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TWIN WIRE FORMERS
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ADVANTAGES
- High flexibility of use for all types of paper or board grades to be produced.
- In order to meet the physico-mechanical characteristics of the sheet, the VACUALL is located on the Fourdrinier :
- either as a TOP-FORMER (VACUALL of type IV).
The distance is between 8 m and 9 m from the headbox.
- or as a FORMER (VACUALL of type V).
The distance is between 1,5 m and 3 m from the headbox.
- Better formation as far as the sheet look-through is concerned.
- Controling sheet fiber orientation.
- Better sheet symmetry or orientation.
- High distribution of the fines.
- Better ash distribution.
- Increase of the Fourdrinier drainage capability.
- Increase of the sheet dryness at the Fourdrinier outlet.
- Decrease of the vacuum power on the bottom Fourdrinier.
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VACUALL type IV / Writing-Printing paper machine
Width 4200 mm - Speed 800 m/mn
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VACUALL type IV in Top Former position
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Design of the draining/forming elements of Former Vacuall type V
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Design of lead-in box
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Design vacuum inversed box
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Typical samples show the difference between formation on a conventional Fourdrinier vs. formation after the installation of a VACUALL
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