Abstract: A process and apparatus for treating a pulp web (9) in a paper or board machine in a pressing unit (29) with one press roll (24) that has a rotating press shell (25) and one opposing roll (23), where the pulp web (9) is dewatered in an extended press nip (26) between the opposing roll (23) and the pressing shell (25) of the press roll (24). The pulp web (9) is carried on the rotating pressing shell (25) of the press roll (24) to a transfer zone (30), where the pulp web (9) is passed from the pressing shell (25) onto a transfer element (31, 27) after leaving the extended press nip (26).

Abstract: A process and apparatus for treating a pulp web (9) in a paper or board machine in a pressing unit (29) with one press roll (24) that has a rotating press shell (25) and one opposing roll (23), where the pulp web (9) is dewatered in an extended press nip (26) between the opposing roll (23) and the pressing shell (25) of the press roll (24). The pulp web (9) is carried on the rotating pressing shell (25) of the press roll (24) to a transfer zone (30), where the pulp web (9) is passed from the pressing shell (25) onto a transfer element (31, 27) after leaving the extended press nip (26).

Abstract: A pressurized box is positioned opposite a vacuum box. The pressurized box has a leading cross machine direction baffle with a ceramic shoe which engages a forming fabric, and a trailing cross machine direction baffle of similar construction. Two end deckles complete the pressurized box. The leading cross machine direction baffle presses against a resilient seal which causes a web contained between upper and lower forming fabrics to wrap about the baffle shoe a few degrees forming an effective end seal which does not allow air to bypass the baffle. The trailing cross machine direction baffle is positioned over a vacuum box which prevents air from leaking around the trailing baffle. A vacuum box draws air through the forming fabrics and the web, from the pressurized box increasing the total pressure gradient across the web to 20 to 30 psi or more. The pressure box and opposed vacuum box form an air press. The pressure box is positioned and held against the forming fabrics by opposing air tubes.

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: An Extended Nip-type press has a blanket which passes over a shoe which is urged against a backing roll to form a press nip. A hydraulic system and controller provides for automatic continuous oscillation of the blanket in the cross machine direction. The oscillation results in a region of high fatigue continuously moving over the blanket surface so that the amount of time any particular region sees wear is minimized. Positioning of the heads to which the blanket ends are mounted is controlled by hydraulic pistons mounted between a support beam and the heads. A controller operates a valve to reverse the direction of motion of the blanket when sensors indicate one end of the blanket has reached a stop. A throttle valve controls the rate at which hydraulic fluid is supplied to the cylinders which urge the head away from the shoe.

Abstract: An extended nip press apparatus is disclosed for removing water from a web. The apparatus includes a rotatable backing roll and an elongate shoe which cooperate with the backing roll for defining therebetween an extended nip for the passage therethrough of the web. The shoe defines a concave surface. A bearing blanket is movably disposed between the backing roll and the concave surface. The arrangement is such that the web is supported by the blanket with the web being disposed between the blanket and the backing roll. A lubricant is supplied between the concave surface and the blanket such that the blanket is slidingly supported by the concave surface during passage of the blanket through the extended nip. The concave surface encompasses a pocket defined by the shoe.

Abstract: An extended nip press apparatus is disclosed for pressing water from a web of paper. The press includes a blanket which defines an endless loop and a first and a second lateral edge. Edge seals cooperate with the edges for sealing the edges of the blanket against egress of lubricant disposed between the shoe and the blanket. The edge seals include a head rotatably secured to a frame and an extension which extends from the head. The extension cooperates with the first edge of the blanket and defines a duck's bill configuration in a cross-machine sectional view such that the first edge of the blanket conforms to a surface defined by the extension. The surface has a first portion which undulates radially away from the head in an outward direction, and a second portion which undulates radially inwardly towards the head in an outward direction. A clamp adjustably secures the first edge of the blanket to the extension so that flow of lubricant from between the shoe and the blanket past the head is inhibited.

Abstract: A bearing blanket is disclosed for an extended nip press of a papermaking machine. The blanket (44) includes a base (46) having a first and a second side (48, 50). A first laminate (52) extends along the first side (48) of the base (46), the first laminate (52) having an interface (54) which is disposed contiguous with the first side (48) of the base (46) and a face (56) which cooperates with a hydraulically loaded shoe (22) of the extended nip press (12). A second laminate (58) extends along the second side (50) of the base (46) with the second laminate (58) having a surface (60) which is disposed contiguous with the second side (50) of the base (46). The second laminate (58) defines a plurality of recesses (64, 66) for relieving fluid pressure during passage through the nip. The first laminate has a hardness which permits flexing of the first laminate while the second laminate has a hardness such that crushing of the recesses during passage through the extended nip is inhibited.

Abstract: An enclosed extended nip press apparatus is disclosed for pressing water from a formed web. The apparatus includes a frame and a backing roll rotatably secured to the frame. A press member cooperates with a backing roll for defining therebetween an extended nip for the passage therethrough of the formed web. A press blanket extends in a closed loop through the nip, the blanket having a first and a second lateral edge and an inner and an outer surface. A first and a second head are rotatably secured to the press member with the first and second heads being disposed adjacent to and cooperating with the first and the second edges respectively of the blanket. The first and the second heads define first and second annular channels respectively for the reception therein of the first and the second lateral edges respectively of the blanket. A first and a second annular seal are disposed within respectively the first and the second channels with the seals contacting the respective edges of the blanket.

Abstract: A bearing blanket is disclosed for an extended nip press of a papermaking machine. The blanket (44) includes a base (46) having a first and a second side (48, 50). A first laminate (52) extends along the first side (48of the base (46), the first laminate (52) having an interface (54) which is disposed contiguous with the first side (48) of the base (46) and a face (56) which cooperates with a hydraulically loaded shoe (22) of the extended nip press (12). A second laminate (58) extends along the second side (50) of the base (46) with the second laminate (58) having a surface (60) which is disposed contiguous with the second side (50) of the base (46). The second laminate (58) defines a plurality of recesses (64, 66) for relieving fluid pressure during passage through the nip. The first laminate has a hardness which permits flexing of the first laminate while the second laminate has a hardness such that crushing of the recesses during passage through the extended nip is inhibited.

Abstract: An extended nip press has a looped belt mounted over a shoe having a concave surface which presses the belt against a mating surface on a roll to provide an extended nip. The shoe has a support which is movable in a skewing sense relative to the longitudinal axis of the roll. Lateral movement of the belt is monitored. When it has moved beyond predetermined limits in either direction, the shoe is skewed to alter the frictional forces on the belt as it passes over the shoe's surface. This controls the position of the belt and keeps it centered in the nip.

Abstract: A guiding apparatus is disclosed for guiding an extended nip press blanket relative to a pressing shoe. The apparatus includes a nose member which is pivotally-connected to the shoe for guiding the blanket relative to the shoe. An actuator is secured to the shoe for pivoting the nose member relative to the shoe. A connector extends between the actuator and the nose member for connecting the actuator to the nose member such that when the actuator is actuated, the nose member is skewed relative to the shoe so that the blanket is guided laterally relative to the shoe as the blanket moves over, and in contact with, the nose member.