The Venturi tube, also known as the Venturi tube, is primarily responsible for inducing secondary airflow. When the filter bag is cleaned, when the high-speed airflow passes through the venturi, 5-8 times of the secondary air injected into the compressed air is induced to enter the filter bag, causing the filter bag to rapidly expand instantaneously, and is accumulated due to the reverse action of the airflow. The dust on the filter bag falls off. The venturi tube greatly improves the pulse injection intensity and effect, reduces the amount of compressed air, and saves energy.