Piston apparatus for use in web pressing components in papermaking machinery

摘要

A piston apparatus for use in a controlled deflection roll includes a rectilinear-shaped piston having at least one side seal extending longitudinally in a slot in each side wall and an end seal in each end of the piston extending between the side seals. The end seals have at least one pair of intersecting surfaces at each end thereof which cooperate with a corresponding pair of surfaces of each side seal to move longitudinally relative to the piston and side seals to maintain a continuous seal peripherally about the piston. The continuous seal engages the side walls of a channel within the support shaft of the controlled deflection roll and a non-movable seal surface in each of two, opposed dams at either end of the channel in the support shaft. The side and end seals move with the piston relative to the support shaft and seal surfaces on the end dams.