Design And Application Of Vertical Annealing Furnace Control System For Hot Galvanized

With the continuous recovery of the national iron and steel market in recent years,industrial technology is also developing rapidly.Various industries have also shown that the demand for galvanized sheet is increasing,and the requirements for product surface are also very high which promotes the improvement of the technology and equipment level of hot dip galvanized steel production line.The vertical annealing furnace is the most important equipment in the hot dip galvanizing line.The role of the annealing furnace has two main roles: one is to restore the plasticity of the strip,removing the previous process due to hardening caused by cold processing,improving the internal performance of the strip to provide performance guarantee for the subsequent production and processing;the second is the final heat treatment of the product,controlling product performance,resulting in different hot galvanized products.In the production process,through a series of heat treatment,the internal atoms with the strip steel reorganized and then changed the internal structure,and the strip surface is reduced to a porous hydrogen,which is conducive to galvanizing.The annealing process has a crucial influence on the output of the galvanized product and the performance of the galvanized sheet.This subject is based on the design work of a company's galvanizing vertical annealing furnace control system to adopt the SIEMENS PLC control system to perform assemble-disperse control of the annealing furnace,so as to achieve the purpose of stable and safe operation of the vertical annealing furnace.This paper takes the design and commissioning of the control system of a company's hot galvanizing vertical annealing furnace project as the background,designing based on the PLC control system design,the heating control mode,and the pressure atmosphere balance control in the furnace according to the requirements of the galvanized product.And the safe factors of the annealing furnace are added to the control system design of the entire annealing furnace to form some self-developed technologies.In addition,this paper analyzes the process requirements and operating characteristics of the annealing furnace.The control system uses a set of SIEMENS S7-400 series for real-time detection and control.The PLC program uses CFC language for editing,and the control program and field technology form PID control through profibus communication and ET-200 m..The on-site monitoring screen is developed and designed using HMI screens in the WinCC environment.After the design of the company's hot galvanizing vertical annealing furnace,the core technology and equipment of the continuous hot galvanizing annealing furnace will be applied to the galvanizing unit.The PLC program and the HMI screen can achieve real-time monitoring and control of the annealing furnace operation.After being put into production,the annealing furnace runs smoothly and can achieve the desired effect of design.It has made outstanding contributions to the innovation and high efficiency of galvanized products.