1. Dry type submersible electric pump:
In the motor shaft extension end by mechanical seal or cushion sealing device, tight seal, to prevent the water immersion motor cavity, keep the machine dry. But due to the limitation of the sealing structure, the depth of immersion in the water can not be too large.
In addition, there is the so-called semi dry submersible electric pump, that is, the motor stator, rotor with a shield between the cover, the stator seal up, so that the separation of water and water, and the rotor running in the water. Due to the existence of the shielding cover, the air gap increases and the electrical performance of the motor is reduced.
2. Oil filled submersible electric pump:
In the motor cavity is filled with insulating oil, to prevent water and moisture dip damage the motor windings and insulation, cooling and lubrication. The insulating oil of the motor can be pressed, and can be pressed. In order to prevent the leakage of oil and water immersion, the shaft extension end still need to use the sealing device. When the seal fails, it will cause water pollution, it is not suitable for the extraction of water for life. In addition, the motor rotor rotates in oil, the resistance is bigger, the motor efficiency is low.
3. Wet submersible electric pump:
Motor stator winding using waterproof insulated wire. The motor is filled with pure water, the rotor immersed in water running, good heat dissipation. Shaft end seal is mainly used for sand sealing requirements before the two submersible pump high. So the structure is simple, easy to manufacture and maintenance. However, the requirements of the pump on the material is high, the parts of the corrosion protection requirements are more stringent.
