Optimal cooling of rolls in hot rolling

A laboratory experimental device was developed to allow full-scale measurements on roll cooling to be carried out. The full-scale tests use a complete configuration of rows of nozzles as in the plant conditions or prepared by a designer. The laboratory approach allows the design to be optimised or to compare old and new solutions. The tests provide a distribution of cooling intensity (heat transfer coefficient and heat flux) at the roll surface. The second step of the optimisation process is the usage of a numerical model for computation of temperature and roll crown in a hot rolling regime. A industrial typical rolling schedule is used to check the efficiency of cooling. A typical application of the experimental–numerical procedure is in improvements of cooling, in intensification of rolling and in design work. The paper shows how this approach can help in “making a decision” related to a prior plant application. Examples of the results and general recommendations for cooling are included.