| Roll profile electromagnetic control technology belongs to roll profile flexible control technology,which has the ability of roll gap shape control and can be applied to the strip flatness control of rolling mill.Multi-section and flexible roll gap control is the feature of this technology,and is also the difficulty and hot spot of its research.Based on the roll profile electromagnetic control characteristics of the basic control component,a multisection micro scale roll profile electromagnetic control technology is proposed to solve the outstanding problems such as unclear technical principle,imperfect index system,and incomplete multi-section control theory.Taking basic control components as typical objects,it focuses on solving key problems such as thermal-force bulging analysis,multi-flux control energy efficiency evaluation,electromagnetic stick space structure design,component loading configuration,and internal and external cooling mechanism setting.Firstly,the roll profile composition and the magneto-thermal-mechanical coupling relationship of the roll profile electromagnetic control process were analyzed,and an analytical model of combined thermal-force bulge was constructed,and the thermal-force bulging principle of the roll profile electromagnetic control technology was revealed.Based on the magnetic flux characteristics of induction heating,transverse and longitudinal magnetic flux forms were proposed.In addition,based on the characteristics of roll profile,an evaluation method for electromagnetic control roll profile is established,and the characteristics of roll profile are summarized,which lays a foundation for the development of multi-section roll profile electromagnetic regulation technology.Secondly,the multi-flux simulation models of the roll profile electromagnetic control technology were established.From the perspective of transverse and longitudinal magnetic flux,the influence law of current density,current frequency and initial temperature on regulating energy efficiency were studied.According to the variation law of parameters,the intersection relationship of energy efficiency under two kinds of magnetic flux forms was explored.From the angle of transverse and longitudinal magnetic flux,three magnetic focusing forms were proposed,and the influence laws of magnetic focusing forms on regulating energy efficiency were analyzed,which can provide support for the selection of magnetic flux forms and the equivalence between magnetic flux forms.Thirdly,the axial,radial and circumferential structure characteristic parameters were proposed based on the spatial structure characteristics of basic control components.The effects of the axial and radial structure characteristic parameters on the regulation energy efficiency were studied.Based on the circumferential simulation model of roll profile electromagnetic control,the temperature ratchet and force ratchet phenomena were studied under the influence of the slot amount and slot size,and the influences of the two on the roll profile control ability were explored,which can provide guidance for the design and optimization of roll profile electromagnetic control elements.Then,according to the heat transfer law between electromagnetic control roll and environment,the characteristics of roll end cooling control,roll external sectional cooling control and roll internal cooling control were summarized.The effects of roll end structure,external sectional cooling and internal cooling on the regulation energy efficiency were analyzed,which can provide a basis for the parametric prediction of electromagnetic control roll profile of basic control components.Finally,the parametric influence relation of the control ability of the basic control element were sorted out and summarized,the superposition relation of roll profile under typical multi-section control mode such as double-bar control and three-bar control is analyzed,and the formation mechanism of roll profile under multi-section electromagnetic control is revealed.Then,the multi-section control method of roll profile electromagnetic control was proposed,and the method and process of roll shape presetting based on the target roll profile are discussed.Aiming at the connection between roller profile control ability and electromagnetic control parameters,the calculation model of electromagnetic rod temperature rise power and electromagnetic control parameters was derived based on dimensional analysis theory.Based on the self-built flatness electromagnetic control experiment platform,the feasibility of multi-section electromagnetic control roll shape preset method was verified,and the flatness control effect of the technology was analyzed,which enriched the theory of the technology and established the prototype of multi-section microscale roller shape electromagnetic control technology system. |
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