Basic Research On The Roll Wear Compensation Technology Based On RPECT Principle

As an important production tool in the production of cold-rolled strip,the roll is inevitably worn during the working process,which directly destroys the initial grinding roll shape,thereby affecting the improvement of the quality and accuracy of the strip.At the same time,the high cost of roll production,short service period and frequent roll change caused by roll wear also result in great economic losses.Therefore,the research on roll wear has always been a difficult and hot research topic for related scholars.Roll Profile Electromagnetic Control Technology uses the built-in thermal bulging mechanism of the roll to generate continuous bulging,thereby realizing the micro-scale control of the roll profile.Therefore,it is of great significance to use RPECT technology to implement the full-process online compensation for the wear roll shape caused by the roll wear to improve the control level of the rolling mill and improve the product quality.In order to extract the convective heat transfer coefficient between the cooling liquid and the roll surface under each cooling strategy,a large-scale cold roll in a factory was introduced,and the fluid analysis software Fluent was used to establish its two-dimensional VOF unsteady cooling finite element model,and relying on industrial actual cooling parameters,and analyze the cooling characteristics of the cooling liquid to the roll under each cooling strategy.To provide a basis for the subsequent application of segmented cooling when analyzing the compensation effect of RPECT technology on roll wear based on the two-dimensional Marc electromagnetic-thermal-mechanical model.Based on the principle of "equal heat transfer",this paper uses industrial coolant to cool the rolls in the form of rotation.Equivalent to uniform cooling.In order to realize the application of RPECT technology for roll wear compensation,relying on the large-scale cold rolling work roll introduced in the previous article,an integrated multi-heating zone electromagnetic rod was designed for it,and the electromagnetic-thermal-mechanical coupling finite element model of the roll was established.The roll shape measurement test platform of RPECT roll with external cooling mechanism is used to verify the multi-stage joint control external cooling RPECT roll.To provide a basis for the application of the corresponding control strategy of RPECT technology in roll wear compensation,relying on the previous article to establish a two-dimensional Marc electromagnetic-thermal-mechanical coupling model of large-scale cold rolls,to explore the characteristics of the roll shape curve generated by the combined heating of different heating zones,external The control characteristics of the roll shape curve by heating with different current configuration ratios in the whole area under the cooling mechanism,and the change characteristics of the bulging rate of the large roll with different heating methods are the selection of the heating zone when the electromagnetic control technology is finally used for dynamic compensation of the wear roll shape,respectively.The selection of the current allocation ratio and the determination of the current heating method provide the basis.In order to analyze the application feasibility of RPECT technology in the field of dynamic compensation of worn roll shape,based on the previous research results,a corresponding heating strategy was formulated to realize the full dynamic wear compensation of the in-service roll under the air cooling and external cooling mechanisms,and analyzed the points.The expansion mechanism of the segment cooling technology to the roll shape regulation domain of RPECT technology.