Disclosed herein is a method and apparatus for improving the heating capacity of steam-heated hot plates, and in particular, to steam-heated hot plates used in the corrugating industry. One or more separators and thermocompressors are added to the output of the hot plates to separate blow through steam from condensate and pressurize and inject the steam back into the hot plates.

A method of making a molded paper web. The method includes forming a nascent web from an aqueous solution of papermaking fibers, moving a dewatered web on a transfer surface, and applying a vacuum at a molding zone defined between the transfer surface and a molding roll. The molding roll includes a permeable patterned surface on an exterior of the molding roll. The method also includes transferring the dewatered web from the transfer surface to the permeable patterned surface at the molding zone. The vacuum is applied during the transferring of the dewatered web, and the papermaking fibers of the dewatered web are (i) redistributed on the permeable patterned surface and (ii) drawn into a plurality of recess of the permeable patterned surface, in order to form the molded paper web.

A method of making a molded paper web. The method includes forming a nascent web from an aqueous solution of papermaking fibers, moving a dewatered web on a transfer surface, and applying a vacuum at a molding zone defined between the transfer surface and a molding roll. The molding roll includes a permeable patterned surface on an exterior of the molding roll. The method also includes transferring the dewatered web from the transfer surface to the permeable patterned surface at the molding zone. The vacuum is applied during the transferring of the dewatered web, and the papermaking fibers of the dewatered web are (i) redistributed on the permeable patterned surface and (ii) drawn into a plurality of recess of the permeable patterned surface, in order to form the molded paper web.

A method of making a fibrous sheet. The method includes forming a nascent web from an aqueous solution of papermaking fibers, moving a dewatered web on a transfer surface, and applying a vacuum at a molding zone defined between the transfer surface and a molding roll. The molding roll includes a permeable patterned surface on an exterior of the molding roll. The method also includes transferring the dewatered web from the transfer surface to the permeable patterned surface at the molding zone. The vacuum is applied during the transferring of the dewatered web, and the papermaking fibers of the dewatered web are (i) redistributed on the permeable patterned surface and (ii) drawn into a plurality of recess of the permeable patterned surface, in order to form a molded paper web. The method further includes drying the molded paper web in a drying section to form a fibrous sheet.

The invention relates to a method of producing a structured fibrous web of paper suitable for tissue products. The method comprises forming a fibrous web and conveying the formed fibrous web on a water receiving felt (5) to a dewatering nip. An endless steel belt (11) with a smooth steel surface is passed through the nip together with the fibrous web and the water receiving felt (5) wherein the endless steel belt is heated by heaters (HE.sub.U, HE.sub.L). After the dewatering nip, the fibrous web is conveyed by the endless steel belt (11) to an endless textured fabric (12) which is permeable to air and to which the web is transferred from the endless steel belt (11) in a transfer nip. The textured fabric (12) runs at a lower speed than the endless belt (11). After the transfer to the textured fabric (12), the fibrous web is carried by the textured fabric (12) to a drying cylinder (17). The transfer nip is formed by two rolls of which one is a suction roll within the loop of the textured fabric. The transfer nip has a length which is 5 mm-40 mm. The endless steel belt (11) has a width that exceeds the width of the textured fabric (12). The invention also relates to a corresponding machine.

The invention relates to a method of producing a structured fibrous web of paper suitable for tissue products. The method comprises forming a fibrous web and conveying the formed fibrous web on a water receiving felt (5) to a dewatering nip. An endless steel belt (11) with a smooth steel surface is passed through the nip together with the fibrous web and the water receiving felt (5) wherein the endless steel belt is heated by heaters (HE.sub.U, HE.sub.L). After the dewatering nip, the fibrous web is conveyed by the endless steel belt (11) to an endless textured fabric (12) which is permeable to air and to which the web is transferred from the endless steel belt (11) in a transfer nip. The textured fabric (12) runs at a lower speed than the endless belt (11). After the transfer to the textured fabric (12), the fibrous web is carried by the textured fabric (12) to a drying cylinder (17). The transfer nip is formed by two rolls of which one is a suction roll within the loop of the textured fabric. The transfer nip has a length which is 5 mm-40 mm. The endless steel belt (11) has a width that exceeds the width of the textured fabric (12). The invention also relates to a corresponding machine.

There is provided a method of producing a paper having a grammage according to ISO 536 of 50-250 g/m2, a Gurley value according to ISO 5636-5 of above 15 s and a stretchability according to ISO 1924-3 in the cross direction of at least 8%, said method comprising the steps of: a) providing a pulp, preferably sulphate pulp; b) subjecting the pulp to refining; c) diluting the pulp from step b) and discharging the diluted pulp at a discharge rate to a forming wire to form a paper web, wherein the speed of the forming wire is at least 7 m/min higher or at least 7 m/min lower than the discharge rate; d) pressing the paper web from step c); e) drying the paper web from step d), which drying comprises a step of compacting the paper web in a Clupak unit.

A drying roller includes at least a cylindrical cylinder shell, two caps which are attached to both sides of the cylinder shell, and two journals which are indirectly fastened to the caps by way of a hollow shaft which is connected to the caps or are directly fastened to the caps, wherein the cylinder shell and the caps are welded to one another by way of an annular weld seam. The weld seam has a joint having at least two mutually opposite and parallel flange regions which are mutually spaced apart. A method for manufacturing a drying roller is also described.

A method for operating a heating group subsystem of a machine for the production or treatment of a fibrous web. The heating group subsystem includes a first heating group and a last heating group and at least one additional heating group; in each case having at least one device that is heated with pressurized heating steam. Viewed in a direction of travel, the fibrous web is fed first through the first heating group, then through the at least one additional heating group, and thereafter through last heating group. The steam pressure of the heating steam of the at least one additional heating group is adjusted lower than the respective steam pressure of the heating steam of first heating group and of last heating group.

A method of making a fibrous sheet. The method includes forming a nascent web from an aqueous solution of paper-making fibers, moving a dewatered web on a transfer surface, and applying a vacuum at a molding zone defined between the transfer surface and a molding roll. The molding roll includes a permeable patterned surface on an exterior of the molding roll. The method also includes transferring the dewatered web from the transfer surface to the permeable patterned surface at the molding zone. The vacuum is applied during the transferring of the dewatered web, and the papermaking fibers of the dewatered web are (i) redistributed on the permeable patterned surface and (ii) drawn into a plurality of recess of the permeable patterned surface, in order to form a molded paper web. The method further includes drying the molded paper web in a drying section to form a fibrous sheet.