Twin-wire section

摘要

Twin-wire section for a paper or cardboard machine, having an essentially horizontally extending lower wire (2) onto which an upper wire (5) is placed. The two wires (2) and (5) form with one another a twin-wire zone, in which they jointly first loop round part of the circumference of a forming cylinder (7), specifically starting approximately from its lower vertex line over a looping angle of approximately 45 DEG . The two wires (2) and (5) thereafter loop round part of the circumference of a supporting cylinder (10) arranged in the lower wire (2). The forming cylinder (7) has a storage volume on its circumference. In the looping region, screening water penetrates into the storage volume and is thrown out again (arrows 23) behind the run-off point (98) of the two wires (2) and (5). The screening water is intercepted by a trough (110) and discharged laterally from the upper wire (5). The trough (110) has an upper covering wall (111) with a front edge (112) which extends along the casing of the forming cylinder (7) in the vicinity of the run-off point (98). As seen from inside the trough, the covering wall (111) is concavely curved and is matched to the throw parabola of the screening-water jet (23). <IMAGE>