BLOW AND AIR-CONDITIONING DEVICE FOR AN INVERTED CYLINDER GROUP IN THE DRYING SECTION OF A PAPER MACHINE

摘要

The invention is related to a blow and air-conditioning device for an inverted cylinder group in a drying section of a paper machine. The inverted cylinder group includes a lower row of drying cylinders and a corresponding row of leading cylinders or rolls placed above said cylinders in the gaps between them. The inverted cylinder group is provided with single-wire draw so that the heated drying cylinders placed in the lower row in the group, are placed outside the loop of a drying wire and the lead cylinders in the group are placed inside the drying-wire loop. A blow box is fitted in spaces between adjacent leading cylinders and above the drying cylinders. A nozzle of the blow box directs blowings into a wedge-shaped nip space opening in the direction of running of the web, which outlet nip space is defined between the face of the drying cylinder and the run of the web and of the drying wire. The blow box further includes nozzle slots or perforations which direct a set of jets at the web running over the leading cylinders in order to promote evaporation of water out of the web.