| 摘要 |
A method and apparatus for obtaining a desired nip pressure distribution profile in the cross direction of a paper web. The paper web passes through a nip, the latter defined by at least one elastomer covered roll, the covered roll having polarizable particles or magnetic particles embedded therein. A plurality of spaced plates or spaced coils each generate a local field (respectively electric or magnetic) which acts upon individual spaced zones or regions along the covered roll. The field may thus be an electric field or a magnetic filed. The affect of the field is to change the effective modulus of the elastomer by acting on the particles. In turn, this action varies the nip pressure pulse as to exert a desired pressure at each of a plurality of spaced zones or regions on the paper web, to thus create or process a more uniform product in the nip. The method and apparatus can be used, for example, to improve web moisture profiles in the press section of paper machines.
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