Valmet Paper Machinery Inc.

Metso Paper Inc.

Valmet Corporation

Kari Sipi

Kari Juppi

Juha Lipponen

Antti Heikkinen

Harri Kuosa

Mikko Tani

Eero Suomi

Markku Kyyts&ouml;nen

Ari Lassila

Johan Grön

Timo Viitanen

Timo Kiema

Juhani Partanen

Mika Tammenoja

A paper or paperboard web (W) is precalendered. A web that has undergone earlier dewatering stages is calendered to attain a suitable surface for the coating process. The web is calendered (C) one-sidedly in such a manner that the absorption level of the second side (W) of the web entering the calendering, which is higher than the absorption level of the first side (W), is reduced in the calendering nearly to the same level or at least to the same level with the first side (W).

Precalendering method, finishing method and apparatus for implementing the methods

A method and apparatus for producing calendered paper by an on-line manufacturing system comprising at least a paper machine and a multi-nip calender. The method comprises following steps: removing water from a formed paper web by pressing, drying the pressed paper web by at least one dryer, calendering the dried web by the multi-nip calender, measuring a cross-machine moisture profile or a variable relative thereto, and altering the moisture of the web so that the moisture profile of the web in the cross-direction is even when the web enters the first nip of the calender.

Method for producing calendered paper

An on-machine calender device intended to be on-line connected to a paper machine. The calender comprises a number of subsequent calendering nips, through which the web (W) to be calendered can be passed. The nips are formed between a soft calender roll and a hard calender roll or between two soft calender rolls. The calender is composed of one or several, for example two, subsequent calender modules (M.sub.1, M.sub.2). The modules comprise one counter-roll (10, 20) and at least two soft calendering rolls (11, 12, 13; 21, 22, 23), which are placed at both sides of the counter-roll (10, 20) in the direction of running of the web (W). The calender rolls (10, 11, 12, 13;20, 21, 22, 23) are dispaceable in relation to each other so that the threading of the web (W) can be carried out as a straight run, for which purpose an open passage is opened through the calender.

Calender device for on-line connection to a paper machine

A calender comprises at least one pair of rolls through which a web to be calendered runs. One roll in each pair of rolls is a hard roll which is a heated metal roll, and the other roll in each pair of rolls is a roll provided with a resilient coating. The face of the roll with the resilient coating is also heated to a high temperature, advantageously to the same temperature as the heated metal roll.

Roll for use in calendering a web

Growing community of inventors

Espoo, Finland

Kari Sipi