Paper-making machine drying section - has automatic leader guide system also at the start of twin-blanket drying group

摘要

The end section of a web drying assembly, in a paper-making machine, is a twin-blanket section with an automatic leader guide (77,78) without cables. Pref., the drying section has cylinders of the single blanket group(s) where the web contact surface form 60-85% of the whole drying section for newsprint, 5-80% for SC paper, 40-75% for fine papers and 5-20% for cardboard, to give newsprint with 55-85% dry content, and dry contents of 50-70% for SC paper, fine paper and cardboard. The leader guide (77,78) has a blowing system to carry the leading end from cylinder (74) to cylinder (74'), with the wall of at least one component, such as a scraper carrier (77), parallel to the free web path to deliver an air stream in the line of web travel. At the end of the single-blanket section (23), part of the leader guide (79) can be disconnected so that the incoming leader (9A) temporarily leaves the web path, working with units (79,80) to cut and advance the leader. USE/ADVANTAGE - The assembly is for drying a paper web, in paper-making, where edge strips are cut as leaders to feed through the sections on start-up. The assembly gives a consistent paper quality on both sides, without risk of web fracture even with a high final dry content of around 98% as longitudinal tensions ar broken down, with a conventional point cutter and no cable guides, and without blanket wear.