Abstract : Based on the heating process requirements, an electrical control system composed of frequency converters, controllers, Eurotherm, and sensors is used to automatically control the air supply to the regenerative walking beam furnace to ensure constant furnace pressure and temperature. Keywords : Regenerative walking beam furnace, furnace pressure, furnace temperature, frequency conversion speed regulation, automatic control 1 Introduction Regenerative high-temperature air combustion technology, as a high-efficiency and low-pollution combustion technology, is the development direction of energy conservation in the 21st century. This technology maximizes the "ultimate recovery" of flue gas, and has the advantages of low energy consumption and energy saving and environmental protection. In practical applications, this technology has strict requirements for its air supply system. Reasonable selection of the control method of the air supply system is an important foundation for ensuring the effectiveness of this technology. 2 Blower air pressure control technology requirements The heating furnace in the No. 1 rolling mill workshop adopts regenerative burners, and the fuel is natural gas. It is divided into three sections: preheating section, heating section, and soaking section. Two blowers are connected in parallel to supply air to the three sections (motor: Y200L1-230kw). The heating furnace was renovated in 2002. However, it was found that its air supply system was inadequate for the plant's needs for heating multiple varieties of steel billets in small batches. Therefore, it was decided to renovate the air supply system. 2.1 Problems with the Existing Air Supply System The original air supply system consisted of two fans with constant motor speeds. The air volume was controlled by air valves installed on the main air duct. Adjusting the combustion atmosphere in the heating furnace required manual adjustment of the air valve opening angle by the operator to change the air supply and thus regulate the combustion atmosphere. The accuracy of the air valve opening was poor, relying heavily on the operator's experience and intuition. Because the air supply exceeded the required combustion air volume, the air valves could not fully open, resulting in increased duct resistance, increased motor load, energy waste, and excessive fan noise. After adopting regenerative burners in the heating furnace, the air resistance of the entire system increases due to the effect of the regenerative balls. The air supply from the original two fans can no longer meet the combustion needs of the heating furnace. Insufficient airflow in the furnace leads to incomplete fuel combustion and an inability to maintain constant temperature and pressure, making furnace atmosphere regulation difficult. This severely restricts the furnace's heating capacity and significantly harms product quality and output. 2.2 Modification Plan The original centralized air supply will be changed to two independent air supply sections: the original two fans will supply air to the soaking and heating sections, and a new fan will supply air to the preheating section. The fans will be controlled by frequency converters. [b][align=center]For details, please click: Application of Frequency Converters in Fans of Regenerative Walking Beam Furnaces[/align][/b]