Abstract : This paper introduces a new method for the integrated operation system of steelmaking material feeding and unloading, and the implementation method and control principle of PLC technology in the new process. Practice shows that the system is reliable and highly automated. Keywords : PLC control, frequency converter, PROFIBUS network. With the rapid development of the iron and steel metallurgical industry, production organization is becoming increasingly rigorous and the pace is accelerating. However, in the feeding system of steelmaking production, some enterprises still use single-bucket feeding, which is inefficient, slow, and has a high failure rate, becoming a bottleneck affecting production. Moreover, during the unloading process, operators are required to operate on-site, and the harsh environment creates many safety hazards for workers. Therefore, how to improve the efficiency of feeding and unloading in the steelmaking production process is an urgent task for these enterprises. 1 Basic Design Idea of ​​Integrated Feeding and Unloading System The new method of integrated feeding and unloading system aims to minimize human factors in the process, shorten the supply time of raw materials for steelmaking production, and at the same time improve the safety factor of equipment operation. In the past, each of the feeding hopper and unloading trolley in enterprises was operated by one person. Because they were far apart, coordination relied on telephone communication, which was inconvenient and sometimes resulted in malfunctions. This new operating system connects the feeding hopper and unloading trolley via a network, allowing one person to operate them, saving manpower and improving efficiency. The design concept of the integrated feeding and unloading system is: replacing single-hopper feeding with belt conveyor feeding; the control room is located at the ground-level belt conveyor; both the feeding and unloading systems are controlled by PLCs, and because they are far apart, a PROFIBUS network is used to connect them, with a WINCC screen displaying the operating status to improve the system's automation level. [b][align=center]For more details, please click: Application of PLC Control in Steelmaking Feeding and Unloading Systems[/align][/b]