A Based on the jet flow principle, the AELC Type self-suction device is the latest product developed in reference to the advanced technologies of other countries. The AELC Type self-suction device realizes the suction via the jet of gas. This device features in compact structure, light weight and easy operation. It can be directly installed on the pump frame and connected to the suction hole of the pump, so that the pump without self-suction device can perform self-suction. The self-suction can ensure automatic start of the pump when the pump is filled with water. The self-suction device is automatically closed after the pump is started. It is particularly suitable to the marine centrifugal pump.