Valmet Oy

Valmet Paper Machinery Inc.

Olli Tapio

Erkki Koski

Jorma Laapotti

Martti Koponen

Lassi Veijonen

Eero Hannonen

A press section of a paper machine includes a first upper fabric, a pick-up suction roll within a loop of the first upper fabric for transferring a web from the forming wire of the paper machine onto the first upper fabric, a first lower fabric, a lower first press roll within a loop of the first lower fabric forming a first double-felted nip with the pick-up suction roll, a smooth-surfaced center roll, a second press roll situated within the loop of the first upper fabric forming a second single-felted nip with the center roll through which the first upper fabric passes, and wherein the first upper fabric has a substantially straight run between the first double-felted nip and the second single-felted nip. The press section frame construction includes a front and a rear frame which are not directly connected to each other defining an at least partly open space between them through which most of the press rolls can be replaced, the pick-up suction roll and lower first press roll being mounted on the front frame, the second press roll being mounted on the front frame, and the center roll being supported by a stationary frame part.

Press section and press section/frame construction combination in a

In a paper making machine, transfer apparatus for guiding a paper web from the press section to the drying section includes a smoothing press including upper and lower smoothing press rolls wherein the web is passed from the press section to the smoothing nip either directly or guided by a guide roll. The lower smoothing press roll of the smoothing press is substantially situated at a position which is normally occupied by a so-called baby or lead-in cylinder of a conventional drying section and the drying wire of the drying section is guided over a sector of the lower smoothing roll which is of a size sufficiently large that the web is transferred onto the drying wire which then carries the web as a closed draw onto the first drying cylinder of the drying section and, preferably, to the subsequent drying cylinders as a so-called single-fabric draw.

Transfer arrangement for guiding the paper web from the press section of

A multi-nip press portion or section of a paper or cardboard machine wherein a web is detached from a forming wire by a pick-up roller and transferred onto a first fabric which carries the web into the first nip and wherein the press section includes at least two water-removing press nips which include a common smooth-surface central roller. The central roller has a downwardly facing open sector with which a scraper is associated for passing the web in the case of a break to a pulper or the like. The first nip, which can constitute a press nip and/or a transfer nip is formed by a counter-roller situated in nip-defining relationship with the pick-up roller. A second fabric passes through the first nip over the counter-roller and carries the web on its upper face from the first nip to a second double-fabric nip through which the second fabric, constituting a lower fabric, and a third fabric, constituting an upper fabric pass. The third fabric has a substantially vertical run on which the web is carried from the second nip to a third nip defined by a press roller and the smooth-surfaced central roller. After passing through the third nip, the web separates from the third fabric and follows the surface of the central roller to either a following nip or nips or to a web detachment point.

Multi-nip press portion of a paper or cardboard machine

A press section in a paper machine includes a first double felted press nip defined by first and second rolls through which first upper and second lower felt fabrics pass and at least two single felted press nips defined with a plain surface roll, the first felt fabric passing through a first one of the single felted press nips. The press section includes only non-suction rolls, the first and second rolls defining the first double felted press nip each having a solid shell and recessed surface. The first felt fabric supports the web leaving the wire section and is guided over a first sector of the first recessed surface roll wherein the direction thereof is changed so as to be directed generally upwardly prior to the first double felted press nip. The second lower felt fabric which passes through the first double felted press nip is guided over a second sector of the first recessed surface roll which comprises at least a substantial portion of the first sector thereof to provide external support for the web. The second felt fabric is separated from the web substantially immediately after the first double felted press nip whereupon the first felt fabric and web supported thereby is conducted to and passes through the first single felted press nip, the web then detaching from the first felt fabric and adhering to the surface of the plain surface roll for subsequent passage through the second single felted press nip.

Press section in a paper machine

A paper-manufacturing machine and method include the feature of detaching a web from a forming wire by utilizing a stationary transfer suction box past which a felt travels while contacting the web so that the latter becomes detached from the forming wire and adheres to the felt while travelling with the latter beyond the forming wire. The felt and web are lapped through a substantial angle around a roll having a recessed surface whiletravelling toward the first press nip of a press section, and at this roll around which the felt and web are lapped a means is provided for directing steam toward the web and through the latter and the felt inwardly toward the recessed surface of the guide roll so that the flowing steam will on the one hand heat water carried by the web to enhance dewatering of the web at the first press nip while on the other hand the steam will serve to maintain the web reliably in engagement with the felt as the latter travels toward the first press nip. Beyond the first press nip the web may be subjected to one or more additional press nips and, if desired, to the smoothing action of a smooth-surfaced roll which presses the web against a central smooth-surfaced roll of the press section, before the web is guided away from the central press roll to a drying section.

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Jyvaskyla, Finland

Olli Tapio