Coil pump
A coil pump is a low lift pump which is composed of a tube, shaped as a coil and mounted on a rotating axle powered by an engine or an animal capable of turning the axle around rapidly. Due to the rotation, water is then picked up by the tube and pumped upwards in the hose.
Application
The coil pump, as many low lift pumps, is commonly used for irrigation purposes and for drainage of lands. It is currently still used by farmers in Asia.[1]
Advantages
The coil pump was built as an alternative to the Archimedean screw. Unlike the Archimedean screw, it can run horizontally while the Archimedean screw is tilted at about 30°. The coil pump, if fitted with a suitable rotating seal, can deliver water to a greater height, typically 5-10m, above their discharge opening.[2] Despite the emergence of new pumps that operate on other principles, the coil pump remains an important tool as some of it other benefits are that they can be built and repaired easily at a very low cost. This is possible as all the components can be built from local resources as metal; which can be obtained and cast into the desired form easily.
Disadvantages
As mentioned before, the pump only allows the lifting of water over a small height. This makes it unsuitable to water drainage or irrigation over larger height differences or many other pumping applications besides drainage and irrigation.