Mini-Encyclopedia of Papermaking Wet-End Chemistry
Part Three: Equipment & Unit Operations

Gap Former

In a twin-wire paper forming machine or "gap-former" the jet of furnish from the headbox is directed into the narrowing gap between two forming fabrics. Water is removed in both directions. The rate of water removal may be enhanced by passing the pair of forming fabrics around a roll, over blades, or over vacuum elements. The bi-directional removal of water tends to produce a sheet in which the fines content and appearance of the two sides is very similar. Because the sheet becomes "set" very rapidly within a gap former, the uniformity of furnish emerging from the headbox can be critical.

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This page is maintained by Martin hubbe, Associate Professor of Wood and Paper Science, NC State University, .