| 摘要 |
Web of paper is formed in a space enclosed between an upper flexible lip extending from the straight edge nozzle of a slurry feed box, and a part of the woven metal gauze which is not supported, at least at the end of the forming of the web, in a fourdrinier machine. At the same time, the extraction of the water from the slurry takes place under the action of a vacuum. The vacuum is maintained unaltered after the formation, whilst the web of paper remains on the unsupported section of the gauze. Used to eliminate as far as possible, in a fourdrinier machine, the incorrect laying down of the web of fibres due to excessive turbulence above, or to upwards pressure on the gauze from below. The technique deadens the hydrodynamic disturbances and makes it possible to maintain uniform solidity and superficial weight. A greater amt. of water can be extracted, so that the metal gauze section can be shortened in length. |
