| 摘要 |
The invention concerns a headbox of a paper machine which is provided with a dilution profiling system, by whose means, by making use of a feedback-connected regulation system (40,100,FBS), the cross-direction basis weight profile of the paper web is controlled. The dilution profiling system comprises a feed header (12) for a dilution liquid or for a stock suspension of a consistency lower than the consistency in the headbox, out of which header feed ducts, which are provided with regulation valves (351... 35N), for dilution liquid are passed to the area between the front wall (11a) of the inlet header (11) of the headbox and the slice duct (17) of the headbox. In the dilution profiling system, edge feed arrangements have been integrated, which have been fitted in both of the lateral areas of the headbox. The edge feed arrangements comprise ducts by whose means it is possible to pass edge flows (Fa,Fb) from the inlet header (12) 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 said edge flows (Fa,Fb) a controlled transverse velocity component is produced in the stock suspension jet (J) so as to control the cross-direction fibre orientation profile. <IMAGE>
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