| 摘要 |
A method is disclosed far forming a paper web having a law tensile ratio. The method includes the steps of ejecting stock (S) substantially horizontally from a headbox (12), and receiving the rejected stock (S) onto a substantially horizontally disposed looped first wire (14), moving at substantially the same speed and the same direction as the ejected stock (S), The arrangement is such that a first portion of water (18) is removed from the elected stock (S) downwardly through the first wire (14) daring passage of the ejected stock (S) through an initial dewatering zone (20). The partially dewatered stock is sandwiched between the first wire (14} and a looped second wire (22), the wines (14, 22) defining therebetween a secondary dewatering zone (24) for further dewatering the ejected stock. A second and third portion of water (28, 30) are removed downwardly and upwardly, respectively, through the first and second wires (14; 22) during movement of the ejected stock past a curved shoe (26). The curvature of the secondary dewatering zone (24) is reversed such that the wires (14, 22) extend around a curved inverted box (34) connected to a source of partial vacuum (36), so that a fourth, portion of water (38) is removed upwardly through the second wire (22) into the curved box (34). The arrangement is such that a gradual dewatering of the ejected stack is accomplished during passage of the stock (S) through the initial and secondary dewatering zones (20, 24), thereby inhibiting removal of lines from the ejected stock and minimizing the tensile ratio of the resultant web (W).
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