Head box for fibrous material web e.g. cardboard web, producing machine, has stock flow nozzle designed in symmetric manner, and upper and lower orifices positionably arranged at outlet-sides of nozzle walls

摘要

The head box (1) has a stock flow nozzle (3) designed in a symmetric manner. Upper and lower orifices (8, 9) are positionably arranged at outlet-sides of upper and lower nozzle walls (4,5). An orifice gap (6) is formed by orifice flow surfaces (SF.8 SF.9) of the lower and upper orifices and has a light clearance (s). Orifice flow lengths (SL.8, SL.9) of the orifice flow surfaces are selected to be equal such that the lower orifice forms a lower lip (10) with a lower lip managing unit (L.10) in a range of 0 to 32 millimeters based on the light clearance.