Suction couch

Fig. 6.3 Schematic of a forming roll and a suction couch roll (source Voith).

In suction formers 3 to 11 cylinder formers in series with suction chambers produce webs of about 25 to 100 g m each which are couched on a transfer felt, thus building up the baseboard. The maximum speed is about 350 m min , the maximum width is about 5 m. Cylinder formers without vacuum appHcation are limited to a maximum speed of about 150 m min ... 

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