摘要 |
A method and apparatus for lateral alignment of a crossdirection profile control of a web as required in a paper-making process. In the method, a certain cross-direction profile of a dried web, particularly the basis weight profile thereof, to be aligned is gauged. A profile measurement signal thus obtained is passed to a control system of the paper machine which provides a control signal suited to control adjustment devices of the crossdirection profile control provision. The web is provided with at least one marker line whose lateral shift or shifts is/are detected at the measurement point of the cross-direction profile of the dried web, or in the vicinity thereof. The detection of the lateral shift(s) is used to generate a measurement signal thereof which is employed to control the lateral alignment of the web profile adjustment provision. The information obtained from the detected lateral shift(s) then used in the control of the lateral alignment of the consistency profile control provision adapted in conjunction with the paper machine headbox. The marker agent used to make the marker line is injected to the stock at the inlet side of the stock feed channel to the paper machine headbox, most advantageously close to the control valve set of the consistency profile control provision.
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