ANÁLISE COMPARATIVA DE CARGAS DE LAMINAÇÃO A QUENTE INDUSTRIAIS COM AS OBTIDAS ATRAVÉS DE MODELAMENTO MATEMÁTICO
COMPARATIVE ANALYSIS OF INDUSTRIAL HOT ROLLING LOADS AND THOSE OBTAINED THROUGH MATHEMATICAL MODELING
Evaldo Diniz Dias, Jose Adilson de Castro, Fabio de Oliveira Araújo, Carlos Roberto Xavier, Alexandre Pimentel Sampaio
Resumo
Uma análise comparativa entre as cargas de laminação calculadas através dos modelos de Sims, Orowan-Pascoe e Ekelund é realizada a fim de verificar o melhor desempenho, frente aos valores registrados durante o processamento de aços C-Mn e ao nióbio em um trem acabador de tiras a quente industrial. Para determinação da tensão média de escoamento são utilizadas as equações de Shida, Poliak & Siciliano, Siciliano, Marini & Bruna, Siciliano, Leduc & Hensger, Misaka e Siciliano & Jonas . Na comparação direta entre os valores calculados e os reais, os melhores níveis de precisão são obtidos quando os modelos de previsão de carga são combinados a equação de Shida, respectivamente Sims, Orowan-Pascoe e Ekelund. Neste trabalho são propostos fatores de correção visando obter maior previsibilidade para o processo industrial durante a laminação de acabamento. Com a aplicação dos fatores de ajuste as equações de previsão de carga apresentaram erros médios globais no trem de acabamento, variando entre 4,3 e 5,6% para os aços C-Mn e 4,6 e 6,3% para aços microligados ao nióbio.
Palavras-chave
Abstract
A comparison between the rolling loads calculated through the theoretical models of Sims, Orowan-Pascoe and Ekelund is performed in order to verify the performance of the models compared to the real values recorded during the processing of plain carbon-manganese steels and niobium steels during the finish rolling in the hot strip mill. To determine the hot deformation resistance, the equations of Shida, Poliak & Siciliano, Siciliano, Marini & Bruna, Siciliano, Leduc & Hensger, Misaka and Siciliano & Jonas are used. In the direct comparison between the calculated values and the actual values the best level of precision is obtained when the load prediction models are combined with the Shida equation, respectively Sims, Orowan-Pascoe and Ekelund. In order to better adjust calculated loads to the reality of the industrial process, adjustment factors are proposed for each of the seven stands of the finishing mill. With the application of the adjustment factors, the load prediction equations presented global mean errors in the finishing mill, varying between 4.3 and 5.6% for C-Mn steels and 4.6 and 6.3% for niobium steels.
Keywords
References
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