Using three-dimensional rigid-plastic finite element method base on Lagrange multiplier to analyze the deformation of strip,influence function method to calculate the elastic deflection of rolls and three-dimensionale...Using three-dimensional rigid-plastic finite element method base on Lagrange multiplier to analyze the deformation of strip,influence function method to calculate the elastic deflection of rolls and three-dimensionalelastic FEM to analyze the flattening deformation between work roll and strip,a coupled model was established with a iteration way.The effect of various kinds flatness control method such as bending force,rolls shift and cross angle and also various kind of influence factors such as friction coefficient,strip crown,rolls wear and thermo-crown on strip flatness can be analyzed using this coupled model.A great deal of information for example outlet crown of the strip,front and back tension,rolling force distribution for per length,rolls elastic deformation and forward slip can be obtained.In order to improve computational efficiency,the average change of rolling force for per unit length was added into the criterion to determine if the coupled process is end,which can save 30 percent computing time for one pass but the changes of strip thickness is not large than 5μm.The exploration has certain conductive significance for improving efficiency of other type of mill.展开更多
In order to analyze the hot tandem roiling force, a new logarithmic velocity field is proposed. Using the field and linear EA （equal area） yield criterion, the plastic deformation power for plate rolling is analyzed...In order to analyze the hot tandem roiling force, a new logarithmic velocity field is proposed. Using the field and linear EA （equal area） yield criterion, the plastic deformation power for plate rolling is analyzed, and the friction power is obtained based on the co-line vector inner product method. Then analytical solution of plate rolling power functional is obtained. Finally, by minimizing the power functional, the rolling torce and torque are received. Compared with those measured ones in hot tandem rolling on-line, the calculated rolling forces are in good agreement with the actual measured ones since the maximum error is less than 12~. Moreover, the effects of various rolling conditions such as thickness reduction, friction factor and shape factor, upon separating force, location of neutral an- gle, and stress state coefficient are discussed systematically.展开更多
To solve the coupling relationship between the strip automatic gauge control and the looper control in traditional control strategy of tandem hot rolling,a distributed model predictive control(DMPC)strategy for the ta...To solve the coupling relationship between the strip automatic gauge control and the looper control in traditional control strategy of tandem hot rolling,a distributed model predictive control(DMPC)strategy for the tandem hot rolling was explored,and a series of simulation experiments were carried out.Firstly,based on the state space analysis method,the multivariable dynamic transition process of hot strip rolling was studied,and the state space model of a gauge-looper integrated system in tandem hot rolling was established.Secondly,DMPC strategy based on neighborhood optimization was proposed,which fully considered the coupling relationship in this integrated system.Finally,a series of experiments simulating disturbances and emergency situations were completed with actual rolling data.The experimental results showed that the proposed DMPC control strategy had better performance compared with the traditional proportional-integral control and centralized model predictive control,which is applicable for the gauge-looper integrated system.展开更多
文摘Using three-dimensional rigid-plastic finite element method base on Lagrange multiplier to analyze the deformation of strip,influence function method to calculate the elastic deflection of rolls and three-dimensionalelastic FEM to analyze the flattening deformation between work roll and strip,a coupled model was established with a iteration way.The effect of various kinds flatness control method such as bending force,rolls shift and cross angle and also various kind of influence factors such as friction coefficient,strip crown,rolls wear and thermo-crown on strip flatness can be analyzed using this coupled model.A great deal of information for example outlet crown of the strip,front and back tension,rolling force distribution for per length,rolls elastic deformation and forward slip can be obtained.In order to improve computational efficiency,the average change of rolling force for per unit length was added into the criterion to determine if the coupled process is end,which can save 30 percent computing time for one pass but the changes of strip thickness is not large than 5μm.The exploration has certain conductive significance for improving efficiency of other type of mill.
基金Sponsored by National Natural Science Foundation of China(51074052,50734002)
文摘In order to analyze the hot tandem roiling force, a new logarithmic velocity field is proposed. Using the field and linear EA （equal area） yield criterion, the plastic deformation power for plate rolling is analyzed, and the friction power is obtained based on the co-line vector inner product method. Then analytical solution of plate rolling power functional is obtained. Finally, by minimizing the power functional, the rolling torce and torque are received. Compared with those measured ones in hot tandem rolling on-line, the calculated rolling forces are in good agreement with the actual measured ones since the maximum error is less than 12~. Moreover, the effects of various rolling conditions such as thickness reduction, friction factor and shape factor, upon separating force, location of neutral an- gle, and stress state coefficient are discussed systematically.
基金This work was supported by the National Key R&D Program of China(Grant Nos.2018YFB1308700)the National Natural Science Foundation of China(Grant Nos.U21A20117 and 52074085+1 种基金the Fundamental Research Funds for the Central Univer-sities(Grant No.N2004010)the Liaoning Revitalization Talents651 Program(XLYC1907065).
文摘To solve the coupling relationship between the strip automatic gauge control and the looper control in traditional control strategy of tandem hot rolling,a distributed model predictive control(DMPC)strategy for the tandem hot rolling was explored,and a series of simulation experiments were carried out.Firstly,based on the state space analysis method,the multivariable dynamic transition process of hot strip rolling was studied,and the state space model of a gauge-looper integrated system in tandem hot rolling was established.Secondly,DMPC strategy based on neighborhood optimization was proposed,which fully considered the coupling relationship in this integrated system.Finally,a series of experiments simulating disturbances and emergency situations were completed with actual rolling data.The experimental results showed that the proposed DMPC control strategy had better performance compared with the traditional proportional-integral control and centralized model predictive control,which is applicable for the gauge-looper integrated system.
