摘要 |
A roller for thermal pressure treatment of web-type media such as paper or non-wovens, provided with an inner heating system and comprising a base body made of hardened and tempered wrought steel or alloyed cast iron, an intermediate layer applied to the surface thereof and a hard wearing layer applied thereon. Peripheral bores or canals extending parallel to the axis are arranged in the base body of the roller at a regular distance from the surface, being distributed in a regular manner on the circle formed about the roller axis. The materials used and the arrangement of the peripheral bores are such that the roller can be used in calendars in a method wherein the surface temperatures of the roller exceed 140° C., the heating capacity is more than 35 kW/m2, operational speeds are more than 1200 m/min, line pressures are greater than 250 kN/m and the processed webs of material weigh more than 45 g/m2 and have a degree of moisture of over 5%. |