Paper/cardboard web press section has a dividing point after the roller press gap where the blankets flanking the web are separated to follow structured paths for the web to be picked up for the next station

摘要

The press section at a machine for the prodn. of web materials, from a fiber pulp, has at least two press rollers (11,12) where the web (1) is carried through between two blankets (2,3) to take up the extracted water. After passing between the press rollers, the web (1) and both blankets (2,3) travel on a common path (4) to a dividing point (6) where the blankets (2,3) are separated from the web (1). After the dividing point (6), the lower blanket (3) moves around the separating roller (5) with the web (1) by an angle (8) of at least 45 deg . The dwell time of the web (1) at the dividing point (6) is -15 ms. After separation from the web at the dividing point (6), the upper blanket (2) is led to a deflecting guide roller (9) in an unsupported path length of = 80 mm between the separating roller (5) and the deflection roller (9). The web (1), together with the lower blanket (3), travels to a pick-up roller (10) with an air-permeable pick-up belt (7) around it, to be transferred to the pick-up belt (7) and separated from the blanket (3). The clear gap between the separating roller (5) and the pick-up roller (10) is = 80 mm. At least the lower blanket and pref. both blankets (2,3) are press blanket belts. The pick-up belt (7) is a press blanket from the following roller press gap station. The pick-up belt (7) can also be a transfer belt, or it can form part of a drying blanket for a following drying group to dry the web (1). The roller press gap of the press section has an extended structure.