A method for manufacturing a paperboard structure includes passing a paperboard substrate through a hot-hard calender to yield a calendered paperboard substrate, the hot-hard calender including a nip defined by a thermo-roller and a counter roller, wherein a contact surface of the thermo-roller is heated to an elevated temperature. The method then includes applying a basecoat to the calendered paperboard substrate to yield a basecoated paperboard substrate, the basecoat includes a basecoat binder and a basecoat pigment blend. The method further includes applying a topcoat to the basecoated paperboard substrate.

The present application provides a calender, a floor production line and a production method using the calender, wherein the calender comprises a calendering roller rack and a set of calendering rollers arranged on the calendering roller rack. The set of calendering rollers comprises a plurality of calendering rollers arranged in a line and not vertically. The present application changes the arrangement of the calendering rollers. The calendering rollers are arranged in a line, not vertically. This arrangement reduces the overall height of the calender, decreases the requirements of the calender on the height of the factory building and facilitates long-distance transportation by containers. Using the calender to assemble the floor production line, the height space of the factory building occupied by the production line can be saved.

A process for the production or treatment of a fibrous web, in particular a paper or cardboard web, includes the following steps: a. drying of the fibrous web in a dryer section; b. subsequent cooling of at least one first side of the fibrous web by way of convection cooling, whereby the fibrous web has a temperature of 65 C. or less on at least the first side after cooling, in particular 50 C. and less; c. apply steam to at least the first side of the fibrous web, in particular the temperature on the first side after steam application is at least 70 C., optionally more than 80 C. or 90 C.; and d. treatment of the fibrous web in at least one calendering nip.

Calender for treating web materials, comprising a structure for supporting two heated rollers forming a nip, wherein each roller has surface reliefs (RR) and in an operational setting of the calender the reliefs of one roller are radially opposed to those of the other roller, each roller rotates with a predetermined angular speed around its axis, the rollers are heated by heating means, and each roller undergoes an axial elongation as a consequence of its heating. The calender comprises detection means (E1, E2; IS) adapted to detect the axial elongation of each roller and a programmable control unit (UCP) connected to the detection means and to the heating means. The control unit is programmed to determine the difference between the axial elongations of the rollers and emitting an alarm signal if the absolute value of this difference is greater than a limit value.

Calender for treating web materials, comprising a structure for supporting two heated rollers forming a nip, wherein each roller has surface reliefs (RR) and in an operational setting of the calender the reliefs of one roller are radially opposed to those of the other roller, each roller rotates with a predetermined angular speed around its axis, the rollers are heated by heating means, and each roller undergoes an axial elongation as a consequence of its heating. The calender comprises detection means (E1, E2; IS) adapted to detect the axial elongation of each roller and a programmable control unit (UCP) connected to the detection means and to the heating means. The control unit is programmed to determine the difference between the axial elongations of the rollers and emitting an alarm signal if the absolute value of this difference is greater than a limit value.

A fiber body production apparatus includes a forming mechanism that forms a mixture, a pressing unit that transports the mixture while pressing the mixture, a peeling blade that peels the mixture from the pressing unit, a cleaner that cleans the pressing unit, and a shaping mechanism that shapes the mixture, after a rear end of the mixture passes through the pressing unit, the pressing unit is reversely rotated to move foreign matter adhering to the peeling blade to the pressing unit, after the roller is reversely rotated by a predetermined amount, the pressing unit is rotated forward to transport the foreign matter, compress the foreign matter on the pressing unit, and cause the compressed foreign matter to pass between the peeling blade and the pressing unit, and the cleaner removes the transported foreign matter from the pressing unit.

A process for the production or treatment of a fibrous web, in particular a paper or cardboard web, includes the following steps: a. drying of the fibrous web in a dryer section; b. subsequent cooling of at least one first side of the fibrous web by way of convection cooling, whereby the fibrous web has a temperature of 65 C. or less on at least the first side after cooling, in particular 50 C. and less; c. apply steam to at least the first side of the fibrous web, in particular the temperature on the first side after steam application is at least 70 C., optionally more than 80 C. or 90 C.; and d. treatment of the fibrous web in at least one calendering nip.