Submersible pump

A submersible pump is a pump which has a hermetically sealed[?] motor close-coupled to the pump body. The whole assembly is submerged in the fluid to be pumped. The advantage of this type of pump is that, in a large installation, there is a significant reduction in the amount of concrete required to build the reservoir since a separate dry-well is not required.

A system of mechanical seals is used to prevent the fluid being pumped entering the motor and causing a short circuit. The pump can either be connected to a flexible hose or lowered down guide rails or wires so that the pump sits on a "ducks foot" coupling, thereby connecting it to the delivery pipework.

Submersible pumps are found in many applications, single stage pumps are used for drainage, sewage pumping, general industrial pumping and slurry pumping. Multiple stage submersible pumps are typically lowered down a borehole and used for water abstraction.