Roval is the market leading specialist in filled rolls for calendering. The rovalrolls technology is widely used for the calendering and embossing of paper and textiles.
The supercalendering process influences the surface characteristics of the paper (eg gloss, smoothness, density, porosity), depending on the nip pressure, the roll surface temperature, the process speed and the elastic behaviour of the filled roll cover.
Many types of coated and special papers are supercalendered to improve their finish.
The operation of transferring a pattern (for example imitation leather, geometric designs, logos etc).from an engraved roll to the paper or fabric
The achieved effect depends on the engraved pattern relief, nip pressure, roll surface temperature, process speed and the elastic behaviour of the filled roll cover. The paper or fabric are embossed to enhance their appearance or structure.
The choice of rovalrolls cover material (elastossimo, elastoglaz, excellrolls) is defined according to the operating conditions of your calender (speed, humidity, temperature, linear load), and taking account of the type of fabric to be calendered (natural, sythetic, nonwoven) and the desired finish (e.g. soft hand, sheen, chintz, reduced permeability). This cover engineering determines the production parameters for filling the roll and for the roll’s efficiency on your specific calendering process.
Rovalrolls sprinks steel shaft technology guarantees the operational safety and geometric precision of the covered roll. Knowing the exact shaft design enables accurate calculation of the required camber for textile and embossing calenders.
Process parameters such as cover material moisture content, interference fit and density are calculated according to the cover material properties and the calender running conditions.
These key parameters are continually controlled throughout the production process, allowing instant correction of any out of tolerance. In this way the filled roll quality is guaranteed, and the uniformity of the linear load profile in the calender nip is assured.