Abstract: An applicator device (1) applies surface size to at least one side of a web (W). A pressure effect is applied to the web (W) by subjecting the web (W) to an underpressure and/or to an overpressure such that surface size is forced to penetrate into the pores of the web. Most advantageously, an underpressure is created that sucks applied surface size from the surface of the web (W) into the pores in the inner layers. Surface size is applied to a web first side (W1) and a vacuum effect is applied to the web's opposite side (W2) to cause air to flow through the web (W) such that surface size moves from the first side (W1) in the direction of the second side (W2) into the web (W). Correspondingly, both sides of the web (W) can be treated in successive stages.

Abstract: A grooved forming roll in a paper machine has a rotably supported shell (20) with circular openings (21) arranged to be open at least on the outer surface of the shell (20). Each opening (21) has a circular groove which is formed on the outer surface and which is arranged concentrically relative to the opening (21). A portion of the formed circular openings (22) extends to each opening (21) from each adjacent opening (21). The outer radius (r) of the circular groove (22) is arranged such that the number of necks (24), delimited by the adjacent openings (21) and their circular grooves (22) on the shell outer surface within the area of one circular groove (22), is greater than the number of the adjacent openings (21) of the corresponding opening (21).

Abstract: A sealing strip of a suction roll (4) for a material web machine includes a longitudinal strip element (3) and a longitudinal holder (2) shaped as a U profile open in the direction of a facing surface (41). An element first layer (31) is an easily adjusting material and a second layer (34) is a stiffer material in the loading direction than the first layer. The strip element may be loaded so it or its edge does not substantially bend in the direction of movement of the facing surface. To optionally reduce the effect of abrasion: an inner mantel surface is treated by grain blasting, thermal injection coating, chemical or electro-chemical precipitation coating and/or polymer-based coating; and/or a lubricant or additive is fed between surfaces abrading against each other; and/or at least part of suction holes in a wall of the mantel are broached (71).

Abstract: An arrangement in connection with the press and dryer section of a web-forming machine includes first and second devices for transporting the web. The second device includes a dryer wire and a roll arranged to support it. In the arrangement there is an open gap between the first and second devices, across which the web is arranged to be transferred, so that the web and the dryer wire form a closing throat. The arrangement further includes a deflector before the open gap in the direction of travel of the dryer wire, which is arranged close to the dryer wire, in order to restrict the air layer travelling with the dryer wire, and thus to prevent the formation of an excess pressure in the closing throat.

Abstract: The operation of a doctor assembly (16) in a paper machine is monitored. In case of a malfunction, the paper machine's (10) control devices (14-14?, 15) are used to carry out the necessary measures for eliminating the malfunction and carrying out repair and/or protective measures. In addition, detector devices (20) are arranged in connection with the doctor assembly (16), to detect a malfunction. The detector devices (20) are connected to the control devices (14, 14?, 15) of the paper machine (10), in order to carry out the said measures automatically. The invention also relates to doctor assemblies in a paper machine for implementing the method.

Abstract: A doctor unit in a paper machine includes a blade carrier having a blade holder fitted to the blade carrier. A doctor blade is mountable in the blade holder to doctor a roll or similar moving surface. The blade holder and/or doctor blade include one or more sensors installed inside the construction or on its surface. The sensors are arranged to measure the wear of and/or stress in the blade holder and/or doctor blade.

Abstract: An applicator device (1) applies surface size to at least one side of a web (W). A pressure effect is applied to the web (W) by subjecting the web (W) to an underpressure and/or to an overpressure such that surface size is forced to penetrate into the pores of the web. Most advantageously, an underpressure is created that sucks applied surface size from the surface of the web (W) into the pores in the inner layers. Surface size is applied to a web first side (W1) and a vacuum effect is applied to the web's opposite side (W2) to cause air to flow through the web (W) such that surface size moves from the first side (W1) in the direction of the second side (W2) into the web (W). Correspondingly, both sides of the web (W) can be treated in successive stages.

Abstract: An arrangement for doctoring a belt or a soft roll surfacing in a paper or board machine includes a doctor set in connection with a surface with a doctor blade fitted in it for doctoring the surface. The doctor blade is at least partly of a material, the hardness of which is essentially equal to or less than the hardness of the material of the surface, in order to prevent the doctor blade from cutting into the surface. The material is arranged to form a layer extending over the entire width of the doctor blade, and the thickness of which throughout is at least half of the thickness of the doctor blade. A support construction is arranged in the doctor blade, which together with the layer is arranged to form the doctor blade.

Abstract: A caring doctor blade for a paper/board machine having layers of fiberglass and carbon fibers, and a caring layer as a rigid laminated structure, where the caring layer has carbon fibers and grinding particles in direct proximity to the carbon fibers. The orientation of the fiberglass layers is parallel to the longitudinal axis of the blade. At least some of the layers that contain carbon fibers. The orientation of the carbon fibers is substantially diverging from the direction of the longitudinal axis of the blade. A method for manufacturing the doctor blade for a paper/board machine by a pultrusion method is also disclosed.

Abstract: A grooved forming roll in a paper machine has a rotably supported shell (20) with circular openings (21) arranged to be open at least on the outer surface of the shell (20). Each opening (21) has a circular groove is formed on the outer surface arranged concentrically relative to the opening (21). A portion of the formed circular openings (22) extends to each opening (21) from each adjacent opening (21). The outer radius (r) of the circular groove (22) is arranged such that the number of necks (24), delimited by the adjacent openings (21) and their circular grooves (22) on the shell outer surface within the area of one circular groove (22), is greater than the number of the adjacent openings (21) of the corresponding opening (21).

Abstract: The invention concerns an equipment and a method in the transfer of a paper/board web in a paper or board machine. In an embodiment of the invention, the dryer section comprises at least one group of drying cylinders in which, instead of a conventional wire draw, a transfer belt (H100) is employed, to which the web (W) is affixed by effect of adhesion and which transfer belt is passed over drying cylinders (K1, K2, . . . ) and reversing rolls (E1, E2, . . . ) and further in said group (RI) of drying cylinders in the dryer section. The invention also concerns a method in the transfer of the web (W) in the dryer section (K) of a paper/board machine.

Abstract: The invention relates to a method for monitoring the operation of a doctor assembly in a paper machine. In the method, the operation of the doctor assembly (16) is monitored. In case of a malfunction, the paper machine's (10) control devices (14-14′, 15) are used to carry out the necessary measures for eliminating the malfunction and carrying out repair and/or protective measures. In addition, detector devices (20) are arranged in connection with the doctor assembly (16), to detect a malfunction. The detector devices (20) are connected to the control devices (14-14′, 15) of the paper machine (10), in order to carry out the said measures automatically. The invention also relates to doctor assemblies in a paper machine for implementing the method.

Abstract: The invention concerns a method and a device for changing the natural frequency of a nip roll construction in a paper or board machine so that the rigidity of one or several loading elements, for example loading cylinder or loading beam, in the nip roll construction is varied. The loading cylinder with adjustable rigidity in accordance with the invention comprises a cylinder (11), into which two pistons (12, 13) have been fitted. The pistons (12, 13) have been attached each of them to a piston rod (14, 15) of its own, which piston rods have been passed through the end walls (11a, 11b) of the cylinder (11). Thus, in the cylinder (11), between the pistons (12, 13), a work pressure space (16) is formed, and at the opposite sides of the pistons (12, 13) counter-pressure spaces (18, 20) are formed.

Abstract: An arrangement for doctoring a belt or a soft roll surfacing in a paper or board machine includes a doctor set in connection with a surface with a doctor blade fitted in it for doctoring the surface. The doctor blade is at least partly of a material, the hardness of which is essentially equal to or less than the hardness of the material of the surface, in order to prevent the doctor blade from cutting into the surface. The material is arranged to form a layer extending over the entire width of the doctor blade, and the thickness of which throughout is at least half of the thickness of the doctor blade. A support construction is arranged in the doctor blade, which together with the layer is arranged to form the doctor blade.

Abstract: A caring doctor blade for a paper/board machine having layers of fiberglass and carbon fibers, and a caring layer as a rigid laminated structure, where the caring layer has carbon fibers and grinding particles in direct proximity to the carbon fibers. The orientation of the fiberglass layers is parallel to the longitudinal axis of the blade. At least some of the layers that contain carbon fibers. The orientation of the carbon fibers is substantially diverging from the direction of the longitudinal axis of the blade. A method for manufacturing the doctor blade for a paper/board machine by a pultrusion method is also disclosed.

Abstract: A heated roll and a method for heating of a roll, in particular of a press roll or calender roll in a paper or board machine. The roll has a hollow, tubular roll mantle. The roll is heated with electric current by means of electrical resistors fitted inside the body material of roll mantle. The heating is preferably applied to the roll substantially at the proximity of the face of the roll mantle, and the electric current may be supplied to the electrical resistors from the ends of the roll through glide rings.

Abstract: A roll for use in the manufacture of paper and board, a press roll, in particular a center roll in a press, a backup roll for an extended-nip press roll, a hot press roll, or equivalent, which is in direct contact with a wet paper web, or a calender roll, a method for manufacturing the same and a coating composition therefor including an adhesion layer arranged on the frame part of the roll and a ceramic layer arranged on the adhesion layer. The ceramic layer has a thickness of from about 100 &mgr;m to about 2000 &mgr;m and includes from about 50% to about 95% by weight of Cr2O3 and from about 3% to about 50% by weight of TiO2, or from about 50% to about 80% by weight of Al2O3 and from about 20% to about 50% by weight of ZrO2, or exclusively Al2TiO5. The outer face of the ceramic layer is finished until the roughness Ra is from about 0.2 &mgr;m to about 2.0 &mgr;m and/or the porosity of the outer face of the roll is from about 1% to about 20%.

Abstract: The invention concerns a caring doctor blade for a paper/board machine, which blade comprises layers of fiberglass and carbon fiber and a caring layer as a rigid laminated structure, which caring layer comprises carbon fiber and grinding particles in direct vicinity of the carbon fibers. The orientation of the fiberglass layers is parallel to the longitudinal axis of the blade, and at least in some of the layers that contain carbon fiber the orientation of the carbon fibers is substantially diverging from the direction of the longitudinal axis of the blade. The invention also concerns a method for manufacture of a doctor blade for a paper/board machine by means of a pultrusion method.

Abstract: An arrangement for improving the beginning of the drying section joined to a closed web transfer between the press section and the drying section in a paper machine. In order to achieve less fouling of the drying cylinder, that is, less formation of fluff, to achieve easier doctorability and better doctoring tolerance of the drying cylinder surface in the drying section, the surface of at least the first drying cylinder in the drying section has a coating which includes a thin preferably hard layer of ceramic material and/or metal ceramic and/or metal, to which the web will adhere weakly, and/or another softer material, to which the web will adhere weakly, is absorbed into the drying cylinder surface, whereby separation of the web from the surface of the drying cylinder is improved.

Abstract: A roll for use in the manufacture of paper and board, a press roll, in particular a center roll in a press, a backup roll for an extended-nip press roll, a hot press roll, or equivalent, which is in direct contact with a wet paper web, or a calender roll, a method for manufacturing the same and a coating composition therefor including an adhesion layer arranged on the frame part of the roll and a ceramic layer arranged on the adhesion layer. The ceramic layer has a thickness of from about 100 &mgr;m to about 2000 &mgr;m and includes from about 50% to about 95% by weight of Cr2O3 and from about 3% to about 50% by weight of TiO2, or from about 50% to about 80% by weight of Al2O3 and from about 20% to about 50% by weight of ZrO2, or exclusively Al2TiO5. The outer face of the ceramic layer is finished until the roughness Ra is from about 0.2 &mgr;m to about 2.0 &mgr;m and/or the porosity of the outer face of the roll is from about 1% to about 20%.