3.1. Concept 1
The first concept is a pump that is made up of a cylinder, the water suction, the piston, the piston
rod, check valve, discharge pipe and a handle.
Figure 1: The first concept water pump
The body of the pump contains a valved piston which moves up and down. When the pump is
primed, the piston is raised. As the air cannot pass the piston, a small vacuum is created in the
cylinder, and this reduces the atmospheric pressure on the surface of the water in the suction
pipe. The air and the water in the pipe will follow the piston by moving upwards because the
atmospheric pressure is now greater that the air pressure on the water in the pipe.
At the top of the cylinder the piston stops, and the check valve closes trapping the air in the
cylinder. On the next downstroke, the air that is trapped is compressed between the piston and
the bottom of the cylinder. On the next upstroke, air will be drawn out the pipe and the water will
rise higher, eventually flowing into the cylinder under the piston. With the cylinder and the pipe
full of water, the check valve closes, and this traps water into the cylinder. On the following
downstroke, the piston and the valve pass through water and, when the piston reaches the bottom
of the cylinder, the piston valve closes, and the water is trapped above the piston. On the next
upstroke, the water above the piston is lifted out of the pump through the discharge pipe and at
the same time more water is forced into the cylinder through the check valve.
On each successive downstroke, the piston valve will close, and water will be trapped above the
piston and with each successive downstroke, the water above the piston will be lifted out of the
cylinder. This is how water will be lifted from the ground up until it reaches the top of the
cylinder, and it flows out of the discharge pipe.
Advantages:
1. This manual water pump is easy to install.
2. The parts that are required are easy to find and they do not cost a lot of money.
3. The manual water pump is easy to operate and does not require any source of power to function.
Disadvantages:
1. The pump is easily broken when it is not maintained accordingly.
2. Depending on the length of the pump, it might require a lot of strength to operate.