Abstract: An apparatus for supporting a roll mantle of a roll for a paper machine or equivalent in a lateral direction, in particular in the direction transverse to a principal loading direction, such as the nip plane. The roll mantle is rotatingly supported on a stationary roll axle, e.g., by support and loading members, and is displaceable in relation to the axle substantially in the principal loading direction. The roll mantle is also supported on the roll axle radially by glide bearing elements acting in opposite radial directions so that, when the roll mantle is displaced in the principal loading direction, the movement of the roll mantle is guided to take place along a predetermined path.

Abstract: Method and device in the press section of a paper machine for detaching a web from a smooth mantle face of a press roll. In the method and device, a transfer zone is employed, over which a press fabric or a particular transfer fabric is passed so as to accomplish a closed draw of the web. The transfer zone as well as the fabric form a transfer nip or a transfer zone with the roll face. At the transfer point, the temperature level of the roll face and/or of the web is set or regulated so high that the pressure of saturated vapor of the water present in connection with the web and with the roll face which corresponds to the temperature level is substantially equally high as, or just little higher than, the pressure that has been set to prevail in the transfer zone, the pressure being preferably lower than the atmospheric pressure.

Abstract: A method for providing a tubular roll mantle of a roll for a paper machine or equivalent with glide bearings and a roll including glide-bearings. The roll mantle is supported on a stationary roll axle by hydraulic glide-bearing members acting upon the roll mantle or upon the roll ends. The bearing members are loaded hydraulically by a pressure medium. The roll mantle is supported on the roll axle by at least one pair of glide-bearing members which acting radially and/or axially in opposite directions. When an outside force that shifts or attempts to shift the roll mantle in the direction transverse to the main loading direction and/or in the axial direction is applied to the roll mantle, the pressure in the glide-bearing member placed at the side of the higher loading is adjusted to a level higher than the pressure in the glide-bearing member acting in the opposite direction so that the outside forces are neutralized.

Abstract: The invention relates to a method for heating a roll and a heatable roll for use in a paper machine, paper finishing machine, or equivalent. The roll is heated by a heating medium which is introduced into the roll interior through at least one of the ends of the roll. The heating medium acts upon the material of the roll mantle or the roll and is arranged to flow across the axial length of the roll. The heating medium is arranged to flow out of the roll through either one of the ends of the roll. The roll is provided with means by which the coefficient of heat transfer from the flowing heating medium to the material of the roll is increased in the flow direction of the heating medium.

Abstract: A method for providing a tubular roll mantle of a roll for a paper machine or equivalent with glide bearings and a roll including glide-bearings. The roll mantle is supported on a stationary roll axle by hydraulic glide-bearing members acting upon the roll mantle or upon the roll ends. The bearing members are loaded hydraulically by a pressure medium. The roll mantle is supported on the roll axle by at least one pair of glide-bearing members which acting radially and/or axially in opposite directions. When an outside force that shifts or attempts to shift the roll mantle in the direction transverse to the main loading direction and/or in the axial direction is applied to the roll mantle, the pressure in the glide-bearing member placed at the side of the higher loading is adjusted to a level higher than the pressure in the glide-bearing member acting in the opposite direction so that the outside forces are neutralized.

Abstract: The invention concerns an adjustable-crown roll having a stationary roll axle which is supported on the machine frame by means of articulated bearings, and a roll mantle which is arranged to revolve on the axle. Hydrostatic loading members or an equivalent pressure fluid chamber or series of chambers are arranged in the space between the axle and the roll mantle. By means of the loading members or equivalent, the profile of a nip formed with a counter-roll of the roll is regulated. A support bushing arranged concentrically with the roll mantle is attached to one end of the roll mantle and revolves along with the roll mantle. A bearing is installed on the support bushing. The bearing receives axial forces from the roll mantle and transfers the same to the machine frame through the non-revolving bearing block or housing of the bearing. The bearing is arranged, in the axial direction, outside the roll, whereby the roll is suitable for use as a hot roll.

Abstract: Method and device for controlling a wire in the forming gap of a twin-wire web former of a paper machine, which gap is defined between two opposite forming wires. A pulp suspension jet is fed out of the discharge opening of the headbox of the paper machine into the forming gap. The jet has a free flight distance before it meets the forming wires. In the area of the forming gap, a variable-crown or adjustable-crown breast roll is employed as the breast roll of at least one of the wires. The deflection of the mantle of this breast roll is regulated actively from inside the mantle of the breast roll. In this manner, the transverse tightness profile of the wire guided by the breast roll and/or possible instabilities of the wire is/are controlled in particular in the area of the forming gap.

Abstract: The invention relates to a method for heating a roll and a heatable roll for use in a paper machine, paper finishing machine, or equivalent. The roll is heated by a heating medium which is introduced into the roll interior through at least one of the ends of the roll. The heating medium acts upon the material of the roll mantle or the roll and is arranged to flow across the axial length of the roll. The heating medium is arranged to flow out of the roll through either one of the ends of the roll. The roll is provided with means by which the coefficient of heat transfer from the flowing heating medium to the material of the roll is increased in the flow direction of the heating medium.

Abstract: A calender in a paper or board machine comprises a calender frame, at least two soft-faced rolls mounted on the calender frame and at least one hard roll mounted on the calender frame in a manner that allows the hard roll to be displaced between a first position in which it forms calendering nips with the two soft-faced rolls and a second position in which it is spaced from the soft-faced rolls. During threading of the web; while the calender is in operation, the hard roll is shifted to its second position, the web is passed over the soft-faced rolls, and the hard roll is shifted back to its first position and brings the web into the nips between the hard roll and the soft-faced rolls.

Abstract: The invention concerns an adjustable-crown roll having a stationary roll axle which is supported on the machine frame by means of articulated bearings, and a roll mantle which is arranged to revolve on the axle. Hydrostatic loading members or an equivalent pressure fluid chamber or series of chambers are arranged in the space between the axle and the roll mantle. By means of the loading members or equivalent, the profile of a nip formed with a counter-roll of the roll is regulated. A support bushing arranged concentrically with the roll mantle is attached to one end of the roll mantle and revolves along with the roll mantle. A bearing is installed on the support bushing. The bearing receives axial forces from the roll mantle and transfers the same to the machine frame through the non-revolving bearing bock or housing of the bearing. The bearing is arranged, in the axial direction, outside the roll, whereby the roll is suitable for use as a hot roll.

Abstract: The invention concerns a method and apparatus for regulating the temperature of an adjustable-crown roll. The roll mantle (12) arranged to revolve on the stationary axle (11) of the roll (10) is loaded by passing a pressure medium into a pressure chamber (15) or series of chambers formed between the axle (11) and the mantle (12) so as to correct the deflection of the roll mantle (12). The roll (10) is additionally heated/cooled by passing heating/cooling fluid into the roll (10). The heating/cooling fluid used for the regulation of the temperature of the roll (10) is introduced into the roll (10) so as to be substantially uniformly distributed over the surface area of the roll (10) such that heat is removed or produced in the radial direction of the roll.

Abstract: The invention concerns a fluid distribution system for a variable-crown roll adjustable in zones, this roll having a stationary central axle and a revolving roll mantle arranged on the axle. Hydraulic loading elements acting upon an inner face of the roll mantle or a corresponding pressure-fluid chamber, or a series of chambers, may be provided in a space between the central axle and the mantle, so that the axial profile of the variable-crown roll can be adjusted. The fluid distribution system of the roll has a system of fluid distribution ducts provided in connection with the central axle, with pressure fluid passing to zones of the roll being arranged to be supplied through this system. The system of fluid distribution ducts has an oblong, continuous profile of substantially circular section, which is provided with several axial ducts and with transverse bores for passing the fluid at least to the hydraulic loading elements.

Abstract: A support arrangement is provided for a variable-crown having a non-revolving roll axle (11) on which the roll mantle (12) revolves. The roll mantle (12) is supported on the roll axle (11) by means of hydraulic loading members (20) which comprise pistons (21) fitted into cylinder bores (15) formed in the roll axle (11), as well as glide shoes (22) supported on the inner face (14) of the roll mantle. The pistons (21) are composed of bushings provided with inside cavity spaces (23). The glide shoes (22), which are attached to the outer ends of the pistons through the cavity spaces (23) from outside the bushings, are hydraulically sealed (30), and are pivotal and displaceable in the radial direction of the roll (10). A hydraulic pressure medium is passed into the cavity spaces (23) in the pistons (21) so as to act upon the interior of the glide shoes (22).

Abstract: A supercalender comprises a stationary variable-crown upper roll (1), a floating variable-crown lower roll (2), several intermediate rolls (3,4) between the upper roll (1) and the lower roll (2), and a hydraulic control system. The upper roll (1) has a roll mantle (12) that is supported on the roll shaft (11) by hydrostatic loading elements (13) acting in the direction of compression and by end bearings at the ends of the roll mantle, which bearings prevent displacement of the mantle (12) ends in the radial direction relative to the shaft (11) of the upper roll. The lower roll (2) has a roll mantle (22) that is supported on the roll shaft (21) adjustably in the direction of compression by means of hydrostatic loading elements (23). Position detectors (23,31) are provided at the ends of the shaft of at least one roll.

Abstract: Method and device in a press section of a paper machine for detaching a web from a smooth face of a press roll. Momentary and local heating effect is directed at the web from outside the roll within the area or vicinity of a detaching point thereof. Material is used as the mantle or outer coating of the smooth-face roll which is at least somewhat magnetically conductive. An inductive heating effect is applied to the roll mantle free of contact therewith, and of such a high frequency, that depth of penetration of the heating effect remains sufficiently low in view of the local and momentary nature. Due to this heating effect, water present between the web and roll face is heated, even vaporized locally within the area of the detaching point, thereby detaching the web from the roll face. The electrical frequency of the induction heating is generally within the range of about 0.5 to 2 mHz, preferably within the range of about 0.8 to 1.5 mHz.

Abstract: Method in an adjustable-crown roll, in which a series of hydraulic loading elements is used. A central axle of the roll is supported by axle journals, by means of deflection bearings. A cross-section of the central axle is shaped such that the axle has sufficiently high rigidity in a nip plane. In the method, the central axle is rotated about its deflection bearings over an angle, which may be within the range of about 30.degree. to 180.degree.. A free space that is created or enlarged between the central axle and a roll mantle thereby, and provided between the central axle and an inner surface of the roll mantle, is utilized as an opening gap for the nip formed by the variable-crown roll, by allowing the roll mantle to be shifted, e.g. by the effect of gravity, or by affirmatively shifting the mantle relative to the rotated central axle.

Abstract: A method and apparatus for obtaining substantially uniform profiles of the roll mantles of an adjustable-crown roll and a counter-roll at a nip formed therebetween wherein the bearing distance of the counter-roll is substantially larger than the bearing distance of the adjustable-crown roll and wherein the nip is loaded by load forces applied to one or both rolls, preferably at regions of the bearings. A compensation moment is produced by devices situated within the mantle of the adjustable-crown roll between the bearings thereof loading both end regions of the roll mantle, the magnitude of the moment adjustable by adjusting the moment-producing compensation force such that the profiles of the deflected roll mantles of the adjustable-crown roll and the counter-roll at the nip are substantially uniform.

Abstract: A glide shoe arrangement for a variable crown roll is disclosed. The roll comprises a fixed central axle on which a hollow cylindrical roll mantle is rotatably journalled. A series of piston-glide shoe arrangements are fitted along the length of the roll between the axle and the inner surface of the roll mantle and are adapted to be loaded by hydraulic pressure fluid so that each piston loads a corresponding glide shoe against the inner surface of the roll mantle to control the distribution of nip pressure in a nip formed by the variable crown roll and a counter roll. The piston-glide shoe arrangements are fitted in cylinder bores formed in the axle. Spherical surface bearings are fitted between the loading pistons and the glide shoes, the center of curvature or rotation of the bearing surfaces being located on the side of the glide shoe. A pin-shaped projection is fitted in the loading piston and extends through the spherical bearing.

Abstract: A variable-crown roll for forming a nip with a counter-roll includes a rotatably mounted roll mantle and a fixed central axle situated within the roll mantle defining a space therebetween in which nip profile adjustment devices, such as hydrodynamic glide-shoes mounted on pistons, are provided. The roll mantle is journaled on the central axle which in turn is supported at its ends at points axially outside of the journaling points of the roll mantle. An annular member is provided between each of the end portions of the central axle within the mantle or an extension thereof. A bearing or bearings for journaling the roll mantle on the fixed central shaft is mounted at each end of the roll between a respective annular part and an end region of the mantle or an extension thereof. Hydraulic power devices are provided at each end of the roll between the annular part and the end portion of the central axle which act in the plane of the nip.