Efficient low-lift submersible sewage pump

The invention relates to an efficient low-lift submersible sewage pump which comprises a submersible motor, a wire outlet device, a volute casing, a pump cover and an impeller, wherein the pump cover is connected to a lower end cover of the submersible motor by a bolt, a rotor shaft of the submersible motor passes through the pump cover, the impeller is fastened on the rotor shaft by a key, the volute casing is installed on the pump cover, an impeller ring is in sealing connection with a water inlet of the volute casing, and a water pump is coaxially connected with the submersible motor; the flow surface of the pump cover is streamlined; the impeller is of a mixed flow structure, and a back cover plate is arced; the impeller, the pump cover and the volute casing are assembled to form a smooth semi-closed shape which is similar to a streamline; heat-conducting material insulating paint is coated on the outer surface of a stator of the submersible motor, and a cable of the submersible motor extends from the side of the motor. The efficient low-lift submersible sewage pump has the characteristics of large flow, low lift, strong sewage discharge capability and high efficiency and is suitable for sewage treatment, and the requirement of large-flow sewage discharge of the municipal sewage treatment and the like is satisfied.