Sealless Pump Motors

Various centrifugal pump designs are available that require no shaft sealing; that is, no packing or mechanical seal. These pumps are completely leakproof, and some are submersible. Such pumps are used when leakage cannot be tolerated or when pumping conditions such as pressure and/or temperature make conventional sealing difficult, if not impossible.

The shaft seal is eliminated by joining the pump and motor housings together to create a single leakproof unit. The impeller and motor rotor are mounted on a single shaft. Most designs permit the pumped liquid to circulate through the motor rotor and motor bearings. However, there are designs where either circulation is also through the stator or the stator is sealed and filled with dialectric oil. See Subsection 2.2.7.2.

Another popular method used for smaller pumps is to separate the pump shaft completely from the motor shaft. A permanent magnet coupling is provided to transmit the motor torque to the pump shaft through a nonmagnetic shell or section of the pump housing. The pump and motor can be integrated in these designs. See Subsection 6.3.2 and 2.2.7.1.

Figure 26 classifies various motor designs and references other places in the handbook where the special features and applications of these units are described in more detail.

FIGURE 26A Pump motors for sealless centrifugal pumps: Submersible pumps
Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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