There is a strong magnetic magnet inside the hammer head of the air hammer. Before moving, the magnetic hammer head is close to the magnetic substrate. When the three-way solenoid valve is energized and the intake pressure is greater than the fitting magnetic force, the magnetic hammer is detached from the substrate at a high speed and impacted to the bottom. After the impact, the three-way solenoid valve is powered off, the gas in the product is removed, and the hammer is returned to the initial position with the help of the spring. The impact of the air hammer is transferred to the wall of the pipe or barrel, so that the material can flow smoothly.