The Thermal-mechanical Coupling Mechanism Of Continuous Strip Strip Deviation And Bucklingand The Principle Of Early Warning Threshold Setting

Continuous annealing is a very important process step after strip cold rolling.The most common faults in the furnace are mainly strip deviation and buckling.When the strip deviates,the strip moves to the side of the furnace roll,which may cause the contact between the strip and the furnace side,resulting in scratches on the edge of the strip,and even more serious damage to the strip,affecting the production rhythm.At the same time,the strip and the furnace roll are in contact for a long time,and the friction coefficient of the furnace roll is reduced,resulting in slippage,which increases the severity of the strip deviation.When its internal tensile stress is greater than its yield stress,the strip will bend,and twill wrinkles will appear on the surface,which will affect its surface quality,making it difficult to meet customer requirements.When a fault occurs,it is always handled by manual experience,which cannot be solved in time and accurately,which affects the production efficiency.Therefore,this paper establishes an early warning system for strip deviation,slippage and buckling from the mechanism.In this paper,a set of intelligent early warning system for continuous strip deviation and buckling is established from the influence factors such as strip temperature distribution,furnace roll shape,set tension,strip shape,strip speed and so on.(1)A thermo-mechanical coupling model is established for the strip deviation,buckling and slippage of the strip in the continuous withdrawal furnace.For the first time,several typical problems are combined to analyze the cascade relationship between the parameters of the working conditions as a whole.According to the characteristics of thermal-mechanical coupling,reasonable solutions to several problems are given.(2)A typical fault prediction mechanism for continuous failure was established,and the early warning threshold rules for various problems were designed for the first time,and the faults were classified into grades.Based on the early warning mechanism,it can carry out fault early warning and fault classification of strip deviation,buckling and slippage according to the threshold range,and provide feasible solutions for faults.On the basis of ensuring the safety of the production line to the greatest extent,the product level is improved,and when there is a failure trend,the staff is reminded to deal with it in time,so that the on-site failure rate is reduced to below 8%.(3)The mechanism-intelligent prediction system of strip deviation and buckling critical value is developed,and the control accuracy of self-adaptive self-learning is improved by using big data.It has been confirmed by field examples that the use of the forecasting system has achieved accurate forecasting,early warning and intelligent processing of strip deviation and buckling faults,and at the same time visually displayed information such as faults,early warnings and processing.Based on the common problems of deviation,buckling and slippage of industrial production lines,the use of the early warning system can help to judge the occurrence of faults in advance according to the current working conditions,avoid production accidents,and increase the service cycle.Therefore,the development of this system can not only provide solutions to the reasons and methods from the mechanism,avoid urgent medical treatment,and improve on-site production efficiency,but also can intuitively display the statistical information of big data,improve the effect of self-adaptive self-learning,and improve the stability of production.performance and control precision.