摘要 |
A paper machine multiple cylinder dryer includes a plurality of drying cylinders, in conjunction with which a drying fabric supports the web as it moves from one cylinder to another in closed conduction. A supporting fabric supports the web on some of the cylinders. The runs of the web supported by the drying fabric, the free surfaces of the drying cylinders and the runs of the supporting fabric confine elongated pockets in conjunction with the cylinders. In order to prevent web breaks occurring in the drying section of the fast-running paper machine, since such breaks are among the most important factors limiting the increasing of paper machine speeds, the multiple cylinder dryer provides a pressure greater than the ambient atmosphere pressure in the pockets in the direction of travel of the web, at least in the initial part of the dryer. This results in the considerable stabilization of the running of the web. One manner of producing the over-pressure is to partially or totally close both ends of the pockets with particular closing plates. |