Paper-making press station - has a mechanism at pressure chamber of pressure shoe to compensate for abrupt pressure peaks

摘要

The press unit of a papermaking machine, where a pressure gap is formed with a counter roller through a rotating mantle or strip in a ring, has a press shoe at a carrier in a pressure chamber contg. a pressure medium. The pressure chamber has a system to compensate for abrupt pressure peaks. The pressure compensation system pref. has at least one pliable zone in the walls of the pressure chamber against the pressure medium, formed by compressible units or the carrier body. A safety valve can be between the pressure chamber wall and the interior of the press mantle. The pliable zone can also be at the press shoe, with at least one flexible section between the shoe cover and shoe piston as an intermediate layer or zone. The elastic sections can also be at the shoe cover and piston, with a pliable area of the shoe cover with at least one chamber - alone or divided into a number of sub-chambers over the working width across the line of paper web travel. The chamber has elastic walls and is subjected to internal pressure. USE/ADVANTAGE - The assembly is used at the press station of a papermaking machine, where the pressure is applied by a shoe bearing against a ring formed by a mantle or belt against a counter roller or the like, with the paper web passing through the gap between them. The system prevents damage and dry running, through irregularities in the paper and the like, which give abrupt pressure peaks within the pressure shoe assembly.