RCX for extreme conditions

HOB Certec is the roller producer having the most complex and widest range of the roller types for the kilns offering to the client the best choice possible based on their requirements. The whole range is completed by standard, technical and hypertechnical rollers for any kind of production.

Beside the last newcoming hypertechnical roller types as Hyperroll IQ and Hyperroll XT, HOB CerTec is the only one on the market having four types of rollers just for the rapid cooling zone, giving to the client the best suitable choice and solution for rapid cooling zone based on the product they produce. All the rollers for rapid cooling zone greatly improves the quality of the tile production. Thanks to this, you can get a higher percentage of first quality tiles, because less tiles are bent, have internal tensions, irregular structures or hairline cracks on their surface. Moreover, a better kiln control is assured by the more precise transport of the tiles.

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.

❖ Superringroll

The design of the Superringroll is the best roller solution to avoid the deformation in this area by reducing the contact area between the roller and the tile. The Superringroll reduces the internal thermal tension of the roller and tile allowing a more uniform heat distribution between the tile and roller due to an excellent flowing of the cold air. It is considered for the production of a wide range of standard tiles.

A stiff roller with zero porosity and with higher thermal conductivity and high MOE of 120 GPa, intended to reduce the roller deformation in the rapid cooling zone suitable for production of thick tiles with a weight of 45 kg/sqm.

Hyperroll GR

It is a high-performance roller, engineered to withstand the demanding working conditions in the rapid cooling zone. With almost zero porosity and very high thermal conductivity, is designed to prevent deformation and preserve the quality of tiles undergoing a fast and delicate process. GR also boasts a very high bending strength thanks to its superior modulus of elasticity of 120 GPa. This enables it to resist mechanical loads as tiles pass through the rapid cooling zone, minimizing structural and dimensional stress, suitable for production of thick tiles.

❖ Hyperroll RCX

HOB CerTec’s newest hyper-technical roller Hyperroll RCX is a top-performance roller designed for use in severe conditions in the rapid cooling zone. With an MOE of 185 GPa and a thermal conductivity of 9.6 W/m.K-1, it is the best possible solution for demanding applications where both strength and heat transfer performance are critical. With more than double thermal conductivity compared to standard (grey) cooling rollers, it offers superior cooling capabilities that help to cool down the tiles faster, more intensively and uniformly without any side effects.

During the fast-cooling process, the roller’s upper side is exposed to hot tiles from the firing zone, while the lower side is in contact with cold air. The resulting temperature differences and expansions can cause deformation of other/grey rollers, but HOB CerTec‘s roller’s superior thermal conductivity transfers the heat effectively, reducing inner tension in the tiles and improving their planarity.

In addition to its extra high bending strength and excellent heat transfer performance, the Hyperroll RCX also boasts exceptional resistance against chemical attacks. Its low porosity ensures that it can withstand exposure to harsh chemicals with minimum degradation.

Features:

• Extra high mechanical strength with MOE 185 GPa

• Excellent thermal conductivity: 9.6 W/m.K-1

• Suitable for extreme conditions in the rapid cooling zone

• Long service life thanks to high wear resistance.◆