Vacuum control system and method for dewatering fabrics

摘要

A vacuum control system and method for dewatering felts or fabrics on a papermaking machine including a suction pipe and a centrifugal exhauster connected to the suction pipe to supply a variable vacuum level. The fabric is passed over a slot in the suction pipe so that suction applied therethrough will dewater the fabric. A variable drive device is connected to the centrifugal exhauster for its operation with the variable drive device being responsive to an increase in the vacuum level in the suction pipe as fabric permeability decreases to correspondingly increase the speed of the centrifugal exhauster so as to increase the vacuum level in the suction pipe as a function of the decrease in felt permeability.