Abstract: This paper introduces several energy-saving renovation schemes for the combustion air system of the No. 2 reheating furnace in a hot strip mill. It focuses on the frequency converter renovation of the combustion fan and provides a detailed calculation of the economic benefits after the frequency converter renovation. Keywords : Combustion fan, frequency converter, energy saving Keywords : combustion fan, transducer, economy, energy 1. Introduction The design output of the heating furnace at Panzhihua Iron and Steel Group's hot rolling mill is 265 t/h, with a maximum hourly output of 280 t/h. The maximum gas consumption of the heating furnace is 58,500 m³/h·furnace, and the maximum air consumption is 105,250 m³/h·furnace. In actual production, the maximum gas consumption of our plant's heating furnace is 53,000 m³/h·furnace, and the air consumption is around 80,000 m³/h·furnace. In actual production, the typical gas consumption is between 30,000 and 45,000 m³/h·furnace, and the air consumption is between 40,000 and 70,000 m³/h·furnace. [b][align=center]For details, please click: Discussion on Energy-Saving Retrofitting of Combustion Fans for Heating Furnaces[/align][/b]