Simulation of the Thermal Conditions of Rolls in a Wide-Strip Hot-Rolling Mill to Determine Their Effective Cooling Conditions

An advanced procedure is developed for the thermal calculation of the rolls in a wide-strip hot-rolling mill (WSHRM). It combines the following two adaptive models: the thermal balance in the active surface layer in a roll per revolution and the thermal balance in the main zones of work and backup rolls with axisymmetric temperature fields with allowance for the heat exchange between a strip, rolls, the coolant, and the environment. In contrast to the well-known models, this advanced procedure calculates the bulk mean temperature and the thermal profile in a roll more accurately, since the temperature drop across the surface layer in this procedure is calculated allowing for the intensities of the contact and convective heat exchange between rolls. Data on the coefficient of heat transfer from rolls to the coolant supplied at an excess pressure of 1.0-1.5 MPa are presented for the first time. This procedure is used in a 2000 WSHRM and improves the transverse profile of hot-rolled strips due to a stabilized thermal profile in rolls.