Apparatus and process for the smoothing of a material web

An apparatus for smoothing of a material web comprising:

• at least one deflection adjustment roll having a soft surface;
• at least one heatable endless band having a hard and smooth surface, said at least one heatable endless band being arranged into a band loop having an inner surface;
• at least one support surface located within the band loop, and said at least one heatable endless band being guided over said at least one support surface;
• said at least one deflection adjustment roll and said at least one heatable endless band being arranged to form at least one smoothing zone structured and arranged to act on the material web;
• at least one heating medium supply device positioned adjacent said inner surface and adapted to heat said inner surface and to create a liquid film for hydrodynamic lubrication between said at least one support surface and said at least one heatable endless band;
• and
• said at least one heating medium supply device is adapted to supply a hot gaseous medium onto said inner surface of said at least one heatable endless band, whereby said liquid film for hydrodynamic lubrication is formed by condensed heating medium.

An apparatus smoothing of a material web comprising:

• at least one deflection adjustment roll having a soft surface;
• at least one heatable endless band having a hard and smooth surface, said at least one heatable endless band being arranged into a band loop having an inner surface;
• at least one support surface located within the band loop, and said at least one heatable endless band being guided over said at least one support surface;
• said at least one deflection adjustment roll and said at least one heatable endless band being arranged to form at least one smoothing zone structured and arranged to act on the material web;
• at least one heating medium supply device positioned adjacent said inner surface and adapted to heat said inner surface and to create a liquid film for hydrodynamic lubrication between said at least one support surface and said at least one heatable endless band;
• said at least one heating device comprising a controlled zone-wise heating unit extending over a width of the web, wherein said heating medium directed onto said at least one heatable endless band is zone controllable;
• and
• said at least one heating device comprising one of a zone-controlled steam moistener and a zone-controlled steam blowing box.

A process for smoothing of a material web in an apparatus that includes at least one deflection adjustment roll having a soft surface, at least one heatable endless band having a hard and smooth surface in which the at least one heatable endless band is arranged into a band loop having an inner surface, at least one support surface located within the band loop, in which the at least one heatable endless band is guided over said at least one support surface, the process comprising:

• positioning said at least one deflection adjustment roll and said at least one heatable endless band to form at least one smoothing zone adapted to act on the material web;
• heating the inner surface with a heating medium;
• and
• creating, from the heating medium, a liquid film for hydrodynamic lubrication between the at least one support surface and the at least one heatable endless band.

A process for smoothing of a material web in an apparatus that includes at least one deflection adjustment roll having a soft surface, at least one heatable endless band having a hard and smooth surface in which the at least one heatable endless band is arranged into a band loop having an inner surface, at least one support surface located within the band loop, in which the at least one heatable endless band is guided over said at least one support surface, the process comprising:

• positioning said at least one deflection adjustment roll and said at least one heatable endless band to form at least one smoothing zone adapted to act on the material web;
• heating the inner surface with a heating medium;
• and
• creating, from the heating medium, a liquid film for hydrodynamic lubrication between the at least one support surface and the at least one heatable endless band;
• heating the inner surface with a hot gaseous medium;
• and
• condensing the hot gaseous medium on the inner surface, whereby the liquid film is created.