Abstract: An uncreped tissue sheet having improved softness results from supplementally dewatering a wet web to a consistency of greater than about 30 percent using noncompressive dewatering techniques prior to a differential speed transfer and subsequent throughdrying. An air press particularly well suited for providing the supplemental noncompressive dewatering incorporates side and/or end seals to minimize escape of pressurized fluid. A creped tissue sheet can be produced with a variety of manufacturing benefits using the air press.

Abstract: An apparatus is disclosed for maintaining a fluid seal with a moving substrate. The apparatus includes an enclosure and a cap. The enclosure has a first surface and a second surface with the first surface being in sealing contact with the moving substrate. The cap seals off the second surface of the enclosure. The cap is secured to the enclosure at at least two spaced apart locations and has a non-secured portion that is capable of deflecting independently of the enclosure. The apparatus further includes means for introducing a pressurized fluid into the enclosure. The pressurized fluid creates a net force on the enclosure of zero and a force on the cap which causes a portion of the cap to deflect. The deflection of the cap allows the first surface of the enclosure to remain in sealing contact with the moving substrate.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering.

Abstract: Pressurized web treatment systems include a moving web that passes through a pressurized treatment chamber having a sealing assembly with a leakage control system. Leakage control is achieved by the cooperative effect of localized leak detectors and leak reduction means that applies a local sealing force on the seal assembly responsive to a signal from the leak detectors such that increased sealing occurs in the vicinity of the leak. In particular, an air press for paper web dewatering has improved efficiency by virtue of the leakage control system, which features local leak detectors and local force generation means associated with a flexible seal assembly to reduce leakage at the edges of the stationary plenum of the air press. Local leak detection can be based on sonic measurement with microphones, detection of escaping tracer gas, optical signals, and other means.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering.

Abstract: An uncreped tissue sheet having improved softness results from supplementally dewatering a wet web to a consistency of greater than about 30 percent using noncompressive dewatering techniques prior to a differential speed transfer and subsequent throughdrying. An air press particularly well suited for providing the supplemental noncompressive dewatering incorporates side and/or end seals to minimize escape of pressurized fluid. A creped tissue sheet can be produced with a variety of manufacturing benefits using the air press.

Abstract: A suction breast roll former has a support surface with a plurality of apertures formed therein that are operatively connected to a vacuum source. A headbox has a flexible roof extending downstream from a slice opening and disposed adjacent to a support surface of the suction breast roll. The headbox permits the flexible roof to bend over a range of movement relative to the support surface to match the shape of a drainage curve suiting current operating conditions. A method of forming a paper web includes the steps of supplying an aqueous suspension of papermaking fibers to a forming zone created between the suction breast roll and the headbox. The headbox includes a slice body and an apron that define a slice opening therebetween and also has a flexible roof extending from the slice opening and spaced from the support surface to define a forming zone therebetween. A forming fabric is passed through the forming zone to receive the aqueous suspension of papermaking fibers.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering. The air press has an air plenum and a vacuum collection device, each on opposite sides of two support fabrics that sandwich the paper web. There are cross machine sealing blade(s) that impinge upon the support fabrics and is opposed on the other side of the support fabrics by a sealing member formed of deformable material. The air plenum and vacuum collection device are movable relative to one another so that the sealing blade and deformable sealing member form a seal in the operating position of the air press.

Abstract: A noncompressive dewatering device generates air streams that can be used to remove water from cellulosic webs in an energy efficient manner. Further, a wet-pressed machine can be modified to economically produce low-density tissue with an energy/capital efficiency greater than that of the throughdrying process. For instance, a cellulosic web can be non-compressively dewatered from a post forming consistency to a consistency from about 25 percent to the water retention consistency by passing air through the web with an Energy Efficiency at least 10 percent greater than that achievable using vacuum dewatering at the same speed.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering.

Abstract: A tissue sheet is made using a modified wet pressing process employing an integrally sealed air press. After initial formation and conventional vacuum dewatering, the wet web is conformed to the surface contour of a relatively coarse fabric to give the web a textured surface. By creating a pressure differential across the web of at least 30 inches of mercury and an air stream through the web of at least 500 SCFM/in.sup.2, the air press noncompressively dewaters the wet web to a consistency of about 30 to about 40 percent prior to a Yankee dryer. The web is dried to substantially preserve its three-dimensional, throughdried-like texture. The resulting web has an exceptionally high degree of bulk and absorbency not previously found in wet-pressed products.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering. Side seal members are positioned beyond the lateral edges of the wet web and support fabrics. These seals flex into sealing contact with the opposite sealing contact surfaces upon exposure to the presurized fluid of the air press.