FI883922A - HYBRIDFORMARE I EN PAPPERSMASKIN. - Google Patents

Abstract

Hybrid former in a paper machine, which includes a first wire loop 2, 40 that cooperates with the headbox 1 of the paper machine in which the beginning A of the wire loop forms a first drainage zone with a single wire, in the area of which the pulp suspension flowing from headbox 1 is drained by means of drainage device 4, 5 in front of the first wire loop 2, 40 downward through wire 2, 40. The former includes a second wire loop 3, 54 which is arranged above the first wire loop 2, 40 so that the wires 2, 30; 40, 54 together form a second drainage zone with a double wire that immediately follows the first drainage zone. The former includes a drainage device 8, 9, 45 with at least partially bent surfaces arranged in front of the first wire loop 2, 40 and in the first part of the second drainage zone with the double wire, in which the center of bending of the draining device is on the side of the first wire loop 2,40 and controls the common trend of the first and second wire loops in the first part of the second drainage zone with the double wire. In the region of the second drainage zone with the double wire, inside of the second wire loop 3, 40 and essentially at said drainage device 8, 9, 45 with the bent surface, at least one device that prevents drainage through the second wire 3, 40 is positioned at a given distance from the inner surface of the second wire loop 3, 54 by means of damming pressure and which suitably also has a controlling function and extends over the entire working width of the former. <IMAGE>