Research And Application On Mould Level Control System Of Stainless Steel Slab Continuous Casting Machine

Iron and steel industry's rapid development is depending on the continuous casting process control technology development. Mould level control is an important technology index in continuous casting process control technique. Mould level fluctuation of billet is one of the important factors reduce the quality of production. Improving the mould level control precision has important significance to improve the slab quality. Based on the characteristics of stainless steel products, the slab surface quality requirements are relative higher so the mould level control precision is higher than that of ordinary carbon steel. The mould level control system research and design plays an important role in improving the stainless steel slab surface quality by the stainless steel mould level control precision improvement.At present, continuous casting machine mould level control using conventional PID control, the level control in the process nonlinear time-varying interference the level is not stable, general fluctuation is in the range of about±8mm, do not meet the requirements of stainless steel production process easy cause stainless steel slab surface quality. Stainless steel slab defect needs including slab surface grinding. Surface grinding is not only cause the loss of stainless steel, but also to the energy consumption, increase the production cost.First, the existing problem of mold level control system is studied and analyzed. Then combining with advantage of fuzzy and PID control method, a new control method is designed. At last, based on further study of object properties and vortex liquid level detection methods, the designed Fuzzy-PID controller can achieve an online self-tuning PID parameter optimal control. The response speed also becomes fast and overshoot decreased. The stability of whole mould level control system is improved.By the Siemens S7-400 series of PLC, STEP7 programming software and Wincc7.0 configuration software, the control system is realized in the actual production of stainless steel. The result of system stainless steel in the actual production process, mould level fluctuation control in the range of ±5mm, the control precision is far higher than before, operation effect is good. At the same time, system greatly reduces the stainless steel plate slab defect rate, reducing the frequency of secondary treatment and the consumption of electricity and grinding wheel equipment loss, producing certain economic value and, lowering the efficiency of stainless steel played an important role. This thesis research in the application of similar control system to promote.