QDX small-sized submersible pump (hereinafter referred to as electric pump), consists of three parts: body of pump, seal and motor. The motor is located in the upper part of the electric pump and is a single-phase or three-phase asynchronous motor. The mechanical seal is used between the pump and the motor. The electric pump rotor shaft is made of stainless steel to ensure more reliable mechanical strength of the shaft, which can effectively improve the wear resistance and corrosion resistance of the shaft, and also facilitate the maintenance and disassembly of the impeller. An "O" shaped oil-resistant rubber sealing ring is used for each fixed seal as a static seal.

The electric pump should be able to work continuously under the following operating conditions:

1. The working medium is non-corrosive clean water, the volume ratio of the medium sand content is not more than 0.10%, and the particle size is not more than 0.20 mm.

2. The medium temperature does not exceed 40℃, and the pH of the medium is between 6.5 and 8.5.

3. The electric pump should run within the head range for use.

4. The electric pump should be completely immersed in water, the depth of diving should not exceed 3m, the deepest depth does not exceed 5m, the electric pump is placed more than 0.5m from the bottom of the water, it can not fall into the mud.