Valmet Oy

Lassi Veijonen

Oiva Vallius

Olli Tapio

Eero Hannonen

A method is employed in a press section of a paper machine for changing a pick-up and/or press fabric, the substantial run of which when the fabric is in its normal operating position, passes above a group of nip defining press rollers. Insert members of the machine frame are removed to define gaps therewithin and the press nip or nips through which the fabric passes are open. In the method, upper guide rollers situated within and guiding the loop of the fabric are shifted from an upper operating position occupied thereby when the fabric is in its normal operating position to a lower position and the fabric to be changed is transported with the same being wound in double manner on a changing pole. The fabric is opened and spread out to define a loop which encircles all of the press and guide rollers which will be situated within the fabric loop when the fabric is in its normal operating position. The loop so formed and transported is passed into the machine frame through the gaps defined therein by the removal of the insert members therefrom and into the open press nips. The fabric situated within the machine frame is spread out from the changing pole while the upper guide rollers are shifted from the lower position back to their upper operating position, whereupon the insert members are replaced in the machine frame and the opened press nips are closed.

Method and apparatus for changing a pick-up fabric and/or press fabric

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

Lassi Veijonen