Study of the work roll cooling in hot rolling process with regard on service life

Abstract

Operational conditions and many studies confirmed that the work rolls cooling in hot rolling process have
significant impact on damage and service life. The specific approach based on the numerical simulation and
experimental results of the work roll cooling optimization and service life improvement is presented in this paper.
The 3D finite element model was prepared for the numerical simulations of the work roll cooling. The FE model
represents circular sector of the work roll. The model is fully parametric. It is capable to simulate a roll with any
diameter, any thickness. Each of the model parameters can be easily changed based on user requirements. The
stress state is calculated by ANSYS in two steps. At first, the thermal conditions as starting temperature of the roll,
cooling intensity and so on are applied and time dependent thermal analysis is performed. The temperature field
of work roll is obtained from transient thermal analysis and is used as thermal loads in second step. In the second
step structural analysis is carried out. The other relevant boundary conditions as normal, shear and contact
pressure are considered in structural analysis. The Tselikov load distribution model is used for normal and shear
stress distribution in a rolling gap. The boundary conditions for FE analysis are prepared in software MATLAB. All
considered boundary conditions are based on real measured data from hot rolling mills.
The results of the performed analyses are focused on the description of the assessing methodology of the work
rolls cooling on the stresses, deformations and service life of the rolls.