Paper mill dewatering press drum is separated from adjacent water collection trough by diverging vacuum gap

摘要

A paper mill has a web dewatering press with a suction press drum (10) operating in conjunction with a woven press belt (13). Water is expelled to a collection trough (15) and discharge duct (18). The trough has a concave guide surface (19) extending over and along part of the drum outer face, from which it is separated by a gap 10-25 mm wide. The gap increases in the direction of rotation. The water collection trough extends from the inlet gap to the outlet gap and is position-adjustable with respect to the drum. The trough can be shifted between a maintenance position and an operating position. The combined action of the rotating drum and widening gap generates a partial vacuum over the drum surface.