| 摘要 |
A headbox of a paper machine which is provided with a dilution profiling system which uses a feedback-connected regulation system to control the cross-direction basis weight profile of the paper web produced by the paper machine. The dilution profiling system includes a feed header for a dilution liquid or for a stock suspension of a consistency lower than the consistency in the headbox, feed ducts fill idly coupled to the dilution header and regulation valves associated with the feed ducts for the dilution liquid, whereby the dilution liquid is passed to an area between a front wall of the inlet header of the headbox and a slice duct of the headbox. In the dilution profiling system, edge feed arrangements are integrated in both lateral areas of the headbox. The edge feed arrangements include ducts by whose means it is possible to pass edge flows from the inlet header of the dilution profiling system into both of the lateral areas of the headbox, which edge flows have velocities and/or mutual velocity ratios that can be set and/or regulated. By means of the edge flows, a controlled transverse velocity component is produced in the stock suspension jet so as to control the cross-direction fiber orientation profile.
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