Submersible water pump motor structure and matched electric appliance

Submersible water pump motor structure and matched electric appliance

1) This submersible water pump primarily consists of impellers, sealing ring, top and bottom guide vanes, two middle sections, water inlet section, water outlet section, pump bearing, top thrust bearing, guide vane cover, middle transition sections and other assembly parts.

2) The impellers, guide vanes and middle section of the pump form the working room. The rotor part includes impellers, bearing housing and steel jacket. The sliding bearings are installed in the water inlet section, water outlet section and the middle transition section to support the rotating rotor parts.

3) To balance the axial force, the impellers are arranged in symmetry. The first stage of impeller rotates in clockwise direction, while the next stage rotates in anti-clockwise direction. The axial forces generated by the impellers when they are working will offset each other. The motor connection thrust bearing will bear the remaining axial force, which improves the service life of the whole pumping unit.

4) The rotor is fixed on submersible water pump coupling and motor bearing frame coupling with seam allowance in radial direction, and with screws in axial direction.

Motor structure

1) The motor consists of stator, rotor, upper guide bearing, lower guide bearing, thrust bearing, base and shaft extension sealing device, etc.

2) The shaft extension sealing of the motor adopts rubber framework oil seal and mechanical seal.

3) A rubber adjustment bladder is installed at the bottom of the motor. When the inside of the motor expands or contracts with the change of temperature, or when the water level outside the motor rises or drops, this bladder can work to balance the pressure of water inside and outside the motor. The motor is equipped with anti-corrosion zinc plate at bottom.

4) The outside surface of the motor case has radiation ribs and water channels for cooling. When the motor runs, it is filled with water inside. The pump wheel below the rotor makes the water inside motor circulate to keep even temperature inside the motor. At the same time, the water stream flowing at high speed outside the motor will take away the heat from motor surface, radiation ribs and water channels.

5) The stator windings of the motor is made of high pressure water-tolerant insulated wire, which has great high temperature resistance and insulation performance. The winding wires are connected with high pressure water-tolerant power cables. On the surface of the ends of windings is fixed a temperature measurer to monitor the water temperature around. This temperature measurer is connected to a four-core cable. Both the two cables reach out from the outlet hole on upper guide bearing base.

6) With cage rotor. The cage uses copper conductor.

7) Bearing bushes are installed inside the upper and lower guide bearing bases. Thrust bearings are installed at the lower part of the rotor. The thrust bearings consist of upper thrust bearing, lower thrust bearing and sliding plate, used to bear axial force. The upper thrust bearing is separated and ring shaped, while the lower thrust bearing is separated and fan shaped.

V. Matched electric appliances

1. Control cabinet

The motor is equipped with special control cabinet for power supply. The motor starts directly under full voltage. The control cabinet is protected against overvoltage, over current and over temperature.

1) Over current protection

This function makes sure no tripping operation happens at any time under rated current.

In case of different degrees of over current, tripping operation will happen within different time periods, as shown below:

When I=1.1 IH, time=0~10 min (adjustable)

When I=6 IH, time=0~8 min (adjustable)

When I=8 IH, time=0~5 min (adjustable)