Valmet Corporation

Valmet Paper Machinery Inc.

Valmet Technologies Oy

Juha Kivimaa

Jorma Laapotti

Mika Viljanmaa

Juhani Pajula

Martti Hirsimaki

Mikko Karvinen

Pekka Taskinen

Antti Poikolainen

Pertti Heikkila

Hans Sundqvist

Seppo Luomi

Antti Leinonen

Matti Lares

Henrik Pettersson

Juan Cecchini

Kari Lamminmäki

Lauri Suvanto

Martti Hipsimaki

Erkki Kiilavuori

Risto Salminen

Hannu Niemikko

Tapio Lento

Jorma Lapotti

Eveliina Karjala

Juha Kovanen

Petri Lewandowski

Antti MÄNTYNEN

Sampo Immonen

Sari Behm

Mikko MAJAMÄKI

Toni Tikka

Jarmo Oikarinen

Tapio Koski

Timo Valkama

Harri MikkilÄ

The invention relates to a method for forming a three-layer board web, preferably a folding box board (FBB) or a solid bleached (sulfate) board (SBS), in a forming section () comprising a multilayer headbox () and a forming unit (). In the method the layers of the three-layer board web are first formed of pulp suspension in the multilayer headbox () and fed to only one forming unit (), a gap former where the pulp suspension from the multilayer headbox is fed to a gap between lower and upper wires for water removal and for joining the layers of the three-layer board web and where water is first removed by a non-pulsating forming shoe ().

Method of forming a three-layer board web and a forming section of forming a three-layer board web

The invention relates to a device and method in a paper machine for guiding a web and in particular in guiding a leader of the web. The device operates in a paper machine in the area between a center roll of the press section and a separate press nip in the press section. The separate press nip is formed between a smooth-faced upper roll and a hollow-faced lower roll. Around this lower roll, a lower felt of the separate press is placed and runs from a suction-transfer roll placed at the proximity of the center roll as a straight run into the separate press nip. At the initial end of the straight run of the felt of the separate press nip, in connection with the guide roll, air-transfer devices are arranged, by whose means a reduced pressure is produced at least across the width of the leader in connection with a closing inlet nip between the felt and the leader and/or in connection with an opening outlet nip defined between the guide roll and the straight run of the felt.

Method and device for guiding a leader of a web in a paper machine

A press section for a paper machine employing at least two press nips placed one after the other. Of these nips, at least the first nip is an extended nip or an extended roll nip. The last nip in the press section is placed on a level higher than the preceding nip. The first nip and/or, when more than two nips are employed, the nip that immediately precedes the last nip is/are provided with two press fabrics that receive water. The paper web is transferred on the lower fabric of the two press fabrics onto an upper fabric of the last nip. On the lower face of the upper fabric, the web is transferred into the last nip. After the web transfer point, the upper fabric of the last nip has a relatively short upwardly inclined run. After this, the upper fabric is turned and guided by the lower roll of the last nip over a considerable sector thereof. The last nip is placed after, or at the vicinity of, the uppermost point of the lower roll that forms the last nip. The point of transfer of the web onto the drying wire of the first group in the dryer section following after the press section is placed underneath the level of the last nip.

Press section of a paper machine employing two separate press nips

A hood for a wire part and/or a press section in a paper/board machine including walls and a ceiling which form a closed hood around the wire part and/or press section, air-conditioning or another air-control system being arranged in connection with the hood. The hood walls have outer and inner walls which define an air duct therebetween for passing a replacement air flow into the interior of the hood, preferably toward a middle area of the paper machine, through openings in the inner wall, the replacement air keeping the interior of the hood substantially dry and clean. The walls of the hood include a vertical side wall at the driving side, which wall is preferably fixed, and a tending-side vertical side wall and a ceiling formed as a single wall which is preferably L-shaped and displaceable. The displaceable hood wall at the tending side has two parts so that the first hood wall is placed by the wire section and the second hood wall is placed by the press section.

Hood for a wire part and for a press section

Method and device in the manufacture of paper or board for dewatering of a paper web that is being manufactured. The paper web is transferred from a forming wire onto a wire in the drying section while constantly on support of a fabric that receives water, a transfer fabric, or of any other, corresponding transfer surface as a closed draw, at a particularly high speed, which is higher than about 25-30 m/s. Dewatering of the paper web is carried out by means of at least two subsequent press nips, of which nips at least one press nip is a so-called extended-nip zone, whose length in a machine direction is larger than about 100 mm. The extended-nip zone is formed in connection with a mobile flexible press-band loop. The distribution of the compression pressure employed within said extended-nip press zone is regulated and/or selected both in the transverse direction of the web and in the machine direction so as to set or to control the different profiles of properties of the web.

Device for dewatering of a paper web including prepressing with extended

The invention relates to a device in a paper machine for guiding a web and in particular in guiding a leader of the web. The device operates in a paper machine in the area between a center roll of the press section and a separate press nip in the press section. The separate press nip is formed between a smooth-faced upper roll and a hollow-faced lower roll. Around this lower roll, a lower felt of the separate press is placed and runs from a suction-transfer roll placed at the proximity of the center roll as a straight run into the separate press nip. At the initial end of the straight run of the felt of the separate press nip, in connection with the guide roll, air-transfer devices are arranged, by whose means a reduced pressure is produced at least across the width of the leader in connection with a closing inlet nip between the felt and the leader and/or in connection with an opening outlet nip defined between the guide roll and the straight run of the felt.

Device for guiding a leader of a web in a paper machine

Method for dewatering of a paper web by pressing using an extended nip

The invention concerns a method and a device for removing water out of the perforations in a suction roll wherein a doctor blade is brought into contact with the face of the suction roll. The doctor blade is mounted with its slat face in such an angular position in relation to the face of the suction roll that the angle between the face plane of the doctor blade and the tangential direction of the face of the suction roll, when the tangent is drawn at the contact point between the tip of the doctor blade and the face of the suction roll, is from about 2.degree. to about 10.degree.. In the method, water is removed by means of the inlet-side surface plane of the doctor blade, the inlet side being seen in the sense of rotation of the suction roll, and the water is allowed to flow smoothly over the doctor blade out of contact with the construction. According to the invention, water may be additionally removed by means of a suction effect out of the area between the slat face of the doctor blade and the suction roll, negative pressure being produced in the space. The negative pressure produces flow of water out of the perforations or grooves in the suction roll.

Doctor for a suction roll

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Jyvaskyla, Finland

Juha Kivimaa