Sewage pump is a kind of centrifugal impurity pump, which is mainly used to transport urban sewage, feces and liquid media containing solid particles such as fibers and paper scraps. The temperature of the transported media is usually not more than 80℃. Its forms are various, and commonly used are diving type (such as QW type) and dry type (such as W type horizontal type and WL type vertical type).Because the conveying medium contains fibers that are easy to be wound or bunched, the pump flow passage is easy to be blocked, which may cause the equipment to fail to work normally or even burn the motor, which may affect the pollution discharge and environmental protection. Therefore, the anti-blocking performance and reliability are important indicators to measure the performance of sewage pumps.This kind of pump has obvious characteristics: it adopts advanced technology, has strong sewage discharge ability and no blockage, and can effectively pass solid particles with a diameter of φ30-φ80 mm; Equipped with tearing mechanism, it can tear and cut off the fiber material and then discharge it smoothly, without additional filter screen; Reasonable design, low power of supporting motor and remarkable energy saving effect; Adopt new material mechanical seal, which can run safely for more than 8000 hours; Compact structure, easy to move and install, can reduce the project cost and does not need to build a pump house; Can be used in the range of full lift to ensure that the motor is not overloaded; The float switch can automatically control the start and stop of the pump according to the change of water level, without special care; The double guide rail automatic installation system is very convenient for installation and maintenance, and there is no need for personnel to enter or leave the sewage pit; Equipped with full-automatic protection control box, it can effectively protect against electric leakage, water leakage and overload, and improve safety and reliability.At the same time, the sewage pump has multiple advantages: compact structure, small floor space, and can be directly installed in the sewage pool because of submerged work, saving land and infrastructure costs; Convenient installation and maintenance, small pumps can be freely placed, and large pumps are equipped with automatic coupling devices to realize automatic installation; Long continuous operation time, because the pump and motor are coaxial, the shaft is short, the rotating parts are light, the radial load of the bearing is small, and the service life is far longer than that of the general pump; Low vibration noise, low motor temperature rise and no pollution to the environment.