Other

Oy Wilh. Schauman Ab

Paavo J Valkama

A method of manufacturing paper, cardboard, or another equivalent fiber web having a certain stretchability and/or a high coefficient of friction includes the steps of shortening or upsetting a paper web just prior to conveying the latter to a press section while adhering the web at the press section to a fabric in the form of a suitable felt or wire which is common to successive press nips of the press section for conveying the web to the successive press nips, these press nips including first and second press nips where the web is engaged by an additional endless fabric structure in the form of suitable felt or wire so that at least at the first and second press nips the web is sandwiched between a pair of fabrics, with this additional fabric structure being spaced from the part of the web which travels from the first to the second press nip. Subsequent to at least one of the first or second press nips the additional fabric which engages the web is dried before returning to its engagement with the web so as to remove therefrom water which has been transferred thereto from the web.

Method of operating a paper machine, particularly a press section thereof

A paper machine has a press section for dewatering a web, this press section including at least three consecutive press nips and a common endless fabric, in the form of a suitable wire or felt, traveling through all three press nips for conveying a web consecutively therethrough. At the first two of the three consecutive press nips there is an additional fabric structure in the form of one or two endless fabrics in the form of suitable wires or felts, which engage the web at the first and second press nips at the side of the web opposite from the common fabric. However, the additional fabric structure is spaced from that part of the web which travels from the first to the second press nip.

Press section of a paper machine

A paper machine press section has an intermediate press nip defined between a pair of press rolls, a web conveying fabric in the form of a suitable felt or wire travelling between these press rolls together with a web carried thereby while engaging one of the press rolls. An endless fabric means in the form of a suitable felt or wire laps the other press roll to travel also through the intermediate press nip while engaging the web at the side thereof which is directed away from the web-conveying fabric. Thus, while travelling through the intermediate press nip, the web is compressed between the above fabrics. Immediately subsequent to the intermediate press nip, the web-conveying fabric together with the web conveyed thereby lap the press roll which engages the web-conveying fabric through an angle which is at least 5.degree. and which preferably is in a range of approximately 7.degree.-30.degree.. The roll which engages the web-conveying fabric is preferably a smooth-surfaced roll, while the other press roll has a recessed water-receiving recess formed, for example, by grooves, blind bores, or the like.

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68610 Leppaluoto, Finland

Paavo J Valkama