A submersible pump is a device which has a sealed motor close-coupled to the pump body. The whole assembly is submerged in the fluid to be pumped. The main advantage of this type of pump is that it prevents pump cavitations, a problem associated with a high elevation difference between pump and the fluid surface. Submersible pumps push water to the surface as opposed to jet pumps having to pull water. Submersibles are more efficient than jet pumps.

Submersible pumps are found in many applications. Single stage pumps are used for drainage, sewage pumping, general industrial pumping and slurry pumping. They are also popular with aquarium filters. Multiple stage submersible pumps are typically lowered down a borehole and used for water abstraction or in water wells.

A centrifugal pump is a uses a rotating impeller to increase the pressure of a fluid. Centrifugal pumps are commonly used to move liquids through a piping system. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), from where it exits into the downstream piping system. Centrifugal pumps are used for large discharge through smaller heads.

A centrifugal pump containing two or more impellers is called a multistage centrifugal pump. The impellers may be mounted on the same shaft or on different shafts. If we need higher pressure at the outlet we can connect impellers in series. If we need a higher flow output we can connect impellers in parallel. All energy added to the fluid comes from the power of the electric or other motor force driving the impeller.

A submersible sewage pumps are used to dish out sewage/waste water. Since it is sometimes dangerous to send the people into the sewage or the wet pit, therefore these pumps come handy. These pumps move spherical solids (usually in range 40 mm to 100 mm) with considerable ease. Some sewage chopper pumps are used to handle larger concentrations of solids and/or tougher solids that conventional sewage pumps cannot handle. Chopper pumps are generally used in municipal and industrial wastewater applications and provide clog-free operation by macerating those solids that might clog other types of submersible sewage pumps.