Continuous fourdrinier cleaner preventing build=up of dirt - has set-back step at the second support bar where the paper web is detached

摘要

In the cleaning system for the continuous fourdrinier of a papermaking machine, where the fourdrinier passes over a bar to a take-up bar with a blower slit between them ,the take-up bar is fitted with a set-back step at the point where the fourdrinier (1) leaves its surfaces. The fourdrinier guide surfaces of both bars have about the same width, while the whole width of the first bar is 1.2-3.0 times the whole width of the second bar. The carrier body which supports both bars pivots on an axis parallel to the blowing slit to vary the angle between the fourdrinier and the first bar and/or the support is moved to and away from the fourdrinier. The water spray assembly is formed by two chambers, parallel to each other across the direction of fourdrinier travel, with a distribution chamber and a jet chamber. The distribution chamber, with a water feed connection, is linked to the jet chamber by a number of channels across the fourdrinier width, and the second chamber has at least one water jet opening. The water jet chamber is directly in front of the first bar with a constant delivery of water to the fourdrinier guide surface of the first bar. ADVANTAGE - The system prevents the build-up of dirt at the cleaner, and requires water of a lower pressure with equal distribution over the fourdrinier width. The cleaner functions effectively at different fourdrinier speeds, and can be located where the paper web is separated from the fourdrinie