US Patent 7416636 Method and apparatus for foam forming

The present invention relates to a method and apparatus for foam forming, wherein fibrous foam suspension is introduced from the head box (78, 178) of a production machine to the web forming section thereof. At least one solid material is mixed into the foam in the head box (78, 178). The method and the apparatus of the invention are particularly suitable for manufacturing various web-like products of cellulose, glass fiber, aramide, sisal, or other corresponding fibre material.