The invention discloses a self-priming device for a
centrifugal pump, comprising a self-priming device and a
centrifugal pump. The self-priming device comprises an inlet section, an outlet section, a water return
pipe and a
nozzle. The inlet section is in an S-tube shape, the upper end of the inlet section is connected to a water inlet pipeline, and the lower end is connected to the inlet of the
centrifugal pump. A
nozzle is arranged inside the inlet section, and the outlet of the
nozzle points to the inlet of the centrifugal pump. An interface for connecting to the water return
pipe is arranged outside the inlet section. The outlet section is in a
straight tube shape, and the outlet section is located above the centrifugal pump, the upper end of the outlet section is connected to the water outlet pipeline, and the lower end is connected to the outlet of the centrifugal pump. An interface for connecting to the water return
pipe is arranged outside the outlet section, and the inlet section and the outlet section are connected through the water return pipe. The invention enables an ordinary centrifugal pump to have a self-priming function by adding a self-priming device to the ordinary centrifugal pump. The pump only needs to be primed before the first start-up, and the pump is easy to install and can be used immediately after being turned on. After normal operation, the
reflux valve is closed. Since the main pump is a centrifugal pump, the operation efficiency is high, the structure is simple, the
processing is easy, and the use is convenient.