QDX type submersible motor pump consists of pump, mechanical seal and motor. Pump is at the bottom part of motor pump, which adopt centrifugal impeller. Motor is at the upper part of motor pump and is a single-phase asynchronous motor or three-phase motor. Mechanical seal is between pump and motor, and it is a kind of double end mechanical seal, "O"rings are applied to all static joints of the submersible pump. Inner-installed protector prevents the pump from damages due to abnormal power, clog and overload etc.