| 摘要 |
Forming gap arrangement in a double-screen former of a paper machine to control the thickness profile h of the lip stream. In the arrangement a gap former that includes forming screens functioning opposite each other 11, 13 is applied, between which a web forming zone with a double screen is situated. The forming screens 11, 13 delimit between them a forming gap G which narrows in a wedge- like manner, to which a pulp suspension stream J is fed via the lip channel 14 of the headbox. The thickness profile of the pulp suspension stream J is controlled in the cross direction by profiling the surface 21 of at least one breast roll 10 which is arranged within the forming screen 11 in the region of forming gap G. The thickness profile h of the pulp suspension stream J is controlled by profiling the surface 21 of breast roll 10 which is above and/or beneath the forming gap G, for example, by means of a series 20 of hydraulic loading elements arranged within the surface 21 of breast roll 10. <IMAGE>
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