摘要 |
A forming web for the sheet-forming part of a paper machine consists of a more than one-layered, in particular flat woven fabric made of plastic fibres with longitudinal threads which extend in the travelling direction and cross-threads which extend transversely thereto. One group of cross-threads lies in the plane of the paper side and floats there on longitudinal threads whose number is at least the same as the number of cross- threads on which the longitudinal threads float on the paper side. The plane of the machine side exclusively consists of a second group of cross-threads. In order to improve paper web formation and abrasive properties, the forming screen is characterized by the following features: (a) at least part of the cross-threads (4, 7, 8, 13, 17, 20, 21, 26, 30, 31) have a flattened cross-section; (b) the flattened cross-sections (4, 7, 8, 13, 17, 20, 21, 26, 30, 31) are arranged in such a way that their cross-section is larger in the plane of the fabric than across the plane of the fabric; (c) the ratio between the cross-section in the plane of the fabric and the cross- section across the plane of the fabric lies between 1.2 and 2.2. preferably between 1.2 and 1.8.
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