Trace rust will not affect the normal operation of the fan, but will affect the dynamic balance of the fan, increase vibration, affect the intake efficiency. Remove rust with phosphoric or hydrochloric acid. Hydrochloric acid phosphate is not only cheap, but also good rust removal. The fan impeller immersed in phosphoric acid, the iron oxide into iron phosphate, into black coating, standing at night, air drying.

When the air is dry, scrape off the iron phosphate. Use vinegar to remove rust. Although vinegar is effective, it is also mild, so the fan impeller should be soaked for as long as possible. Remove from the vinegar and scrape off the rust. Use baking soda to remove rust. Add water to baking soda, slightly thicker than toothpaste. After mixing, it is denuded with friction material.

Use an electric grinder or sander. It is recommended to grind the rust layer from the large grinder, so as to wash the rust layer of the impeller of the tunnel fan, and avoid unnecessary wear and easy to damage the rust layer. After rust removal by the above methods, anti-rust treatment should be carried out on the impeller of the tunnel fan in time, such as painting, plastic spraying or chrome plating, so as to avoid secondary corrosion, but the thickness of the impeller becomes thinner after repeated rust removal. If it is too thin, it is recommended to replace the impeller to avoid other accidents.