Abstract: Paper and paperboard which have been thoroughly dried but not calendered is provided with a smooth surface by rewetting a thin layer (5% to 10% of the thickness) along the surface and then pressing the resulting damp surface against a substantial portion of the surface of a heated dryer drum or other smooth-surfaced cylinder. This technique provides the web with a surface comparable in smoothness with what can be obtained by calendering but without the degree of compaction which occurs in calendering, due to the fact that with the major portion of the web dried, it is highly resistant to such compaction. The same method steps can be applied subsequently to the reverse side of the web to provide it with two smooth surfaces. It is also possible to forego the rewetting step if the initial drying of the web is unsymmetrical so that one surface remains wetter than the remaining portion of the web.

Abstract: A pair of enclosed explosion chamber flowboxes are combined so that the top exit slice plate of the first chamber provides the lower exit slice plate of the second chamber downstream of the first chamber so that pressurized furnishes for a two-ply web are laid one on top of the other over a very short distance.

Abstract: A flowbox for a paper or board web-making machine is provided with at least one side wall movable along an axis at right angles to the direction of stock flow through the flowbox, whereby the width of the flowbox may be varied and the web deckled before it leaves the flowbox.

Abstract: A method for producing a self-sustaining sheet of essentially cellulosic fibrous material with improved strength wherein a dry-laid web is moistened and then consolidated by passage along a heated consolidating surface wherein the web is held against this surface by one side of a supporting band, against the other side of which at least two spaced apart pressure rolls exert a pressure acting through the supporting band against the web, which pressure is preferably between 150 and 500 pounds per linear inch. The supporting band thereby maintains the web against the heated consolidating roll between said pair of pressure nips.

Abstract: Apparatus for dry-laying cellulosic fibres on a foraminous travelling band comprises a distribution chamber one wall of which facing the band is provided by a vibratable screen. Within the chamber is a rotating brush roll positioned so that the brushes cause the screen to vibrate. Fibres are urged through the screen partly by the action of the brush roll. Provision may be made for recirculating air which has passed through the band back to the chamber.