Paper machine and method for manufacturing paper

Abstract

A paper machine comprises a clothing that exhibits a three-dimensional structure for structuring a fiber web. A paper machine (1) comprises a wet end (2) comprising a wire section (5) comprising a forming wire (7, 8) for forming a fiber web (12), a clothing (16), being air and water permeable, and dewatering unit (20); a drying section (3) comprising a drying surface (24); and a transfer roll (23) arranged for interacting with the drying surface at a transfer nip (25) for transferring the fiber web from the wet end to the drying section. The fiber web is supported by the clothing from the wire section all the way to and through the transfer nip. The clothing exhibits a three-dimensional structure for structuring the fiber web. Independent claims are also included for: (1) a method for manufacturing paper in a paper machine, comprising forming a fiber web in a wire section; supporting the fiber web by an air and water permeable clothing from the wire section to a drying section, and dewatering the fiber web within this distance by a dewatering unit; transferring the fiber web from the clothing to a drying surface of the drying section; and removing the fiber web from the drying surface, where the step of structuring the fiber web by a three-dimensional structure of the clothing; and (2) a paper manufactured by the inventive method.

Description

technical field [0001] The present invention relates to a papermaking machine for producing a paper fiber web without through-drying (TAD) or pressing, the papermaking machine comprising: [0002] a wet section comprising a wire section, a clothing permeable to air and water and at least one dewatering unit for dewatering said fibrous web, said wire section comprising at least one web forming, [0003] a drying section comprising a drying surface for drying said fibrous web, and [0004] a transfer roll arranged to interact with said drying surface at a transfer nip to transfer said fibrous web from said wet section to said drying section, [0005] Therein, the fibrous web is supported by the clothing from the wire section to and through the transfer nip. [0006] Furthermore, the present invention relates to a method for producing paper without through-drying (TAD) or pressing in a paper machine, the method comprising the steps of: [0007] forming a fiber web in the wire...

AI Technical Summary

Problems solved by technology

However, the paper machine also has some disadvantages

Due to the sandwich structure of the web, it has proven difficult to achieve ideal dewatering of the paper web before the dryer section, which in turn limits the manufacturing speed and increases the drying requirements in the dryer section

Furthermore, the sandwich structure has an adverse effect on the bulk of the final web

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