ram pump through the snifter. The Impulse valve opens to allow water to flow and build up momentum again.
- The air chamber valve closes.
- The cycle starts over again
- The ram pump spends so much water. So much water is thrown back to the stream.
- Only a tiny portion of the supply water is delivered.
- Low volume pump.
1. It uses no electricity or fuel, thereby, saving you on high cost of energy.
2. Minimal maintenance as it has only two moving parts, therefore, reducing the “wear and tear” of the machine.
3. Easy to operate
4. 7/24 operation. It operates seven days a week; 24 hours a day.
5. The basic components of Gilman Ram Pump System
- Intake box or spring box – this is a concrete structure constructed to impound and protect water source from getting contaminated or soiled which would affect the quality of water especially if it is used for drinking. There are instances when two or several intake boxes are made in one ram pump location in order to collect more water from different small spring sources. Water sources must be available whole year-round to ensure sustainable operation of the ram. In a low yield spring scenarios, more spring or intake boxes are needed to fill the drive tank with the sufficient flow rate for the ram pump required.
- Drive Tank – it is a small impounding used to hold the water to feed the ram pump. It is positioned where it can feed the ram pump maintaining the drive pipe in a straight line.
- Drive Pipe – it feeds water to the ram pump. It must be rigid to withstand the heavy pressure from the water hammer effect created by the ram pump.
- Ram pump – Ram pumps need the force of falling in order to operate, therefore, it must be located below the water source. Ram pumps cannot operate on wells as there is no fall. The sizes of the ram pumps are determined by the flow rate of water at the source. A small flow water source means small ram pumps, too.
- Delivery pipe – channels the water from the ram pump to the water tank. Polyethylene or PE pipes are recommended for delivery pipes because of its flexibility and strength.
- Water Tank or Storage – This can be ground or elevated tank to store the water from the ram pump.
6. What size of ram pump do you need or how big your ram pump must be?
The Gilman Ram Pumps are designed to fit a wide range of water flow rates. If the water source, such as springs, has a low flow rate, Gilman has a small ram pump for the job. The Gilman Ram Pumps are sized according to the size of the drive pipe. Small drive pipes are appropriate for small water source and so on.
So, in sizing your ram pump, consider two factors. First, it is important to determine the flow rate of water available for the ram pump, and, Second, financial. Large ram pumps are expensive and would entail higher installation costs.
Below is the table of Gilman Ram Pump Models and specifications.
7. How much water can a Ram Pump deliver?
Ram pump outputs vary significantly from one location to the other. Ram pump outputs are determined, primarily, by 3 factors. These are:
1. Water Supply – the more water is fed to the ram, the more water is delivered.
2. Height of Fall or Drive Head
3. Height of Lift or Pump Lift
Ram Pumps do not pump like an electric or fuel-powered pump where the latter produces more water in a given hour than a ram pump. The former delivers so less water than the two but it operates all day long without a single penny is spent for the water power.
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