AVALIAÇÃO NUMÉRICA DA DISTRIBUIÇÃO DE TEMPERATURA EM CILINDROS DE LAMINAÇÃO
NUMERICAL EVALUATION OF TEMPERATURE DISTRIBUTION IN THE ROLLING MILL ROLLS
Lira Junior, José Claudino de; Henríquez, Jorge Recarte; Dutra, José Carlos C.
http://dx.doi.org/10.4322/tmm.2013.023
Tecnol. Metal. Mater. Min., vol.10, n2, p.170-176, 2013
Resumo
Nos processos de laminação a quente, ocorrem mudanças no perfil dos cilindros de laminação (expansão e contração) e desgastes constantes devido aos esforços mecânicos e aos ciclos térmicos de aquecimentos/resfriamentos contínuos a que são submetidos pelo contato material-cilindro e pelo sistema de resfriamento por jatos de água na sua superfície, diminuindo a sua vida útil. Este trabalho tem como objetivo apresentar um modelo computacional para simular o comportamento térmico dos cilindros de laminação. O modelo foi elaborado utilizando o método dos volumes finitos para um sistema bidimensional transiente e permite calcular a distribuição de temperatura do cilindro em diversas condições de serviço. Investiga-se a influência da vazão e da temperatura da água de resfriamento sobre a distribuição de temperatura no cilindro. Os resultados mostram que a temperatura da água tem maior influência do que a vazão no controle da temperatura superficial dos cilindros
Palavras-chave
Cilindros de laminação, Simulação numérica, Transferência de calor
Abstract
In hot rolling processes occur changes in the profile of the rolling mill rolls (expansion and contraction) and constant wear due to mechanical stress and continuous thermal cycles of heating/cooling caused by contact rolled material- working roll and the cooling system by water jets in their surface, decreasing their lifetime. This paper presents a computational model to simulate the thermal performance of rolling mill rolls. The model was developed using the finite volume method for a transient two-dimensional system and allows calculating the temperature distribution of the rolling mill rolls under various conditions of service. Here it is investigated the influence of flow rate and temperature of the cooling water on the temperature distribution. The results show that the water temperature has greater influence than the water flow to control the surface temperature of the cylinders.
Keywords
Rolling mill rolls, Numerical simulation, Heat transfer
Referências
1 Guerrero MP, Flores CR, Pérez A, Colás R. Modelling heat transfer in hot rolling work rolls. J Mater Process Tech. 1999;94:52-59. http://dx.doi.org/10.1016/S0924-0136(99)00083-7
2 Lee P, Choi H, Lee S. The effect of nozzle height on cooling heat transfer from a hot steel plate by an impinging liquid jet. ISIJ Int. 2004;44:704-709. http://dx.doi.org/10.2355/isijinternational.44.704
3 Rizzo EMS. Processo de laminação dos aços: uma introdução. São Paulo: Associação de Brasileira de Metalurgia e Materiais; 2007.
4 Hill DR, Gray LE. Colling of work rolls in hot rolling mills. Iron Steel Eng. 1981;58:57-62.
5 Stevens PG, Ivens, K.P., Harper, P. Increasing work-roll life by improved roll-cooling practice. J Iron Steel I. 1971;209:1-11.
6 Raudenský M, Horský J, Kotrbácek P, Pohanka M. Cooling of rolls used in hot rolling of long products. Birmighm: IOM Communications; 2007.
7 Li HC, Li Jiang ZY, Tieu AK, Sun WH, Wei DB. Experimental study on wear and friction of work roll material with 4% Cr and added Ti in cold rolling. Wear. 2011;271:2500-2511. http://dx.doi.org/10.1016/j.wear.2010.11.053
8 Pérez A, Corral RL, Fuentes R, Colás R. Computer simulation of the thermal behaviour of a work roll during hot rolling of steel strip. J Mater Process Tech. 2004;153-154:894-899. http://dx.doi.org/10.1016/j. jmatprotec.2004.04.103
9 Ginzburg VB, Bakhtar FA, Issa RJ. Application of coolflex model for analysis of work roll thermal conditions in hot strip mills. Iron Steel Eng. 1997;74:38-45.
10 Saboonchi A, Abbaspour M. Changing the geometry of water spray on milling work roll and its effect on work roll temperature. J Mater Process Tech. 2004;148:35-49. http://dx.doi.org/10.1016/j.jmatprotec.2004.01.038
11 Gradeck M, Kouachi A, Borean JL, Gardin P, Lebouché M. Heat transfer from a hot moving cylinder impinged by a planar subcooled water jet. Int J Heat Mass Tran. 2001;54:5527-5539.
12 Azene YT, Roy R, Farrugia D, Onisa C, Mehnen J, Trautmann H. Work roll cooling system design optimisation in presence of uncertainty and constrains. J Manuf Sci Tech. 2010;2:290-298. http://dx.doi.org/10.1016/j. cirpj.2010.06.001
13 Benasciutti D, Brusa E, Bazzaro G. Finite elements prediction of thermal stresses in work roll of hot rolling mills. Procedia Eng. 2010;2:707-716. http://dx.doi.org/10.1016/j.proeng.2010.03.076
14 Lu L, Wang Xi, Gao Z, Jiang Y. Influence of the contact pressure on rolling contact fatigue initiation of 1070 steel. Procedia Eng. 2011;10:3000-3005. http://dx.doi.org/10.1016/j.proeng.2011.04.497
15 Chen W-L, Yang Y-C. Inverse problem of estimating the heat flux at the roller/workpiece interfaceduring a rolling process. Applied Thermal Engineering. 2010;30:1247-1254. http://dx.doi.org/10.1016/j.applthermaleng.2010.02.007
16 Weisz-Patrault D, Ehrlacher A, Legrand N. Evaluation of temperature field and heat flux by inverse analysis during steel strip rolling. Int J Heat Mass Tran. 2012;55:629-641. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2011.10.048
17 Cetlin PR, Helman H. Fundamentos da conformação mecânica dos metais. 2. ed. São Paulo: Artliber; 2005
18 Biswas SK, Chen S-J, Satyanarayana A. Optimal temperature tracking for accelerated cooling processes in hot rolling of steel. Dynam Control. 1997;7:327-340. http://dx.doi.org/10.1023/A:1008268310234
19 Churchill SW, Chu HHS. Correlating equations for laminar and turbulent free convection from horizontal cylinder. Int J Heat Mass Tran. 1975;18:1049-1053. http://dx.doi.org/10.1016/0017-9310(75)90222-7
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