Hyperroll-RCZ is a stiff roller with zero porosity and with higher thermal conductivity, intended to reduce the roller deformation in the rapid cooling zone.
The rapid cooling zone has really specific characteristics which must be taken into account and analyzed in detail. In this area, tiles undergo a really fast and sensitive process which can ruin their final quality. The upper side of the roller is in contact with the hot tiles coming from the firing zone; meanwhile the lower side is in contact with the cold air. The hot surface expands due to the temperature.
This difference in temperatures and expansions are mainly responsible for the deformation of the rollers in the fast cooling zone. When searching for the best roller material for this area, it is important to analyze two main factors:
Thermal conductivity: to transfer the heat around and alongside the roller reducing the temperature difference between the upper and lower part. This technique ensures that the internal thermal tension of the roller (thermal load) is reduced.
Bending strength: A higher Module of Elasticity means that the roller can better resist the mechanical load as the tiles pass into the rapid cooling zone, they are thus less structurally and dimensionally stressed. Problems associated with transport of the tiles through the kiln are thus greatly reduced.