MULTI-LAYER WEB FORMATION SECTION

摘要

Multi-layer web formation section having at least two successive wire units (300, 310), which have one wire (11) in common. A first headbox (100) supplies fibre pulp to the forward end of the first wire unit (300) and a second headbox (110) supplies a new fibre pulp layer to the forward end of the second wire unit (310) atop a first partial web (W1) formed in the first wire unit (300). In the forward end of a two-wire stretch of the second wire unit (310) there is a first non-pulsating dewatering zone (Z1b), which comprises at least one first formation shoe (200b), which has a curved cap (201) placed on the side of the new fibre pulp layer and provided with openings (202) extending through the cap (201), and an under-pressure (P) affecting through the cap's (201) openings (202). A two-wire stretch of the second wire unit (310) has a second pulsating dewatering zone (Z2b), which is formed by fixed dewatering lists (210b), between which there are gaps (220b) and an under-pressure (Pb) affecting in these.