Automation Reformation Of Top Lance Combustion Control System For RH Furnace Of Qian’an Iron And Steel Co.Ltd.

The top lance system is the main equipment of RH vacuum refining furnace.The integrity of the top lance system directly restricts the normal smelting capacity of RH furnace.In this thesis,the deficiency of the original RH furnace combustion system of the Qiangang company is analyzed,and the effective improvement is made.The research content of this thesis mainly includes the following aspects.This thesis introduces the relevant information of secondary steelmaking and the smelting process of RH vacuum refining and the smelting function of the top lance.This thesis analyzes the hardware structure and working process of the top lance,analyzes the reasons of the high malfunction rate of the ignition system,and puts forward the improvement plan.This thesis puts forward a PLC reformation design for the ignition control system of the top lance.The advantages of PLC system compared with original relay control system are described.The advantages of PLC system compared with original relay control system also has been described.According to the characteristics of PLC,combined with the field control requirements and the status of peripheral equipment,the PLC components were selected and configured.With the design of the peripheral lines,the I/O points of PLC are allocated.The operation process of the equipment is analyzed,the logical flow chart of the operation is combined with the operation of the ladder diagram language,and the control function of the equipment is completed.The fault alarm function of the system is added and perfected,and the fault cause and fault location can be located in time after the problem,which provides a powerful guarantee for the fault treatment.The flow regulation control of the top lance system is changed to the main PLC control to reduce the effect of the field equipment malfunction to the combustion system.Through this reformation,it has been reduced that the malfunction rate of the top lance system and the working intensity of the maintenance worker,and the efficiency of the RH refining furnace is improved.