Metso Paper Inc.

Kari Räisänen

Antti Poikolainen

A multi-layer web formation section has two successive wire units () with a common wire (). A first headbox () supplies fiber pulp to the first wire unit () forming a first partial web (W). A second headbox () supplies a new fiber pulp layer to the forward end of the second wire unit () atop the first partial web. A first non-pulsating dewatering zone (Z) in the forward end of a two-wire stretch of the second wire unit () has a first formation shoe () with a curved cap () placed on the side of the new layer having openings () extending through the cap () with an under-pressure (P) affecting therethrough. A two-wire stretch of the second wire unit () has a second pulsating dewatering zone (Z) formed by fixed dewatering lists (), between which there are gaps () and an under-pressure (Pb) affecting in these.

Multi-layer web formation section

A multi-layer web formation section has at least two successive wire units (). First and second headboxes () supply pulp suspension jets to the forward end of the first wire unit () and the second wire unit respectively to form a first partial web (W) and a second partial web (W) which are joined at a joint (N) between the second wire unit () and a bottom wire (). A first non-pulsating dewatering zone (Z) in the forward end of a two-wire stretch of the second wire unit () is formed by a fixed formation shoe () having a curved cap () placed against one side, having openings with an under-pressure applied. A two-wire stretch of the second wire unit () has a second pulsating dewatering zone (Z), formed by fixed dewatering lists () in the cross machine direction with gaps () therebetween with an under-pressure (Pb) applied.

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Muurame, Finland

Kari Räisänen