Research Of Control System For Regenerative Gas Heating Forging Furnace

Regenerative gas heating forging furnace is widely used in steel rolling production as the main production equipment. But control system of traditional heating forging furnace use manual control, considering worker’s skilled extent and seriousness. And it can’t ensure rapid response of the entire system, and it influence the accuracy and stability of control. The fuel mostly use pulverized coal, NOX can easily pollute the environment which produced by combustion. Therefore, it research control system of regenerative gas heating forging furnace against these issues in this paper. It use the way of combination which Japanese OMRON’s PLC of CP1 E series and HMI of WEINVIEW to achieve automatic, and it use gas as a furnace fuel, not only to save energy and to reduce pollution.Based on regenerative high temperature air combustion technology, it introduced the basic principles of regenerative gas heating furnace forging. It designed the overall structure of the control system and regenerative gas heating forging furnace and regenerator. And sensor, transducer, proportional solenoid valves and other components can be selected.To study control strategy of regenerative gas heating forging furnace which including commutation control, combustion control and air-fuel ratio control of system optimization. Against the concept for the commutation control and it is divided into two parts: manual and automatic commutation. Through analyze factor with the influence of commutation time, to establish a mathematical model between commutation time and the heat recovery efficiency, and it determine the best commutation time.Against method of combustion control, to analyze pulse combustion that is suitable for heating forging furnace. This paper introduced the basic principles of pulse combustion and the pulse ignition process. To design combustion control timing of the entire regenerative gas heating forging furnace, and can be more effective controlled temperature of the furnace.Against the concept of air-fuel ratio, to analyze combustion mechanism of regenerative gas heating forging furnace. To design the two methods for the best air-fuel ratio: based on air-fuel ratio analysis of gas calorific value and flue gas oxygen content and based on air-fuel ratio analysis of to search superior extreme value, and the optimal air-fuel ratio can be determined through experimental verification.To select PLC of regenerative gas heating forging furnace control system. Input and output points are allocated. And it designed the main circuit of electrical control system. It designed inverter, pressure sensors, oxygen content sensor and hardware circuit of analog input and output modules, and hardware circuit of temperature controller communicate with PLC. To complete the design of PLC control system software, including start and stop and speed control of the blower and the draft fan, start and stop of air compressor, lifting of the door, purge control, small fire control, fire control, temperature control and communication protocol of PLC and temperature.To complete design of regenerative gas heating forging furnace machine interface. It use with the touch screen of WEINVIEW, to achieve the communication between touch screen and PLC. Human-machine interface achieve parameter settings, temperature display, real-time communications and other functions. And it include the main design of interface, design of operation interface, design of parameter setting interface, design of debug interface and design of help interface.Research on the topic has been applied for regenerative gas heating forging furnace in a machinery factory, and the above theory is applied to regenerative gas heating furnace forging for field-proven. The experiments show that operation is simple about control system with high control accuracy and it can save energy and reduce pollution.