Design And Implementation On Temperature Control System Of Continuous Annealing Furnace

In the iron and steel metallurgy field, annealing is an indispensable technical process in the steel production and surface finish and also the key procedure before the cold rolling production. Continuous annealing line is a production line in which such technical processes as band steel cleaning, annealing, planishing, phosphorus breaking, recoiling and shearing are completed in regular turn, which facilitates band steel to achieve heat treatment with unbonded defects and good surface quality.TiNi Special Alloy Strips Cold Rolling Plant, completed and put into operation by Special Steel Business Division of Baosteel in the first half of2010, has the annealing line adopted Hot&Cold Continuous Annealing Line or HCCAL for short and choose continuous horizontal annealing technology. The control way of annealing line is PID. As Baogang developing, they need to achieve many A variety of steel strip annealing. But the initial The traditional PID control already can’t suit to variety of strip steel annealing control.This thesis just aims at finding an onsite control way to solve the practical problems based on mathematical model concept.The thesis mainly analyzes the interacts among the temperature control of annealing line, the speed control and cooling of band steel, pointing out that the technology of annealing is so complex that the traditional single circuit, PID control fails to meet the temperature control of band steel. Concerning the control concepts, it explores the current advanced control technology and PID’s theories and methods at home and abroad. Besides that, it also analyzes the strong and weak points between PID control system and model control system, pointing out that mathematical model should be connected with PID control in that PID control has such advantages as simple algorithm, high reliability and small steady residual error while mathematical model has planning in advance and good stability. It designs and realizes the applied control system on mathematical model in annealing line, and it reaches the specific implementation and effectively improves the temperature control instability of band steel in the former annealing line and the like in the control system of Siemens7-400.It has been proved through production that this system is more stable and reliable. For the relevant technical requirements, the system meets the production standards, greatly improve the quality of band steel annealing, and also it reduces the annealing cost and the labor intensity, initially living up to the expected effect.