Submersible motor pump
Submersible motor pumps are pumps driven by an asynchronous motor. Their hydraulic components (pump casing, impeller, diffuser element) and motor are flooded by the fluid handled.
Submersible motor pumps are installed by being lowered into the pump sump along a guide wire or guide rail arrangement. The pump claw with a rubber profile seal inserted attaches itself almost leakage-free to the piping permanently installed in the pump sump, so that the pump set can be fully flooded. The motor heat is dissipated via the motor housing to the fluid surrounding it.
Submersible motor pumps with liquid-filled motors (e.g. submersible motors) are suitable for operation at any installation depth. Submersible motor pumps can also have air-filled (or less frequently oil-filled) submersible motors which are designed for low to medium installation depths (of up to 80 m). In certain cases, these motors only need to be occasionally or partly submerged in the fluid handled as the motor heat is dissipated to the fluid handled by means of heat conduction and to the atmosphere via the large surfaces of the motor housing by convection or forced air flows.
Applications of vertically installed submersible motor pumps
See Fig. 1 Submersible motor pump
- Fighting floods
- Transporting waste water (See Figs. 2, 3, 5 Waste water pump)
- Drainage (See Fig. 2 Drainage pump and Fig. 2 Pump for use in low-lift pumping stations)
- Irrigation (See Fig. 1 Irrigation pump)
- Cooling (See Fig. 5 Cooling water pump)
- Water disposal (See Waste water lifting unit)
Submersible motor pumps are usually designed as single-stage pumps. They generally do not require a suction line, as the fluid to be handled approaches the pump from all sides. Smaller pump sets are transportable and usually fitted with a level-controlled switch starting and stopping the pump set automatically.
The materials of submersible motor pumps have to be specifically selected for the fluid to be handled and the sand or contaminants it may contain. The pumps can also be designed with explosion protection.
